[RFC PATCH v5 0/4] RISC-V Smstateen support

[RFC PATCH v5 0/4] RISC-V Smstateen support

[Mayuresh Chitale]

This series adds support for the Smstateen specification which provides
a mechanism plug potential covert channels which are opened by extensions
that add to processor state that may not get context-switched. Currently
access to AIA registers, *envcfg registers and floating point(fcsr) is
controlled via smstateen.

These patches can also be found on riscv_smstateen_v5 branch at:
https://github.com/mdchitale/qemu.git

This series depends on the following series from Anup:
https://lists.nongnu.org/archive/html/qemu-devel/2022-05/msg05231.html

Changes in v5:
- Fix the order in which smstateen extension is added to the isa_edata_arr as
described in rule #3 the comment.

Changes in v4:
- Fix build issue with riscv32/riscv64-linux-user targets

Changes in v3:
- Fix coding style issues
- Fix *stateen0h index calculation

Changes in v2:
- Make h/s/envcfg bits in m/h/stateen registers as writeable by default.

Anup Patel (1):
  target/riscv: Force disable extensions if priv spec version does not
    match

Mayuresh Chitale (4):
  target/riscv: Add smstateen support
  target/riscv: smstateen check for h/senvcfg
  target/riscv: smstateen check for fcsr
  target/riscv: smstateen check for AIA/IMSIC

 target/riscv/cpu.c      |   2 +
 target/riscv/cpu.h      |   4 +
 target/riscv/cpu_bits.h |  36 +++
 target/riscv/csr.c      | 555 +++++++++++++++++++++++++++++++++++++++-
 target/riscv/machine.c  |  21 ++
 5 files changed, 615 insertions(+), 3 deletions(-)

-- 
2.25.1

[RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Mayuresh Chitale]

Smstateen extension specifies a mechanism to close
the potential covert channels that could cause security issues.

This patch adds the CSRs defined in the specification and
the corresponding predicates and read/write functions.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
---
 target/riscv/cpu.c      |   2 +
 target/riscv/cpu.h      |   4 +
 target/riscv/cpu_bits.h |  36 +++++++
 target/riscv/csr.c      | 210 ++++++++++++++++++++++++++++++++++++++++
 target/riscv/machine.c  |  21 ++++
 5 files changed, 273 insertions(+)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index e6e878ceb3..2d65ccd90f 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
     DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
     DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
+    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen, false),
 
     DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
     DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
@@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, int max_str_len)
         ISA_EDATA_ENTRY(zve64f, ext_zve64f),
         ISA_EDATA_ENTRY(zhinx, ext_zhinx),
         ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
+        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
         ISA_EDATA_ENTRY(svinval, ext_svinval),
         ISA_EDATA_ENTRY(svnapot, ext_svnapot),
         ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index f08c3e8813..1c269b77bd 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -327,6 +327,9 @@ struct CPUArchState {
 
     /* CSRs for execution enviornment configuration */
     uint64_t menvcfg;
+    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
+    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
+    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
     target_ulong senvcfg;
     uint64_t henvcfg;
 #endif
@@ -411,6 +414,7 @@ struct RISCVCPUConfig {
     bool ext_zhinxmin;
     bool ext_zve32f;
     bool ext_zve64f;
+    bool ext_smstateen;
 
     uint32_t mvendorid;
     uint64_t marchid;
diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
index 4a55c6a709..2a3ef26d21 100644
--- a/target/riscv/cpu_bits.h
+++ b/target/riscv/cpu_bits.h
@@ -208,6 +208,12 @@
 /* Supervisor Configuration CSRs */
 #define CSR_SENVCFG         0x10A
 
+/* Supervisor state CSRs */
+#define CSR_SSTATEEN0       0x10C
+#define CSR_SSTATEEN1       0x10D
+#define CSR_SSTATEEN2       0x10E
+#define CSR_SSTATEEN3       0x10F
+
 /* Supervisor Trap Handling */
 #define CSR_SSCRATCH        0x140
 #define CSR_SEPC            0x141
@@ -257,6 +263,16 @@
 #define CSR_HENVCFG         0x60A
 #define CSR_HENVCFGH        0x61A
 
+/* Hypervisor state CSRs */
+#define CSR_HSTATEEN0       0x60C
+#define CSR_HSTATEEN0H      0x61C
+#define CSR_HSTATEEN1       0x60D
+#define CSR_HSTATEEN1H      0x61D
+#define CSR_HSTATEEN2       0x60E
+#define CSR_HSTATEEN2H      0x61E
+#define CSR_HSTATEEN3       0x60F
+#define CSR_HSTATEEN3H      0x61F
+
 /* Virtual CSRs */
 #define CSR_VSSTATUS        0x200
 #define CSR_VSIE            0x204
@@ -304,6 +320,26 @@
 #define CSR_MENVCFG         0x30A
 #define CSR_MENVCFGH        0x31A
 
+/* Machine state CSRs */
+#define CSR_MSTATEEN0       0x30C
+#define CSR_MSTATEEN0H      0x31C
+#define CSR_MSTATEEN1       0x30D
+#define CSR_MSTATEEN1H      0x31D
+#define CSR_MSTATEEN2       0x30E
+#define CSR_MSTATEEN2H      0x31E
+#define CSR_MSTATEEN3       0x30F
+#define CSR_MSTATEEN3H      0x31F
+
+/* Common defines for all smstateen */
+#define SMSTATEEN_MAX_COUNT 4
+#define SMSTATEEN0_CS       0
+#define SMSTATEEN0_FCSR     0
+#define SMSTATEEN0_IMSIC    58
+#define SMSTATEEN0_AIA      59
+#define SMSTATEEN0_SVSLCT   60
+#define SMSTATEEN0_HSENVCFG 62
+#define SMSTATEEN_STATEN    63
+
 /* Enhanced Physical Memory Protection (ePMP) */
 #define CSR_MSECCFG         0x747
 #define CSR_MSECCFGH        0x757
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 409a209f14..324fefce59 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -247,6 +247,42 @@ static RISCVException hmode32(CPURISCVState *env, int csrno)
 
 }
 
+static RISCVException mstateen(CPURISCVState *env, int csrno)
+{
+    CPUState *cs = env_cpu(env);
+    RISCVCPU *cpu = RISCV_CPU(cs);
+
+    if (!cpu->cfg.ext_smstateen) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    return any(env, csrno);
+}
+
+static RISCVException hstateen(CPURISCVState *env, int csrno)
+{
+    CPUState *cs = env_cpu(env);
+    RISCVCPU *cpu = RISCV_CPU(cs);
+
+    if (!cpu->cfg.ext_smstateen) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    return hmode(env, csrno);
+}
+
+static RISCVException sstateen(CPURISCVState *env, int csrno)
+{
+    CPUState *cs = env_cpu(env);
+    RISCVCPU *cpu = RISCV_CPU(cs);
+
+    if (!cpu->cfg.ext_smstateen) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    return smode(env, csrno);
+}
+
 /* Checks if PointerMasking registers could be accessed */
 static RISCVException pointer_masking(CPURISCVState *env, int csrno)
 {
@@ -1574,6 +1610,129 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
     return RISCV_EXCP_NONE;
 }
 
+static inline void write_smstateen(CPURISCVState *env, uint64_t *reg,
+                                   uint64_t wr_mask, uint64_t new_val)
+{
+    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
+}
+
+static RISCVException read_mstateen(CPURISCVState *env, int csrno,
+                                    target_ulong *val)
+{
+    *val = env->mstateen[csrno - CSR_MSTATEEN0];
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_mstateen(CPURISCVState *env, int csrno,
+                                     target_ulong new_val)
+{
+    uint64_t *reg;
+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+
+    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
+    write_smstateen(env, reg, wr_mask, new_val);
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_mstateenh(CPURISCVState *env, int csrno,
+                                     target_ulong *val)
+{
+    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
+                                      target_ulong new_val)
+{
+    uint64_t *reg;
+    uint64_t val;
+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+
+    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
+    val = (uint64_t)new_val << 32;
+    val |= *reg & 0xFFFFFFFF;
+    write_smstateen(env, reg, wr_mask, val);
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_hstateen(CPURISCVState *env, int csrno,
+                                    target_ulong *val)
+{
+    *val = env->hstateen[csrno - CSR_HSTATEEN0];
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_hstateen(CPURISCVState *env, int csrno,
+                                     target_ulong new_val)
+{
+    uint64_t *reg;
+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+    int index = csrno - CSR_HSTATEEN0;
+
+    reg = &env->hstateen[index];
+    wr_mask &= env->mstateen[index];
+    write_smstateen(env, reg, wr_mask, new_val);
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_hstateenh(CPURISCVState *env, int csrno,
+                                     target_ulong *val)
+{
+    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
+                                      target_ulong new_val)
+{
+    uint64_t *reg;
+    uint64_t val;
+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+    int index = csrno - CSR_HSTATEEN0H;
+
+    reg = &env->hstateen[index];
+    val = (uint64_t)new_val << 32;
+    val |= *reg & 0xFFFFFFFF;
+    wr_mask &= env->mstateen[index];
+
+    write_smstateen(env, reg, wr_mask, val);
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_sstateen(CPURISCVState *env, int csrno,
+                                    target_ulong *val)
+{
+    *val = env->sstateen[csrno - CSR_SSTATEEN0];
+
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_sstateen(CPURISCVState *env, int csrno,
+                                     target_ulong new_val)
+{
+    uint64_t *reg;
+    uint64_t wr_mask = 0;
+    int index = csrno - CSR_SSTATEEN0;
+    bool virt = riscv_cpu_virt_enabled(env);
+
+    reg = &env->sstateen[index];
+    if (virt) {
+        wr_mask &= env->mstateen[index];
+    } else {
+        wr_mask &= env->hstateen[index];
+    }
+    write_smstateen(env, reg, wr_mask, new_val);
+
+    return RISCV_EXCP_NONE;
+}
+
 static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
                                 uint64_t *ret_val,
                                 uint64_t new_val, uint64_t wr_mask)
@@ -3441,6 +3600,57 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
     [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh, write_henvcfgh,
                                           .min_priv_ver = PRIV_VERSION_1_12_0 },
 
+    /* Smstateen extension CSRs */
+    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen, write_mstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen, read_mstateenh,
+                          write_mstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen, write_mstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen, read_mstateenh,
+                          write_mstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen, write_mstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen, read_mstateenh,
+                          write_mstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen, write_mstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen, read_mstateenh,
+                          write_mstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+
+    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen, write_hstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen, read_hstateenh,
+                          write_hstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen, write_hstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen, read_hstateenh,
+                          write_hstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen, write_hstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen, read_hstateenh,
+                          write_hstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen, write_hstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen, read_hstateenh,
+                          write_hstateenh,
+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
+
+    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen, write_sstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen, write_sstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen, write_sstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
+    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen, write_sstateen,
+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
     /* Supervisor Trap Setup */
     [CSR_SSTATUS]    = { "sstatus",    smode, read_sstatus,    write_sstatus, NULL,
                                               read_sstatus_i128                 },
diff --git a/target/riscv/machine.c b/target/riscv/machine.c
index 2a437b29a1..84a75dbb08 100644
--- a/target/riscv/machine.c
+++ b/target/riscv/machine.c
@@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void *opaque, int version_id)
     return 0;
 }
 
+static bool smstateen_needed(void *opaque)
+{
+    RISCVCPU *cpu = opaque;
+
+    return cpu->cfg.ext_smstateen;
+}
+
+static const VMStateDescription vmstate_smstateen = {
+    .name = "cpu/smtateen",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = smstateen_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
+        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
+        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 static bool envcfg_needed(void *opaque)
 {
     RISCVCPU *cpu = opaque;
@@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu = {
         &vmstate_kvmtimer,
         &vmstate_envcfg,
         &vmstate_debug,
+        &vmstate_smstateen,
         NULL
     }
 };
-- 
2.25.1

Re: [RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Alistair Francis]

On Sat, Jun 4, 2022 at 2:13 AM Mayuresh Chitale
<mchitale@ventanamicro.com> wrote:
>
> Smstateen extension specifies a mechanism to close
> the potential covert channels that could cause security issues.
>
> This patch adds the CSRs defined in the specification and
> the corresponding predicates and read/write functions.
>
> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> ---
>  target/riscv/cpu.c      |   2 +
>  target/riscv/cpu.h      |   4 +
>  target/riscv/cpu_bits.h |  36 +++++++
>  target/riscv/csr.c      | 210 ++++++++++++++++++++++++++++++++++++++++
>  target/riscv/machine.c  |  21 ++++
>  5 files changed, 273 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index e6e878ceb3..2d65ccd90f 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
>      DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
>      DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
>      DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
> +    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen, false),

This allows a user to enable this extension. It should be a seperate
patch at the end of the series. The idea is that we add support, then
once it's fully supported we allow a user to enable the extension.

>
>      DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
>      DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
> @@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, int max_str_len)
>          ISA_EDATA_ENTRY(zve64f, ext_zve64f),
>          ISA_EDATA_ENTRY(zhinx, ext_zhinx),
>          ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
> +        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
>          ISA_EDATA_ENTRY(svinval, ext_svinval),
>          ISA_EDATA_ENTRY(svnapot, ext_svnapot),
>          ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index f08c3e8813..1c269b77bd 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -327,6 +327,9 @@ struct CPUArchState {
>
>      /* CSRs for execution enviornment configuration */
>      uint64_t menvcfg;
> +    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
> +    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
> +    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
>      target_ulong senvcfg;
>      uint64_t henvcfg;
>  #endif
> @@ -411,6 +414,7 @@ struct RISCVCPUConfig {
>      bool ext_zhinxmin;
>      bool ext_zve32f;
>      bool ext_zve64f;
> +    bool ext_smstateen;
>
>      uint32_t mvendorid;
>      uint64_t marchid;
> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> index 4a55c6a709..2a3ef26d21 100644
> --- a/target/riscv/cpu_bits.h
> +++ b/target/riscv/cpu_bits.h
> @@ -208,6 +208,12 @@
>  /* Supervisor Configuration CSRs */
>  #define CSR_SENVCFG         0x10A
>
> +/* Supervisor state CSRs */
> +#define CSR_SSTATEEN0       0x10C
> +#define CSR_SSTATEEN1       0x10D
> +#define CSR_SSTATEEN2       0x10E
> +#define CSR_SSTATEEN3       0x10F
> +
>  /* Supervisor Trap Handling */
>  #define CSR_SSCRATCH        0x140
>  #define CSR_SEPC            0x141
> @@ -257,6 +263,16 @@
>  #define CSR_HENVCFG         0x60A
>  #define CSR_HENVCFGH        0x61A
>
> +/* Hypervisor state CSRs */
> +#define CSR_HSTATEEN0       0x60C
> +#define CSR_HSTATEEN0H      0x61C
> +#define CSR_HSTATEEN1       0x60D
> +#define CSR_HSTATEEN1H      0x61D
> +#define CSR_HSTATEEN2       0x60E
> +#define CSR_HSTATEEN2H      0x61E
> +#define CSR_HSTATEEN3       0x60F
> +#define CSR_HSTATEEN3H      0x61F
> +
>  /* Virtual CSRs */
>  #define CSR_VSSTATUS        0x200
>  #define CSR_VSIE            0x204
> @@ -304,6 +320,26 @@
>  #define CSR_MENVCFG         0x30A
>  #define CSR_MENVCFGH        0x31A
>
> +/* Machine state CSRs */
> +#define CSR_MSTATEEN0       0x30C
> +#define CSR_MSTATEEN0H      0x31C
> +#define CSR_MSTATEEN1       0x30D
> +#define CSR_MSTATEEN1H      0x31D
> +#define CSR_MSTATEEN2       0x30E
> +#define CSR_MSTATEEN2H      0x31E
> +#define CSR_MSTATEEN3       0x30F
> +#define CSR_MSTATEEN3H      0x31F
> +
> +/* Common defines for all smstateen */
> +#define SMSTATEEN_MAX_COUNT 4
> +#define SMSTATEEN0_CS       0
> +#define SMSTATEEN0_FCSR     0
> +#define SMSTATEEN0_IMSIC    58
> +#define SMSTATEEN0_AIA      59
> +#define SMSTATEEN0_SVSLCT   60
> +#define SMSTATEEN0_HSENVCFG 62
> +#define SMSTATEEN_STATEN    63
> +
>  /* Enhanced Physical Memory Protection (ePMP) */
>  #define CSR_MSECCFG         0x747
>  #define CSR_MSECCFGH        0x757
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 409a209f14..324fefce59 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -247,6 +247,42 @@ static RISCVException hmode32(CPURISCVState *env, int csrno)
>
>  }
>
> +static RISCVException mstateen(CPURISCVState *env, int csrno)
> +{
> +    CPUState *cs = env_cpu(env);
> +    RISCVCPU *cpu = RISCV_CPU(cs);
> +
> +    if (!cpu->cfg.ext_smstateen) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +
> +    return any(env, csrno);
> +}
> +
> +static RISCVException hstateen(CPURISCVState *env, int csrno)
> +{
> +    CPUState *cs = env_cpu(env);
> +    RISCVCPU *cpu = RISCV_CPU(cs);
> +
> +    if (!cpu->cfg.ext_smstateen) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +
> +    return hmode(env, csrno);
> +}
> +
> +static RISCVException sstateen(CPURISCVState *env, int csrno)
> +{
> +    CPUState *cs = env_cpu(env);
> +    RISCVCPU *cpu = RISCV_CPU(cs);
> +
> +    if (!cpu->cfg.ext_smstateen) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +
> +    return smode(env, csrno);
> +}
> +
>  /* Checks if PointerMasking registers could be accessed */
>  static RISCVException pointer_masking(CPURISCVState *env, int csrno)
>  {
> @@ -1574,6 +1610,129 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
>      return RISCV_EXCP_NONE;
>  }
>
> +static inline void write_smstateen(CPURISCVState *env, uint64_t *reg,
> +                                   uint64_t wr_mask, uint64_t new_val)
> +{
> +    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
> +}
> +
> +static RISCVException read_mstateen(CPURISCVState *env, int csrno,
> +                                    target_ulong *val)
> +{
> +    *val = env->mstateen[csrno - CSR_MSTATEEN0];
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException write_mstateen(CPURISCVState *env, int csrno,
> +                                     target_ulong new_val)
> +{
> +    uint64_t *reg;
> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;

I'm not sure I understand, why is only bit 63 writable?

I guess you plan on expanding this, maybe make this a single const (or
macro) that can be shared between them all?

> +
> +    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> +    write_smstateen(env, reg, wr_mask, new_val);
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException read_mstateenh(CPURISCVState *env, int csrno,
> +                                     target_ulong *val)
> +{
> +    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
> +                                      target_ulong new_val)
> +{
> +    uint64_t *reg;
> +    uint64_t val;
> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +
> +    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> +    val = (uint64_t)new_val << 32;
> +    val |= *reg & 0xFFFFFFFF;
> +    write_smstateen(env, reg, wr_mask, val);
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException read_hstateen(CPURISCVState *env, int csrno,
> +                                    target_ulong *val)
> +{
> +    *val = env->hstateen[csrno - CSR_HSTATEEN0];
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException write_hstateen(CPURISCVState *env, int csrno,
> +                                     target_ulong new_val)
> +{
> +    uint64_t *reg;
> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    int index = csrno - CSR_HSTATEEN0;
> +
> +    reg = &env->hstateen[index];
> +    wr_mask &= env->mstateen[index];
> +    write_smstateen(env, reg, wr_mask, new_val);
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException read_hstateenh(CPURISCVState *env, int csrno,
> +                                     target_ulong *val)
> +{
> +    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
> +                                      target_ulong new_val)
> +{
> +    uint64_t *reg;
> +    uint64_t val;
> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    int index = csrno - CSR_HSTATEEN0H;
> +
> +    reg = &env->hstateen[index];
> +    val = (uint64_t)new_val << 32;
> +    val |= *reg & 0xFFFFFFFF;
> +    wr_mask &= env->mstateen[index];
> +
> +    write_smstateen(env, reg, wr_mask, val);
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException read_sstateen(CPURISCVState *env, int csrno,
> +                                    target_ulong *val)
> +{
> +    *val = env->sstateen[csrno - CSR_SSTATEEN0];
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException write_sstateen(CPURISCVState *env, int csrno,
> +                                     target_ulong new_val)
> +{
> +    uint64_t *reg;
> +    uint64_t wr_mask = 0;
> +    int index = csrno - CSR_SSTATEEN0;
> +    bool virt = riscv_cpu_virt_enabled(env);
> +
> +    reg = &env->sstateen[index];
> +    if (virt) {
> +        wr_mask &= env->mstateen[index];
> +    } else {
> +        wr_mask &= env->hstateen[index];
> +    }
> +    write_smstateen(env, reg, wr_mask, new_val);
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
>  static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
>                                  uint64_t *ret_val,
>                                  uint64_t new_val, uint64_t wr_mask)
> @@ -3441,6 +3600,57 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
>      [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh, write_henvcfgh,
>                                            .min_priv_ver = PRIV_VERSION_1_12_0 },
>
> +    /* Smstateen extension CSRs */
> +    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen, write_mstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen, read_mstateenh,
> +                          write_mstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen, write_mstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen, read_mstateenh,
> +                          write_mstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen, write_mstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen, read_mstateenh,
> +                          write_mstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen, write_mstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen, read_mstateenh,
> +                          write_mstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +
> +    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen, write_hstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen, read_hstateenh,
> +                          write_hstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen, write_hstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen, read_hstateenh,
> +                          write_hstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen, write_hstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen, read_hstateenh,
> +                          write_hstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen, write_hstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen, read_hstateenh,
> +                          write_hstateenh,
> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> +
> +    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen, write_sstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen, write_sstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen, write_sstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> +    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen, write_sstateen,
> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>      /* Supervisor Trap Setup */
>      [CSR_SSTATUS]    = { "sstatus",    smode, read_sstatus,    write_sstatus, NULL,
>                                                read_sstatus_i128                 },
> diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> index 2a437b29a1..84a75dbb08 100644
> --- a/target/riscv/machine.c
> +++ b/target/riscv/machine.c
> @@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void *opaque, int version_id)
>      return 0;
>  }
>
> +static bool smstateen_needed(void *opaque)
> +{
> +    RISCVCPU *cpu = opaque;
> +
> +    return cpu->cfg.ext_smstateen;
> +}
> +
> +static const VMStateDescription vmstate_smstateen = {
> +    .name = "cpu/smtateen",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .needed = smstateen_needed,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
> +        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
> +        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
>  static bool envcfg_needed(void *opaque)
>  {
>      RISCVCPU *cpu = opaque;
> @@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu = {
>          &vmstate_kvmtimer,
>          &vmstate_envcfg,
>          &vmstate_debug,
> +        &vmstate_smstateen,
>          NULL
>      }
>  };
> --
> 2.25.1
>
>

Re: [RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Mayuresh Chitale]

