[Qemu-devel] [PATCH 0/4] target/arm: Implement TBI for user-only

[Qemu-devel] [PATCH 0/4] target/arm: Implement TBI for user-only

[Richard Henderson]

Based-on: 20190110121736.23448-1-richard.henderson@linaro.org
aka the BTI patch set.

This is a prerequisite to implementing v8.5-MemTag.


r~


Richard Henderson (4):
  target/arm: Add TBFLAG_A64_TBID, split out gen_top_byte_ignore
  target/arm: Clean TBI for data operations in the translator
  target/arm: Compute TB_FLAGS for TBI for user-only
  target/arm: Enable TBI for user-only

 target/arm/cpu.h           |   1 +
 target/arm/internals.h     |  21 ---
 target/arm/translate.h     |   3 +-
 target/arm/cpu.c           |   6 +
 target/arm/helper.c        |  14 +-
 target/arm/translate-a64.c | 257 +++++++++++++++++++------------------
 6 files changed, 150 insertions(+), 152 deletions(-)

-- 
2.17.2

[Qemu-devel] [PATCH 1/4] target/arm: Add TBFLAG_A64_TBID, split out gen_top_byte_ignore

[Richard Henderson]

Split out gen_top_byte_ignore in preparation of handling these
data accesses; the new tbflags field is not yet honored.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/cpu.h           |  1 +
 target/arm/translate.h     |  3 ++-
 target/arm/helper.c        |  1 +
 target/arm/translate-a64.c | 40 +++++++++++++++++---------------------
 4 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 929f16dd6b..02e6dcce25 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -2996,6 +2996,7 @@ FIELD(TBFLAG_A64, ZCR_LEN, 4, 4)
 FIELD(TBFLAG_A64, PAUTH_ACTIVE, 8, 1)
 FIELD(TBFLAG_A64, BT, 9, 1)
 FIELD(TBFLAG_A64, BTYPE, 10, 2)
+FIELD(TBFLAG_A64, TBID, 12, 2)
 
 static inline bool bswap_code(bool sctlr_b)
 {
diff --git a/target/arm/translate.h b/target/arm/translate.h
index f73939d7b4..17748ddfb9 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -26,7 +26,8 @@ typedef struct DisasContext {
     int user;
 #endif
     ARMMMUIdx mmu_idx; /* MMU index to use for normal loads/stores */
-    uint8_t tbii;      /* TBI1|TBI0 for EL0/1 or TBI for EL2/3 */
+    uint8_t tbii;      /* TBI1|TBI0 for insns */
+    uint8_t tbid;      /* TBI1|TBI0 for data */
     bool ns;        /* Use non-secure CPREG bank on access */
     int fp_excp_el; /* FP exception EL or 0 if enabled */
     int sve_excp_el; /* SVE exception EL or 0 if enabled */
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 4e9ea2ed39..8c28c6d044 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -13108,6 +13108,7 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
             }
 
             flags = FIELD_DP32(flags, TBFLAG_A64, TBII, tbii);
+            flags = FIELD_DP32(flags, TBFLAG_A64, TBID, tbid);
         }
 #endif
 
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index f225517077..9548252782 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -284,31 +284,17 @@ void gen_a64_set_pc_im(uint64_t val)
     tcg_gen_movi_i64(cpu_pc, val);
 }
 
-/* Load the PC from a generic TCG variable.
- *
- * If address tagging is enabled via the TCR TBI bits, then loading
- * an address into the PC will clear out any tag in it:
- *  + for EL2 and EL3 there is only one TBI bit, and if it is set
- *    then the address is zero-extended, clearing bits [63:56]
- *  + for EL0 and EL1, TBI0 controls addresses with bit 55 == 0
- *    and TBI1 controls addressses with bit 55 == 1.
- *    If the appropriate TBI bit is set for the address then
- *    the address is sign-extended from bit 55 into bits [63:56]
- *
- * We can avoid doing this for relative-branches, because the
- * PC + offset can never overflow into the tag bits (assuming
- * that virtual addresses are less than 56 bits wide, as they
- * are currently), but we must handle it for branch-to-register.
+/*
+ * Handle Top Byte Ignore (TBI) bits.
+ * We have concatenated tbi{1,0} into tbi.
  */
-static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
+static void gen_top_byte_ignore(DisasContext *s, TCGv_i64 dst,
+                                TCGv_i64 src, int tbi)
 {
-    /* Note that TBII is TBI1:TBI0.  */
-    int tbi = s->tbii;
-
     if (s->current_el <= 1) {
         if (tbi != 0) {
             /* Sign-extend from bit 55.  */
-            tcg_gen_sextract_i64(cpu_pc, src, 0, 56);
+            tcg_gen_sextract_i64(dst, src, 0, 56);
 
             if (tbi != 3) {
                 TCGv_i64 tcg_zero = tcg_const_i64(0);
@@ -327,13 +313,22 @@ static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
     } else {
         if (tbi != 0) {
             /* Force tag byte to all zero */
-            tcg_gen_extract_i64(cpu_pc, src, 0, 56);
+            tcg_gen_extract_i64(dst, src, 0, 56);
             return;
         }
     }
 