On Thu, 2022-06-16 at 15:48 +1000, Alistair Francis wrote:
> On Sat, Jun 4, 2022 at 2:13 AM Mayuresh Chitale
> <mchitale@ventanamicro.com> wrote:
> > Smstateen extension specifies a mechanism to close
> > the potential covert channels that could cause security issues.
> > 
> > This patch adds the CSRs defined in the specification and
> > the corresponding predicates and read/write functions.
> > 
> > Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> > ---
> >  target/riscv/cpu.c      |   2 +
> >  target/riscv/cpu.h      |   4 +
> >  target/riscv/cpu_bits.h |  36 +++++++
> >  target/riscv/csr.c      | 210
> > ++++++++++++++++++++++++++++++++++++++++
> >  target/riscv/machine.c  |  21 ++++
> >  5 files changed, 273 insertions(+)
> > 
> > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> > index e6e878ceb3..2d65ccd90f 100644
> > --- a/target/riscv/cpu.c
> > +++ b/target/riscv/cpu.c
> > @@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
> >      DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
> >      DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
> >      DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
> > +    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen,
> > false),
> 
> This allows a user to enable this extension. It should be a seperate
> patch at the end of the series. The idea is that we add support, then
> once it's fully supported we allow a user to enable the extension.
> 
> >      DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
> >      DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
> > @@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU
> > *cpu, char **isa_str, int max_str_len)
> >          ISA_EDATA_ENTRY(zve64f, ext_zve64f),
> >          ISA_EDATA_ENTRY(zhinx, ext_zhinx),
> >          ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
> > +        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
> >          ISA_EDATA_ENTRY(svinval, ext_svinval),
> >          ISA_EDATA_ENTRY(svnapot, ext_svnapot),
> >          ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
> > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> > index f08c3e8813..1c269b77bd 100644
> > --- a/target/riscv/cpu.h
> > +++ b/target/riscv/cpu.h
> > @@ -327,6 +327,9 @@ struct CPUArchState {
> > 
> >      /* CSRs for execution enviornment configuration */
> >      uint64_t menvcfg;
> > +    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
> > +    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
> > +    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
> >      target_ulong senvcfg;
> >      uint64_t henvcfg;
> >  #endif
> > @@ -411,6 +414,7 @@ struct RISCVCPUConfig {
> >      bool ext_zhinxmin;
> >      bool ext_zve32f;
> >      bool ext_zve64f;
> > +    bool ext_smstateen;
> > 
> >      uint32_t mvendorid;
> >      uint64_t marchid;
> > diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> > index 4a55c6a709..2a3ef26d21 100644
> > --- a/target/riscv/cpu_bits.h
> > +++ b/target/riscv/cpu_bits.h
> > @@ -208,6 +208,12 @@
> >  /* Supervisor Configuration CSRs */
> >  #define CSR_SENVCFG         0x10A
> > 
> > +/* Supervisor state CSRs */
> > +#define CSR_SSTATEEN0       0x10C
> > +#define CSR_SSTATEEN1       0x10D
> > +#define CSR_SSTATEEN2       0x10E
> > +#define CSR_SSTATEEN3       0x10F
> > +
> >  /* Supervisor Trap Handling */
> >  #define CSR_SSCRATCH        0x140
> >  #define CSR_SEPC            0x141
> > @@ -257,6 +263,16 @@
> >  #define CSR_HENVCFG         0x60A
> >  #define CSR_HENVCFGH        0x61A
> > 
> > +/* Hypervisor state CSRs */
> > +#define CSR_HSTATEEN0       0x60C
> > +#define CSR_HSTATEEN0H      0x61C
> > +#define CSR_HSTATEEN1       0x60D
> > +#define CSR_HSTATEEN1H      0x61D
> > +#define CSR_HSTATEEN2       0x60E
> > +#define CSR_HSTATEEN2H      0x61E
> > +#define CSR_HSTATEEN3       0x60F
> > +#define CSR_HSTATEEN3H      0x61F
> > +
> >  /* Virtual CSRs */
> >  #define CSR_VSSTATUS        0x200
> >  #define CSR_VSIE            0x204
> > @@ -304,6 +320,26 @@
> >  #define CSR_MENVCFG         0x30A
> >  #define CSR_MENVCFGH        0x31A
> > 
> > +/* Machine state CSRs */
> > +#define CSR_MSTATEEN0       0x30C
> > +#define CSR_MSTATEEN0H      0x31C
> > +#define CSR_MSTATEEN1       0x30D
> > +#define CSR_MSTATEEN1H      0x31D
> > +#define CSR_MSTATEEN2       0x30E
> > +#define CSR_MSTATEEN2H      0x31E
> > +#define CSR_MSTATEEN3       0x30F
> > +#define CSR_MSTATEEN3H      0x31F
> > +
> > +/* Common defines for all smstateen */
> > +#define SMSTATEEN_MAX_COUNT 4
> > +#define SMSTATEEN0_CS       0
> > +#define SMSTATEEN0_FCSR     0
> > +#define SMSTATEEN0_IMSIC    58
> > +#define SMSTATEEN0_AIA      59
> > +#define SMSTATEEN0_SVSLCT   60
> > +#define SMSTATEEN0_HSENVCFG 62
> > +#define SMSTATEEN_STATEN    63
> > +
> >  /* Enhanced Physical Memory Protection (ePMP) */
> >  #define CSR_MSECCFG         0x747
> >  #define CSR_MSECCFGH        0x757
> > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > index 409a209f14..324fefce59 100644
> > --- a/target/riscv/csr.c
> > +++ b/target/riscv/csr.c
> > @@ -247,6 +247,42 @@ static RISCVException hmode32(CPURISCVState
> > *env, int csrno)
> > 
> >  }
> > 
> > +static RISCVException mstateen(CPURISCVState *env, int csrno)
> > +{
> > +    CPUState *cs = env_cpu(env);
> > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > +
> > +    if (!cpu->cfg.ext_smstateen) {
> > +        return RISCV_EXCP_ILLEGAL_INST;
> > +    }
> > +
> > +    return any(env, csrno);
> > +}
> > +
> > +static RISCVException hstateen(CPURISCVState *env, int csrno)
> > +{
> > +    CPUState *cs = env_cpu(env);
> > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > +
> > +    if (!cpu->cfg.ext_smstateen) {
> > +        return RISCV_EXCP_ILLEGAL_INST;
> > +    }
> > +
> > +    return hmode(env, csrno);
> > +}
> > +
> > +static RISCVException sstateen(CPURISCVState *env, int csrno)
> > +{
> > +    CPUState *cs = env_cpu(env);
> > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > +
> > +    if (!cpu->cfg.ext_smstateen) {
> > +        return RISCV_EXCP_ILLEGAL_INST;
> > +    }
> > +
> > +    return smode(env, csrno);
> > +}
> > +
> >  /* Checks if PointerMasking registers could be accessed */
> >  static RISCVException pointer_masking(CPURISCVState *env, int
> > csrno)
> >  {
> > @@ -1574,6 +1610,129 @@ static RISCVException
> > write_henvcfgh(CPURISCVState *env, int csrno,
> >      return RISCV_EXCP_NONE;
> >  }
> > 
> > +static inline void write_smstateen(CPURISCVState *env, uint64_t
> > *reg,
> > +                                   uint64_t wr_mask, uint64_t
> > new_val)
> > +{
> > +    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
> > +}
> > +
> > +static RISCVException read_mstateen(CPURISCVState *env, int csrno,
> > +                                    target_ulong *val)
> > +{
> > +    *val = env->mstateen[csrno - CSR_MSTATEEN0];
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException write_mstateen(CPURISCVState *env, int
> > csrno,
> > +                                     target_ulong new_val)
> > +{
> > +    uint64_t *reg;
> > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> 
> I'm not sure I understand, why is only bit 63 writable?
> 
> I guess you plan on expanding this, maybe make this a single const
> (or
> macro) that can be shared between them all?
Yes, it is expanded in the later patches depending on availability of
other features.
> 
> > +
> > +    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> > +    write_smstateen(env, reg, wr_mask, new_val);
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException read_mstateenh(CPURISCVState *env, int
> > csrno,
> > +                                     target_ulong *val)
> > +{
> > +    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException write_mstateenh(CPURISCVState *env, int
> > csrno,
> > +                                      target_ulong new_val)
> > +{
> > +    uint64_t *reg;
> > +    uint64_t val;
> > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > +
> > +    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> > +    val = (uint64_t)new_val << 32;
> > +    val |= *reg & 0xFFFFFFFF;
> > +    write_smstateen(env, reg, wr_mask, val);
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException read_hstateen(CPURISCVState *env, int csrno,
> > +                                    target_ulong *val)
> > +{
> > +    *val = env->hstateen[csrno - CSR_HSTATEEN0];
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException write_hstateen(CPURISCVState *env, int
> > csrno,
> > +                                     target_ulong new_val)
> > +{
> > +    uint64_t *reg;
> > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > +    int index = csrno - CSR_HSTATEEN0;
> > +
> > +    reg = &env->hstateen[index];
> > +    wr_mask &= env->mstateen[index];
> > +    write_smstateen(env, reg, wr_mask, new_val);
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException read_hstateenh(CPURISCVState *env, int
> > csrno,
> > +                                     target_ulong *val)
> > +{
> > +    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException write_hstateenh(CPURISCVState *env, int
> > csrno,
> > +                                      target_ulong new_val)
> > +{
> > +    uint64_t *reg;
> > +    uint64_t val;
> > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > +    int index = csrno - CSR_HSTATEEN0H;
> > +
> > +    reg = &env->hstateen[index];
> > +    val = (uint64_t)new_val << 32;
> > +    val |= *reg & 0xFFFFFFFF;
> > +    wr_mask &= env->mstateen[index];
> > +
> > +    write_smstateen(env, reg, wr_mask, val);
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException read_sstateen(CPURISCVState *env, int csrno,
> > +                                    target_ulong *val)
> > +{
> > +    *val = env->sstateen[csrno - CSR_SSTATEEN0];
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException write_sstateen(CPURISCVState *env, int
> > csrno,
> > +                                     target_ulong new_val)
> > +{
> > +    uint64_t *reg;
> > +    uint64_t wr_mask = 0;
> > +    int index = csrno - CSR_SSTATEEN0;
> > +    bool virt = riscv_cpu_virt_enabled(env);
> > +
> > +    reg = &env->sstateen[index];
> > +    if (virt) {
> > +        wr_mask &= env->mstateen[index];
> > +    } else {
> > +        wr_mask &= env->hstateen[index];
> > +    }
> > +    write_smstateen(env, reg, wr_mask, new_val);
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> >  static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
> >                                  uint64_t *ret_val,
> >                                  uint64_t new_val, uint64_t
> > wr_mask)
> > @@ -3441,6 +3600,57 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE]
> > = {
> >      [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh,
> > write_henvcfgh,
> >                                            .min_priv_ver =
> > PRIV_VERSION_1_12_0 },
> > 
> > +    /* Smstateen extension CSRs */
> > +    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen,
> > write_mstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen, read_mstateenh,
> > +                          write_mstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen,
> > write_mstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen, read_mstateenh,
> > +                          write_mstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen,
> > write_mstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen, read_mstateenh,
> > +                          write_mstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen,
> > write_mstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen, read_mstateenh,
> > +                          write_mstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +
> > +    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen,
> > write_hstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen, read_hstateenh,
> > +                          write_hstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen,
> > write_hstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen, read_hstateenh,
> > +                          write_hstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen,
> > write_hstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen, read_hstateenh,
> > +                          write_hstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen,
> > write_hstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen, read_hstateenh,
> > +                          write_hstateenh,
> > +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +
> > +    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen,
> > write_sstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen,
> > write_sstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen,
> > write_sstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> > +    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen,
> > write_sstateen,
> > +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >      /* Supervisor Trap Setup */
> >      [CSR_SSTATUS]    = { "sstatus",    smode,
> > read_sstatus,    write_sstatus, NULL,
> >                                                read_sstatus_i128   
> >               },
> > diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> > index 2a437b29a1..84a75dbb08 100644
> > --- a/target/riscv/machine.c
> > +++ b/target/riscv/machine.c
> > @@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void *opaque,
> > int version_id)
> >      return 0;
> >  }
> > 
> > +static bool smstateen_needed(void *opaque)
> > +{
> > +    RISCVCPU *cpu = opaque;
> > +
> > +    return cpu->cfg.ext_smstateen;
> > +}
> > +
> > +static const VMStateDescription vmstate_smstateen = {
> > +    .name = "cpu/smtateen",
> > +    .version_id = 1,
> > +    .minimum_version_id = 1,
> > +    .needed = smstateen_needed,
> > +    .fields = (VMStateField[]) {
> > +        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
> > +        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
> > +        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
> > +        VMSTATE_END_OF_LIST()
> > +    }
> > +};
> > +
> >  static bool envcfg_needed(void *opaque)
> >  {
> >      RISCVCPU *cpu = opaque;
> > @@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu = {
> >          &vmstate_kvmtimer,
> >          &vmstate_envcfg,
> >          &vmstate_debug,
> > +        &vmstate_smstateen,
> >          NULL
> >      }
> >  };
> > --
> > 2.25.1
> > 
> > 

Re:[RFC PATCH v5 1/4] target/riscv: Add smstateen support

[angell1518]

[-- Attachment #1: Type: text/plain, Size: 15130 bytes --]

At 2022-06-04 00:04:22, "Mayuresh Chitale" <mchitale@ventanamicro.com> wrote:

>Smstateen extension specifies a mechanism to close
>the potential covert channels that could cause security issues.
>
>This patch adds the CSRs defined in the specification and
>the corresponding predicates and read/write functions.
>
>Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
>---
> target/riscv/cpu.c      |   2 +
> target/riscv/cpu.h      |   4 +
> target/riscv/cpu_bits.h |  36 +++++++
> target/riscv/csr.c      | 210 ++++++++++++++++++++++++++++++++++++++++
> target/riscv/machine.c  |  21 ++++
> 5 files changed, 273 insertions(+)
>
>diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
>index e6e878ceb3..2d65ccd90f 100644
>--- a/target/riscv/cpu.c
>+++ b/target/riscv/cpu.c
>@@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
>     DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
>     DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
>     DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
>+    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen, false),
> 
>     DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
>     DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
>@@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU *cpu, char **isa_str, int max_str_len)
>         ISA_EDATA_ENTRY(zve64f, ext_zve64f),
>         ISA_EDATA_ENTRY(zhinx, ext_zhinx),
>         ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
>+        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
>         ISA_EDATA_ENTRY(svinval, ext_svinval),
>         ISA_EDATA_ENTRY(svnapot, ext_svnapot),
>         ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
>diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
>index f08c3e8813..1c269b77bd 100644
>--- a/target/riscv/cpu.h
>+++ b/target/riscv/cpu.h
>@@ -327,6 +327,9 @@ struct CPUArchState {
> 
>     /* CSRs for execution enviornment configuration */
>     uint64_t menvcfg;
>+    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
>+    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
>+    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
>     target_ulong senvcfg;
>     uint64_t henvcfg;
> #endif
>@@ -411,6 +414,7 @@ struct RISCVCPUConfig {
>     bool ext_zhinxmin;
>     bool ext_zve32f;
>     bool ext_zve64f;
>+    bool ext_smstateen;
> 
>     uint32_t mvendorid;
>     uint64_t marchid;
>diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
>index 4a55c6a709..2a3ef26d21 100644
>--- a/target/riscv/cpu_bits.h
>+++ b/target/riscv/cpu_bits.h
>@@ -208,6 +208,12 @@
> /* Supervisor Configuration CSRs */
> #define CSR_SENVCFG         0x10A
> 
>+/* Supervisor state CSRs */
>+#define CSR_SSTATEEN0       0x10C
>+#define CSR_SSTATEEN1       0x10D
>+#define CSR_SSTATEEN2       0x10E
>+#define CSR_SSTATEEN3       0x10F
>+
> /* Supervisor Trap Handling */
> #define CSR_SSCRATCH        0x140
> #define CSR_SEPC            0x141
>@@ -257,6 +263,16 @@
> #define CSR_HENVCFG         0x60A
> #define CSR_HENVCFGH        0x61A
> 
>+/* Hypervisor state CSRs */
>+#define CSR_HSTATEEN0       0x60C
>+#define CSR_HSTATEEN0H      0x61C
>+#define CSR_HSTATEEN1       0x60D
>+#define CSR_HSTATEEN1H      0x61D
>+#define CSR_HSTATEEN2       0x60E
>+#define CSR_HSTATEEN2H      0x61E
>+#define CSR_HSTATEEN3       0x60F
>+#define CSR_HSTATEEN3H      0x61F
>+
> /* Virtual CSRs */
> #define CSR_VSSTATUS        0x200
> #define CSR_VSIE            0x204
>@@ -304,6 +320,26 @@
> #define CSR_MENVCFG         0x30A
> #define CSR_MENVCFGH        0x31A
> 
>+/* Machine state CSRs */
>+#define CSR_MSTATEEN0       0x30C
>+#define CSR_MSTATEEN0H      0x31C
>+#define CSR_MSTATEEN1       0x30D
>+#define CSR_MSTATEEN1H      0x31D
>+#define CSR_MSTATEEN2       0x30E
>+#define CSR_MSTATEEN2H      0x31E
>+#define CSR_MSTATEEN3       0x30F
>+#define CSR_MSTATEEN3H      0x31F
>+
>+/* Common defines for all smstateen */
>+#define SMSTATEEN_MAX_COUNT 4
>+#define SMSTATEEN0_CS       0
>+#define SMSTATEEN0_FCSR     0
>+#define SMSTATEEN0_IMSIC    58
>+#define SMSTATEEN0_AIA      59
>+#define SMSTATEEN0_SVSLCT   60
>+#define SMSTATEEN0_HSENVCFG 62
>+#define SMSTATEEN_STATEN    63
>+
> /* Enhanced Physical Memory Protection (ePMP) */
> #define CSR_MSECCFG         0x747
> #define CSR_MSECCFGH        0x757
>diff --git a/target/riscv/csr.c b/target/riscv/csr.c
>index 409a209f14..324fefce59 100644
>--- a/target/riscv/csr.c
>+++ b/target/riscv/csr.c
>@@ -247,6 +247,42 @@ static RISCVException hmode32(CPURISCVState *env, int csrno)
> 
> }
> 
>+static RISCVException mstateen(CPURISCVState *env, int csrno)
>+{
>+    CPUState *cs = env_cpu(env);
>+    RISCVCPU *cpu = RISCV_CPU(cs);
>+
>+    if (!cpu->cfg.ext_smstateen) {
>+        return RISCV_EXCP_ILLEGAL_INST;
>+    }
>+
>+    return any(env, csrno);
>+}
>+
>+static RISCVException hstateen(CPURISCVState *env, int csrno)
>+{
>+    CPUState *cs = env_cpu(env);
>+    RISCVCPU *cpu = RISCV_CPU(cs);
>+
>+    if (!cpu->cfg.ext_smstateen) {
>+        return RISCV_EXCP_ILLEGAL_INST;
>+    }
>+
>+    return hmode(env, csrno);
>+}
>+


I think we should take the stateen bit(bit 63) for matching mstateen into consideration here.

Similar to following sstateen function.

>+static RISCVException sstateen(CPURISCVState *env, int csrno)
>+{
>+    CPUState *cs = env_cpu(env);
>+    RISCVCPU *cpu = RISCV_CPU(cs);
>+
>+    if (!cpu->cfg.ext_smstateen) {
>+        return RISCV_EXCP_ILLEGAL_INST;
>+    }
>+
>+    return smode(env, csrno);
>+}
>+
> /* Checks if PointerMasking registers could be accessed */
> static RISCVException pointer_masking(CPURISCVState *env, int csrno)
> {
>@@ -1574,6 +1610,129 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
>     return RISCV_EXCP_NONE;
> }
> 
>+static inline void write_smstateen(CPURISCVState *env, uint64_t *reg,
>+                                   uint64_t wr_mask, uint64_t new_val)
>+{
>+    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
>+}
>+
>+static RISCVException read_mstateen(CPURISCVState *env, int csrno,
>+                                    target_ulong *val)
>+{
>+    *val = env->mstateen[csrno - CSR_MSTATEEN0];
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>+                                     target_ulong new_val)
>+{
>+    uint64_t *reg;
>+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+
>+    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>+    write_smstateen(env, reg, wr_mask, new_val);
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException read_mstateenh(CPURISCVState *env, int csrno,
>+                                     target_ulong *val)
>+{
>+    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
>+                                      target_ulong new_val)
>+{
>+    uint64_t *reg;
>+    uint64_t val;
>+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+
>+    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>+    val = (uint64_t)new_val << 32;
>+    val |= *reg & 0xFFFFFFFF;
>+    write_smstateen(env, reg, wr_mask, val);
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException read_hstateen(CPURISCVState *env, int csrno,
>+                                    target_ulong *val)
>+{
>+    *val = env->hstateen[csrno - CSR_HSTATEEN0];
>+
>+    return RISCV_EXCP_NONE;
>+}
>+


I think we should also take mstateen into consideration here just like the following write function.
As the spec said, If we set certain bit in the matching mstateen csr to zero, the same bit in hstateen should be read-only zero.
However, writes to mstateen will not affect the value in matching hstateen directly in current implementation,

so if we read hstateen just immediately after write zero to certain bit of mstateen, the same bit  read from hstateen may not be zero.


similar to read function of sstateen.


>+static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>+                                     target_ulong new_val)
>+{
>+    uint64_t *reg;
>+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+    int index = csrno - CSR_HSTATEEN0;
>+
>+    reg = &env->hstateen[index];
>+    wr_mask &= env->mstateen[index];
>+    write_smstateen(env, reg, wr_mask, new_val);
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException read_hstateenh(CPURISCVState *env, int csrno,
>+                                     target_ulong *val)
>+{
>+    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
>+                                      target_ulong new_val)
>+{
>+    uint64_t *reg;
>+    uint64_t val;
>+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+    int index = csrno - CSR_HSTATEEN0H;
>+
>+    reg = &env->hstateen[index];
>+    val = (uint64_t)new_val << 32;
>+    val |= *reg & 0xFFFFFFFF;
>+    wr_mask &= env->mstateen[index];
>+
>+    write_smstateen(env, reg, wr_mask, val);
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException read_sstateen(CPURISCVState *env, int csrno,
>+                                    target_ulong *val)
>+{
>+    *val = env->sstateen[csrno - CSR_SSTATEEN0];
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
>+static RISCVException write_sstateen(CPURISCVState *env, int csrno,
>+                                     target_ulong new_val)
>+{
>+    uint64_t *reg;
>+    uint64_t wr_mask = 0;
>+    int index = csrno - CSR_SSTATEEN0;
>+    bool virt = riscv_cpu_virt_enabled(env);
>+
>+    reg = &env->sstateen[index];
>+    if (virt) {
>+        wr_mask &= env->mstateen[index];
>+    } else {
>+        wr_mask &= env->hstateen[index];
>+    }
Why this? I think hstateen works in virt mode, so this may be:

if (virt) {

  wr_mask &= env->mstateen[index] & env->hstateen[index];;

} else {

  wr_mask &= env->mstateen[index];
}
>+    write_smstateen(env, reg, wr_mask, new_val);
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
> static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
>                                 uint64_t *ret_val,
>                                 uint64_t new_val, uint64_t wr_mask)
>@@ -3441,6 +3600,57 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
>     [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh, write_henvcfgh,
>                                           .min_priv_ver = PRIV_VERSION_1_12_0 },
> 
>+    /* Smstateen extension CSRs */
>+    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen, write_mstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen, read_mstateenh,
>+                          write_mstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen, write_mstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },


It seems unreasonable for mstateen1~3 to share the same read/write function with mstateen0 ,

since their field mask is different.
Similar to sstateen1~3 and hstateen1~3


Regards,
Weiwei Li

>+    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen, read_mstateenh,
>+                          write_mstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen, write_mstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen, read_mstateenh,
>+                          write_mstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen, write_mstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen, read_mstateenh,
>+                          write_mstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+
>+    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen, write_hstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen, read_hstateenh,
>+                          write_hstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen, write_hstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen, read_hstateenh,
>+                          write_hstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen, write_hstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen, read_hstateenh,
>+                          write_hstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen, write_hstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen, read_hstateenh,
>+                          write_hstateenh,
>+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>+
>+    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen, write_sstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen, write_sstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen, write_sstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>+    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen, write_sstateen,
>+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>     /* Supervisor Trap Setup */
>     [CSR_SSTATUS]    = { "sstatus",    smode, read_sstatus,    write_sstatus, NULL,
>                                               read_sstatus_i128                 },
>diff --git a/target/riscv/machine.c b/target/riscv/machine.c
>index 2a437b29a1..84a75dbb08 100644
>--- a/target/riscv/machine.c
>+++ b/target/riscv/machine.c
>@@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void *opaque, int version_id)
>     return 0;
> }
> 
>+static bool smstateen_needed(void *opaque)
>+{
>+    RISCVCPU *cpu = opaque;
>+
>+    return cpu->cfg.ext_smstateen;
>+}
>+
>+static const VMStateDescription vmstate_smstateen = {
>+    .name = "cpu/smtateen",
>+    .version_id = 1,
>+    .minimum_version_id = 1,
>+    .needed = smstateen_needed,
>+    .fields = (VMStateField[]) {
>+        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
>+        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
>+        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
>+        VMSTATE_END_OF_LIST()
>+    }
>+};
>+
> static bool envcfg_needed(void *opaque)
> {
>     RISCVCPU *cpu = opaque;
>@@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu = {
>         &vmstate_kvmtimer,
>         &vmstate_envcfg,
>         &vmstate_debug,
>+        &vmstate_smstateen,
>         NULL
>     }
> };
>-- 
>2.25.1
>

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Re: [RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Mayuresh Chitale]

On Sat, 2022-07-02 at 18:19 +0800, angell1518 wrote:
> At 2022-06-04 00:04:22, "Mayuresh Chitale" <mchitale@ventanamicro.com
> > wrote:
> >Smstateen extension specifies a mechanism to close
> >the potential covert channels that could cause security issues.
> >
> >This patch adds the CSRs defined in the specification and
> >the corresponding predicates and read/write functions.
> >
> >Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> >---
> > target/riscv/cpu.c      |   2 +
> > target/riscv/cpu.h      |   4 +
> > target/riscv/cpu_bits.h |  36 +++++++
> > target/riscv/csr.c      | 210
> ++++++++++++++++++++++++++++++++++++++++
> > target/riscv/machine.c  |  21 ++++
> > 5 files changed, 273 insertions(+)
> >
> >diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> >index e6e878ceb3..2d65ccd90f 100644
> >--- a/target/riscv/cpu.c
> >+++ b/target/riscv/cpu.c
> >@@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
> >     DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
> >     DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
> >     DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
> >+    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen,
> false),
> > 
> >     DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
> >     DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
> >@@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU
> *cpu, char **isa_str, int max_str_len)
> >         ISA_EDATA_ENTRY(zve64f, ext_zve64f),
> >         ISA_EDATA_ENTRY(zhinx, ext_zhinx),
> >         ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
> >+        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
> >         ISA_EDATA_ENTRY(svinval, ext_svinval),
> >         ISA_EDATA_ENTRY(svnapot, ext_svnapot),
> >         ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
> >diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> >index f08c3e8813..1c269b77bd 100644
> >--- a/target/riscv/cpu.h
> >+++ b/target/riscv/cpu.h
> >@@ -327,6 +327,9 @@ struct CPUArchState {
> > 
> >     /* CSRs for execution enviornment configuration */
> >     uint64_t menvcfg;
> >+    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
> >+    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
> >+    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
> >     target_ulong senvcfg;
> >     uint64_t henvcfg;
> > #endif
> >@@ -411,6 +414,7 @@ struct RISCVCPUConfig {
> >     bool ext_zhinxmin;
> >     bool ext_zve32f;
> >     bool ext_zve64f;
> >+    bool ext_smstateen;
> > 
> >     uint32_t mvendorid;
> >     uint64_t marchid;
> >diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> >index 4a55c6a709..2a3ef26d21 100644
> >--- a/target/riscv/cpu_bits.h
> >+++ b/target/riscv/cpu_bits.h
> >@@ -208,6 +208,12 @@
> > /* Supervisor Configuration CSRs */
> > #define CSR_SENVCFG         0x10A
> > 
> >+/* Supervisor state CSRs */
> >+#define CSR_SSTATEEN0       0x10C
> >+#define CSR_SSTATEEN1       0x10D
> >+#define CSR_SSTATEEN2       0x10E
> >+#define CSR_SSTATEEN3       0x10F
> >+
> > /* Supervisor Trap Handling */
> > #define CSR_SSCRATCH        0x140
> > #define CSR_SEPC            0x141
> >@@ -257,6 +263,16 @@
> > #define CSR_HENVCFG         0x60A
> > #define CSR_HENVCFGH        0x61A
> > 
> >+/* Hypervisor state CSRs */
> >+#define CSR_HSTATEEN0       0x60C
> >+#define CSR_HSTATEEN0H      0x61C
> >+#define CSR_HSTATEEN1       0x60D
> >+#define CSR_HSTATEEN1H      0x61D
> >+#define CSR_HSTATEEN2       0x60E
> >+#define CSR_HSTATEEN2H      0x61E
> >+#define CSR_HSTATEEN3       0x60F
> >+#define CSR_HSTATEEN3H      0x61F
> >+
> > /* Virtual CSRs */
> > #define CSR_VSSTATUS        0x200
> > #define CSR_VSIE            0x204
> >@@ -304,6 +320,26 @@
> > #define CSR_MENVCFG         0x30A
> > #define CSR_MENVCFGH        0x31A
> > 
> >+/* Machine state CSRs */
> >+#define CSR_MSTATEEN0       0x30C
> >+#define CSR_MSTATEEN0H      0x31C
> >+#define CSR_MSTATEEN1       0x30D
> >+#define CSR_MSTATEEN1H      0x31D
> >+#define CSR_MSTATEEN2       0x30E
> >+#define CSR_MSTATEEN2H      0x31E
> >+#define CSR_MSTATEEN3       0x30F
> >+#define CSR_MSTATEEN3H      0x31F
> >+
> >+/* Common defines for all smstateen */
> >+#define SMSTATEEN_MAX_COUNT 4
> >+#define SMSTATEEN0_CS       0
> >+#define SMSTATEEN0_FCSR     0
> >+#define SMSTATEEN0_IMSIC    58
> >+#define SMSTATEEN0_AIA      59
> >+#define SMSTATEEN0_SVSLCT   60
> >+#define SMSTATEEN0_HSENVCFG 62
> >+#define SMSTATEEN_STATEN    63
> >+
> > /* Enhanced Physical Memory Protection (ePMP) */
> > #define CSR_MSECCFG         0x747
> > #define CSR_MSECCFGH        0x757
> >diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> >index 409a209f14..324fefce59 100644
> >--- a/target/riscv/csr.c
> >+++ b/target/riscv/csr.c
> >@@ -247,6 +247,42 @@ static RISCVException hmode32(CPURISCVState
> *env, int csrno)
> > 
> > }
> > 
> >+static RISCVException mstateen(CPURISCVState *env, int csrno)
> >+{
> >+    CPUState *cs = env_cpu(env);
> >+    RISCVCPU *cpu = RISCV_CPU(cs);
> >+
> >+    if (!cpu->cfg.ext_smstateen) {
> >+        return RISCV_EXCP_ILLEGAL_INST;
> >+    }
> >+
> >+    return any(env, csrno);
> >+}
> >+
> >+static RISCVException hstateen(CPURISCVState *env, int csrno)
> >+{
> >+    CPUState *cs = env_cpu(env);
> >+    RISCVCPU *cpu = RISCV_CPU(cs);
> >+
> >+    if (!cpu->cfg.ext_smstateen) {
> >+        return RISCV_EXCP_ILLEGAL_INST;
> >+    }
> >+
> >+    return hmode(env, csrno);
> >+}
> >+
> 
> I think we should take the stateen bit(bit 63) for matching mstateen
> into consideration here. 
> Similar to following sstateen function.
ok.

> >+static RISCVException sstateen(CPURISCVState *env, int csrno)
> >+{
> >+    CPUState *cs = env_cpu(env);
> >+    RISCVCPU *cpu = RISCV_CPU(cs);
> >+
> >+    if (!cpu->cfg.ext_smstateen) {
> >+        return RISCV_EXCP_ILLEGAL_INST;
> >+    }
> >+
> >+    return smode(env, csrno);
> >+}
> >+
> > /* Checks if PointerMasking registers could be accessed */
> > static RISCVException pointer_masking(CPURISCVState *env, int
> csrno)
> > {
> >@@ -1574,6 +1610,129 @@ static RISCVException
> write_henvcfgh(CPURISCVState *env, int csrno,
> >     return RISCV_EXCP_NONE;
> > }
> > 
> >+static inline void write_smstateen(CPURISCVState *env, uint64_t
> *reg,
> >+                                   uint64_t wr_mask, uint64_t
> new_val)
> >+{
> >+    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
> >+}
> >+
> >+static RISCVException read_mstateen(CPURISCVState *env, int csrno,
> >+                                    target_ulong *val)
> >+{
> >+    *val = env->mstateen[csrno - CSR_MSTATEEN0];
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException write_mstateen(CPURISCVState *env, int csrno,
> >+                                     target_ulong new_val)
> >+{
> >+    uint64_t *reg;
> >+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+
> >+    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> >+    write_smstateen(env, reg, wr_mask, new_val);
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException read_mstateenh(CPURISCVState *env, int csrno,
> >+                                     target_ulong *val)
> >+{
> >+    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException write_mstateenh(CPURISCVState *env, int
> csrno,
> >+                                      target_ulong new_val)
> >+{
> >+    uint64_t *reg;
> >+    uint64_t val;
> >+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+
> >+    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> >+    val = (uint64_t)new_val << 32;
> >+    val |= *reg & 0xFFFFFFFF;
> >+    write_smstateen(env, reg, wr_mask, val);
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException read_hstateen(CPURISCVState *env, int csrno,
> >+                                    target_ulong *val)
> >+{
> >+    *val = env->hstateen[csrno - CSR_HSTATEEN0];
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> 
> I think we should also take mstateen into consideration here just
> like the following write function.
> As the spec said, If we set certain bit in the matching mstateen csr
> to zero, the same bit in hstateen should be read-only zero.
> However, writes to mstateen will not affect the value in matching
> hstateen directly in current implementation, 
> so if we read hstateen just immediately after write zero to certain
> bit of mstateen, the same bit  read from hstateen may not be zero.
I need to check this but as per my understanding this it is the
responsibility of the software to clear the corresponding
hstateen/stateen bits.
> 
> similar to read function of sstateen.
> >+static RISCVException write_hstateen(CPURISCVState *env, int csrno,
> >+                                     target_ulong new_val)
> >+{
> >+    uint64_t *reg;
> >+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+    int index = csrno - CSR_HSTATEEN0;
> >+
> >+    reg = &env->hstateen[index];
> >+    wr_mask &= env->mstateen[index];
> >+    write_smstateen(env, reg, wr_mask, new_val);
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException read_hstateenh(CPURISCVState *env, int csrno,
> >+                                     target_ulong *val)
> >+{
> >+    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException write_hstateenh(CPURISCVState *env, int
> csrno,
> >+                                      target_ulong new_val)
> >+{
> >+    uint64_t *reg;
> >+    uint64_t val;
> >+    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+    int index = csrno - CSR_HSTATEEN0H;
> >+
> >+    reg = &env->hstateen[index];
> >+    val = (uint64_t)new_val << 32;
> >+    val |= *reg & 0xFFFFFFFF;
> >+    wr_mask &= env->mstateen[index];
> >+
> >+    write_smstateen(env, reg, wr_mask, val);
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException read_sstateen(CPURISCVState *env, int csrno,
> >+                                    target_ulong *val)
> >+{
> >+    *val = env->sstateen[csrno - CSR_SSTATEEN0];
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> >+static RISCVException write_sstateen(CPURISCVState *env, int csrno,
> >+                                     target_ulong new_val)
> >+{
> >+    uint64_t *reg;
> >+    uint64_t wr_mask = 0;
> >+    int index = csrno - CSR_SSTATEEN0;
> >+    bool virt = riscv_cpu_virt_enabled(env);
> >+
> >+    reg = &env->sstateen[index];
> >+    if (virt) {
> >+        wr_mask &= env->mstateen[index];
> >+    } else {
> >+        wr_mask &= env->hstateen[index];
> >+    }
> Why this? I think hstateen works in virt mode, so this may be:
> if (virt) {
>   wr_mask &= env->mstateen[index] & env->hstateen[index];;
> } else {
>   wr_mask &= env->mstateen[index];
> }
> >+    write_smstateen(env, reg, wr_mask, new_val);
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> > static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
> >                                 uint64_t *ret_val,
> >                                 uint64_t new_val, uint64_t wr_mask)
> >@@ -3441,6 +3600,57 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE]
> = {
> >     [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh,
> write_henvcfgh,
> >                                           .min_priv_ver =
> PRIV_VERSION_1_12_0 },
> > 
> >+    /* Smstateen extension CSRs */
> >+    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen,
> write_mstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen, read_mstateenh,
> >+                          write_mstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen,
> write_mstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> 
> It seems unreasonable for mstateen1~3 to share the same read/write
> function with mstateen0 , 
> since their field mask is different.
> Similar to sstateen1~3 and hstateen1~3

I will fix it in the next version.
> 
> Regards,
> Weiwei Li
> >+    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen, read_mstateenh,
> >+                          write_mstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen,
> write_mstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen, read_mstateenh,
> >+                          write_mstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen,
> write_mstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen, read_mstateenh,
> >+                          write_mstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+
> >+    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen,
> write_hstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen, read_hstateenh,
> >+                          write_hstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen,
> write_hstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen, read_hstateenh,
> >+                          write_hstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen,
> write_hstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen, read_hstateenh,
> >+                          write_hstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen,
> write_hstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen, read_hstateenh,
> >+                          write_hstateenh,
> >+                          .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+
> >+    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen,
> write_sstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen,
> write_sstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen,
> write_sstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >+    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen,
> write_sstateen,
> >+                         .min_priv_ver = PRIV_VERSION_1_12_0 },
> >     /* Supervisor Trap Setup */
> >     [CSR_SSTATUS]    = { "sstatus",    smode,
> read_sstatus,    write_sstatus, NULL,
> >                                               read_sstatus_i128    
>              },
> >diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> >index 2a437b29a1..84a75dbb08 100644
> >--- a/target/riscv/machine.c
> >+++ b/target/riscv/machine.c
> >@@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void *opaque,
> int version_id)
> >     return 0;
> > }
> > 
> >+static bool smstateen_needed(void *opaque)
> >+{
> >+    RISCVCPU *cpu = opaque;
> >+
> >+    return cpu->cfg.ext_smstateen;
> >+}
> >+
> >+static const VMStateDescription vmstate_smstateen = {
> >+    .name = "cpu/smtateen",
> >+    .version_id = 1,
> >+    .minimum_version_id = 1,
> >+    .needed = smstateen_needed,
> >+    .fields = (VMStateField[]) {
> >+        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
> >+        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
> >+        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
> >+        VMSTATE_END_OF_LIST()
> >+    }
> >+};
> >+
> > static bool envcfg_needed(void *opaque)
> > {
> >     RISCVCPU *cpu = opaque;
> >@@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu = {
> >         &vmstate_kvmtimer,
> >         &vmstate_envcfg,
> >         &vmstate_debug,
> >+        &vmstate_smstateen,
> >         NULL
> >     }
> > };
> >-- 
> >2.25.1
> >

Re: [RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Weiwei Li]

在 2022/7/8 上午12:53, Mayuresh Chitale 写道:
> On Sat, 2022-07-02 at 18:19 +0800, angell1518 wrote:
>> At 2022-06-04 00:04:22, "Mayuresh Chitale" <mchitale@ventanamicro.com
>>> wrote:
>>> Smstateen extension specifies a mechanism to close
>>> the potential covert channels that could cause security issues.
>>>
>>> This patch adds the CSRs defined in the specification and
>>> the corresponding predicates and read/write functions.
>>>
>>> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
>>> ---
>>> target/riscv/cpu.c      |   2 +
>>> target/riscv/cpu.h      |   4 +
>>> target/riscv/cpu_bits.h |  36 +++++++
>>> target/riscv/csr.c      | 210
>> ++++++++++++++++++++++++++++++++++++++++
>>> target/riscv/machine.c  |  21 ++++
>>> 5 files changed, 273 insertions(+)
>>>
>>> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
>>> index e6e878ceb3..2d65ccd90f 100644
>>> --- a/target/riscv/cpu.c
>>> +++ b/target/riscv/cpu.c
>>> @@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
>>>      DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
>>>      DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
>>>      DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
>>> +    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen,
>> false),
>>>      DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
>>>      DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
>>> @@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU
>> *cpu, char **isa_str, int max_str_len)
>>>          ISA_EDATA_ENTRY(zve64f, ext_zve64f),
>>>          ISA_EDATA_ENTRY(zhinx, ext_zhinx),
>>>          ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
>>> +        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
>>>          ISA_EDATA_ENTRY(svinval, ext_svinval),
>>>          ISA_EDATA_ENTRY(svnapot, ext_svnapot),
>>>          ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
>>> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
>>> index f08c3e8813..1c269b77bd 100644
>>> --- a/target/riscv/cpu.h
>>> +++ b/target/riscv/cpu.h
>>> @@ -327,6 +327,9 @@ struct CPUArchState {
>>>
>>>      /* CSRs for execution enviornment configuration */
>>>      uint64_t menvcfg;
>>> +    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
>>> +    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
>>> +    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
>>>      target_ulong senvcfg;
>>>      uint64_t henvcfg;
>>> #endif
>>> @@ -411,6 +414,7 @@ struct RISCVCPUConfig {
>>>      bool ext_zhinxmin;
>>>      bool ext_zve32f;
>>>      bool ext_zve64f;
>>> +    bool ext_smstateen;
>>>
>>>      uint32_t mvendorid;
>>>      uint64_t marchid;
>>> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
>>> index 4a55c6a709..2a3ef26d21 100644
>>> --- a/target/riscv/cpu_bits.h
>>> +++ b/target/riscv/cpu_bits.h
>>> @@ -208,6 +208,12 @@
>>> /* Supervisor Configuration CSRs */
>>> #define CSR_SENVCFG         0x10A
>>>
>>> +/* Supervisor state CSRs */
>>> +#define CSR_SSTATEEN0       0x10C
>>> +#define CSR_SSTATEEN1       0x10D
>>> +#define CSR_SSTATEEN2       0x10E
>>> +#define CSR_SSTATEEN3       0x10F
>>> +
>>> /* Supervisor Trap Handling */
>>> #define CSR_SSCRATCH        0x140
>>> #define CSR_SEPC            0x141
>>> @@ -257,6 +263,16 @@
>>> #define CSR_HENVCFG         0x60A
>>> #define CSR_HENVCFGH        0x61A
>>>
>>> +/* Hypervisor state CSRs */
>>> +#define CSR_HSTATEEN0       0x60C
>>> +#define CSR_HSTATEEN0H      0x61C
>>> +#define CSR_HSTATEEN1       0x60D
>>> +#define CSR_HSTATEEN1H      0x61D
>>> +#define CSR_HSTATEEN2       0x60E
>>> +#define CSR_HSTATEEN2H      0x61E
>>> +#define CSR_HSTATEEN3       0x60F
>>> +#define CSR_HSTATEEN3H      0x61F
>>> +
>>> /* Virtual CSRs */
>>> #define CSR_VSSTATUS        0x200
>>> #define CSR_VSIE            0x204
>>> @@ -304,6 +320,26 @@
>>> #define CSR_MENVCFG         0x30A
>>> #define CSR_MENVCFGH        0x31A
>>>
>>> +/* Machine state CSRs */
>>> +#define CSR_MSTATEEN0       0x30C
>>> +#define CSR_MSTATEEN0H      0x31C
>>> +#define CSR_MSTATEEN1       0x30D
>>> +#define CSR_MSTATEEN1H      0x31D
>>> +#define CSR_MSTATEEN2       0x30E
>>> +#define CSR_MSTATEEN2H      0x31E
>>> +#define CSR_MSTATEEN3       0x30F
>>> +#define CSR_MSTATEEN3H      0x31F
>>> +
>>> +/* Common defines for all smstateen */
>>> +#define SMSTATEEN_MAX_COUNT 4
>>> +#define SMSTATEEN0_CS       0
>>> +#define SMSTATEEN0_FCSR     0
>>> +#define SMSTATEEN0_IMSIC    58
>>> +#define SMSTATEEN0_AIA      59
>>> +#define SMSTATEEN0_SVSLCT   60
>>> +#define SMSTATEEN0_HSENVCFG 62
>>> +#define SMSTATEEN_STATEN    63
>>> +
>>> /* Enhanced Physical Memory Protection (ePMP) */
>>> #define CSR_MSECCFG         0x747
>>> #define CSR_MSECCFGH        0x757
>>> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
>>> index 409a209f14..324fefce59 100644
>>> --- a/target/riscv/csr.c
>>> +++ b/target/riscv/csr.c
>>> @@ -247,6 +247,42 @@ static RISCVException hmode32(CPURISCVState
>> *env, int csrno)
>>> }
>>>
>>> +static RISCVException mstateen(CPURISCVState *env, int csrno)
>>> +{
>>> +    CPUState *cs = env_cpu(env);
>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>> +
>>> +    if (!cpu->cfg.ext_smstateen) {
>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>> +    }
>>> +
>>> +    return any(env, csrno);
>>> +}
>>> +
>>> +static RISCVException hstateen(CPURISCVState *env, int csrno)
>>> +{
>>> +    CPUState *cs = env_cpu(env);
>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>> +
>>> +    if (!cpu->cfg.ext_smstateen) {
>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>> +    }
>>> +
>>> +    return hmode(env, csrno);
>>> +}
>>> +
>> I think we should take the stateen bit(bit 63) for matching mstateen
>> into consideration here.
>> Similar to following sstateen function.
> ok.
>
>>> +static RISCVException sstateen(CPURISCVState *env, int csrno)
>>> +{
>>> +    CPUState *cs = env_cpu(env);
>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>> +
>>> +    if (!cpu->cfg.ext_smstateen) {
>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>> +    }
>>> +
>>> +    return smode(env, csrno);
>>> +}
>>> +
>>> /* Checks if PointerMasking registers could be accessed */
>>> static RISCVException pointer_masking(CPURISCVState *env, int
>> csrno)
>>> {
>>> @@ -1574,6 +1610,129 @@ static RISCVException
>> write_henvcfgh(CPURISCVState *env, int csrno,
>>>      return RISCV_EXCP_NONE;
>>> }
>>>
>>> +static inline void write_smstateen(CPURISCVState *env, uint64_t
>> *reg,
>>> +                                   uint64_t wr_mask, uint64_t
>> new_val)
>>> +{
>>> +    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
>>> +}
>>> +
>>> +static RISCVException read_mstateen(CPURISCVState *env, int csrno,
>>> +                                    target_ulong *val)
>>> +{
>>> +    *val = env->mstateen[csrno - CSR_MSTATEEN0];
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>>> +                                     target_ulong new_val)
>>> +{
>>> +    uint64_t *reg;
>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +
>>> +    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>>> +    write_smstateen(env, reg, wr_mask, new_val);
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException read_mstateenh(CPURISCVState *env, int csrno,
>>> +                                     target_ulong *val)
>>> +{
>>> +    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException write_mstateenh(CPURISCVState *env, int
>> csrno,
>>> +                                      target_ulong new_val)
>>> +{
>>> +    uint64_t *reg;
>>> +    uint64_t val;
>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +
>>> +    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>>> +    val = (uint64_t)new_val << 32;
>>> +    val |= *reg & 0xFFFFFFFF;
>>> +    write_smstateen(env, reg, wr_mask, val);
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException read_hstateen(CPURISCVState *env, int csrno,
>>> +                                    target_ulong *val)
>>> +{
>>> +    *val = env->hstateen[csrno - CSR_HSTATEEN0];
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>> I think we should also take mstateen into consideration here just
>> like the following write function.
>> As the spec said, If we set certain bit in the matching mstateen csr
>> to zero, the same bit in hstateen should be read-only zero.
>> However, writes to mstateen will not affect the value in matching
>> hstateen directly in current implementation,
>> so if we read hstateen just immediately after write zero to certain
>> bit of mstateen, the same bit  read from hstateen may not be zero.
> I need to check this but as per my understanding this it is the
> responsibility of the software to clear the corresponding
> hstateen/stateen bits.

I have sent a issue for how the hstateen/sstateen become read-only zero  
for zero bits in mstateen:

https://github.com/riscv/riscv-state-enable/issues/9

Regards,

Weiwei Li

>> similar to read function of sstateen.
>>> +static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>>> +                                     target_ulong new_val)
>>> +{
>>> +    uint64_t *reg;
>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +    int index = csrno - CSR_HSTATEEN0;
>>> +
>>> +    reg = &env->hstateen[index];
>>> +    wr_mask &= env->mstateen[index];
>>> +    write_smstateen(env, reg, wr_mask, new_val);
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException read_hstateenh(CPURISCVState *env, int csrno,
>>> +                                     target_ulong *val)
>>> +{
>>> +    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException write_hstateenh(CPURISCVState *env, int
>> csrno,
>>> +                                      target_ulong new_val)
>>> +{
>>> +    uint64_t *reg;
>>> +    uint64_t val;
>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +    int index = csrno - CSR_HSTATEEN0H;
>>> +
>>> +    reg = &env->hstateen[index];
>>> +    val = (uint64_t)new_val << 32;
>>> +    val |= *reg & 0xFFFFFFFF;
>>> +    wr_mask &= env->mstateen[index];
>>> +
>>> +    write_smstateen(env, reg, wr_mask, val);
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException read_sstateen(CPURISCVState *env, int csrno,
>>> +                                    target_ulong *val)
>>> +{
>>> +    *val = env->sstateen[csrno - CSR_SSTATEEN0];
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> +static RISCVException write_sstateen(CPURISCVState *env, int csrno,
>>> +                                     target_ulong new_val)
>>> +{
>>> +    uint64_t *reg;
>>> +    uint64_t wr_mask = 0;
>>> +    int index = csrno - CSR_SSTATEEN0;
>>> +    bool virt = riscv_cpu_virt_enabled(env);
>>> +
>>> +    reg = &env->sstateen[index];
>>> +    if (virt) {
>>> +        wr_mask &= env->mstateen[index];
>>> +    } else {
>>> +        wr_mask &= env->hstateen[index];
>>> +    }
>> Why this? I think hstateen works in virt mode, so this may be:
>> if (virt) {
>>    wr_mask &= env->mstateen[index] & env->hstateen[index];;
>> } else {
>>    wr_mask &= env->mstateen[index];
>> }
>>> +    write_smstateen(env, reg, wr_mask, new_val);
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
>>>                                  uint64_t *ret_val,
>>>                                  uint64_t new_val, uint64_t wr_mask)
>>> @@ -3441,6 +3600,57 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE]
>> = {
>>>      [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh,
>> write_henvcfgh,
>>>                                            .min_priv_ver =
>> PRIV_VERSION_1_12_0 },
>>> +    /* Smstateen extension CSRs */
>>> +    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen,
>> write_mstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen, read_mstateenh,
>>> +                          write_mstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen,
>> write_mstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>> It seems unreasonable for mstateen1~3 to share the same read/write
>> function with mstateen0 ,
>> since their field mask is different.
>> Similar to sstateen1~3 and hstateen1~3
> I will fix it in the next version.
>> Regards,
>> Weiwei Li
>>> +    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen, read_mstateenh,
>>> +                          write_mstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen,
>> write_mstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen, read_mstateenh,
>>> +                          write_mstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen,
>> write_mstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen, read_mstateenh,
>>> +                          write_mstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +
>>> +    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen,
>> write_hstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen, read_hstateenh,
>>> +                          write_hstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen,
>> write_hstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen, read_hstateenh,
>>> +                          write_hstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen,
>> write_hstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen, read_hstateenh,
>>> +                          write_hstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen,
>> write_hstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen, read_hstateenh,
>>> +                          write_hstateenh,
>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +
>>> +    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen,
>> write_sstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen,
>> write_sstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen,
>> write_sstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>> +    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen,
>> write_sstateen,
>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0 },
>>>      /* Supervisor Trap Setup */
>>>      [CSR_SSTATUS]    = { "sstatus",    smode,
>> read_sstatus,    write_sstatus, NULL,
>>>                                                read_sstatus_i128
>>               },
>>> diff --git a/target/riscv/machine.c b/target/riscv/machine.c
>>> index 2a437b29a1..84a75dbb08 100644
>>> --- a/target/riscv/machine.c
>>> +++ b/target/riscv/machine.c
>>> @@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void *opaque,
>> int version_id)
>>>      return 0;
>>> }
>>>
>>> +static bool smstateen_needed(void *opaque)
>>> +{
>>> +    RISCVCPU *cpu = opaque;
>>> +
>>> +    return cpu->cfg.ext_smstateen;
>>> +}
>>> +
>>> +static const VMStateDescription vmstate_smstateen = {
>>> +    .name = "cpu/smtateen",
>>> +    .version_id = 1,
>>> +    .minimum_version_id = 1,
>>> +    .needed = smstateen_needed,
>>> +    .fields = (VMStateField[]) {
>>> +        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
>>> +        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
>>> +        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
>>> +        VMSTATE_END_OF_LIST()
>>> +    }
>>> +};
>>> +
>>> static bool envcfg_needed(void *opaque)
>>> {
>>>      RISCVCPU *cpu = opaque;
>>> @@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu = {
>>>          &vmstate_kvmtimer,
>>>          &vmstate_envcfg,
>>>          &vmstate_debug,
>>> +        &vmstate_smstateen,
>>>          NULL
>>>      }
>>> };
>>> -- 
>>> 2.25.1
>>>