     /* Load unmodified address */
-    tcg_gen_mov_i64(cpu_pc, src);
+    tcg_gen_mov_i64(dst, src);
+}
+
+static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
+{
+    /*
+     * If address tagging is enabled for instructions via the TCR TBI bits,
+     * then loading an address into the PC will clear out any tag.
+     */
+    gen_top_byte_ignore(s, cpu_pc, src, s->tbii);
 }
 
 typedef struct DisasCompare64 {
@@ -13981,6 +13976,7 @@ static void aarch64_tr_init_disas_context(DisasContextBase *dcbase,
     core_mmu_idx = FIELD_EX32(tb_flags, TBFLAG_ANY, MMUIDX);
     dc->mmu_idx = core_to_arm_mmu_idx(env, core_mmu_idx);
     dc->tbii = FIELD_EX32(tb_flags, TBFLAG_A64, TBII);
+    dc->tbid = FIELD_EX32(tb_flags, TBFLAG_A64, TBID);
     dc->current_el = arm_mmu_idx_to_el(dc->mmu_idx);
 #if !defined(CONFIG_USER_ONLY)
     dc->user = (dc->current_el == 0);
-- 
2.17.2

[Qemu-devel] [PATCH 2/4] target/arm: Clean TBI for data operations in the translator

[Richard Henderson]

This will allow TBI to be used in user-only mode, as well as
avoid ping-ponging the softmmu TLB when TBI is in use.  It
will also enable other armv8 extensions.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/translate-a64.c | 217 ++++++++++++++++++++-----------------
 1 file changed, 116 insertions(+), 101 deletions(-)

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 9548252782..1d9e204884 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -331,6 +331,18 @@ static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
     gen_top_byte_ignore(s, cpu_pc, src, s->tbii);
 }
 
+/*
+ * Return a "clean" address for ADDR according to TBID.
+ * This is always a fresh temporary, as we need to be able to
+ * increment this independently of a dirty write-back address.
+ */
+static TCGv_i64 clean_data_tbi(DisasContext *s, TCGv_i64 addr)
+{
+    TCGv_i64 clean = new_tmp_a64(s);
+    gen_top_byte_ignore(s, clean, addr, s->tbid);
+    return clean;
+}
+
 typedef struct DisasCompare64 {
     TCGCond cond;
     TCGv_i64 value;
@@ -2342,12 +2354,13 @@ static void gen_compare_and_swap(DisasContext *s, int rs, int rt,
     TCGv_i64 tcg_rs = cpu_reg(s, rs);
     TCGv_i64 tcg_rt = cpu_reg(s, rt);
     int memidx = get_mem_index(s);
-    TCGv_i64 addr = cpu_reg_sp(s, rn);
+    TCGv_i64 clean_addr;
 
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
-    tcg_gen_atomic_cmpxchg_i64(tcg_rs, addr, tcg_rs, tcg_rt, memidx,
+    clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
+    tcg_gen_atomic_cmpxchg_i64(tcg_rs, clean_addr, tcg_rs, tcg_rt, memidx,
                                size | MO_ALIGN | s->be_data);
 }
 
@@ -2358,12 +2371,13 @@ static void gen_compare_and_swap_pair(DisasContext *s, int rs, int rt,
     TCGv_i64 s2 = cpu_reg(s, rs + 1);
     TCGv_i64 t1 = cpu_reg(s, rt);
     TCGv_i64 t2 = cpu_reg(s, rt + 1);
-    TCGv_i64 addr = cpu_reg_sp(s, rn);
+    TCGv_i64 clean_addr;
     int memidx = get_mem_index(s);
 
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
+    clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
 
     if (size == 2) {
         TCGv_i64 cmp = tcg_temp_new_i64();
@@ -2377,7 +2391,7 @@ static void gen_compare_and_swap_pair(DisasContext *s, int rs, int rt,
             tcg_gen_concat32_i64(cmp, s2, s1);
         }
 
-        tcg_gen_atomic_cmpxchg_i64(cmp, addr, cmp, val, memidx,
+        tcg_gen_atomic_cmpxchg_i64(cmp, clean_addr, cmp, val, memidx,
                                    MO_64 | MO_ALIGN | s->be_data);
         tcg_temp_free_i64(val);
 
@@ -2391,9 +2405,11 @@ static void gen_compare_and_swap_pair(DisasContext *s, int rs, int rt,
         if (HAVE_CMPXCHG128) {
             TCGv_i32 tcg_rs = tcg_const_i32(rs);
             if (s->be_data == MO_LE) {
-                gen_helper_casp_le_parallel(cpu_env, tcg_rs, addr, t1, t2);
+                gen_helper_casp_le_parallel(cpu_env, tcg_rs,
+                                            clean_addr, t1, t2);
             } else {
-                gen_helper_casp_be_parallel(cpu_env, tcg_rs, addr, t1, t2);
+                gen_helper_casp_be_parallel(cpu_env, tcg_rs,
+                                            clean_addr, t1, t2);
             }
             tcg_temp_free_i32(tcg_rs);
         } else {
@@ -2409,10 +2425,10 @@ static void gen_compare_and_swap_pair(DisasContext *s, int rs, int rt,
         TCGv_i64 zero = tcg_const_i64(0);
 
         /* Load the two words, in memory order.  */
-        tcg_gen_qemu_ld_i64(d1, addr, memidx,
+        tcg_gen_qemu_ld_i64(d1, clean_addr, memidx,
                             MO_64 | MO_ALIGN_16 | s->be_data);
-        tcg_gen_addi_i64(a2, addr, 8);
-        tcg_gen_qemu_ld_i64(d2, addr, memidx, MO_64 | s->be_data);
+        tcg_gen_addi_i64(a2, clean_addr, 8);
+        tcg_gen_qemu_ld_i64(d2, clean_addr, memidx, MO_64 | s->be_data);
 
         /* Compare the two words, also in memory order.  */
         tcg_gen_setcond_i64(TCG_COND_EQ, c1, d1, s1);
@@ -2422,7 +2438,7 @@ static void gen_compare_and_swap_pair(DisasContext *s, int rs, int rt,
         /* If compare equal, write back new data, else write back old data.  */
         tcg_gen_movcond_i64(TCG_COND_NE, c1, c2, zero, t1, d1);
         tcg_gen_movcond_i64(TCG_COND_NE, c2, c2, zero, t2, d2);
-        tcg_gen_qemu_st_i64(c1, addr, memidx, MO_64 | s->be_data);
+        tcg_gen_qemu_st_i64(c1, clean_addr, memidx, MO_64 | s->be_data);
         tcg_gen_qemu_st_i64(c2, a2, memidx, MO_64 | s->be_data);
         tcg_temp_free_i64(a2);
         tcg_temp_free_i64(c1);
@@ -2475,7 +2491,7 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
     int is_lasr = extract32(insn, 15, 1);
     int o2_L_o1_o0 = extract32(insn, 21, 3) * 2 | is_lasr;
     int size = extract32(insn, 30, 2);
-    TCGv_i64 tcg_addr;
+    TCGv_i64 clean_addr;
 
     switch (o2_L_o1_o0) {
     case 0x0: /* STXR */
@@ -2486,8 +2502,8 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
         if (is_lasr) {
             tcg_gen_mb(TCG_MO_ALL | TCG_BAR_STRL);
         }
-        tcg_addr = read_cpu_reg_sp(s, rn, 1);
-        gen_store_exclusive(s, rs, rt, rt2, tcg_addr, size, false);
+        clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
+        gen_store_exclusive(s, rs, rt, rt2, clean_addr, size, false);
         return;
 
     case 0x4: /* LDXR */
@@ -2495,9 +2511,9 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
         if (rn == 31) {
             gen_check_sp_alignment(s);
         }
-        tcg_addr = read_cpu_reg_sp(s, rn, 1);
+        clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
         s->is_ldex = true;
-        gen_load_exclusive(s, rt, rt2, tcg_addr, size, false);
+        gen_load_exclusive(s, rt, rt2, clean_addr, size, false);
         if (is_lasr) {
             tcg_gen_mb(TCG_MO_ALL | TCG_BAR_LDAQ);
         }
@@ -2515,8 +2531,8 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
             gen_check_sp_alignment(s);
         }
         tcg_gen_mb(TCG_MO_ALL | TCG_BAR_STRL);
-        tcg_addr = read_cpu_reg_sp(s, rn, 1);
-        do_gpr_st(s, cpu_reg(s, rt), tcg_addr, size, true, rt,
+        clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
+        do_gpr_st(s, cpu_reg(s, rt), clean_addr, size, true, rt,
                   disas_ldst_compute_iss_sf(size, false, 0), is_lasr);
         return;
 
@@ -2531,8 +2547,8 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
         if (rn == 31) {
             gen_check_sp_alignment(s);
         }
-        tcg_addr = read_cpu_reg_sp(s, rn, 1);
-        do_gpr_ld(s, cpu_reg(s, rt), tcg_addr, size, false, false, true, rt,
+        clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
+        do_gpr_ld(s, cpu_reg(s, rt), clean_addr, size, false, false, true, rt,
                   disas_ldst_compute_iss_sf(size, false, 0), is_lasr);
         tcg_gen_mb(TCG_MO_ALL | TCG_BAR_LDAQ);
         return;
@@ -2545,8 +2561,8 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
             if (is_lasr) {
                 tcg_gen_mb(TCG_MO_ALL | TCG_BAR_STRL);
             }
-            tcg_addr = read_cpu_reg_sp(s, rn, 1);
-            gen_store_exclusive(s, rs, rt, rt2, tcg_addr, size, true);
+            clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
+            gen_store_exclusive(s, rs, rt, rt2, clean_addr, size, true);
             return;
         }
         if (rt2 == 31
@@ -2563,9 +2579,9 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn)
             if (rn == 31) {
                 gen_check_sp_alignment(s);
             }
-            tcg_addr = read_cpu_reg_sp(s, rn, 1);
+            clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
             s->is_ldex = true;
-            gen_load_exclusive(s, rt, rt2, tcg_addr, size, true);
+            gen_load_exclusive(s, rt, rt2, clean_addr, size, true);
             if (is_lasr) {
                 tcg_gen_mb(TCG_MO_ALL | TCG_BAR_LDAQ);
             }
@@ -2614,7 +2630,7 @@ static void disas_ld_lit(DisasContext *s, uint32_t insn)
     int opc = extract32(insn, 30, 2);
     bool is_signed = false;
     int size = 2;
-    TCGv_i64 tcg_rt, tcg_addr;
+    TCGv_i64 tcg_rt, clean_addr;
 
     if (is_vector) {
         if (opc == 3) {
@@ -2636,17 +2652,17 @@ static void disas_ld_lit(DisasContext *s, uint32_t insn)
 
     tcg_rt = cpu_reg(s, rt);
 
-    tcg_addr = tcg_const_i64((s->pc - 4) + imm);
+    clean_addr = tcg_const_i64((s->pc - 4) + imm);
     if (is_vector) {
-        do_fp_ld(s, rt, tcg_addr, size);
+        do_fp_ld(s, rt, clean_addr, size);
     } else {
         /* Only unsigned 32bit loads target 32bit registers.  */
         bool iss_sf = opc != 0;
 