Re: [RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Mayuresh Chitale]

On Fri, 2022-07-08 at 07:44 +0800, Weiwei Li wrote:
> 在 2022/7/8 上午12:53, Mayuresh Chitale 写道:
> > On Sat, 2022-07-02 at 18:19 +0800, angell1518 wrote:
> > > At 2022-06-04 00:04:22, "Mayuresh Chitale" <
> > > mchitale@ventanamicro.com
> > > > wrote:
> > > > Smstateen extension specifies a mechanism to close
> > > > the potential covert channels that could cause security issues.
> > > > 
> > > > This patch adds the CSRs defined in the specification and
> > > > the corresponding predicates and read/write functions.
> > > > 
> > > > Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> > > > ---
> > > > target/riscv/cpu.c      |   2 +
> > > > target/riscv/cpu.h      |   4 +
> > > > target/riscv/cpu_bits.h |  36 +++++++
> > > > target/riscv/csr.c      | 210
> > > ++++++++++++++++++++++++++++++++++++++++
> > > > target/riscv/machine.c  |  21 ++++
> > > > 5 files changed, 273 insertions(+)
> > > > 
> > > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> > > > index e6e878ceb3..2d65ccd90f 100644
> > > > --- a/target/riscv/cpu.c
> > > > +++ b/target/riscv/cpu.c
> > > > @@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
> > > >      DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
> > > >      DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
> > > >      DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
> > > > +    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen,
> > > false),
> > > >      DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
> > > >      DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
> > > > @@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU
> > > *cpu, char **isa_str, int max_str_len)
> > > >          ISA_EDATA_ENTRY(zve64f, ext_zve64f),
> > > >          ISA_EDATA_ENTRY(zhinx, ext_zhinx),
> > > >          ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
> > > > +        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
> > > >          ISA_EDATA_ENTRY(svinval, ext_svinval),
> > > >          ISA_EDATA_ENTRY(svnapot, ext_svnapot),
> > > >          ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
> > > > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> > > > index f08c3e8813..1c269b77bd 100644
> > > > --- a/target/riscv/cpu.h
> > > > +++ b/target/riscv/cpu.h
> > > > @@ -327,6 +327,9 @@ struct CPUArchState {
> > > > 
> > > >      /* CSRs for execution enviornment configuration */
> > > >      uint64_t menvcfg;
> > > > +    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
> > > > +    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
> > > > +    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
> > > >      target_ulong senvcfg;
> > > >      uint64_t henvcfg;
> > > > #endif
> > > > @@ -411,6 +414,7 @@ struct RISCVCPUConfig {
> > > >      bool ext_zhinxmin;
> > > >      bool ext_zve32f;
> > > >      bool ext_zve64f;
> > > > +    bool ext_smstateen;
> > > > 
> > > >      uint32_t mvendorid;
> > > >      uint64_t marchid;
> > > > diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> > > > index 4a55c6a709..2a3ef26d21 100644
> > > > --- a/target/riscv/cpu_bits.h
> > > > +++ b/target/riscv/cpu_bits.h
> > > > @@ -208,6 +208,12 @@
> > > > /* Supervisor Configuration CSRs */
> > > > #define CSR_SENVCFG         0x10A
> > > > 
> > > > +/* Supervisor state CSRs */
> > > > +#define CSR_SSTATEEN0       0x10C
> > > > +#define CSR_SSTATEEN1       0x10D
> > > > +#define CSR_SSTATEEN2       0x10E
> > > > +#define CSR_SSTATEEN3       0x10F
> > > > +
> > > > /* Supervisor Trap Handling */
> > > > #define CSR_SSCRATCH        0x140
> > > > #define CSR_SEPC            0x141
> > > > @@ -257,6 +263,16 @@
> > > > #define CSR_HENVCFG         0x60A
> > > > #define CSR_HENVCFGH        0x61A
> > > > 
> > > > +/* Hypervisor state CSRs */
> > > > +#define CSR_HSTATEEN0       0x60C
> > > > +#define CSR_HSTATEEN0H      0x61C
> > > > +#define CSR_HSTATEEN1       0x60D
> > > > +#define CSR_HSTATEEN1H      0x61D
> > > > +#define CSR_HSTATEEN2       0x60E
> > > > +#define CSR_HSTATEEN2H      0x61E
> > > > +#define CSR_HSTATEEN3       0x60F
> > > > +#define CSR_HSTATEEN3H      0x61F
> > > > +
> > > > /* Virtual CSRs */
> > > > #define CSR_VSSTATUS        0x200
> > > > #define CSR_VSIE            0x204
> > > > @@ -304,6 +320,26 @@
> > > > #define CSR_MENVCFG         0x30A
> > > > #define CSR_MENVCFGH        0x31A
> > > > 
> > > > +/* Machine state CSRs */
> > > > +#define CSR_MSTATEEN0       0x30C
> > > > +#define CSR_MSTATEEN0H      0x31C
> > > > +#define CSR_MSTATEEN1       0x30D
> > > > +#define CSR_MSTATEEN1H      0x31D
> > > > +#define CSR_MSTATEEN2       0x30E
> > > > +#define CSR_MSTATEEN2H      0x31E
> > > > +#define CSR_MSTATEEN3       0x30F
> > > > +#define CSR_MSTATEEN3H      0x31F
> > > > +
> > > > +/* Common defines for all smstateen */
> > > > +#define SMSTATEEN_MAX_COUNT 4
> > > > +#define SMSTATEEN0_CS       0
> > > > +#define SMSTATEEN0_FCSR     0
> > > > +#define SMSTATEEN0_IMSIC    58
> > > > +#define SMSTATEEN0_AIA      59
> > > > +#define SMSTATEEN0_SVSLCT   60
> > > > +#define SMSTATEEN0_HSENVCFG 62
> > > > +#define SMSTATEEN_STATEN    63
> > > > +
> > > > /* Enhanced Physical Memory Protection (ePMP) */
> > > > #define CSR_MSECCFG         0x747
> > > > #define CSR_MSECCFGH        0x757
> > > > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > > > index 409a209f14..324fefce59 100644
> > > > --- a/target/riscv/csr.c
> > > > +++ b/target/riscv/csr.c
> > > > @@ -247,6 +247,42 @@ static RISCVException
> > > > hmode32(CPURISCVState
> > > *env, int csrno)
> > > > }
> > > > 
> > > > +static RISCVException mstateen(CPURISCVState *env, int csrno)
> > > > +{
> > > > +    CPUState *cs = env_cpu(env);
> > > > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > > > +
> > > > +    if (!cpu->cfg.ext_smstateen) {
> > > > +        return RISCV_EXCP_ILLEGAL_INST;
> > > > +    }
> > > > +
> > > > +    return any(env, csrno);
> > > > +}
> > > > +
> > > > +static RISCVException hstateen(CPURISCVState *env, int csrno)
> > > > +{
> > > > +    CPUState *cs = env_cpu(env);
> > > > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > > > +
> > > > +    if (!cpu->cfg.ext_smstateen) {
> > > > +        return RISCV_EXCP_ILLEGAL_INST;
> > > > +    }
> > > > +
> > > > +    return hmode(env, csrno);
> > > > +}
> > > > +
> > > I think we should take the stateen bit(bit 63) for matching
> > > mstateen
> > > into consideration here.
> > > Similar to following sstateen function.
> > ok.
> > 
> > > > +static RISCVException sstateen(CPURISCVState *env, int csrno)
> > > > +{
> > > > +    CPUState *cs = env_cpu(env);
> > > > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > > > +
> > > > +    if (!cpu->cfg.ext_smstateen) {
> > > > +        return RISCV_EXCP_ILLEGAL_INST;
> > > > +    }
> > > > +
> > > > +    return smode(env, csrno);
> > > > +}
> > > > +
> > > > /* Checks if PointerMasking registers could be accessed */
> > > > static RISCVException pointer_masking(CPURISCVState *env, int
> > > csrno)
> > > > {
> > > > @@ -1574,6 +1610,129 @@ static RISCVException
> > > write_henvcfgh(CPURISCVState *env, int csrno,
> > > >      return RISCV_EXCP_NONE;
> > > > }
> > > > 
> > > > +static inline void write_smstateen(CPURISCVState *env,
> > > > uint64_t
> > > *reg,
> > > > +                                   uint64_t wr_mask, uint64_t
> > > new_val)
> > > > +{
> > > > +    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
> > > > +}
> > > > +
> > > > +static RISCVException read_mstateen(CPURISCVState *env, int
> > > > csrno,
> > > > +                                    target_ulong *val)
> > > > +{
> > > > +    *val = env->mstateen[csrno - CSR_MSTATEEN0];
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException write_mstateen(CPURISCVState *env, int
> > > > csrno,
> > > > +                                     target_ulong new_val)
> > > > +{
> > > > +    uint64_t *reg;
> > > > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > > > +
> > > > +    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> > > > +    write_smstateen(env, reg, wr_mask, new_val);
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException read_mstateenh(CPURISCVState *env, int
> > > > csrno,
> > > > +                                     target_ulong *val)
> > > > +{
> > > > +    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException write_mstateenh(CPURISCVState *env, int
> > > csrno,
> > > > +                                      target_ulong new_val)
> > > > +{
> > > > +    uint64_t *reg;
> > > > +    uint64_t val;
> > > > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > > > +
> > > > +    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> > > > +    val = (uint64_t)new_val << 32;
> > > > +    val |= *reg & 0xFFFFFFFF;
> > > > +    write_smstateen(env, reg, wr_mask, val);
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException read_hstateen(CPURISCVState *env, int
> > > > csrno,
> > > > +                                    target_ulong *val)
> > > > +{
> > > > +    *val = env->hstateen[csrno - CSR_HSTATEEN0];
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > I think we should also take mstateen into consideration here just
> > > like the following write function.
> > > As the spec said, If we set certain bit in the matching mstateen
> > > csr
> > > to zero, the same bit in hstateen should be read-only zero.
> > > However, writes to mstateen will not affect the value in matching
> > > hstateen directly in current implementation,
> > > so if we read hstateen just immediately after write zero to
> > > certain
> > > bit of mstateen, the same bit  read from hstateen may not be
> > > zero.
> > I need to check this but as per my understanding this it is the
> > responsibility of the software to clear the corresponding
> > hstateen/stateen bits.
> 
> I have sent a issue for how the hstateen/sstateen become read-only
> zero  
> for zero bits in mstateen:
> 
> https://github.com/riscv/riscv-state-enable/issues/9

Thanks for the information. I think as per the dicussion on the above
issue it looks like the current implementation is also valid.
> 
> Regards,
> 
> Weiwei Li
> 
> > > similar to read function of sstateen.
> > > > +static RISCVException write_hstateen(CPURISCVState *env, int
> > > > csrno,
> > > > +                                     target_ulong new_val)
> > > > +{
> > > > +    uint64_t *reg;
> > > > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > > > +    int index = csrno - CSR_HSTATEEN0;
> > > > +
> > > > +    reg = &env->hstateen[index];
> > > > +    wr_mask &= env->mstateen[index];
> > > > +    write_smstateen(env, reg, wr_mask, new_val);
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException read_hstateenh(CPURISCVState *env, int
> > > > csrno,
> > > > +                                     target_ulong *val)
> > > > +{
> > > > +    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException write_hstateenh(CPURISCVState *env, int
> > > csrno,
> > > > +                                      target_ulong new_val)
> > > > +{
> > > > +    uint64_t *reg;
> > > > +    uint64_t val;
> > > > +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > > > +    int index = csrno - CSR_HSTATEEN0H;
> > > > +
> > > > +    reg = &env->hstateen[index];
> > > > +    val = (uint64_t)new_val << 32;
> > > > +    val |= *reg & 0xFFFFFFFF;
> > > > +    wr_mask &= env->mstateen[index];
> > > > +
> > > > +    write_smstateen(env, reg, wr_mask, val);
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException read_sstateen(CPURISCVState *env, int
> > > > csrno,
> > > > +                                    target_ulong *val)
> > > > +{
> > > > +    *val = env->sstateen[csrno - CSR_SSTATEEN0];
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > +static RISCVException write_sstateen(CPURISCVState *env, int
> > > > csrno,
> > > > +                                     target_ulong new_val)
> > > > +{
> > > > +    uint64_t *reg;
> > > > +    uint64_t wr_mask = 0;
> > > > +    int index = csrno - CSR_SSTATEEN0;
> > > > +    bool virt = riscv_cpu_virt_enabled(env);
> > > > +
> > > > +    reg = &env->sstateen[index];
> > > > +    if (virt) {
> > > > +        wr_mask &= env->mstateen[index];
> > > > +    } else {
> > > > +        wr_mask &= env->hstateen[index];
> > > > +    }
> > > Why this? I think hstateen works in virt mode, so this may be:
> > > if (virt) {
> > >    wr_mask &= env->mstateen[index] & env->hstateen[index];;
> > > } else {
> > >    wr_mask &= env->mstateen[index];
> > > }
> > > > +    write_smstateen(env, reg, wr_mask, new_val);
> > > > +
> > > > +    return RISCV_EXCP_NONE;
> > > > +}
> > > > +
> > > > static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
> > > >                                  uint64_t *ret_val,
> > > >                                  uint64_t new_val, uint64_t
> > > > wr_mask)
> > > > @@ -3441,6 +3600,57 @@ riscv_csr_operations
> > > > csr_ops[CSR_TABLE_SIZE]
> > > = {
> > > >      [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh,
> > > write_henvcfgh,
> > > >                                            .min_priv_ver =
> > > PRIV_VERSION_1_12_0 },
> > > > +    /* Smstateen extension CSRs */
> > > > +    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen,
> > > write_mstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen,
> > > > read_mstateenh,
> > > > +                          write_mstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen,
> > > write_mstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > It seems unreasonable for mstateen1~3 to share the same
> > > read/write
> > > function with mstateen0 ,
> > > since their field mask is different.
> > > Similar to sstateen1~3 and hstateen1~3
> > I will fix it in the next version.
> > > Regards,
> > > Weiwei Li
> > > > +    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen,
> > > > read_mstateenh,
> > > > +                          write_mstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen,
> > > write_mstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen,
> > > > read_mstateenh,
> > > > +                          write_mstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen,
> > > write_mstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen,
> > > > read_mstateenh,
> > > > +                          write_mstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +
> > > > +    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen,
> > > write_hstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen,
> > > > read_hstateenh,
> > > > +                          write_hstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen,
> > > write_hstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen,
> > > > read_hstateenh,
> > > > +                          write_hstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen,
> > > write_hstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen,
> > > > read_hstateenh,
> > > > +                          write_hstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen,
> > > write_hstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen,
> > > > read_hstateenh,
> > > > +                          write_hstateenh,
> > > > +                          .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +
> > > > +    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen,
> > > write_sstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen,
> > > write_sstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen,
> > > write_sstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > > +    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen,
> > > write_sstateen,
> > > > +                         .min_priv_ver = PRIV_VERSION_1_12_0
> > > > },
> > > >      /* Supervisor Trap Setup */
> > > >      [CSR_SSTATUS]    = { "sstatus",    smode,
> > > read_sstatus,    write_sstatus, NULL,
> > > >                                                read_sstatus_i12
> > > > 8
> > >               },
> > > > diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> > > > index 2a437b29a1..84a75dbb08 100644
> > > > --- a/target/riscv/machine.c
> > > > +++ b/target/riscv/machine.c
> > > > @@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void
> > > > *opaque,
> > > int version_id)
> > > >      return 0;
> > > > }
> > > > 
> > > > +static bool smstateen_needed(void *opaque)
> > > > +{
> > > > +    RISCVCPU *cpu = opaque;
> > > > +
> > > > +    return cpu->cfg.ext_smstateen;
> > > > +}
> > > > +
> > > > +static const VMStateDescription vmstate_smstateen = {
> > > > +    .name = "cpu/smtateen",
> > > > +    .version_id = 1,
> > > > +    .minimum_version_id = 1,
> > > > +    .needed = smstateen_needed,
> > > > +    .fields = (VMStateField[]) {
> > > > +        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
> > > > +        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
> > > > +        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
> > > > +        VMSTATE_END_OF_LIST()
> > > > +    }
> > > > +};
> > > > +
> > > > static bool envcfg_needed(void *opaque)
> > > > {
> > > >      RISCVCPU *cpu = opaque;
> > > > @@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu
> > > > = {
> > > >          &vmstate_kvmtimer,
> > > >          &vmstate_envcfg,
> > > >          &vmstate_debug,
> > > > +        &vmstate_smstateen,
> > > >          NULL
> > > >      }
> > > > };
> > > > -- 
> > > > 2.25.1
> > > > 

Re: [RFC PATCH v5 1/4] target/riscv: Add smstateen support

[Weiwei Li]

在 2022/7/18 下午11:37, Mayuresh Chitale 写道:
> On Fri, 2022-07-08 at 07:44 +0800, Weiwei Li wrote:
>> 在 2022/7/8 上午12:53, Mayuresh Chitale 写道:
>>> On Sat, 2022-07-02 at 18:19 +0800, angell1518 wrote:
>>>> At 2022-06-04 00:04:22, "Mayuresh Chitale" <
>>>> mchitale@ventanamicro.com
>>>>> wrote:
>>>>> Smstateen extension specifies a mechanism to close
>>>>> the potential covert channels that could cause security issues.
>>>>>
>>>>> This patch adds the CSRs defined in the specification and
>>>>> the corresponding predicates and read/write functions.
>>>>>
>>>>> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
>>>>> ---
>>>>> target/riscv/cpu.c      |   2 +
>>>>> target/riscv/cpu.h      |   4 +
>>>>> target/riscv/cpu_bits.h |  36 +++++++
>>>>> target/riscv/csr.c      | 210
>>>> ++++++++++++++++++++++++++++++++++++++++
>>>>> target/riscv/machine.c  |  21 ++++
>>>>> 5 files changed, 273 insertions(+)
>>>>>
>>>>> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
>>>>> index e6e878ceb3..2d65ccd90f 100644
>>>>> --- a/target/riscv/cpu.c
>>>>> +++ b/target/riscv/cpu.c
>>>>> @@ -913,6 +913,7 @@ static Property riscv_cpu_properties[] = {
>>>>>       DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
>>>>>       DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
>>>>>       DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
>>>>> +    DEFINE_PROP_BOOL("smstateen", RISCVCPU, cfg.ext_smstateen,
>>>> false),
>>>>>       DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
>>>>>       DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
>>>>> @@ -1104,6 +1105,7 @@ static void riscv_isa_string_ext(RISCVCPU
>>>> *cpu, char **isa_str, int max_str_len)
>>>>>           ISA_EDATA_ENTRY(zve64f, ext_zve64f),
>>>>>           ISA_EDATA_ENTRY(zhinx, ext_zhinx),
>>>>>           ISA_EDATA_ENTRY(zhinxmin, ext_zhinxmin),
>>>>> +        ISA_EDATA_ENTRY(smstateen, ext_smstateen),
>>>>>           ISA_EDATA_ENTRY(svinval, ext_svinval),
>>>>>           ISA_EDATA_ENTRY(svnapot, ext_svnapot),
>>>>>           ISA_EDATA_ENTRY(svpbmt, ext_svpbmt),
>>>>> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
>>>>> index f08c3e8813..1c269b77bd 100644
>>>>> --- a/target/riscv/cpu.h
>>>>> +++ b/target/riscv/cpu.h
>>>>> @@ -327,6 +327,9 @@ struct CPUArchState {
>>>>>
>>>>>       /* CSRs for execution enviornment configuration */
>>>>>       uint64_t menvcfg;
>>>>> +    uint64_t mstateen[SMSTATEEN_MAX_COUNT];
>>>>> +    uint64_t hstateen[SMSTATEEN_MAX_COUNT];
>>>>> +    uint64_t sstateen[SMSTATEEN_MAX_COUNT];
>>>>>       target_ulong senvcfg;
>>>>>       uint64_t henvcfg;
>>>>> #endif
>>>>> @@ -411,6 +414,7 @@ struct RISCVCPUConfig {
>>>>>       bool ext_zhinxmin;
>>>>>       bool ext_zve32f;
>>>>>       bool ext_zve64f;
>>>>> +    bool ext_smstateen;
>>>>>
>>>>>       uint32_t mvendorid;
>>>>>       uint64_t marchid;
>>>>> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
>>>>> index 4a55c6a709..2a3ef26d21 100644
>>>>> --- a/target/riscv/cpu_bits.h
>>>>> +++ b/target/riscv/cpu_bits.h
>>>>> @@ -208,6 +208,12 @@
>>>>> /* Supervisor Configuration CSRs */
>>>>> #define CSR_SENVCFG         0x10A
>>>>>
>>>>> +/* Supervisor state CSRs */
>>>>> +#define CSR_SSTATEEN0       0x10C
>>>>> +#define CSR_SSTATEEN1       0x10D
>>>>> +#define CSR_SSTATEEN2       0x10E
>>>>> +#define CSR_SSTATEEN3       0x10F
>>>>> +
>>>>> /* Supervisor Trap Handling */
>>>>> #define CSR_SSCRATCH        0x140
>>>>> #define CSR_SEPC            0x141
>>>>> @@ -257,6 +263,16 @@
>>>>> #define CSR_HENVCFG         0x60A
>>>>> #define CSR_HENVCFGH        0x61A
>>>>>
>>>>> +/* Hypervisor state CSRs */
>>>>> +#define CSR_HSTATEEN0       0x60C
>>>>> +#define CSR_HSTATEEN0H      0x61C
>>>>> +#define CSR_HSTATEEN1       0x60D
>>>>> +#define CSR_HSTATEEN1H      0x61D
>>>>> +#define CSR_HSTATEEN2       0x60E
>>>>> +#define CSR_HSTATEEN2H      0x61E
>>>>> +#define CSR_HSTATEEN3       0x60F
>>>>> +#define CSR_HSTATEEN3H      0x61F
>>>>> +
>>>>> /* Virtual CSRs */
>>>>> #define CSR_VSSTATUS        0x200
>>>>> #define CSR_VSIE            0x204
>>>>> @@ -304,6 +320,26 @@
>>>>> #define CSR_MENVCFG         0x30A
>>>>> #define CSR_MENVCFGH        0x31A
>>>>>
>>>>> +/* Machine state CSRs */
>>>>> +#define CSR_MSTATEEN0       0x30C
>>>>> +#define CSR_MSTATEEN0H      0x31C
>>>>> +#define CSR_MSTATEEN1       0x30D
>>>>> +#define CSR_MSTATEEN1H      0x31D
>>>>> +#define CSR_MSTATEEN2       0x30E
>>>>> +#define CSR_MSTATEEN2H      0x31E
>>>>> +#define CSR_MSTATEEN3       0x30F
>>>>> +#define CSR_MSTATEEN3H      0x31F
>>>>> +
>>>>> +/* Common defines for all smstateen */
>>>>> +#define SMSTATEEN_MAX_COUNT 4
>>>>> +#define SMSTATEEN0_CS       0
>>>>> +#define SMSTATEEN0_FCSR     0
>>>>> +#define SMSTATEEN0_IMSIC    58
>>>>> +#define SMSTATEEN0_AIA      59
>>>>> +#define SMSTATEEN0_SVSLCT   60
>>>>> +#define SMSTATEEN0_HSENVCFG 62
>>>>> +#define SMSTATEEN_STATEN    63
>>>>> +
>>>>> /* Enhanced Physical Memory Protection (ePMP) */
>>>>> #define CSR_MSECCFG         0x747
>>>>> #define CSR_MSECCFGH        0x757
>>>>> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
>>>>> index 409a209f14..324fefce59 100644
>>>>> --- a/target/riscv/csr.c
>>>>> +++ b/target/riscv/csr.c
>>>>> @@ -247,6 +247,42 @@ static RISCVException
>>>>> hmode32(CPURISCVState
>>>> *env, int csrno)
>>>>> }
>>>>>
>>>>> +static RISCVException mstateen(CPURISCVState *env, int csrno)
>>>>> +{
>>>>> +    CPUState *cs = env_cpu(env);
>>>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>>>> +
>>>>> +    if (!cpu->cfg.ext_smstateen) {
>>>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>>>> +    }
>>>>> +
>>>>> +    return any(env, csrno);
>>>>> +}
>>>>> +
>>>>> +static RISCVException hstateen(CPURISCVState *env, int csrno)
>>>>> +{
>>>>> +    CPUState *cs = env_cpu(env);
>>>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>>>> +
>>>>> +    if (!cpu->cfg.ext_smstateen) {
>>>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>>>> +    }
>>>>> +
>>>>> +    return hmode(env, csrno);
>>>>> +}
>>>>> +
>>>> I think we should take the stateen bit(bit 63) for matching
>>>> mstateen
>>>> into consideration here.
>>>> Similar to following sstateen function.
>>> ok.
>>>
>>>>> +static RISCVException sstateen(CPURISCVState *env, int csrno)
>>>>> +{
>>>>> +    CPUState *cs = env_cpu(env);
>>>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>>>> +
>>>>> +    if (!cpu->cfg.ext_smstateen) {
>>>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>>>> +    }
>>>>> +
>>>>> +    return smode(env, csrno);
>>>>> +}
>>>>> +
>>>>> /* Checks if PointerMasking registers could be accessed */
>>>>> static RISCVException pointer_masking(CPURISCVState *env, int
>>>> csrno)
>>>>> {
>>>>> @@ -1574,6 +1610,129 @@ static RISCVException
>>>> write_henvcfgh(CPURISCVState *env, int csrno,
>>>>>       return RISCV_EXCP_NONE;
>>>>> }
>>>>>
>>>>> +static inline void write_smstateen(CPURISCVState *env,
>>>>> uint64_t
>>>> *reg,
>>>>> +                                   uint64_t wr_mask, uint64_t
>>>> new_val)
>>>>> +{
>>>>> +    *reg = (*reg & ~wr_mask) | (new_val & wr_mask);
>>>>> +}
>>>>> +
>>>>> +static RISCVException read_mstateen(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                    target_ulong *val)
>>>>> +{
>>>>> +    *val = env->mstateen[csrno - CSR_MSTATEEN0];
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException write_mstateen(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                     target_ulong new_val)
>>>>> +{
>>>>> +    uint64_t *reg;
>>>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>>>> +
>>>>> +    reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>>>>> +    write_smstateen(env, reg, wr_mask, new_val);
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException read_mstateenh(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                     target_ulong *val)
>>>>> +{
>>>>> +    *val = env->mstateen[csrno - CSR_MSTATEEN0H] >> 32;
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException write_mstateenh(CPURISCVState *env, int
>>>> csrno,
>>>>> +                                      target_ulong new_val)
>>>>> +{
>>>>> +    uint64_t *reg;
>>>>> +    uint64_t val;
>>>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>>>> +
>>>>> +    reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>>>>> +    val = (uint64_t)new_val << 32;
>>>>> +    val |= *reg & 0xFFFFFFFF;
>>>>> +    write_smstateen(env, reg, wr_mask, val);
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException read_hstateen(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                    target_ulong *val)
>>>>> +{
>>>>> +    *val = env->hstateen[csrno - CSR_HSTATEEN0];
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>> I think we should also take mstateen into consideration here just
>>>> like the following write function.
>>>> As the spec said, If we set certain bit in the matching mstateen
>>>> csr
>>>> to zero, the same bit in hstateen should be read-only zero.
>>>> However, writes to mstateen will not affect the value in matching
>>>> hstateen directly in current implementation,
>>>> so if we read hstateen just immediately after write zero to
>>>> certain
>>>> bit of mstateen, the same bit  read from hstateen may not be
>>>> zero.
>>> I need to check this but as per my understanding this it is the
>>> responsibility of the software to clear the corresponding
>>> hstateen/stateen bits.
>> I have sent a issue for how the hstateen/sstateen become read-only
>> zero
>> for zero bits in mstateen:
>>
>> https://github.com/riscv/riscv-state-enable/issues/9
> Thanks for the information. I think as per the dicussion on the above
> issue it looks like the current implementation is also valid.