-        do_gpr_ld(s, tcg_rt, tcg_addr, size, is_signed, false,
+        do_gpr_ld(s, tcg_rt, clean_addr, size, is_signed, false,
                   true, rt, iss_sf, false);
     }
-    tcg_temp_free_i64(tcg_addr);
+    tcg_temp_free_i64(clean_addr);
 }
 
 /*
@@ -2692,7 +2708,8 @@ static void disas_ldst_pair(DisasContext *s, uint32_t insn)
     bool postindex = false;
     bool wback = false;
 
-    TCGv_i64 tcg_addr; /* calculated address */
+    TCGv_i64 clean_addr, dirty_addr;
+
     int size;
 
     if (opc == 3) {
@@ -2748,23 +2765,23 @@ static void disas_ldst_pair(DisasContext *s, uint32_t insn)
         gen_check_sp_alignment(s);
     }
 
-    tcg_addr = read_cpu_reg_sp(s, rn, 1);
-
+    dirty_addr = read_cpu_reg_sp(s, rn, 1);
     if (!postindex) {
-        tcg_gen_addi_i64(tcg_addr, tcg_addr, offset);
+        tcg_gen_addi_i64(dirty_addr, dirty_addr, offset);
     }
+    clean_addr = clean_data_tbi(s, dirty_addr);
 
     if (is_vector) {
         if (is_load) {
-            do_fp_ld(s, rt, tcg_addr, size);
+            do_fp_ld(s, rt, clean_addr, size);
         } else {
-            do_fp_st(s, rt, tcg_addr, size);
+            do_fp_st(s, rt, clean_addr, size);
         }
-        tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size);
+        tcg_gen_addi_i64(clean_addr, clean_addr, 1 << size);
         if (is_load) {
-            do_fp_ld(s, rt2, tcg_addr, size);
+            do_fp_ld(s, rt2, clean_addr, size);
         } else {
-            do_fp_st(s, rt2, tcg_addr, size);
+            do_fp_st(s, rt2, clean_addr, size);
         }
     } else {
         TCGv_i64 tcg_rt = cpu_reg(s, rt);
@@ -2776,30 +2793,28 @@ static void disas_ldst_pair(DisasContext *s, uint32_t insn)
             /* Do not modify tcg_rt before recognizing any exception
              * from the second load.
              */
-            do_gpr_ld(s, tmp, tcg_addr, size, is_signed, false,
+            do_gpr_ld(s, tmp, clean_addr, size, is_signed, false,
                       false, 0, false, false);
-            tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size);
-            do_gpr_ld(s, tcg_rt2, tcg_addr, size, is_signed, false,
+            tcg_gen_addi_i64(clean_addr, clean_addr, 1 << size);
+            do_gpr_ld(s, tcg_rt2, clean_addr, size, is_signed, false,
                       false, 0, false, false);
 
             tcg_gen_mov_i64(tcg_rt, tmp);
             tcg_temp_free_i64(tmp);
         } else {
-            do_gpr_st(s, tcg_rt, tcg_addr, size,
+            do_gpr_st(s, tcg_rt, clean_addr, size,
                       false, 0, false, false);
-            tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size);
-            do_gpr_st(s, tcg_rt2, tcg_addr, size,
+            tcg_gen_addi_i64(clean_addr, clean_addr, 1 << size);
+            do_gpr_st(s, tcg_rt2, clean_addr, size,
                       false, 0, false, false);
         }
     }
 
     if (wback) {
         if (postindex) {
-            tcg_gen_addi_i64(tcg_addr, tcg_addr, offset - (1 << size));
-        } else {
-            tcg_gen_subi_i64(tcg_addr, tcg_addr, 1 << size);
+            tcg_gen_addi_i64(dirty_addr, dirty_addr, offset);
         }
-        tcg_gen_mov_i64(cpu_reg_sp(s, rn), tcg_addr);
+        tcg_gen_mov_i64(cpu_reg_sp(s, rn), dirty_addr);
     }
 }
 
@@ -2836,7 +2851,7 @@ static void disas_ldst_reg_imm9(DisasContext *s, uint32_t insn,
     bool post_index;
     bool writeback;
 
-    TCGv_i64 tcg_addr;
+    TCGv_i64 clean_addr, dirty_addr;
 
     if (is_vector) {
         size |= (opc & 2) << 1;
@@ -2887,17 +2902,18 @@ static void disas_ldst_reg_imm9(DisasContext *s, uint32_t insn,
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
-    tcg_addr = read_cpu_reg_sp(s, rn, 1);
 
+    dirty_addr = read_cpu_reg_sp(s, rn, 1);
     if (!post_index) {
-        tcg_gen_addi_i64(tcg_addr, tcg_addr, imm9);
+        tcg_gen_addi_i64(dirty_addr, dirty_addr, imm9);
     }
+    clean_addr = clean_data_tbi(s, dirty_addr);
 
     if (is_vector) {
         if (is_store) {
-            do_fp_st(s, rt, tcg_addr, size);
+            do_fp_st(s, rt, clean_addr, size);
         } else {
-            do_fp_ld(s, rt, tcg_addr, size);
+            do_fp_ld(s, rt, clean_addr, size);
         }
     } else {
         TCGv_i64 tcg_rt = cpu_reg(s, rt);
@@ -2905,10 +2921,10 @@ static void disas_ldst_reg_imm9(DisasContext *s, uint32_t insn,
         bool iss_sf = disas_ldst_compute_iss_sf(size, is_signed, opc);
 
         if (is_store) {
-            do_gpr_st_memidx(s, tcg_rt, tcg_addr, size, memidx,
+            do_gpr_st_memidx(s, tcg_rt, clean_addr, size, memidx,
                              iss_valid, rt, iss_sf, false);
         } else {
-            do_gpr_ld_memidx(s, tcg_rt, tcg_addr, size,
+            do_gpr_ld_memidx(s, tcg_rt, clean_addr, size,
                              is_signed, is_extended, memidx,
                              iss_valid, rt, iss_sf, false);
         }
@@ -2917,9 +2933,9 @@ static void disas_ldst_reg_imm9(DisasContext *s, uint32_t insn,
     if (writeback) {
         TCGv_i64 tcg_rn = cpu_reg_sp(s, rn);
         if (post_index) {
-            tcg_gen_addi_i64(tcg_addr, tcg_addr, imm9);
+            tcg_gen_addi_i64(dirty_addr, dirty_addr, imm9);
         }
-        tcg_gen_mov_i64(tcg_rn, tcg_addr);
+        tcg_gen_mov_i64(tcg_rn, dirty_addr);
     }
 }
 
@@ -2958,8 +2974,7 @@ static void disas_ldst_reg_roffset(DisasContext *s, uint32_t insn,
     bool is_store = false;
     bool is_extended = false;
 
-    TCGv_i64 tcg_rm;
-    TCGv_i64 tcg_addr;
+    TCGv_i64 tcg_rm, clean_addr, dirty_addr;
 
     if (extract32(opt, 1, 1) == 0) {
         unallocated_encoding(s);
@@ -2993,27 +3008,28 @@ static void disas_ldst_reg_roffset(DisasContext *s, uint32_t insn,
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
-    tcg_addr = read_cpu_reg_sp(s, rn, 1);
+    dirty_addr = read_cpu_reg_sp(s, rn, 1);
 
     tcg_rm = read_cpu_reg(s, rm, 1);
     ext_and_shift_reg(tcg_rm, tcg_rm, opt, shift ? size : 0);
 
-    tcg_gen_add_i64(tcg_addr, tcg_addr, tcg_rm);
+    tcg_gen_add_i64(dirty_addr, dirty_addr, tcg_rm);
+    clean_addr = clean_data_tbi(s, dirty_addr);
 
     if (is_vector) {
         if (is_store) {
-            do_fp_st(s, rt, tcg_addr, size);
+            do_fp_st(s, rt, clean_addr, size);
         } else {
-            do_fp_ld(s, rt, tcg_addr, size);
+            do_fp_ld(s, rt, clean_addr, size);
         }
     } else {
         TCGv_i64 tcg_rt = cpu_reg(s, rt);
         bool iss_sf = disas_ldst_compute_iss_sf(size, is_signed, opc);
         if (is_store) {
-            do_gpr_st(s, tcg_rt, tcg_addr, size,
+            do_gpr_st(s, tcg_rt, clean_addr, size,
                       true, rt, iss_sf, false);
         } else {
-            do_gpr_ld(s, tcg_rt, tcg_addr, size,
+            do_gpr_ld(s, tcg_rt, clean_addr, size,
                       is_signed, is_extended,
                       true, rt, iss_sf, false);
         }
@@ -3047,7 +3063,7 @@ static void disas_ldst_reg_unsigned_imm(DisasContext *s, uint32_t insn,
     unsigned int imm12 = extract32(insn, 10, 12);
     unsigned int offset;
 
-    TCGv_i64 tcg_addr;
+    TCGv_i64 clean_addr, dirty_addr;
 
     bool is_store;
     bool is_signed = false;
@@ -3080,24 +3096,25 @@ static void disas_ldst_reg_unsigned_imm(DisasContext *s, uint32_t insn,
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
-    tcg_addr = read_cpu_reg_sp(s, rn, 1);
+    dirty_addr = read_cpu_reg_sp(s, rn, 1);
     offset = imm12 << size;
-    tcg_gen_addi_i64(tcg_addr, tcg_addr, offset);
+    tcg_gen_addi_i64(dirty_addr, dirty_addr, offset);
+    clean_addr = clean_data_tbi(s, dirty_addr);
 
     if (is_vector) {
         if (is_store) {
-            do_fp_st(s, rt, tcg_addr, size);
+            do_fp_st(s, rt, clean_addr, size);
         } else {
-            do_fp_ld(s, rt, tcg_addr, size);
+            do_fp_ld(s, rt, clean_addr, size);
         }
     } else {
         TCGv_i64 tcg_rt = cpu_reg(s, rt);
         bool iss_sf = disas_ldst_compute_iss_sf(size, is_signed, opc);
         if (is_store) {
-            do_gpr_st(s, tcg_rt, tcg_addr, size,
+            do_gpr_st(s, tcg_rt, clean_addr, size,
                       true, rt, iss_sf, false);
         } else {
-            do_gpr_ld(s, tcg_rt, tcg_addr, size, is_signed, is_extended,
+            do_gpr_ld(s, tcg_rt, clean_addr, size, is_signed, is_extended,
                       true, rt, iss_sf, false);
         }
     }
@@ -3123,7 +3140,7 @@ static void disas_ldst_atomic(DisasContext *s, uint32_t insn,
     int rs = extract32(insn, 16, 5);
     int rn = extract32(insn, 5, 5);
     int o3_opc = extract32(insn, 12, 4);
-    TCGv_i64 tcg_rn, tcg_rs;
+    TCGv_i64 tcg_rs, clean_addr;
     AtomicThreeOpFn *fn;
 