I think the way to implement the read-only zero is unspecified. However, 
the read out value  for

the read-only zero fields  should be zero.

Regards,

Weiwei Li

>> Regards,
>>
>> Weiwei Li
>>
>>>> similar to read function of sstateen.
>>>>> +static RISCVException write_hstateen(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                     target_ulong new_val)
>>>>> +{
>>>>> +    uint64_t *reg;
>>>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>>>> +    int index = csrno - CSR_HSTATEEN0;
>>>>> +
>>>>> +    reg = &env->hstateen[index];
>>>>> +    wr_mask &= env->mstateen[index];
>>>>> +    write_smstateen(env, reg, wr_mask, new_val);
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException read_hstateenh(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                     target_ulong *val)
>>>>> +{
>>>>> +    *val = env->hstateen[csrno - CSR_HSTATEEN0H] >> 32;
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException write_hstateenh(CPURISCVState *env, int
>>>> csrno,
>>>>> +                                      target_ulong new_val)
>>>>> +{
>>>>> +    uint64_t *reg;
>>>>> +    uint64_t val;
>>>>> +    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>>>> +    int index = csrno - CSR_HSTATEEN0H;
>>>>> +
>>>>> +    reg = &env->hstateen[index];
>>>>> +    val = (uint64_t)new_val << 32;
>>>>> +    val |= *reg & 0xFFFFFFFF;
>>>>> +    wr_mask &= env->mstateen[index];
>>>>> +
>>>>> +    write_smstateen(env, reg, wr_mask, val);
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException read_sstateen(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                    target_ulong *val)
>>>>> +{
>>>>> +    *val = env->sstateen[csrno - CSR_SSTATEEN0];
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> +static RISCVException write_sstateen(CPURISCVState *env, int
>>>>> csrno,
>>>>> +                                     target_ulong new_val)
>>>>> +{
>>>>> +    uint64_t *reg;
>>>>> +    uint64_t wr_mask = 0;
>>>>> +    int index = csrno - CSR_SSTATEEN0;
>>>>> +    bool virt = riscv_cpu_virt_enabled(env);
>>>>> +
>>>>> +    reg = &env->sstateen[index];
>>>>> +    if (virt) {
>>>>> +        wr_mask &= env->mstateen[index];
>>>>> +    } else {
>>>>> +        wr_mask &= env->hstateen[index];
>>>>> +    }
>>>> Why this? I think hstateen works in virt mode, so this may be:
>>>> if (virt) {
>>>>     wr_mask &= env->mstateen[index] & env->hstateen[index];;
>>>> } else {
>>>>     wr_mask &= env->mstateen[index];
>>>> }
>>>>> +    write_smstateen(env, reg, wr_mask, new_val);
>>>>> +
>>>>> +    return RISCV_EXCP_NONE;
>>>>> +}
>>>>> +
>>>>> static RISCVException rmw_mip64(CPURISCVState *env, int csrno,
>>>>>                                   uint64_t *ret_val,
>>>>>                                   uint64_t new_val, uint64_t
>>>>> wr_mask)
>>>>> @@ -3441,6 +3600,57 @@ riscv_csr_operations
>>>>> csr_ops[CSR_TABLE_SIZE]
>>>> = {
>>>>>       [CSR_HENVCFGH] = { "henvcfgh", hmode32, read_henvcfgh,
>>>> write_henvcfgh,
>>>>>                                             .min_priv_ver =
>>>> PRIV_VERSION_1_12_0 },
>>>>> +    /* Smstateen extension CSRs */
>>>>> +    [CSR_MSTATEEN0] = { "mstateen0", mstateen, read_mstateen,
>>>> write_mstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_MSTATEEN0H] = { "mstateen0h", mstateen,
>>>>> read_mstateenh,
>>>>> +                          write_mstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_MSTATEEN1] = { "mstateen1", mstateen, read_mstateen,
>>>> write_mstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>> It seems unreasonable for mstateen1~3 to share the same
>>>> read/write
>>>> function with mstateen0 ,
>>>> since their field mask is different.
>>>> Similar to sstateen1~3 and hstateen1~3
>>> I will fix it in the next version.
>>>> Regards,
>>>> Weiwei Li
>>>>> +    [CSR_MSTATEEN1H] = { "mstateen1h", mstateen,
>>>>> read_mstateenh,
>>>>> +                          write_mstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_MSTATEEN2] = { "mstateen2", mstateen, read_mstateen,
>>>> write_mstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_MSTATEEN2H] = { "mstateen2h", mstateen,
>>>>> read_mstateenh,
>>>>> +                          write_mstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_MSTATEEN3] = { "mstateen3", mstateen, read_mstateen,
>>>> write_mstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_MSTATEEN3H] = { "mstateen3h", mstateen,
>>>>> read_mstateenh,
>>>>> +                          write_mstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +
>>>>> +    [CSR_HSTATEEN0] = { "hstateen0", hstateen, read_hstateen,
>>>> write_hstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN0H] = { "hstateen0h", hstateen,
>>>>> read_hstateenh,
>>>>> +                          write_hstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN1] = { "hstateen1", hstateen, read_hstateen,
>>>> write_hstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN1H] = { "hstateen1h", hstateen,
>>>>> read_hstateenh,
>>>>> +                          write_hstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN2] = { "hstateen2", hstateen, read_hstateen,
>>>> write_hstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN2H] = { "hstateen2h", hstateen,
>>>>> read_hstateenh,
>>>>> +                          write_hstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN3] = { "hstateen3", hstateen, read_hstateen,
>>>> write_hstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_HSTATEEN3H] = { "hstateen3h", hstateen,
>>>>> read_hstateenh,
>>>>> +                          write_hstateenh,
>>>>> +                          .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +
>>>>> +    [CSR_SSTATEEN0] = { "sstateen0", sstateen, read_sstateen,
>>>> write_sstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_SSTATEEN1] = { "sstateen1", sstateen, read_sstateen,
>>>> write_sstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_SSTATEEN2] = { "sstateen2", sstateen, read_sstateen,
>>>> write_sstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>> +    [CSR_SSTATEEN3] = { "sstateen3", sstateen, read_sstateen,
>>>> write_sstateen,
>>>>> +                         .min_priv_ver = PRIV_VERSION_1_12_0
>>>>> },
>>>>>       /* Supervisor Trap Setup */
>>>>>       [CSR_SSTATUS]    = { "sstatus",    smode,
>>>> read_sstatus,    write_sstatus, NULL,
>>>>>                                                 read_sstatus_i12
>>>>> 8
>>>>                },
>>>>> diff --git a/target/riscv/machine.c b/target/riscv/machine.c
>>>>> index 2a437b29a1..84a75dbb08 100644
>>>>> --- a/target/riscv/machine.c
>>>>> +++ b/target/riscv/machine.c
>>>>> @@ -262,6 +262,26 @@ static int riscv_cpu_post_load(void
>>>>> *opaque,
>>>> int version_id)
>>>>>       return 0;
>>>>> }
>>>>>
>>>>> +static bool smstateen_needed(void *opaque)
>>>>> +{
>>>>> +    RISCVCPU *cpu = opaque;
>>>>> +
>>>>> +    return cpu->cfg.ext_smstateen;
>>>>> +}
>>>>> +
>>>>> +static const VMStateDescription vmstate_smstateen = {
>>>>> +    .name = "cpu/smtateen",
>>>>> +    .version_id = 1,
>>>>> +    .minimum_version_id = 1,
>>>>> +    .needed = smstateen_needed,
>>>>> +    .fields = (VMStateField[]) {
>>>>> +        VMSTATE_UINT64_ARRAY(env.mstateen, RISCVCPU, 4),
>>>>> +        VMSTATE_UINT64_ARRAY(env.hstateen, RISCVCPU, 4),
>>>>> +        VMSTATE_UINT64_ARRAY(env.sstateen, RISCVCPU, 4),
>>>>> +        VMSTATE_END_OF_LIST()
>>>>> +    }
>>>>> +};
>>>>> +
>>>>> static bool envcfg_needed(void *opaque)
>>>>> {
>>>>>       RISCVCPU *cpu = opaque;
>>>>> @@ -347,6 +367,7 @@ const VMStateDescription vmstate_riscv_cpu
>>>>> = {
>>>>>           &vmstate_kvmtimer,
>>>>>           &vmstate_envcfg,
>>>>>           &vmstate_debug,
>>>>> +        &vmstate_smstateen,
>>>>>           NULL
>>>>>       }
>>>>> };
>>>>> -- 
>>>>> 2.25.1
>>>>>

[RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[Mayuresh Chitale]

Accesses to henvcfg, henvcfgh and senvcfg are allowed
only if corresponding bit in mstateen0/hstateen0 is
enabled. Otherwise an illegal instruction trap is
generated.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
---
 target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 78 insertions(+), 6 deletions(-)

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 324fefce59..ae91ae1f7e 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
 }
 
 /* Predicates */
+static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
+{
+    CPUState *cs = env_cpu(env);
+    RISCVCPU *cpu = RISCV_CPU(cs);
+    bool virt = riscv_cpu_virt_enabled(env);
+
+    if (!cpu->cfg.ext_smstateen) {
+        return RISCV_EXCP_NONE;
+    }
+
+#if !defined(CONFIG_USER_ONLY)
+    if (!(env->mstateen[0] & 1UL << bit)) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    if (virt) {
+        if (!(env->hstateen[0] & 1UL << bit)) {
+            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
+        }
+    }
+
+    if (mode == PRV_U) {
+        if (!(env->sstateen[0] & 1UL << bit)) {
+            return RISCV_EXCP_ILLEGAL_INST;
+        }
+    }
+#endif
+
+    return RISCV_EXCP_NONE;
+}
+
 static RISCVException fs(CPURISCVState *env, int csrno)
 {
 #if !defined(CONFIG_USER_ONLY)
@@ -1557,6 +1588,13 @@ static RISCVException write_menvcfgh(CPURISCVState *env, int csrno,
 static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
                                  target_ulong *val)
 {
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     *val = env->senvcfg;
     return RISCV_EXCP_NONE;
 }
@@ -1565,15 +1603,27 @@ static RISCVException write_senvcfg(CPURISCVState *env, int csrno,
                                   target_ulong val)
 {
     uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE | SENVCFG_CBZE;
+    RISCVException ret;
 
-    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
 
+    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
     return RISCV_EXCP_NONE;
 }
 
 static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
                                  target_ulong *val)
 {
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     *val = env->henvcfg;
     return RISCV_EXCP_NONE;
 }
@@ -1582,6 +1632,12 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
                                   target_ulong val)
 {
     uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE | HENVCFG_CBZE;
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
 
     if (riscv_cpu_mxl(env) == MXL_RV64) {
         mask |= HENVCFG_PBMTE | HENVCFG_STCE;
@@ -1595,6 +1651,13 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
 static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
                                  target_ulong *val)
 {
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     *val = env->henvcfg >> 32;
     return RISCV_EXCP_NONE;
 }
@@ -1604,9 +1667,14 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
 {
     uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
     uint64_t valh = (uint64_t)val << 32;
+    RISCVException ret;
 
-    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
 
+    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
     return RISCV_EXCP_NONE;
 }
 
@@ -1628,7 +1696,8 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
                                      target_ulong new_val)
 {
     uint64_t *reg;
-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
+                       (1UL << SMSTATEEN0_HSENVCFG);
 
     reg = &env->mstateen[csrno - CSR_MSTATEEN0];
     write_smstateen(env, reg, wr_mask, new_val);
@@ -1649,7 +1718,8 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
 {
     uint64_t *reg;
     uint64_t val;
-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
+                       (1UL << SMSTATEEN0_HSENVCFG);
 
     reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
     val = (uint64_t)new_val << 32;
@@ -1671,7 +1741,8 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
                                      target_ulong new_val)
 {
     uint64_t *reg;
-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
+                       (1UL << SMSTATEEN0_HSENVCFG);
     int index = csrno - CSR_HSTATEEN0;
 
     reg = &env->hstateen[index];
@@ -1694,8 +1765,9 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
 {
     uint64_t *reg;
     uint64_t val;
-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
     int index = csrno - CSR_HSTATEEN0H;
+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
+                       (1UL << SMSTATEEN0_HSENVCFG);
 
     reg = &env->hstateen[index];
     val = (uint64_t)new_val << 32;
-- 
2.25.1

Re: [RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[Alistair Francis]

On Sat, Jun 4, 2022 at 2:16 AM Mayuresh Chitale
<mchitale@ventanamicro.com> wrote:
>
> Accesses to henvcfg, henvcfgh and senvcfg are allowed
> only if corresponding bit in mstateen0/hstateen0 is
> enabled. Otherwise an illegal instruction trap is
> generated.
>
> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> ---
>  target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 78 insertions(+), 6 deletions(-)
>
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 324fefce59..ae91ae1f7e 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
>  }
>
>  /* Predicates */
> +static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
> +{
> +    CPUState *cs = env_cpu(env);
> +    RISCVCPU *cpu = RISCV_CPU(cs);
> +    bool virt = riscv_cpu_virt_enabled(env);
> +
> +    if (!cpu->cfg.ext_smstateen) {
> +        return RISCV_EXCP_NONE;
> +    }
> +
> +#if !defined(CONFIG_USER_ONLY)
> +    if (!(env->mstateen[0] & 1UL << bit)) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +
> +    if (virt) {
> +        if (!(env->hstateen[0] & 1UL << bit)) {
> +            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
> +        }
> +    }
> +
> +    if (mode == PRV_U) {
> +        if (!(env->sstateen[0] & 1UL << bit)) {
> +            return RISCV_EXCP_ILLEGAL_INST;
> +        }
> +    }
> +#endif
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
>  static RISCVException fs(CPURISCVState *env, int csrno)
>  {
>  #if !defined(CONFIG_USER_ONLY)
> @@ -1557,6 +1588,13 @@ static RISCVException write_menvcfgh(CPURISCVState *env, int csrno,
>  static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);

Couldn't this be part of the original permission check so we don't
need a second check?

Alistair

> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->senvcfg;
>      return RISCV_EXCP_NONE;
>  }
> @@ -1565,15 +1603,27 @@ static RISCVException write_senvcfg(CPURISCVState *env, int csrno,
>                                    target_ulong val)
>  {
>      uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE | SENVCFG_CBZE;
> +    RISCVException ret;
>
> -    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
> +    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
>      return RISCV_EXCP_NONE;
>  }
>
>  static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->henvcfg;
>      return RISCV_EXCP_NONE;
>  }
> @@ -1582,6 +1632,12 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
>                                    target_ulong val)
>  {
>      uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE | HENVCFG_CBZE;
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
>      if (riscv_cpu_mxl(env) == MXL_RV64) {
>          mask |= HENVCFG_PBMTE | HENVCFG_STCE;
> @@ -1595,6 +1651,13 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
>  static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->henvcfg >> 32;
>      return RISCV_EXCP_NONE;
>  }
> @@ -1604,9 +1667,14 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
>  {
>      uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
>      uint64_t valh = (uint64_t)val << 32;
> +    RISCVException ret;
>
> -    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
> +    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
>      return RISCV_EXCP_NONE;
>  }
>
> @@ -1628,7 +1696,8 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>                                       target_ulong new_val)
>  {
>      uint64_t *reg;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>      write_smstateen(env, reg, wr_mask, new_val);
> @@ -1649,7 +1718,8 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
>  {
>      uint64_t *reg;
>      uint64_t val;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>      val = (uint64_t)new_val << 32;
> @@ -1671,7 +1741,8 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>                                       target_ulong new_val)
>  {
>      uint64_t *reg;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>      int index = csrno - CSR_HSTATEEN0;
>
>      reg = &env->hstateen[index];
> @@ -1694,8 +1765,9 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
>  {
>      uint64_t *reg;
>      uint64_t val;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>      int index = csrno - CSR_HSTATEEN0H;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->hstateen[index];
>      val = (uint64_t)new_val << 32;
> --
> 2.25.1
>
>

Re: [RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[Alistair Francis]

On Thu, Jun 16, 2022 at 4:54 PM Alistair Francis <alistair23@gmail.com> wrote:
>
> On Sat, Jun 4, 2022 at 2:16 AM Mayuresh Chitale
> <mchitale@ventanamicro.com> wrote:
> >
> > Accesses to henvcfg, henvcfgh and senvcfg are allowed
> > only if corresponding bit in mstateen0/hstateen0 is
> > enabled. Otherwise an illegal instruction trap is
> > generated.
> >
> > Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> > ---
> >  target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++----
> >  1 file changed, 78 insertions(+), 6 deletions(-)
> >
> > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > index 324fefce59..ae91ae1f7e 100644
> > --- a/target/riscv/csr.c
> > +++ b/target/riscv/csr.c
> > @@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
> >  }
> >
> >  /* Predicates */
> > +static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
> > +{
> > +    CPUState *cs = env_cpu(env);
> > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > +    bool virt = riscv_cpu_virt_enabled(env);
> > +
> > +    if (!cpu->cfg.ext_smstateen) {
> > +        return RISCV_EXCP_NONE;
> > +    }
> > +
> > +#if !defined(CONFIG_USER_ONLY)
> > +    if (!(env->mstateen[0] & 1UL << bit)) {
> > +        return RISCV_EXCP_ILLEGAL_INST;
> > +    }
> > +
> > +    if (virt) {
> > +        if (!(env->hstateen[0] & 1UL << bit)) {
> > +            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
> > +        }
> > +    }
> > +
> > +    if (mode == PRV_U) {
> > +        if (!(env->sstateen[0] & 1UL << bit)) {
> > +            return RISCV_EXCP_ILLEGAL_INST;
> > +        }
> > +    }
> > +#endif
> > +
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> >  static RISCVException fs(CPURISCVState *env, int csrno)
> >  {
> >  #if !defined(CONFIG_USER_ONLY)
> > @@ -1557,6 +1588,13 @@ static RISCVException write_menvcfgh(CPURISCVState *env, int csrno,
> >  static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
> >                                   target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>
> Couldn't this be part of the original permission check so we don't
> need a second check?

Whoops, misread the function. Ignore that

Alistair

>
> Alistair
>
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      *val = env->senvcfg;
> >      return RISCV_EXCP_NONE;
> >  }
> > @@ -1565,15 +1603,27 @@ static RISCVException write_senvcfg(CPURISCVState *env, int csrno,
> >                                    target_ulong val)
> >  {
> >      uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE | SENVCFG_CBZE;
> > +    RISCVException ret;
> >
> > -    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> >
> > +    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
> >      return RISCV_EXCP_NONE;
> >  }
> >
> >  static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
> >                                   target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      *val = env->henvcfg;
> >      return RISCV_EXCP_NONE;
> >  }
> > @@ -1582,6 +1632,12 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
> >                                    target_ulong val)
> >  {
> >      uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE | HENVCFG_CBZE;
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> >
> >      if (riscv_cpu_mxl(env) == MXL_RV64) {
> >          mask |= HENVCFG_PBMTE | HENVCFG_STCE;
> > @@ -1595,6 +1651,13 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
> >  static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
> >                                   target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      *val = env->henvcfg >> 32;
> >      return RISCV_EXCP_NONE;
> >  }
> > @@ -1604,9 +1667,14 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
> >  {
> >      uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
> >      uint64_t valh = (uint64_t)val << 32;
> > +    RISCVException ret;
> >
> > -    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> >
> > +    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
> >      return RISCV_EXCP_NONE;
> >  }
> >
> > @@ -1628,7 +1696,8 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
> >                                       target_ulong new_val)
> >  {
> >      uint64_t *reg;
> > -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> > +                       (1UL << SMSTATEEN0_HSENVCFG);
> >
> >      reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> >      write_smstateen(env, reg, wr_mask, new_val);
> > @@ -1649,7 +1718,8 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
> >  {
> >      uint64_t *reg;
> >      uint64_t val;
> > -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> > +                       (1UL << SMSTATEEN0_HSENVCFG);
> >
> >      reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> >      val = (uint64_t)new_val << 32;
> > @@ -1671,7 +1741,8 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
> >                                       target_ulong new_val)
> >  {
> >      uint64_t *reg;
> > -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> > +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> > +                       (1UL << SMSTATEEN0_HSENVCFG);
> >      int index = csrno - CSR_HSTATEEN0;
> >
> >      reg = &env->hstateen[index];
> > @@ -1694,8 +1765,9 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
> >  {
> >      uint64_t *reg;
> >      uint64_t val;
> > -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >      int index = csrno - CSR_HSTATEEN0H;
> > +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> > +                       (1UL << SMSTATEEN0_HSENVCFG);
> >
> >      reg = &env->hstateen[index];
> >      val = (uint64_t)new_val << 32;
> > --
> > 2.25.1
> >
> >

Re: [RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[Alistair Francis]

On Sat, Jun 4, 2022 at 2:16 AM Mayuresh Chitale
<mchitale@ventanamicro.com> wrote:
>
> Accesses to henvcfg, henvcfgh and senvcfg are allowed
> only if corresponding bit in mstateen0/hstateen0 is
> enabled. Otherwise an illegal instruction trap is
> generated.
>
> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 78 insertions(+), 6 deletions(-)
>
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 324fefce59..ae91ae1f7e 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
>  }
>
>  /* Predicates */
> +static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
> +{
> +    CPUState *cs = env_cpu(env);
> +    RISCVCPU *cpu = RISCV_CPU(cs);
> +    bool virt = riscv_cpu_virt_enabled(env);
> +
> +    if (!cpu->cfg.ext_smstateen) {
> +        return RISCV_EXCP_NONE;
> +    }
> +
> +#if !defined(CONFIG_USER_ONLY)
> +    if (!(env->mstateen[0] & 1UL << bit)) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +
> +    if (virt) {
> +        if (!(env->hstateen[0] & 1UL << bit)) {
> +            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
> +        }
> +    }
> +
> +    if (mode == PRV_U) {
> +        if (!(env->sstateen[0] & 1UL << bit)) {
> +            return RISCV_EXCP_ILLEGAL_INST;
> +        }
> +    }
> +#endif
> +
> +    return RISCV_EXCP_NONE;
> +}
> +
>  static RISCVException fs(CPURISCVState *env, int csrno)
>  {
>  #if !defined(CONFIG_USER_ONLY)
> @@ -1557,6 +1588,13 @@ static RISCVException write_menvcfgh(CPURISCVState *env, int csrno,
>  static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->senvcfg;
>      return RISCV_EXCP_NONE;
>  }
> @@ -1565,15 +1603,27 @@ static RISCVException write_senvcfg(CPURISCVState *env, int csrno,
>                                    target_ulong val)
>  {
>      uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE | SENVCFG_CBZE;
> +    RISCVException ret;
>
> -    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
> +    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
>      return RISCV_EXCP_NONE;
>  }
>
>  static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->henvcfg;
>      return RISCV_EXCP_NONE;
>  }
> @@ -1582,6 +1632,12 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
>                                    target_ulong val)
>  {
>      uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE | HENVCFG_CBZE;
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
>      if (riscv_cpu_mxl(env) == MXL_RV64) {
>          mask |= HENVCFG_PBMTE | HENVCFG_STCE;
> @@ -1595,6 +1651,13 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
>  static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->henvcfg >> 32;
>      return RISCV_EXCP_NONE;
>  }
> @@ -1604,9 +1667,14 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
>  {
>      uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
>      uint64_t valh = (uint64_t)val << 32;
> +    RISCVException ret;
>
> -    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
> +    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
>      return RISCV_EXCP_NONE;
>  }
>
> @@ -1628,7 +1696,8 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>                                       target_ulong new_val)
>  {
>      uint64_t *reg;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>      write_smstateen(env, reg, wr_mask, new_val);
> @@ -1649,7 +1718,8 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
>  {
>      uint64_t *reg;
>      uint64_t val;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>      val = (uint64_t)new_val << 32;
> @@ -1671,7 +1741,8 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>                                       target_ulong new_val)
>  {
>      uint64_t *reg;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>      int index = csrno - CSR_HSTATEEN0;
>
>      reg = &env->hstateen[index];
> @@ -1694,8 +1765,9 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
>  {
>      uint64_t *reg;
>      uint64_t val;
> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>      int index = csrno - CSR_HSTATEEN0H;
> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> +                       (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->hstateen[index];
>      val = (uint64_t)new_val << 32;
> --
> 2.25.1
>
>

Re:[RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[angell1518]

[-- Attachment #1: Type: text/plain, Size: 6608 bytes --]

At 2022-06-04 00:04:23, "Mayuresh Chitale" <mchitale@ventanamicro.com> wrote:

>Accesses to henvcfg, henvcfgh and senvcfg are allowed
>only if corresponding bit in mstateen0/hstateen0 is
>enabled. Otherwise an illegal instruction trap is
>generated.
>
>Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
>---
> target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 78 insertions(+), 6 deletions(-)
>
>diff --git a/target/riscv/csr.c b/target/riscv/csr.c
>index 324fefce59..ae91ae1f7e 100644
>--- a/target/riscv/csr.c
>+++ b/target/riscv/csr.ccounteren
>@@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
> }
> 
> /* Predicates */
>+static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
>+{
>+    CPUState *cs = env_cpu(env);
>+    RISCVCPU *cpu = RISCV_CPU(cs);
>+    bool virt = riscv_cpu_virt_enabled(env);
>+
>+    if (!cpu->cfg.ext_smstateen) {
>+        return RISCV_EXCP_NONE;
>+    }
>+
>+#if !defined(CONFIG_USER_ONLY)
>+    if (!(env->mstateen[0] & 1UL << bit)) {
>+        return RISCV_EXCP_ILLEGAL_INST;
>+    }
>+
I think mstateen only control access in priv mode under M mode. 