     if (is_vector || !dc_isar_feature(aa64_atomics, s)) {
@@ -3166,7 +3183,7 @@ static void disas_ldst_atomic(DisasContext *s, uint32_t insn,
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
-    tcg_rn = cpu_reg_sp(s, rn);
+    clean_addr = clean_data_tbi(s, cpu_reg_sp(s, rn));
     tcg_rs = read_cpu_reg(s, rs, true);
 
     if (o3_opc == 1) { /* LDCLR */
@@ -3176,7 +3193,7 @@ static void disas_ldst_atomic(DisasContext *s, uint32_t insn,
     /* The tcg atomic primitives are all full barriers.  Therefore we
      * can ignore the Acquire and Release bits of this instruction.
      */
-    fn(cpu_reg(s, rt), tcg_rn, tcg_rs, get_mem_index(s),
+    fn(cpu_reg(s, rt), clean_addr, tcg_rs, get_mem_index(s),
        s->be_data | size | MO_ALIGN);
 }
 
@@ -3201,7 +3218,7 @@ static void disas_ldst_pac(DisasContext *s, uint32_t insn,
     bool is_wback = extract32(insn, 11, 1);
     bool use_key_a = !extract32(insn, 23, 1);
     int offset;
-    TCGv_i64 tcg_addr, tcg_rt;
+    TCGv_i64 clean_addr, dirty_addr, tcg_rt;
 
     if (size != 3 || is_vector || !dc_isar_feature(aa64_pauth, s)) {
         unallocated_encoding(s);
@@ -3211,29 +3228,31 @@ static void disas_ldst_pac(DisasContext *s, uint32_t insn,
     if (rn == 31) {
         gen_check_sp_alignment(s);
     }
-    tcg_addr = read_cpu_reg_sp(s, rn, 1);
+    dirty_addr = read_cpu_reg_sp(s, rn, 1);
 
     if (s->pauth_active) {
         if (use_key_a) {
-            gen_helper_autda(tcg_addr, cpu_env, tcg_addr, cpu_X[31]);
+            gen_helper_autda(dirty_addr, cpu_env, dirty_addr, cpu_X[31]);
         } else {
-            gen_helper_autdb(tcg_addr, cpu_env, tcg_addr, cpu_X[31]);
+            gen_helper_autdb(dirty_addr, cpu_env, dirty_addr, cpu_X[31]);
         }
     }
 
     /* Form the 10-bit signed, scaled offset.  */
     offset = (extract32(insn, 22, 1) << 9) | extract32(insn, 12, 9);
     offset = sextract32(offset << size, 0, 10 + size);
-    tcg_gen_addi_i64(tcg_addr, tcg_addr, offset);
+    tcg_gen_addi_i64(dirty_addr, dirty_addr, offset);
+
+    /* Note that "clean" and "dirty" here refer to TBI not PAC.  */
+    clean_addr = clean_data_tbi(s, dirty_addr);
 
     tcg_rt = cpu_reg(s, rt);
-
-    do_gpr_ld(s, tcg_rt, tcg_addr, size, /* is_signed */ false,
+    do_gpr_ld(s, tcg_rt, clean_addr, size, /* is_signed */ false,
               /* extend */ false, /* iss_valid */ !is_wback,
               /* iss_srt */ rt, /* iss_sf */ true, /* iss_ar */ false);
 
     if (is_wback) {
-        tcg_gen_mov_i64(cpu_reg_sp(s, rn), tcg_addr);
+        tcg_gen_mov_i64(cpu_reg_sp(s, rn), dirty_addr);
     }
 }
 
@@ -3301,7 +3320,7 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
     bool is_store = !extract32(insn, 22, 1);
     bool is_postidx = extract32(insn, 23, 1);
     bool is_q = extract32(insn, 30, 1);
-    TCGv_i64 tcg_addr, tcg_rn, tcg_ebytes;
+    TCGv_i64 clean_addr, tcg_rn, tcg_ebytes;
     TCGMemOp endian = s->be_data;
 
     int ebytes;   /* bytes per element */
@@ -3379,8 +3398,7 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
     elements = (is_q ? 16 : 8) / ebytes;
 
     tcg_rn = cpu_reg_sp(s, rn);
-    tcg_addr = tcg_temp_new_i64();
-    tcg_gen_mov_i64(tcg_addr, tcg_rn);
+    clean_addr = clean_data_tbi(s, tcg_rn);
     tcg_ebytes = tcg_const_i64(ebytes);
 
     for (r = 0; r < rpt; r++) {
@@ -3390,14 +3408,15 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
             for (xs = 0; xs < selem; xs++) {
                 int tt = (rt + r + xs) % 32;
                 if (is_store) {
-                    do_vec_st(s, tt, e, tcg_addr, size, endian);
+                    do_vec_st(s, tt, e, clean_addr, size, endian);
                 } else {
-                    do_vec_ld(s, tt, e, tcg_addr, size, endian);
+                    do_vec_ld(s, tt, e, clean_addr, size, endian);
                 }
-                tcg_gen_add_i64(tcg_addr, tcg_addr, tcg_ebytes);
+                tcg_gen_add_i64(clean_addr, clean_addr, tcg_ebytes);
             }
         }
     }
+    tcg_temp_free_i64(tcg_ebytes);
 
     if (!is_store) {
         /* For non-quad operations, setting a slice of the low
@@ -3416,13 +3435,11 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
     if (is_postidx) {
         int rm = extract32(insn, 16, 5);
         if (rm == 31) {
-            tcg_gen_mov_i64(tcg_rn, tcg_addr);
+            tcg_gen_addi_i64(tcg_rn, tcg_rn, rpt * elements * selem * ebytes);
         } else {
             tcg_gen_add_i64(tcg_rn, tcg_rn, cpu_reg(s, rm));
         }
     }
-    tcg_temp_free_i64(tcg_ebytes);
-    tcg_temp_free_i64(tcg_addr);
 }
 
 /* AdvSIMD load/store single structure
@@ -3464,7 +3481,7 @@ static void disas_ldst_single_struct(DisasContext *s, uint32_t insn)
     bool replicate = false;
     int index = is_q << 3 | S << 2 | size;
     int ebytes, xs;
-    TCGv_i64 tcg_addr, tcg_rn, tcg_ebytes;
+    TCGv_i64 clean_addr, tcg_rn, tcg_ebytes;
 
     switch (scale) {
     case 3:
@@ -3515,8 +3532,7 @@ static void disas_ldst_single_struct(DisasContext *s, uint32_t insn)
     }
 
     tcg_rn = cpu_reg_sp(s, rn);
-    tcg_addr = tcg_temp_new_i64();
-    tcg_gen_mov_i64(tcg_addr, tcg_rn);
+    clean_addr = clean_data_tbi(s, tcg_rn);
     tcg_ebytes = tcg_const_i64(ebytes);
 
     for (xs = 0; xs < selem; xs++) {
@@ -3524,7 +3540,7 @@ static void disas_ldst_single_struct(DisasContext *s, uint32_t insn)
             /* Load and replicate to all elements */
             TCGv_i64 tcg_tmp = tcg_temp_new_i64();
 
-            tcg_gen_qemu_ld_i64(tcg_tmp, tcg_addr,
+            tcg_gen_qemu_ld_i64(tcg_tmp, clean_addr,
                                 get_mem_index(s), s->be_data + scale);
             tcg_gen_gvec_dup_i64(scale, vec_full_reg_offset(s, rt),
                                  (is_q + 1) * 8, vec_full_reg_size(s),
@@ -3533,25 +3549,24 @@ static void disas_ldst_single_struct(DisasContext *s, uint32_t insn)
         } else {
             /* Load/store one element per register */
             if (is_load) {
-                do_vec_ld(s, rt, index, tcg_addr, scale, s->be_data);
+                do_vec_ld(s, rt, index, clean_addr, scale, s->be_data);
             } else {
-                do_vec_st(s, rt, index, tcg_addr, scale, s->be_data);
+                do_vec_st(s, rt, index, clean_addr, scale, s->be_data);
             }
         }
-        tcg_gen_add_i64(tcg_addr, tcg_addr, tcg_ebytes);
+        tcg_gen_add_i64(clean_addr, clean_addr, tcg_ebytes);
         rt = (rt + 1) % 32;
     }
+    tcg_temp_free_i64(tcg_ebytes);
 
     if (is_postidx) {
         int rm = extract32(insn, 16, 5);
         if (rm == 31) {
-            tcg_gen_mov_i64(tcg_rn, tcg_addr);
+            tcg_gen_addi_i64(tcg_rn, tcg_rn, selem * ebytes);
         } else {
             tcg_gen_add_i64(tcg_rn, tcg_rn, cpu_reg(s, rm));
         }
     }
-    tcg_temp_free_i64(tcg_ebytes);
-    tcg_temp_free_i64(tcg_addr);
 }
 
 /* Loads and stores */
-- 
2.17.2

[Qemu-devel] [PATCH 3/4] target/arm: Compute TB_FLAGS for TBI for user-only

[Richard Henderson]

Enables, but does not turn on, TBI for CONFIG_USER_ONLY.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/internals.h | 21 ---------------------
 target/arm/helper.c    | 13 ++++++-------
 2 files changed, 6 insertions(+), 28 deletions(-)

diff --git a/target/arm/internals.h b/target/arm/internals.h
index d01a3f9f44..a4bd1becb7 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -963,30 +963,9 @@ typedef struct ARMVAParameters {
     bool using64k   : 1;
 } ARMVAParameters;
 
-#ifdef CONFIG_USER_ONLY
-static inline ARMVAParameters aa64_va_parameters_both(CPUARMState *env,
-                                                      uint64_t va,
-                                                      ARMMMUIdx mmu_idx)
-{
-    return (ARMVAParameters) {
-        /* 48-bit address space */
-        .tsz = 16,
-        /* We can't handle tagged addresses properly in user-only mode */
-        .tbi = false,
-    };
-}
-
-static inline ARMVAParameters aa64_va_parameters(CPUARMState *env,
-                                                 uint64_t va,
-                                                 ARMMMUIdx mmu_idx, bool data)
-{
-    return aa64_va_parameters_both(env, va, mmu_idx);
-}
-#else
 ARMVAParameters aa64_va_parameters_both(CPUARMState *env, uint64_t va,
                                         ARMMMUIdx mmu_idx);
 ARMVAParameters aa64_va_parameters(CPUARMState *env, uint64_t va,
                                    ARMMMUIdx mmu_idx, bool data);
-#endif
 
 #endif
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 8c28c6d044..0ceb1fa2b8 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6549,7 +6549,7 @@ uint32_t HELPER(rbit)(uint32_t x)
     return revbit32(x);
 }
 