So we should take the current priv node into consideration here.

>+    if (virt) {
>+        if (!(env->hstateen[0] & 1UL << bit)) {
>+            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
>+        }
>+    }
>+
>+    if (mode == PRV_U) {
>+        if (!(env->sstateen[0] & 1UL << bit)) {
>+            return RISCV_EXCP_ILLEGAL_INST;

>+ }
I think there are two problem here:

The first is that we should also take virt mode into consideration here too. As the spec said:

"if executing in VS or VU mode and the circumstances for a virtual instruction
exception apply, raises a virtual instruction exception instead of an illegal instruction exception"

So it will generate RISCV_EXCP_VIRT_INSTRUCTION_FAULT in VU mode.


The second is that sstateen csr works only when 'S' extension is enabled



Regards,
Weiwei Li

>+    }
>+#endif
>+
>+    return RISCV_EXCP_NONE;
>+}
>+
> static RISCVException fs(CPURISCVState *env, int csrno)
> {
> #if !defined(CONFIG_USER_ONLY)
>@@ -1557,6 +1588,13 @@ static RISCVException write_menvcfgh(CPURISCVState *env, int csrno,
> static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
>                                  target_ulong *val)
> {
>+    RISCVException ret;
>+
>+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>+    if (ret != RISCV_EXCP_NONE) {
>+        return ret;
>+    }
>+
>     *val = env->senvcfg;
>     return RISCV_EXCP_NONE;
> }
>@@ -1565,15 +1603,27 @@ static RISCVException write_senvcfg(CPURISCVState *env, int csrno,
>                                   target_ulong val)
> {
>     uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE | SENVCFG_CBZE;
>+    RISCVException ret;
> 
>-    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
>+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>+    if (ret != RISCV_EXCP_NONE) {
>+        return ret;
>+    }
> 
>+    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
>     return RISCV_EXCP_NONE;
> }
> 
> static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
>                                  target_ulong *val)
> {
>+    RISCVException ret;
>+
>+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>+    if (ret != RISCV_EXCP_NONE) {
>+        return ret;
>+    }
>+
>     *val = env->henvcfg;
>     return RISCV_EXCP_NONE;
> }
>@@ -1582,6 +1632,12 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
>                                   target_ulong val)
> {
>     uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE | HENVCFG_CBZE;
>+    RISCVException ret;
>+
>+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>+    if (ret != RISCV_EXCP_NONE) {
>+        return ret;
>+    }
> 
>     if (riscv_cpu_mxl(env) == MXL_RV64) {
>         mask |= HENVCFG_PBMTE | HENVCFG_STCE;
>@@ -1595,6 +1651,13 @@ static RISCVException write_henvcfg(CPURISCVState *env, int csrno,
> static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
>                                  target_ulong *val)
> {
>+    RISCVException ret;
>+
>+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>+    if (ret != RISCV_EXCP_NONE) {
>+        return ret;
>+    }
>+
>     *val = env->henvcfg >> 32;
>     return RISCV_EXCP_NONE;
> }
>@@ -1604,9 +1667,14 @@ static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
> {
>     uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
>     uint64_t valh = (uint64_t)val << 32;
>+    RISCVException ret;
> 
>-    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
>+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>+    if (ret != RISCV_EXCP_NONE) {
>+        return ret;
>+    }
> 
>+    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
>     return RISCV_EXCP_NONE;
> }
> 
>@@ -1628,7 +1696,8 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>                                      target_ulong new_val)
> {
>     uint64_t *reg;
>-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>+                       (1UL << SMSTATEEN0_HSENVCFG);
> 
>     reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>     write_smstateen(env, reg, wr_mask, new_val);
>@@ -1649,7 +1718,8 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
> {
>     uint64_t *reg;
>     uint64_t val;
>-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>+                       (1UL << SMSTATEEN0_HSENVCFG);
> 
>     reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>     val = (uint64_t)new_val << 32;
>@@ -1671,7 +1741,8 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>                                      target_ulong new_val)
> {
>     uint64_t *reg;
>-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>+                       (1UL << SMSTATEEN0_HSENVCFG);
>     int index = csrno - CSR_HSTATEEN0;
> 
>     reg = &env->hstateen[index];
>@@ -1694,8 +1765,9 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
> {
>     uint64_t *reg;
>     uint64_t val;
>-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>     int index = csrno - CSR_HSTATEEN0H;
>+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>+                       (1UL << SMSTATEEN0_HSENVCFG);
> 
>     reg = &env->hstateen[index];
>     val = (uint64_t)new_val << 32;
>-- 
>2.25.1
>

[-- Attachment #2: Type: text/html, Size: 7711 bytes --]

Re: [RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[Mayuresh Chitale]

On Sat, 2022-07-02 at 18:33 +0800, angell1518 wrote:
> At 2022-06-04 00:04:23, "Mayuresh Chitale" <mchitale@ventanamicro.com
> > wrote:
> >Accesses to henvcfg, henvcfgh and senvcfg are allowed
> >only if corresponding bit in mstateen0/hstateen0 is
> >enabled. Otherwise an illegal instruction trap is
> >generated.
> >
> >Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> >---
> > target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++-
> ---
> > 1 file changed, 78 insertions(+), 6 deletions(-)
> >
> >diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> >index 324fefce59..ae91ae1f7e 100644
> >--- a/target/riscv/csr.c
> >+++ b/target/riscv/csr.ccounteren
> >@@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno,
> riscv_csr_operations *ops)
> > }
> > 
> > /* Predicates */
> >+static RISCVException smstateen_acc_ok(CPURISCVState *env, int
> mode, int bit)
> >+{
> >+    CPUState *cs = env_cpu(env);
> >+    RISCVCPU *cpu = RISCV_CPU(cs);
> >+    bool virt = riscv_cpu_virt_enabled(env);
> >+
> >+    if (!cpu->cfg.ext_smstateen) {
> >+        return RISCV_EXCP_NONE;
> >+    }
> >+
> >+#if !defined(CONFIG_USER_ONLY)
> >+    if (!(env->mstateen[0] & 1UL << bit)) {
> >+        return RISCV_EXCP_ILLEGAL_INST;
> >+    }
> >+
> I think mstateen only control access in priv mode under M mode.  
> So we should take the current priv node into consideration here.

For any curent priv mode if the required bit is not set in mstateen we
can return here itself. For e.g if current priv mode is S then we only
check the required bit in mstateen. If current priv mode is 'U', we
need to check the required bit in mstateen and sstateen

> >+    if (virt) {
> >+        if (!(env->hstateen[0] & 1UL << bit)) {
> >+            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
> >+        }
> >+    }
> >+
> >+    if (mode == PRV_U) {
> >+        if (!(env->sstateen[0] & 1UL << bit)) {
> >+            return RISCV_EXCP_ILLEGAL_INST;
> >+ }
> I think there are two problem here:
> The first is that we should also take virt mode into consideration
> here too. 
Actually virt mode is considered above for both priv modes S and U.
> As the spec said: 
> "if executing in VS or VU mode and the circumstances for a virtual
> instruction
> exception apply, raises a virtual instruction exception instead of an
> illegal instruction exception"
> So it will generate RISCV_EXCP_VIRT_INSTRUCTION_FAULT in VU mode.

> 
> The second is that sstateen csr works only when 'S' extension is
> enabled
> 
I will fix it in the next version.

> Regards,
> Weiwei Li
> >+    }
> >+#endif
> >+
> >+    return RISCV_EXCP_NONE;
> >+}
> >+
> > static RISCVException fs(CPURISCVState *env, int csrno)
> > {
> > #if !defined(CONFIG_USER_ONLY)
> >@@ -1557,6 +1588,13 @@ static RISCVException
> write_menvcfgh(CPURISCVState *env, int csrno,
> > static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
> >                                  target_ulong *val)
> > {
> >+    RISCVException ret;
> >+
> >+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> >+    if (ret != RISCV_EXCP_NONE) {
> >+        return ret;
> >+    }
> >+
> >     *val = env->senvcfg;
> >     return RISCV_EXCP_NONE;
> > }
> >@@ -1565,15 +1603,27 @@ static RISCVException
> write_senvcfg(CPURISCVState *env, int csrno,
> >                                   target_ulong val)
> > {
> >     uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE |
> SENVCFG_CBZE;
> >+    RISCVException ret;
> > 
> >-    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
> >+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> >+    if (ret != RISCV_EXCP_NONE) {
> >+        return ret;
> >+    }
> > 
> >+    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
> >     return RISCV_EXCP_NONE;
> > }
> > 
> > static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
> >                                  target_ulong *val)
> > {
> >+    RISCVException ret;
> >+
> >+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> >+    if (ret != RISCV_EXCP_NONE) {
> >+        return ret;
> >+    }
> >+
> >     *val = env->henvcfg;
> >     return RISCV_EXCP_NONE;
> > }
> >@@ -1582,6 +1632,12 @@ static RISCVException
> write_henvcfg(CPURISCVState *env, int csrno,
> >                                   target_ulong val)
> > {
> >     uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE |
> HENVCFG_CBZE;
> >+    RISCVException ret;
> >+
> >+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> >+    if (ret != RISCV_EXCP_NONE) {
> >+        return ret;
> >+    }
> > 
> >     if (riscv_cpu_mxl(env) == MXL_RV64) {
> >         mask |= HENVCFG_PBMTE | HENVCFG_STCE;
> >@@ -1595,6 +1651,13 @@ static RISCVException
> write_henvcfg(CPURISCVState *env, int csrno,
> > static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
> >                                  target_ulong *val)
> > {
> >+    RISCVException ret;
> >+
> >+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> >+    if (ret != RISCV_EXCP_NONE) {
> >+        return ret;
> >+    }
> >+
> >     *val = env->henvcfg >> 32;
> >     return RISCV_EXCP_NONE;
> > }
> >@@ -1604,9 +1667,14 @@ static RISCVException
> write_henvcfgh(CPURISCVState *env, int csrno,
> > {
> >     uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
> >     uint64_t valh = (uint64_t)val << 32;
> >+    RISCVException ret;
> > 
> >-    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
> >+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
> >+    if (ret != RISCV_EXCP_NONE) {
> >+        return ret;
> >+    }
> > 
> >+    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
> >     return RISCV_EXCP_NONE;
> > }
> > 
> >@@ -1628,7 +1696,8 @@ static RISCVException
> write_mstateen(CPURISCVState *env, int csrno,
> >                                      target_ulong new_val)
> > {
> >     uint64_t *reg;
> >-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> >+                       (1UL << SMSTATEEN0_HSENVCFG);
> > 
> >     reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> >     write_smstateen(env, reg, wr_mask, new_val);
> >@@ -1649,7 +1718,8 @@ static RISCVException
> write_mstateenh(CPURISCVState *env, int csrno,
> > {
> >     uint64_t *reg;
> >     uint64_t val;
> >-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> >+                       (1UL << SMSTATEEN0_HSENVCFG);
> > 
> >     reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> >     val = (uint64_t)new_val << 32;
> >@@ -1671,7 +1741,8 @@ static RISCVException
> write_hstateen(CPURISCVState *env, int csrno,
> >                                      target_ulong new_val)
> > {
> >     uint64_t *reg;
> >-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> >+                       (1UL << SMSTATEEN0_HSENVCFG);
> >     int index = csrno - CSR_HSTATEEN0;
> > 
> >     reg = &env->hstateen[index];
> >@@ -1694,8 +1765,9 @@ static RISCVException
> write_hstateenh(CPURISCVState *env, int csrno,
> > {
> >     uint64_t *reg;
> >     uint64_t val;
> >-    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
> >     int index = csrno - CSR_HSTATEEN0H;
> >+    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> >+                       (1UL << SMSTATEEN0_HSENVCFG);
> > 
> >     reg = &env->hstateen[index];
> >     val = (uint64_t)new_val << 32;
> >-- 
> >2.25.1
> >

Re: [RFC PATCH v5 2/4] target/riscv: smstateen check for h/senvcfg

[Weiwei Li]

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在 2022/7/8 上午1:20, Mayuresh Chitale 写道:
> On Sat, 2022-07-02 at 18:33 +0800, angell1518 wrote:
>> At 2022-06-04 00:04:23, "Mayuresh Chitale" <mchitale@ventanamicro.com
>>> wrote:
>>> Accesses to henvcfg, henvcfgh and senvcfg are allowed
>>> only if corresponding bit in mstateen0/hstateen0 is
>>> enabled. Otherwise an illegal instruction trap is
>>> generated.
>>>
>>> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
>>> ---
>>> target/riscv/csr.c | 84 ++++++++++++++++++++++++++++++++++++++++++-
>> ---
>>> 1 file changed, 78 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
>>> index 324fefce59..ae91ae1f7e 100644
>>> --- a/target/riscv/csr.c
>>> +++ b/target/riscv/csr.ccounteren
>>> @@ -39,6 +39,37 @@ void riscv_set_csr_ops(int csrno,
>> riscv_csr_operations *ops)
>>> }
>>>
>>> /* Predicates */
>>> +static RISCVException smstateen_acc_ok(CPURISCVState *env, int
>> mode, int bit)
>>> +{
>>> +    CPUState *cs = env_cpu(env);
>>> +    RISCVCPU *cpu = RISCV_CPU(cs);
>>> +    bool virt = riscv_cpu_virt_enabled(env);
>>> +
>>> +    if (!cpu->cfg.ext_smstateen) {
>>> +        return RISCV_EXCP_NONE;
>>> +    }
>>> +
>>> +#if !defined(CONFIG_USER_ONLY)
>>> +    if (!(env->mstateen[0] & 1UL << bit)) {
>>> +        return RISCV_EXCP_ILLEGAL_INST;
>>> +    }
>>> +
>> I think mstateen only control access in priv mode under M mode.
>> So we should take the current priv node into consideration here.
> For any curent priv mode if the required bit is not set in mstateen we
> can return here itself. For e.g if current priv mode is S then we only
> check the required bit in mstateen. If current priv mode is 'U', we
> need to check the required bit in mstateen and sstateen
>
mstateen only controls the access from less-privilege mode. So do hstateen and sstateen.  we should pass all of the
check, if current priv is PRV_M. like this:
+    if (env->priv == PRV_M) {
+        return RISCV_EXCP_NONE;
+    }

>>> +    if (virt) {
>>> +        if (!(env->hstateen[0] & 1UL << bit)) {
>>> +            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
>>> +        }
>>> +    }
>>> +
>>> +    if (mode == PRV_U) {
>>> +        if (!(env->sstateen[0] & 1UL << bit)) {
>>> +            return RISCV_EXCP_ILLEGAL_INST;
>>> + }
>> I think there are two problem here:
>> The first is that we should also take virt mode into consideration
>> here too.
> Actually virt mode is considered above for both priv modes S and U.

Yeah(we also should pass this check for current priv is PRV_M). However, 
there's still a problem

here: the mode here is the mode for csr not the current priv mode.  
Actually, Sstateen will control the access

for user mode csr(such as fcsr)  from U mode. So taking the following 
question into consideration, the  total check

may be:

+    if (mode == PRV_U &&env->priv == PRV_U) {
+        if (riscv_has_ext(env, RVS)  && !(env->sstateen[0] & 1UL << bit)) {
+            return RISCV_EXCP_ILLEGAL_INST;
+ }

Regards,
Weiwei Li

>> As the spec said:
>> "if executing in VS or VU mode and the circumstances for a virtual
>> instruction
>> exception apply, raises a virtual instruction exception instead of an
>> illegal instruction exception"
>> So it will generate RISCV_EXCP_VIRT_INSTRUCTION_FAULT in VU mode.
>> The second is that sstateen csr works only when 'S' extension is
>> enabled
>>
> I will fix it in the next version.
>
>> Regards,
>> Weiwei Li
>>> +    }
>>> +#endif
>>> +
>>> +    return RISCV_EXCP_NONE;
>>> +}
>>> +
>>> static RISCVException fs(CPURISCVState *env, int csrno)
>>> {
>>> #if !defined(CONFIG_USER_ONLY)
>>> @@ -1557,6 +1588,13 @@ static RISCVException
>> write_menvcfgh(CPURISCVState *env, int csrno,
>>> static RISCVException read_senvcfg(CPURISCVState *env, int csrno,
>>>                                   target_ulong *val)
>>> {
>>> +    RISCVException ret;
>>> +
>>> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>>> +    if (ret != RISCV_EXCP_NONE) {
>>> +        return ret;
>>> +    }
>>> +
>>>      *val = env->senvcfg;
>>>      return RISCV_EXCP_NONE;
>>> }
>>> @@ -1565,15 +1603,27 @@ static RISCVException
>> write_senvcfg(CPURISCVState *env, int csrno,
>>>                                    target_ulong val)
>>> {
>>>      uint64_t mask = SENVCFG_FIOM | SENVCFG_CBIE | SENVCFG_CBCFE |
>> SENVCFG_CBZE;
>>> +    RISCVException ret;
>>>
>>> -    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
>>> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>>> +    if (ret != RISCV_EXCP_NONE) {
>>> +        return ret;
>>> +    }
>>>
>>> +    env->senvcfg = (env->senvcfg & ~mask) | (val & mask);
>>>      return RISCV_EXCP_NONE;
>>> }
>>>
>>> static RISCVException read_henvcfg(CPURISCVState *env, int csrno,
>>>                                   target_ulong *val)
>>> {
>>> +    RISCVException ret;
>>> +
>>> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>>> +    if (ret != RISCV_EXCP_NONE) {
>>> +        return ret;
>>> +    }
>>> +
>>>      *val = env->henvcfg;
>>>      return RISCV_EXCP_NONE;
>>> }
>>> @@ -1582,6 +1632,12 @@ static RISCVException
>> write_henvcfg(CPURISCVState *env, int csrno,
>>>                                    target_ulong val)
>>> {
>>>      uint64_t mask = HENVCFG_FIOM | HENVCFG_CBIE | HENVCFG_CBCFE |
>> HENVCFG_CBZE;
>>> +    RISCVException ret;
>>> +
>>> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>>> +    if (ret != RISCV_EXCP_NONE) {
>>> +        return ret;
>>> +    }
>>>
>>>      if (riscv_cpu_mxl(env) == MXL_RV64) {
>>>          mask |= HENVCFG_PBMTE | HENVCFG_STCE;
>>> @@ -1595,6 +1651,13 @@ static RISCVException
>> write_henvcfg(CPURISCVState *env, int csrno,
>>> static RISCVException read_henvcfgh(CPURISCVState *env, int csrno,
>>>                                   target_ulong *val)
>>> {
>>> +    RISCVException ret;
>>> +
>>> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>>> +    if (ret != RISCV_EXCP_NONE) {
>>> +        return ret;
>>> +    }
>>> +
>>>      *val = env->henvcfg >> 32;
>>>      return RISCV_EXCP_NONE;
>>> }
>>> @@ -1604,9 +1667,14 @@ static RISCVException
>> write_henvcfgh(CPURISCVState *env, int csrno,
>>> {
>>>      uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
>>>      uint64_t valh = (uint64_t)val << 32;
>>> +    RISCVException ret;
>>>
>>> -    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
>>> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_HSENVCFG);
>>> +    if (ret != RISCV_EXCP_NONE) {
>>> +        return ret;
>>> +    }
>>>
>>> +    env->henvcfg = (env->henvcfg & ~mask) | (valh & mask);
>>>      return RISCV_EXCP_NONE;
>>> }
>>>
>>> @@ -1628,7 +1696,8 @@ static RISCVException
>> write_mstateen(CPURISCVState *env, int csrno,
>>>                                       target_ulong new_val)
>>> {
>>>      uint64_t *reg;
>>> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>>> +                       (1UL << SMSTATEEN0_HSENVCFG);
>>>
>>>      reg = &env->mstateen[csrno - CSR_MSTATEEN0];
>>>      write_smstateen(env, reg, wr_mask, new_val);
>>> @@ -1649,7 +1718,8 @@ static RISCVException
>> write_mstateenh(CPURISCVState *env, int csrno,
>>> {
>>>      uint64_t *reg;
>>>      uint64_t val;
>>> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>>> +                       (1UL << SMSTATEEN0_HSENVCFG);
>>>
>>>      reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>>>      val = (uint64_t)new_val << 32;
>>> @@ -1671,7 +1741,8 @@ static RISCVException
>> write_hstateen(CPURISCVState *env, int csrno,
>>>                                       target_ulong new_val)
>>> {
>>>      uint64_t *reg;
>>> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>>> +                       (1UL << SMSTATEEN0_HSENVCFG);
>>>      int index = csrno - CSR_HSTATEEN0;
>>>
>>>      reg = &env->hstateen[index];
>>> @@ -1694,8 +1765,9 @@ static RISCVException
>> write_hstateenh(CPURISCVState *env, int csrno,
>>> {
>>>      uint64_t *reg;
>>>      uint64_t val;
>>> -    uint64_t wr_mask = 1UL << SMSTATEEN_STATEN;
>>>      int index = csrno - CSR_HSTATEEN0H;
>>> +    uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>>> +                       (1UL << SMSTATEEN0_HSENVCFG);
>>>
>>>      reg = &env->hstateen[index];
>>>      val = (uint64_t)new_val << 32;
>>> -- 
>>> 2.25.1
>>>

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[RFC PATCH v5 3/4] target/riscv: smstateen check for fcsr

[Mayuresh Chitale]

If smstateen is implemented and sstateen0.fcsr is clear
then the floating point operations must return illegal
instruction exception.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
---
 target/riscv/csr.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index ae91ae1f7e..8bbbed38ff 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -77,6 +77,10 @@ static RISCVException fs(CPURISCVState *env, int csrno)
         !RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
         return RISCV_EXCP_ILLEGAL_INST;
     }
+
+    if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
+        return smstateen_acc_ok(env, PRV_U, SMSTATEEN0_FCSR);
+    }
 #endif
     return RISCV_EXCP_NONE;
 }
@@ -1700,6 +1704,10 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
                        (1UL << SMSTATEEN0_HSENVCFG);
 
     reg = &env->mstateen[csrno - CSR_MSTATEEN0];
+    if (riscv_has_ext(env, RVF)) {
+        wr_mask |= 1UL << SMSTATEEN0_FCSR;
+    }
+
     write_smstateen(env, reg, wr_mask, new_val);
 
     return RISCV_EXCP_NONE;
@@ -1724,6 +1732,10 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
     reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
     val = (uint64_t)new_val << 32;
     val |= *reg & 0xFFFFFFFF;
+    if (riscv_has_ext(env, RVF)) {
+        wr_mask |= 1UL << SMSTATEEN0_FCSR;
+    }
+
     write_smstateen(env, reg, wr_mask, val);
 
     return RISCV_EXCP_NONE;
@@ -1745,6 +1757,10 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
                        (1UL << SMSTATEEN0_HSENVCFG);
     int index = csrno - CSR_HSTATEEN0;
 
+    if (riscv_has_ext(env, RVF)) {
+        wr_mask |= 1UL << SMSTATEEN0_FCSR;
+    }
+
     reg = &env->hstateen[index];
     wr_mask &= env->mstateen[index];
     write_smstateen(env, reg, wr_mask, new_val);
@@ -1769,6 +1785,10 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
     uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
                        (1UL << SMSTATEEN0_HSENVCFG);
 
+    if (riscv_has_ext(env, RVF)) {
+        wr_mask |= 1UL << SMSTATEEN0_FCSR;
+    }
+
     reg = &env->hstateen[index];
     val = (uint64_t)new_val << 32;
     val |= *reg & 0xFFFFFFFF;
@@ -1794,6 +1814,10 @@ static RISCVException write_sstateen(CPURISCVState *env, int csrno,
     int index = csrno - CSR_SSTATEEN0;
     bool virt = riscv_cpu_virt_enabled(env);
 
+    if (riscv_has_ext(env, RVF)) {
+        wr_mask |= 1UL << SMSTATEEN0_FCSR;
+    }
+
     reg = &env->sstateen[index];
     if (virt) {
         wr_mask &= env->mstateen[index];
-- 
2.25.1

Re: [RFC PATCH v5 3/4] target/riscv: smstateen check for fcsr

[Alistair Francis]

On Sat, Jun 4, 2022 at 2:08 AM Mayuresh Chitale
<mchitale@ventanamicro.com> wrote:
>
> If smstateen is implemented and sstateen0.fcsr is clear
> then the floating point operations must return illegal
> instruction exception.
>
> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> ---
>  target/riscv/csr.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
>
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index ae91ae1f7e..8bbbed38ff 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -77,6 +77,10 @@ static RISCVException fs(CPURISCVState *env, int csrno)
>          !RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
>          return RISCV_EXCP_ILLEGAL_INST;
>      }
> +
> +    if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
> +        return smstateen_acc_ok(env, PRV_U, SMSTATEEN0_FCSR);
> +    }

This only checks access to the CSRs. Shouldn't we also be throwing
errors if any instruction operates on an x register?

>  #endif
>      return RISCV_EXCP_NONE;
>  }
> @@ -1700,6 +1704,10 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>                         (1UL << SMSTATEEN0_HSENVCFG);
>
>      reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> +    if (riscv_has_ext(env, RVF)) {
> +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> +    }

This doesn't look right.

"Whenever misa.F = 1, bit 1 of mstateen0 is read-only zero". Shouldn't
that mean we don't allow writes if we have the RVF extension?

Alistair

> +
>      write_smstateen(env, reg, wr_mask, new_val);
>
>      return RISCV_EXCP_NONE;
> @@ -1724,6 +1732,10 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
>      reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
>      val = (uint64_t)new_val << 32;
>      val |= *reg & 0xFFFFFFFF;
> +    if (riscv_has_ext(env, RVF)) {
> +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> +    }
> +
>      write_smstateen(env, reg, wr_mask, val);
>
>      return RISCV_EXCP_NONE;
> @@ -1745,6 +1757,10 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>                         (1UL << SMSTATEEN0_HSENVCFG);
>      int index = csrno - CSR_HSTATEEN0;
>
> +    if (riscv_has_ext(env, RVF)) {
> +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> +    }
> +
>      reg = &env->hstateen[index];
>      wr_mask &= env->mstateen[index];
>      write_smstateen(env, reg, wr_mask, new_val);
> @@ -1769,6 +1785,10 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
>      uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
>                         (1UL << SMSTATEEN0_HSENVCFG);
>
> +    if (riscv_has_ext(env, RVF)) {
> +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> +    }
> +
>      reg = &env->hstateen[index];
>      val = (uint64_t)new_val << 32;
>      val |= *reg & 0xFFFFFFFF;
> @@ -1794,6 +1814,10 @@ static RISCVException write_sstateen(CPURISCVState *env, int csrno,
>      int index = csrno - CSR_SSTATEEN0;
>      bool virt = riscv_cpu_virt_enabled(env);
>
> +    if (riscv_has_ext(env, RVF)) {
> +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> +    }
> +
>      reg = &env->sstateen[index];
>      if (virt) {
>          wr_mask &= env->mstateen[index];
> --
> 2.25.1
>
>

Re: [RFC PATCH v5 3/4] target/riscv: smstateen check for fcsr

[Mayuresh Chitale]

On Thu, 2022-06-16 at 17:17 +1000, Alistair Francis wrote:
> On Sat, Jun 4, 2022 at 2:08 AM Mayuresh Chitale
> <mchitale@ventanamicro.com> wrote:
> > If smstateen is implemented and sstateen0.fcsr is clear
> > then the floating point operations must return illegal
> > instruction exception.
> > 
> > Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> > ---
> >  target/riscv/csr.c | 24 ++++++++++++++++++++++++
> >  1 file changed, 24 insertions(+)
> > 
> > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > index ae91ae1f7e..8bbbed38ff 100644
> > --- a/target/riscv/csr.c
> > +++ b/target/riscv/csr.c
> > @@ -77,6 +77,10 @@ static RISCVException fs(CPURISCVState *env, int
> > csrno)
> >          !RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
> >          return RISCV_EXCP_ILLEGAL_INST;
> >      }
> > +
> > +    if (!env->debugger && !riscv_cpu_fp_enabled(env)) {
> > +        return smstateen_acc_ok(env, PRV_U, SMSTATEEN0_FCSR);
> > +    }
> 
> This only checks access to the CSRs. Shouldn't we also be throwing
> errors if any instruction operates on an x register?
Yes.
> 
> >  #endif
> >      return RISCV_EXCP_NONE;
> >  }
> > @@ -1700,6 +1704,10 @@ static RISCVException
> > write_mstateen(CPURISCVState *env, int csrno,
> >                         (1UL << SMSTATEEN0_HSENVCFG);
> > 
> >      reg = &env->mstateen[csrno - CSR_MSTATEEN0];
> > +    if (riscv_has_ext(env, RVF)) {
> > +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> > +    }
> 
> This doesn't look right.
> 
> "Whenever misa.F = 1, bit 1 of mstateen0 is read-only zero".
> Shouldn't
> that mean we don't allow writes if we have the RVF extension?

I will fix it in the next version.
> 
> Alistair
> 
> > +
> >      write_smstateen(env, reg, wr_mask, new_val);
> > 
> >      return RISCV_EXCP_NONE;
> > @@ -1724,6 +1732,10 @@ static RISCVException
> > write_mstateenh(CPURISCVState *env, int csrno,
> >      reg = &env->mstateen[csrno - CSR_MSTATEEN0H];
> >      val = (uint64_t)new_val << 32;
> >      val |= *reg & 0xFFFFFFFF;
> > +    if (riscv_has_ext(env, RVF)) {
> > +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> > +    }
> > +
> >      write_smstateen(env, reg, wr_mask, val);
> > 
> >      return RISCV_EXCP_NONE;
> > @@ -1745,6 +1757,10 @@ static RISCVException
> > write_hstateen(CPURISCVState *env, int csrno,
> >                         (1UL << SMSTATEEN0_HSENVCFG);
> >      int index = csrno - CSR_HSTATEEN0;
> > 
> > +    if (riscv_has_ext(env, RVF)) {
> > +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> > +    }
> > +
> >      reg = &env->hstateen[index];
> >      wr_mask &= env->mstateen[index];
> >      write_smstateen(env, reg, wr_mask, new_val);
> > @@ -1769,6 +1785,10 @@ static RISCVException
> > write_hstateenh(CPURISCVState *env, int csrno,
> >      uint64_t wr_mask = (1UL << SMSTATEEN_STATEN) |
> >                         (1UL << SMSTATEEN0_HSENVCFG);
> > 
> > +    if (riscv_has_ext(env, RVF)) {
> > +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> > +    }
> > +
> >      reg = &env->hstateen[index];
> >      val = (uint64_t)new_val << 32;
> >      val |= *reg & 0xFFFFFFFF;
> > @@ -1794,6 +1814,10 @@ static RISCVException
> > write_sstateen(CPURISCVState *env, int csrno,
> >      int index = csrno - CSR_SSTATEEN0;
> >      bool virt = riscv_cpu_virt_enabled(env);
> > 
> > +    if (riscv_has_ext(env, RVF)) {
> > +        wr_mask |= 1UL << SMSTATEEN0_FCSR;
> > +    }
> > +
> >      reg = &env->sstateen[index];
> >      if (virt) {
> >          wr_mask &= env->mstateen[index];
> > --
> > 2.25.1
> > 
> > 

[RFC PATCH v5 4/4] target/riscv: smstateen check for AIA/IMSIC

[Mayuresh Chitale]

If smstateen is implemented then accesses to AIA
registers CSRS, IMSIC CSRs and other IMSIC registers
is controlled by setting of corresponding bits in
mstateen/hstateen registers. Otherwise an illegal
instruction trap or virtual instruction trap is
generated.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
---
 target/riscv/csr.c | 253 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 248 insertions(+), 5 deletions(-)

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 8bbbed38ff..213b3c17ff 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -39,6 +39,7 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
 }
 
 /* Predicates */
+#if !defined(CONFIG_USER_ONLY)
 static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
 {
     CPUState *cs = env_cpu(env);
@@ -49,7 +50,6 @@ static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
         return RISCV_EXCP_NONE;
     }
 
-#if !defined(CONFIG_USER_ONLY)
     if (!(env->mstateen[0] & 1UL << bit)) {
         return RISCV_EXCP_ILLEGAL_INST;
     }
@@ -65,11 +65,57 @@ static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
             return RISCV_EXCP_ILLEGAL_INST;
         }
     }
-#endif
-
     return RISCV_EXCP_NONE;
 }
 
+static RISCVException smstateen_aia_acc_ok(CPURISCVState *env, int csrno)
+{
+    int bit, mode;
+
+    switch (csrno) {
+    case CSR_SSETEIPNUM:
+    case CSR_SCLREIPNUM:
+    case CSR_SSETEIENUM:
+    case CSR_SCLREIENUM:
+    case CSR_STOPEI:
+    case CSR_VSSETEIPNUM:
+    case CSR_VSCLREIPNUM:
+    case CSR_VSSETEIENUM:
+    case CSR_VSCLREIENUM:
+    case CSR_VSTOPEI:
+    case CSR_HSTATUS:
+        mode = PRV_S;
+        bit = SMSTATEEN0_IMSIC;
+        break;
+
+    case CSR_SIEH:
+    case CSR_SIPH:
+    case CSR_HVIPH:
+    case CSR_HVICTL:
+    case CSR_HVIPRIO1:
+    case CSR_HVIPRIO2:
+    case CSR_HVIPRIO1H:
+    case CSR_HVIPRIO2H:
+    case CSR_VSIEH:
+    case CSR_VSIPH:
+        mode = PRV_S;
+        bit = SMSTATEEN0_AIA;
+        break;
+
+    case CSR_SISELECT:
+    case CSR_VSISELECT:
+        mode = PRV_S;
+        bit = SMSTATEEN0_SVSLCT;
+        break;
+
+    default:
+        return RISCV_EXCP_NONE;
+    }
+
+    return smstateen_acc_ok(env, mode, bit);
+}
+#endif
+
 static RISCVException fs(CPURISCVState *env, int csrno)
 {
 #if !defined(CONFIG_USER_ONLY)
@@ -1130,6 +1176,13 @@ static int rmw_xiselect(CPURISCVState *env, int csrno, target_ulong *val,
                         target_ulong new_val, target_ulong wr_mask)
 {
     target_ulong *iselect;
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
 
     /* Translate CSR number for VS-mode */
     csrno = aia_xlate_vs_csrno(env, csrno);
@@ -1212,7 +1265,9 @@ static int rmw_xireg(CPURISCVState *env, int csrno, target_ulong *val,
     bool virt;
     uint8_t *iprio;
     int ret = -EINVAL;
-    target_ulong priv, isel, vgein;
+    target_ulong priv, isel, vgein = 0;
+    CPUState *cs = env_cpu(env);
+    RISCVCPU *cpu = RISCV_CPU(cs);
 
     /* Translate CSR number for VS-mode */
     csrno = aia_xlate_vs_csrno(env, csrno);
@@ -1241,11 +1296,20 @@ static int rmw_xireg(CPURISCVState *env, int csrno, target_ulong *val,
     };
 
     /* Find the selected guest interrupt file */
-    vgein = (virt) ? get_field(env->hstatus, HSTATUS_VGEIN) : 0;
+    if (virt) {
+        if (!cpu->cfg.ext_smstateen ||
+                (env->hstateen[0] & 1UL << SMSTATEEN0_IMSIC)) {
+            vgein = get_field(env->hstatus, HSTATUS_VGEIN);
+        }
+    }
 
     if (ISELECT_IPRIO0 <= isel && isel <= ISELECT_IPRIO15) {
         /* Local interrupt priority registers not available for VS-mode */
         if (!virt) {
+            if (priv == PRV_S && cpu->cfg.ext_smstateen &&
+                !(env->hstateen[0] & 1UL << SMSTATEEN0_AIA)) {
+                goto done;
+            }
             ret = rmw_iprio(riscv_cpu_mxl_bits(env),
                             isel, iprio, val, new_val, wr_mask,
                             (priv == PRV_M) ? IRQ_M_EXT : IRQ_S_EXT);
@@ -1279,6 +1343,13 @@ static int rmw_xsetclreinum(CPURISCVState *env, int csrno, target_ulong *val,
     int ret = -EINVAL;
     bool set, pend, virt;
     target_ulong priv, isel, vgein, xlen, nval, wmask;
+    RISCVException excp;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    excp = smstateen_aia_acc_ok(env, csrno);
+    if (excp != RISCV_EXCP_NONE) {
+        return excp;
+    }
 
     /* Translate CSR number for VS-mode */
     csrno = aia_xlate_vs_csrno(env, csrno);
@@ -1397,6 +1468,13 @@ static int rmw_xtopei(CPURISCVState *env, int csrno, target_ulong *val,
     bool virt;
     int ret = -EINVAL;
     target_ulong priv, vgein;
+    RISCVException excp;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    excp = smstateen_aia_acc_ok(env, csrno);
+    if (excp != RISCV_EXCP_NONE) {
+        return excp;
+    }
 
     /* Translate CSR number for VS-mode */
     csrno = aia_xlate_vs_csrno(env, csrno);
@@ -1708,6 +1786,12 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
         wr_mask |= 1UL << SMSTATEEN0_FCSR;
     }
 
+    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
+        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
+                | (1UL << SMSTATEEN0_AIA)
+                | (1UL << SMSTATEEN0_SVSLCT);
+    }
+
     write_smstateen(env, reg, wr_mask, new_val);
 
     return RISCV_EXCP_NONE;
@@ -1736,6 +1820,12 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
         wr_mask |= 1UL << SMSTATEEN0_FCSR;
     }
 
+    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
+        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
+                | (1UL << SMSTATEEN0_AIA)
+                | (1UL << SMSTATEEN0_SVSLCT);
+    }
+
     write_smstateen(env, reg, wr_mask, val);
 
     return RISCV_EXCP_NONE;
@@ -1761,6 +1851,12 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
         wr_mask |= 1UL << SMSTATEEN0_FCSR;
     }
 
+    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
+        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
+                | (1UL << SMSTATEEN0_AIA)
+                | (1UL << SMSTATEEN0_SVSLCT);
+    }
+
     reg = &env->hstateen[index];
     wr_mask &= env->mstateen[index];
     write_smstateen(env, reg, wr_mask, new_val);
@@ -1789,6 +1885,12 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
         wr_mask |= 1UL << SMSTATEEN0_FCSR;
     }
 
+    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
+        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
+                | (1UL << SMSTATEEN0_AIA)
+                | (1UL << SMSTATEEN0_SVSLCT);
+    }
+
     reg = &env->hstateen[index];
     val = (uint64_t)new_val << 32;
     val |= *reg & 0xFFFFFFFF;
@@ -1979,6 +2081,12 @@ static RISCVException rmw_vsieh(CPURISCVState *env, int csrno,
     uint64_t rval;
     RISCVException ret;
 
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     ret = rmw_vsie64(env, csrno, &rval,
         ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
     if (ret_val) {
@@ -2033,6 +2141,12 @@ static RISCVException rmw_sieh(CPURISCVState *env, int csrno,
     uint64_t rval;
     RISCVException ret;
 
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     ret = rmw_sie64(env, csrno, &rval,
         ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
     if (ret_val) {
@@ -2195,6 +2309,12 @@ static RISCVException rmw_vsiph(CPURISCVState *env, int csrno,
     uint64_t rval;
     RISCVException ret;
 
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     ret = rmw_vsip64(env, csrno, &rval,
         ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
     if (ret_val) {
@@ -2249,6 +2369,12 @@ static RISCVException rmw_siph(CPURISCVState *env, int csrno,
     uint64_t rval;
     RISCVException ret;
 
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     ret = rmw_sip64(env, csrno, &rval,
         ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
     if (ret_val) {
@@ -2441,6 +2567,10 @@ static RISCVException read_hstatus(CPURISCVState *env, int csrno,
 static RISCVException write_hstatus(CPURISCVState *env, int csrno,
                                     target_ulong val)
 {
+    if (smstateen_aia_acc_ok(env, csrno) != RISCV_EXCP_NONE) {
+        val &= ~HSTATUS_VGEIN;
+    }
+
     env->hstatus = val;
     if (riscv_cpu_mxl(env) != MXL_RV32 && get_field(val, HSTATUS_VSXL) != 2) {
         qemu_log_mask(LOG_UNIMP, "QEMU does not support mixed HSXLEN options.");
@@ -2501,6 +2631,12 @@ static RISCVException rmw_hidelegh(CPURISCVState *env, int csrno,
     uint64_t rval;
     RISCVException ret;
 
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     ret = rmw_hideleg64(env, csrno, &rval,
         ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
     if (ret_val) {
@@ -2547,6 +2683,12 @@ static RISCVException rmw_hviph(CPURISCVState *env, int csrno,
     uint64_t rval;
     RISCVException ret;
 
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     ret = rmw_hvip64(env, csrno, &rval,
         ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
     if (ret_val) {
@@ -2601,6 +2743,13 @@ static RISCVException write_hcounteren(CPURISCVState *env, int csrno,
 static RISCVException read_hgeie(CPURISCVState *env, int csrno,
                                  target_ulong *val)
 {
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     if (val) {
         *val = env->hgeie;
     }
@@ -2610,6 +2759,13 @@ static RISCVException read_hgeie(CPURISCVState *env, int csrno,
 static RISCVException write_hgeie(CPURISCVState *env, int csrno,
                                   target_ulong val)
 {
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     /* Only GEILEN:1 bits implemented and BIT0 is never implemented */
     val &= ((((target_ulong)1) << env->geilen) - 1) << 1;
     env->hgeie = val;
@@ -2649,6 +2805,13 @@ static RISCVException write_htinst(CPURISCVState *env, int csrno,
 static RISCVException read_hgeip(CPURISCVState *env, int csrno,
                                  target_ulong *val)
 {
+    RISCVException ret;
+
+    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     if (val) {
         *val = env->hgeip;
     }
@@ -2719,12 +2882,28 @@ static RISCVException write_htimedeltah(CPURISCVState *env, int csrno,
 
 static int read_hvictl(CPURISCVState *env, int csrno, target_ulong *val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     *val = env->hvictl;
     return RISCV_EXCP_NONE;
 }
 
 static int write_hvictl(CPURISCVState *env, int csrno, target_ulong val)
 {
+    RISCVException ret = RISCV_EXCP_NONE;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     env->hvictl = val & HVICTL_VALID_MASK;
     return RISCV_EXCP_NONE;
 }
@@ -2783,41 +2962,105 @@ static int write_hvipriox(CPURISCVState *env, int first_index,
 
 static int read_hviprio1(CPURISCVState *env, int csrno, target_ulong *val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return read_hvipriox(env, 0, env->hviprio, val);
 }
 
 static int write_hviprio1(CPURISCVState *env, int csrno, target_ulong val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return write_hvipriox(env, 0, env->hviprio, val);
 }
 
 static int read_hviprio1h(CPURISCVState *env, int csrno, target_ulong *val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return read_hvipriox(env, 4, env->hviprio, val);
 }
 
 static int write_hviprio1h(CPURISCVState *env, int csrno, target_ulong val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return write_hvipriox(env, 4, env->hviprio, val);
 }
 
 static int read_hviprio2(CPURISCVState *env, int csrno, target_ulong *val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return read_hvipriox(env, 8, env->hviprio, val);
 }
 
 static int write_hviprio2(CPURISCVState *env, int csrno, target_ulong val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return write_hvipriox(env, 8, env->hviprio, val);
 }
 
 static int read_hviprio2h(CPURISCVState *env, int csrno, target_ulong *val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return read_hvipriox(env, 12, env->hviprio, val);
 }
 
 static int write_hviprio2h(CPURISCVState *env, int csrno, target_ulong val)
 {
+    RISCVException ret;
+
+    /* Check if smstateen is enabled and this access is allowed */
+    ret = smstateen_aia_acc_ok(env, csrno);
+    if (ret != RISCV_EXCP_NONE) {
+        return ret;
+    }
+
     return write_hvipriox(env, 12, env->hviprio, val);
 }
 
-- 
2.25.1

Re: [RFC PATCH v5 4/4] target/riscv: smstateen check for AIA/IMSIC

[Alistair Francis]

On Sat, Jun 4, 2022 at 2:15 AM Mayuresh Chitale
<mchitale@ventanamicro.com> wrote:
>
> If smstateen is implemented then accesses to AIA
> registers CSRS, IMSIC CSRs and other IMSIC registers
> is controlled by setting of corresponding bits in
> mstateen/hstateen registers. Otherwise an illegal
> instruction trap or virtual instruction trap is
> generated.
>
> Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> ---
>  target/riscv/csr.c | 253 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 248 insertions(+), 5 deletions(-)
>
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 8bbbed38ff..213b3c17ff 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -39,6 +39,7 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops)
>  }
>
>  /* Predicates */
> +#if !defined(CONFIG_USER_ONLY)

This should just be in the original patch.

>  static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
>  {
>      CPUState *cs = env_cpu(env);
> @@ -49,7 +50,6 @@ static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
>          return RISCV_EXCP_NONE;
>      }
>
> -#if !defined(CONFIG_USER_ONLY)
>      if (!(env->mstateen[0] & 1UL << bit)) {
>          return RISCV_EXCP_ILLEGAL_INST;
>      }
> @@ -65,11 +65,57 @@ static RISCVException smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
>              return RISCV_EXCP_ILLEGAL_INST;
>          }
>      }
> -#endif
> -
>      return RISCV_EXCP_NONE;
>  }
>
> +static RISCVException smstateen_aia_acc_ok(CPURISCVState *env, int csrno)

The spec doesn't mention the effects on AIA, it just says that some
bits are reserved. How do you know what should happen here?

Alistair

> +{
> +    int bit, mode;
> +
> +    switch (csrno) {
> +    case CSR_SSETEIPNUM:
> +    case CSR_SCLREIPNUM:
> +    case CSR_SSETEIENUM:
> +    case CSR_SCLREIENUM:
> +    case CSR_STOPEI:
> +    case CSR_VSSETEIPNUM:
> +    case CSR_VSCLREIPNUM:
> +    case CSR_VSSETEIENUM:
> +    case CSR_VSCLREIENUM:
> +    case CSR_VSTOPEI:
> +    case CSR_HSTATUS:
> +        mode = PRV_S;
> +        bit = SMSTATEEN0_IMSIC;
> +        break;
> +
> +    case CSR_SIEH:
> +    case CSR_SIPH:
> +    case CSR_HVIPH:
> +    case CSR_HVICTL:
> +    case CSR_HVIPRIO1:
> +    case CSR_HVIPRIO2:
> +    case CSR_HVIPRIO1H:
> +    case CSR_HVIPRIO2H:
> +    case CSR_VSIEH:
> +    case CSR_VSIPH:
> +        mode = PRV_S;
> +        bit = SMSTATEEN0_AIA;
> +        break;
> +
> +    case CSR_SISELECT:
> +    case CSR_VSISELECT:
> +        mode = PRV_S;
> +        bit = SMSTATEEN0_SVSLCT;
> +        break;
> +
> +    default:
> +        return RISCV_EXCP_NONE;
> +    }
> +
> +    return smstateen_acc_ok(env, mode, bit);
> +}
> +#endif
> +
>  static RISCVException fs(CPURISCVState *env, int csrno)
>  {
>  #if !defined(CONFIG_USER_ONLY)
> @@ -1130,6 +1176,13 @@ static int rmw_xiselect(CPURISCVState *env, int csrno, target_ulong *val,
>                          target_ulong new_val, target_ulong wr_mask)
>  {
>      target_ulong *iselect;
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
>
>      /* Translate CSR number for VS-mode */
>      csrno = aia_xlate_vs_csrno(env, csrno);
> @@ -1212,7 +1265,9 @@ static int rmw_xireg(CPURISCVState *env, int csrno, target_ulong *val,
>      bool virt;
>      uint8_t *iprio;
>      int ret = -EINVAL;
> -    target_ulong priv, isel, vgein;
> +    target_ulong priv, isel, vgein = 0;
> +    CPUState *cs = env_cpu(env);
> +    RISCVCPU *cpu = RISCV_CPU(cs);
>
>      /* Translate CSR number for VS-mode */
>      csrno = aia_xlate_vs_csrno(env, csrno);
> @@ -1241,11 +1296,20 @@ static int rmw_xireg(CPURISCVState *env, int csrno, target_ulong *val,
>      };
>
>      /* Find the selected guest interrupt file */
> -    vgein = (virt) ? get_field(env->hstatus, HSTATUS_VGEIN) : 0;
> +    if (virt) {
> +        if (!cpu->cfg.ext_smstateen ||
> +                (env->hstateen[0] & 1UL << SMSTATEEN0_IMSIC)) {
> +            vgein = get_field(env->hstatus, HSTATUS_VGEIN);
> +        }
> +    }
>
>      if (ISELECT_IPRIO0 <= isel && isel <= ISELECT_IPRIO15) {
>          /* Local interrupt priority registers not available for VS-mode */
>          if (!virt) {
> +            if (priv == PRV_S && cpu->cfg.ext_smstateen &&
> +                !(env->hstateen[0] & 1UL << SMSTATEEN0_AIA)) {
> +                goto done;
> +            }
>              ret = rmw_iprio(riscv_cpu_mxl_bits(env),
>                              isel, iprio, val, new_val, wr_mask,
>                              (priv == PRV_M) ? IRQ_M_EXT : IRQ_S_EXT);
> @@ -1279,6 +1343,13 @@ static int rmw_xsetclreinum(CPURISCVState *env, int csrno, target_ulong *val,
>      int ret = -EINVAL;
>      bool set, pend, virt;
>      target_ulong priv, isel, vgein, xlen, nval, wmask;
> +    RISCVException excp;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    excp = smstateen_aia_acc_ok(env, csrno);
> +    if (excp != RISCV_EXCP_NONE) {
> +        return excp;
> +    }
>
>      /* Translate CSR number for VS-mode */
>      csrno = aia_xlate_vs_csrno(env, csrno);
> @@ -1397,6 +1468,13 @@ static int rmw_xtopei(CPURISCVState *env, int csrno, target_ulong *val,
>      bool virt;
>      int ret = -EINVAL;
>      target_ulong priv, vgein;
> +    RISCVException excp;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    excp = smstateen_aia_acc_ok(env, csrno);
> +    if (excp != RISCV_EXCP_NONE) {
> +        return excp;
> +    }
>
>      /* Translate CSR number for VS-mode */
>      csrno = aia_xlate_vs_csrno(env, csrno);
> @@ -1708,6 +1786,12 @@ static RISCVException write_mstateen(CPURISCVState *env, int csrno,
>          wr_mask |= 1UL << SMSTATEEN0_FCSR;
>      }
>
> +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> +                | (1UL << SMSTATEEN0_AIA)
> +                | (1UL << SMSTATEEN0_SVSLCT);
> +    }
> +
>      write_smstateen(env, reg, wr_mask, new_val);
>
>      return RISCV_EXCP_NONE;
> @@ -1736,6 +1820,12 @@ static RISCVException write_mstateenh(CPURISCVState *env, int csrno,
>          wr_mask |= 1UL << SMSTATEEN0_FCSR;
>      }
>
> +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> +                | (1UL << SMSTATEEN0_AIA)
> +                | (1UL << SMSTATEEN0_SVSLCT);
> +    }
> +
>      write_smstateen(env, reg, wr_mask, val);
>
>      return RISCV_EXCP_NONE;
> @@ -1761,6 +1851,12 @@ static RISCVException write_hstateen(CPURISCVState *env, int csrno,
>          wr_mask |= 1UL << SMSTATEEN0_FCSR;
>      }
>
> +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> +                | (1UL << SMSTATEEN0_AIA)
> +                | (1UL << SMSTATEEN0_SVSLCT);
> +    }
> +
>      reg = &env->hstateen[index];
>      wr_mask &= env->mstateen[index];
>      write_smstateen(env, reg, wr_mask, new_val);
> @@ -1789,6 +1885,12 @@ static RISCVException write_hstateenh(CPURISCVState *env, int csrno,
>          wr_mask |= 1UL << SMSTATEEN0_FCSR;
>      }
>
> +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> +                | (1UL << SMSTATEEN0_AIA)
> +                | (1UL << SMSTATEEN0_SVSLCT);
> +    }
> +
>      reg = &env->hstateen[index];
>      val = (uint64_t)new_val << 32;
>      val |= *reg & 0xFFFFFFFF;
> @@ -1979,6 +2081,12 @@ static RISCVException rmw_vsieh(CPURISCVState *env, int csrno,
>      uint64_t rval;
>      RISCVException ret;
>
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      ret = rmw_vsie64(env, csrno, &rval,
>          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
>      if (ret_val) {
> @@ -2033,6 +2141,12 @@ static RISCVException rmw_sieh(CPURISCVState *env, int csrno,
>      uint64_t rval;
>      RISCVException ret;
>
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      ret = rmw_sie64(env, csrno, &rval,
>          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
>      if (ret_val) {
> @@ -2195,6 +2309,12 @@ static RISCVException rmw_vsiph(CPURISCVState *env, int csrno,
>      uint64_t rval;
>      RISCVException ret;
>
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      ret = rmw_vsip64(env, csrno, &rval,
>          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
>      if (ret_val) {
> @@ -2249,6 +2369,12 @@ static RISCVException rmw_siph(CPURISCVState *env, int csrno,
>      uint64_t rval;
>      RISCVException ret;
>
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      ret = rmw_sip64(env, csrno, &rval,
>          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
>      if (ret_val) {
> @@ -2441,6 +2567,10 @@ static RISCVException read_hstatus(CPURISCVState *env, int csrno,
>  static RISCVException write_hstatus(CPURISCVState *env, int csrno,
>                                      target_ulong val)
>  {
> +    if (smstateen_aia_acc_ok(env, csrno) != RISCV_EXCP_NONE) {
> +        val &= ~HSTATUS_VGEIN;
> +    }
> +
>      env->hstatus = val;
>      if (riscv_cpu_mxl(env) != MXL_RV32 && get_field(val, HSTATUS_VSXL) != 2) {
>          qemu_log_mask(LOG_UNIMP, "QEMU does not support mixed HSXLEN options.");
> @@ -2501,6 +2631,12 @@ static RISCVException rmw_hidelegh(CPURISCVState *env, int csrno,
>      uint64_t rval;
>      RISCVException ret;
>
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      ret = rmw_hideleg64(env, csrno, &rval,
>          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
>      if (ret_val) {
> @@ -2547,6 +2683,12 @@ static RISCVException rmw_hviph(CPURISCVState *env, int csrno,
>      uint64_t rval;
>      RISCVException ret;
>
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      ret = rmw_hvip64(env, csrno, &rval,
>          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
>      if (ret_val) {
> @@ -2601,6 +2743,13 @@ static RISCVException write_hcounteren(CPURISCVState *env, int csrno,
>  static RISCVException read_hgeie(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      if (val) {
>          *val = env->hgeie;
>      }
> @@ -2610,6 +2759,13 @@ static RISCVException read_hgeie(CPURISCVState *env, int csrno,
>  static RISCVException write_hgeie(CPURISCVState *env, int csrno,
>                                    target_ulong val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      /* Only GEILEN:1 bits implemented and BIT0 is never implemented */
>      val &= ((((target_ulong)1) << env->geilen) - 1) << 1;
>      env->hgeie = val;
> @@ -2649,6 +2805,13 @@ static RISCVException write_htinst(CPURISCVState *env, int csrno,
>  static RISCVException read_hgeip(CPURISCVState *env, int csrno,
>                                   target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      if (val) {
>          *val = env->hgeip;
>      }
> @@ -2719,12 +2882,28 @@ static RISCVException write_htimedeltah(CPURISCVState *env, int csrno,
>
>  static int read_hvictl(CPURISCVState *env, int csrno, target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      *val = env->hvictl;
>      return RISCV_EXCP_NONE;
>  }
>
>  static int write_hvictl(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +    RISCVException ret = RISCV_EXCP_NONE;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      env->hvictl = val & HVICTL_VALID_MASK;
>      return RISCV_EXCP_NONE;
>  }
> @@ -2783,41 +2962,105 @@ static int write_hvipriox(CPURISCVState *env, int first_index,
>
>  static int read_hviprio1(CPURISCVState *env, int csrno, target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return read_hvipriox(env, 0, env->hviprio, val);
>  }
>
>  static int write_hviprio1(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return write_hvipriox(env, 0, env->hviprio, val);
>  }
>
>  static int read_hviprio1h(CPURISCVState *env, int csrno, target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return read_hvipriox(env, 4, env->hviprio, val);
>  }
>
>  static int write_hviprio1h(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return write_hvipriox(env, 4, env->hviprio, val);
>  }
>
>  static int read_hviprio2(CPURISCVState *env, int csrno, target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return read_hvipriox(env, 8, env->hviprio, val);
>  }
>
>  static int write_hviprio2(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return write_hvipriox(env, 8, env->hviprio, val);
>  }
>
>  static int read_hviprio2h(CPURISCVState *env, int csrno, target_ulong *val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return read_hvipriox(env, 12, env->hviprio, val);
>  }
>
>  static int write_hviprio2h(CPURISCVState *env, int csrno, target_ulong val)
>  {
> +    RISCVException ret;
> +
> +    /* Check if smstateen is enabled and this access is allowed */
> +    ret = smstateen_aia_acc_ok(env, csrno);
> +    if (ret != RISCV_EXCP_NONE) {
> +        return ret;
> +    }
> +
>      return write_hvipriox(env, 12, env->hviprio, val);
>  }
>
> --
> 2.25.1
>
>

Re: [RFC PATCH v5 4/4] target/riscv: smstateen check for AIA/IMSIC

[Mayuresh Chitale]

On Thu, 2022-06-16 at 17:18 +1000, Alistair Francis wrote:
> On Sat, Jun 4, 2022 at 2:15 AM Mayuresh Chitale
> <mchitale@ventanamicro.com> wrote:
> > If smstateen is implemented then accesses to AIA
> > registers CSRS, IMSIC CSRs and other IMSIC registers
> > is controlled by setting of corresponding bits in
> > mstateen/hstateen registers. Otherwise an illegal
> > instruction trap or virtual instruction trap is
> > generated.
> > 
> > Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
> > ---
> >  target/riscv/csr.c | 253
> > ++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 248 insertions(+), 5 deletions(-)
> > 
> > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > index 8bbbed38ff..213b3c17ff 100644
> > --- a/target/riscv/csr.c
> > +++ b/target/riscv/csr.c
> > @@ -39,6 +39,7 @@ void riscv_set_csr_ops(int csrno,
> > riscv_csr_operations *ops)
> >  }
> > 
> >  /* Predicates */
> > +#if !defined(CONFIG_USER_ONLY)
> 
> This should just be in the original patch.

I will modify the second patch. 
> 
> >  static RISCVException smstateen_acc_ok(CPURISCVState *env, int
> > mode, int bit)
> >  {
> >      CPUState *cs = env_cpu(env);
> > @@ -49,7 +50,6 @@ static RISCVException
> > smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
> >          return RISCV_EXCP_NONE;
> >      }
> > 
> > -#if !defined(CONFIG_USER_ONLY)
> >      if (!(env->mstateen[0] & 1UL << bit)) {
> >          return RISCV_EXCP_ILLEGAL_INST;
> >      }
> > @@ -65,11 +65,57 @@ static RISCVException
> > smstateen_acc_ok(CPURISCVState *env, int mode, int bit)
> >              return RISCV_EXCP_ILLEGAL_INST;
> >          }
> >      }
> > -#endif
> > -
> >      return RISCV_EXCP_NONE;
> >  }
> > 
> > +static RISCVException smstateen_aia_acc_ok(CPURISCVState *env, int
> > csrno)
> 
> The spec doesn't mention the effects on AIA, it just says that some
> bits are reserved. How do you know what should happen here?
Actually these bits were defined in an earlier version of the spec but
I can drop this patch for now and resend once those bits get defined
again.
> 
> Alistair
> 
> > +{
> > +    int bit, mode;
> > +
> > +    switch (csrno) {
> > +    case CSR_SSETEIPNUM:
> > +    case CSR_SCLREIPNUM:
> > +    case CSR_SSETEIENUM:
> > +    case CSR_SCLREIENUM:
> > +    case CSR_STOPEI:
> > +    case CSR_VSSETEIPNUM:
> > +    case CSR_VSCLREIPNUM:
> > +    case CSR_VSSETEIENUM:
> > +    case CSR_VSCLREIENUM:
> > +    case CSR_VSTOPEI:
> > +    case CSR_HSTATUS:
> > +        mode = PRV_S;
> > +        bit = SMSTATEEN0_IMSIC;
> > +        break;
> > +
> > +    case CSR_SIEH:
> > +    case CSR_SIPH:
> > +    case CSR_HVIPH:
> > +    case CSR_HVICTL:
> > +    case CSR_HVIPRIO1:
> > +    case CSR_HVIPRIO2:
> > +    case CSR_HVIPRIO1H:
> > +    case CSR_HVIPRIO2H:
> > +    case CSR_VSIEH:
> > +    case CSR_VSIPH:
> > +        mode = PRV_S;
> > +        bit = SMSTATEEN0_AIA;
> > +        break;
> > +
> > +    case CSR_SISELECT:
> > +    case CSR_VSISELECT:
> > +        mode = PRV_S;
> > +        bit = SMSTATEEN0_SVSLCT;
> > +        break;
> > +
> > +    default:
> > +        return RISCV_EXCP_NONE;
> > +    }
> > +
> > +    return smstateen_acc_ok(env, mode, bit);
> > +}
> > +#endif
> > +
> >  static RISCVException fs(CPURISCVState *env, int csrno)
> >  {
> >  #if !defined(CONFIG_USER_ONLY)
> > @@ -1130,6 +1176,13 @@ static int rmw_xiselect(CPURISCVState *env,
> > int csrno, target_ulong *val,
> >                          target_ulong new_val, target_ulong
> > wr_mask)
> >  {
> >      target_ulong *iselect;
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > 
> >      /* Translate CSR number for VS-mode */
> >      csrno = aia_xlate_vs_csrno(env, csrno);
> > @@ -1212,7 +1265,9 @@ static int rmw_xireg(CPURISCVState *env, int
> > csrno, target_ulong *val,
> >      bool virt;
> >      uint8_t *iprio;
> >      int ret = -EINVAL;
> > -    target_ulong priv, isel, vgein;
> > +    target_ulong priv, isel, vgein = 0;
> > +    CPUState *cs = env_cpu(env);
> > +    RISCVCPU *cpu = RISCV_CPU(cs);
> > 
> >      /* Translate CSR number for VS-mode */
> >      csrno = aia_xlate_vs_csrno(env, csrno);
> > @@ -1241,11 +1296,20 @@ static int rmw_xireg(CPURISCVState *env,
> > int csrno, target_ulong *val,
> >      };
> > 
> >      /* Find the selected guest interrupt file */
> > -    vgein = (virt) ? get_field(env->hstatus, HSTATUS_VGEIN) : 0;
> > +    if (virt) {
> > +        if (!cpu->cfg.ext_smstateen ||
> > +                (env->hstateen[0] & 1UL << SMSTATEEN0_IMSIC)) {
> > +            vgein = get_field(env->hstatus, HSTATUS_VGEIN);
> > +        }
> > +    }
> > 
> >      if (ISELECT_IPRIO0 <= isel && isel <= ISELECT_IPRIO15) {
> >          /* Local interrupt priority registers not available for
> > VS-mode */
> >          if (!virt) {
> > +            if (priv == PRV_S && cpu->cfg.ext_smstateen &&
> > +                !(env->hstateen[0] & 1UL << SMSTATEEN0_AIA)) {
> > +                goto done;
> > +            }
> >              ret = rmw_iprio(riscv_cpu_mxl_bits(env),
> >                              isel, iprio, val, new_val, wr_mask,
> >                              (priv == PRV_M) ? IRQ_M_EXT :
> > IRQ_S_EXT);
> > @@ -1279,6 +1343,13 @@ static int rmw_xsetclreinum(CPURISCVState
> > *env, int csrno, target_ulong *val,
> >      int ret = -EINVAL;
> >      bool set, pend, virt;
> >      target_ulong priv, isel, vgein, xlen, nval, wmask;
> > +    RISCVException excp;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    excp = smstateen_aia_acc_ok(env, csrno);
> > +    if (excp != RISCV_EXCP_NONE) {
> > +        return excp;
> > +    }
> > 
> >      /* Translate CSR number for VS-mode */
> >      csrno = aia_xlate_vs_csrno(env, csrno);
> > @@ -1397,6 +1468,13 @@ static int rmw_xtopei(CPURISCVState *env,
> > int csrno, target_ulong *val,
> >      bool virt;
> >      int ret = -EINVAL;
> >      target_ulong priv, vgein;
> > +    RISCVException excp;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    excp = smstateen_aia_acc_ok(env, csrno);
> > +    if (excp != RISCV_EXCP_NONE) {
> > +        return excp;
> > +    }
> > 
> >      /* Translate CSR number for VS-mode */
> >      csrno = aia_xlate_vs_csrno(env, csrno);
> > @@ -1708,6 +1786,12 @@ static RISCVException
> > write_mstateen(CPURISCVState *env, int csrno,
> >          wr_mask |= 1UL << SMSTATEEN0_FCSR;
> >      }
> > 
> > +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> > +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> > +                | (1UL << SMSTATEEN0_AIA)
> > +                | (1UL << SMSTATEEN0_SVSLCT);
> > +    }
> > +
> >      write_smstateen(env, reg, wr_mask, new_val);
> > 
> >      return RISCV_EXCP_NONE;
> > @@ -1736,6 +1820,12 @@ static RISCVException
> > write_mstateenh(CPURISCVState *env, int csrno,
> >          wr_mask |= 1UL << SMSTATEEN0_FCSR;
> >      }
> > 
> > +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> > +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> > +                | (1UL << SMSTATEEN0_AIA)
> > +                | (1UL << SMSTATEEN0_SVSLCT);
> > +    }
> > +
> >      write_smstateen(env, reg, wr_mask, val);
> > 
> >      return RISCV_EXCP_NONE;
> > @@ -1761,6 +1851,12 @@ static RISCVException
> > write_hstateen(CPURISCVState *env, int csrno,
> >          wr_mask |= 1UL << SMSTATEEN0_FCSR;
> >      }
> > 
> > +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> > +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> > +                | (1UL << SMSTATEEN0_AIA)
> > +                | (1UL << SMSTATEEN0_SVSLCT);
> > +    }
> > +
> >      reg = &env->hstateen[index];
> >      wr_mask &= env->mstateen[index];
> >      write_smstateen(env, reg, wr_mask, new_val);
> > @@ -1789,6 +1885,12 @@ static RISCVException
> > write_hstateenh(CPURISCVState *env, int csrno,
> >          wr_mask |= 1UL << SMSTATEEN0_FCSR;
> >      }
> > 
> > +    if (riscv_feature(env, RISCV_FEATURE_AIA)) {
> > +        wr_mask |= (1UL << SMSTATEEN0_IMSIC)
> > +                | (1UL << SMSTATEEN0_AIA)
> > +                | (1UL << SMSTATEEN0_SVSLCT);
> > +    }
> > +
> >      reg = &env->hstateen[index];
> >      val = (uint64_t)new_val << 32;
> >      val |= *reg & 0xFFFFFFFF;
> > @@ -1979,6 +2081,12 @@ static RISCVException
> > rmw_vsieh(CPURISCVState *env, int csrno,
> >      uint64_t rval;
> >      RISCVException ret;
> > 
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      ret = rmw_vsie64(env, csrno, &rval,
> >          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
> >      if (ret_val) {
> > @@ -2033,6 +2141,12 @@ static RISCVException rmw_sieh(CPURISCVState
> > *env, int csrno,
> >      uint64_t rval;
> >      RISCVException ret;
> > 
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      ret = rmw_sie64(env, csrno, &rval,
> >          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
> >      if (ret_val) {
> > @@ -2195,6 +2309,12 @@ static RISCVException
> > rmw_vsiph(CPURISCVState *env, int csrno,
> >      uint64_t rval;
> >      RISCVException ret;
> > 
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      ret = rmw_vsip64(env, csrno, &rval,
> >          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
> >      if (ret_val) {
> > @@ -2249,6 +2369,12 @@ static RISCVException rmw_siph(CPURISCVState
> > *env, int csrno,
> >      uint64_t rval;
> >      RISCVException ret;
> > 
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      ret = rmw_sip64(env, csrno, &rval,
> >          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
> >      if (ret_val) {
> > @@ -2441,6 +2567,10 @@ static RISCVException
> > read_hstatus(CPURISCVState *env, int csrno,
> >  static RISCVException write_hstatus(CPURISCVState *env, int csrno,
> >                                      target_ulong val)
> >  {
> > +    if (smstateen_aia_acc_ok(env, csrno) != RISCV_EXCP_NONE) {
> > +        val &= ~HSTATUS_VGEIN;
> > +    }
> > +
> >      env->hstatus = val;
> >      if (riscv_cpu_mxl(env) != MXL_RV32 && get_field(val,
> > HSTATUS_VSXL) != 2) {
> >          qemu_log_mask(LOG_UNIMP, "QEMU does not support mixed
> > HSXLEN options.");
> > @@ -2501,6 +2631,12 @@ static RISCVException
> > rmw_hidelegh(CPURISCVState *env, int csrno,
> >      uint64_t rval;
> >      RISCVException ret;
> > 
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      ret = rmw_hideleg64(env, csrno, &rval,
> >          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
> >      if (ret_val) {
> > @@ -2547,6 +2683,12 @@ static RISCVException
> > rmw_hviph(CPURISCVState *env, int csrno,
> >      uint64_t rval;
> >      RISCVException ret;
> > 
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      ret = rmw_hvip64(env, csrno, &rval,
> >          ((uint64_t)new_val) << 32, ((uint64_t)wr_mask) << 32);
> >      if (ret_val) {
> > @@ -2601,6 +2743,13 @@ static RISCVException
> > write_hcounteren(CPURISCVState *env, int csrno,
> >  static RISCVException read_hgeie(CPURISCVState *env, int csrno,
> >                                   target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      if (val) {
> >          *val = env->hgeie;
> >      }
> > @@ -2610,6 +2759,13 @@ static RISCVException
> > read_hgeie(CPURISCVState *env, int csrno,
> >  static RISCVException write_hgeie(CPURISCVState *env, int csrno,
> >                                    target_ulong val)
> >  {
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      /* Only GEILEN:1 bits implemented and BIT0 is never
> > implemented */
> >      val &= ((((target_ulong)1) << env->geilen) - 1) << 1;
> >      env->hgeie = val;
> > @@ -2649,6 +2805,13 @@ static RISCVException
> > write_htinst(CPURISCVState *env, int csrno,
> >  static RISCVException read_hgeip(CPURISCVState *env, int csrno,
> >                                   target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    ret = smstateen_acc_ok(env, PRV_S, SMSTATEEN0_IMSIC);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      if (val) {
> >          *val = env->hgeip;
> >      }
> > @@ -2719,12 +2882,28 @@ static RISCVException
> > write_htimedeltah(CPURISCVState *env, int csrno,
> > 
> >  static int read_hvictl(CPURISCVState *env, int csrno, target_ulong
> > *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      *val = env->hvictl;
> >      return RISCV_EXCP_NONE;
> >  }
> > 
> >  static int write_hvictl(CPURISCVState *env, int csrno,
> > target_ulong val)
> >  {
> > +    RISCVException ret = RISCV_EXCP_NONE;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      env->hvictl = val & HVICTL_VALID_MASK;
> >      return RISCV_EXCP_NONE;
> >  }
> > @@ -2783,41 +2962,105 @@ static int write_hvipriox(CPURISCVState
> > *env, int first_index,
> > 
> >  static int read_hviprio1(CPURISCVState *env, int csrno,
> > target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return read_hvipriox(env, 0, env->hviprio, val);
> >  }
> > 
> >  static int write_hviprio1(CPURISCVState *env, int csrno,
> > target_ulong val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return write_hvipriox(env, 0, env->hviprio, val);
> >  }
> > 
> >  static int read_hviprio1h(CPURISCVState *env, int csrno,
> > target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return read_hvipriox(env, 4, env->hviprio, val);
> >  }
> > 
> >  static int write_hviprio1h(CPURISCVState *env, int csrno,
> > target_ulong val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return write_hvipriox(env, 4, env->hviprio, val);
> >  }
> > 
> >  static int read_hviprio2(CPURISCVState *env, int csrno,
> > target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return read_hvipriox(env, 8, env->hviprio, val);
> >  }
> > 
> >  static int write_hviprio2(CPURISCVState *env, int csrno,
> > target_ulong val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return write_hvipriox(env, 8, env->hviprio, val);
> >  }
> > 
> >  static int read_hviprio2h(CPURISCVState *env, int csrno,
> > target_ulong *val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return read_hvipriox(env, 12, env->hviprio, val);
> >  }
> > 
> >  static int write_hviprio2h(CPURISCVState *env, int csrno,
> > target_ulong val)
> >  {
> > +    RISCVException ret;
> > +
> > +    /* Check if smstateen is enabled and this access is allowed */
> > +    ret = smstateen_aia_acc_ok(env, csrno);
> > +    if (ret != RISCV_EXCP_NONE) {
> > +        return ret;
> > +    }
> > +
> >      return write_hvipriox(env, 12, env->hviprio, val);
> >  }
> > 
> > --
> > 2.25.1
> > 
> >