-#if defined(CONFIG_USER_ONLY)
+#ifdef CONFIG_USER_ONLY
 
 /* These should probably raise undefined insn exceptions.  */
 void HELPER(v7m_msr)(CPUARMState *env, uint32_t reg, uint32_t val)
@@ -8923,6 +8923,7 @@ void arm_cpu_do_interrupt(CPUState *cs)
         cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
     }
 }
+#endif /* !CONFIG_USER_ONLY */
 
 /* Return the exception level which controls this address translation regime */
 static inline uint32_t regime_el(CPUARMState *env, ARMMMUIdx mmu_idx)
@@ -9084,6 +9085,7 @@ static inline bool regime_is_user(CPUARMState *env, ARMMMUIdx mmu_idx)
     }
 }
 
+#ifndef CONFIG_USER_ONLY
 /* Translate section/page access permissions to page
  * R/W protection flags
  *
@@ -9771,6 +9773,7 @@ static uint8_t convert_stage2_attrs(CPUARMState *env, uint8_t s2attrs)
 
     return (hiattr << 6) | (hihint << 4) | (loattr << 2) | lohint;
 }
+#endif /* !CONFIG_USER_ONLY */
 
 ARMVAParameters aa64_va_parameters_both(CPUARMState *env, uint64_t va,
                                         ARMMMUIdx mmu_idx)
@@ -9841,6 +9844,7 @@ ARMVAParameters aa64_va_parameters(CPUARMState *env, uint64_t va,
     return ret;
 }
 
+#ifndef CONFIG_USER_ONLY
 static ARMVAParameters aa32_va_parameters(CPUARMState *env, uint32_t va,
                                           ARMMMUIdx mmu_idx)
 {
@@ -13087,11 +13091,7 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
         *pc = env->pc;
         flags = FIELD_DP32(flags, TBFLAG_ANY, AARCH64_STATE, 1);
 
-#ifndef CONFIG_USER_ONLY
-        /*
-         * Get control bits for tagged addresses.  Note that the
-         * translator only uses this for instruction addresses.
-         */
+        /* Get control bits for tagged addresses.  */
         {
             ARMMMUIdx stage1 = stage_1_mmu_idx(mmu_idx);
             ARMVAParameters p0 = aa64_va_parameters_both(env, 0, stage1);
@@ -13110,7 +13110,6 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
             flags = FIELD_DP32(flags, TBFLAG_A64, TBII, tbii);
             flags = FIELD_DP32(flags, TBFLAG_A64, TBID, tbid);
         }
-#endif
 
         if (cpu_isar_feature(aa64_sve, cpu)) {
             int sve_el = sve_exception_el(env, current_el);
-- 
2.17.2

[Qemu-devel] [PATCH 4/4] target/arm: Enable TBI for user-only

[Richard Henderson]

This has been enabled in the linux kernel since v3.11
(commit d50240a5f6cea, 2013-09-03,
"arm64: mm: permit use of tagged pointers at EL0").

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/cpu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 14bc24a35a..5eff6995ee 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -174,6 +174,12 @@ static void arm_cpu_reset(CPUState *s)
         env->vfp.zcr_el[1] = cpu->sve_max_vq - 1;
         env->vfp.zcr_el[2] = env->vfp.zcr_el[1];
         env->vfp.zcr_el[3] = env->vfp.zcr_el[1];
+        /*
+         * Enable TBI0 and TBI1.  While the real kernel only enables TBI0,
+         * turning on both here will produce smaller code and otherwise
+         * make no difference to the user-level emulation.
+         */
+        env->cp15.tcr_el[1].raw_tcr = (3ULL << 37);
 #else
         /* Reset into the highest available EL */
         if (arm_feature(env, ARM_FEATURE_EL3)) {
-- 
2.17.2

Re: [Qemu-devel] [PATCH 1/4] target/arm: Add TBFLAG_A64_TBID, split out gen_top_byte_ignore

[Peter Maydell]

On Thu, 10 Jan 2019 at 12:50, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Split out gen_top_byte_ignore in preparation of handling these
> data accesses; the new tbflags field is not yet honored.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/cpu.h           |  1 +
>  target/arm/translate.h     |  3 ++-
>  target/arm/helper.c        |  1 +
>  target/arm/translate-a64.c | 40 +++++++++++++++++---------------------
>  4 files changed, 22 insertions(+), 23 deletions(-)
>
> diff --git a/target/arm/cpu.h b/target/arm/cpu.h
> index 929f16dd6b..02e6dcce25 100644
> --- a/target/arm/cpu.h
> +++ b/target/arm/cpu.h
> @@ -2996,6 +2996,7 @@ FIELD(TBFLAG_A64, ZCR_LEN, 4, 4)
>  FIELD(TBFLAG_A64, PAUTH_ACTIVE, 8, 1)
>  FIELD(TBFLAG_A64, BT, 9, 1)
>  FIELD(TBFLAG_A64, BTYPE, 10, 2)
> +FIELD(TBFLAG_A64, TBID, 12, 2)
>
>  static inline bool bswap_code(bool sctlr_b)
>  {
> diff --git a/target/arm/translate.h b/target/arm/translate.h
> index f73939d7b4..17748ddfb9 100644
> --- a/target/arm/translate.h
> +++ b/target/arm/translate.h
> @@ -26,7 +26,8 @@ typedef struct DisasContext {
>      int user;
>  #endif
>      ARMMMUIdx mmu_idx; /* MMU index to use for normal loads/stores */
> -    uint8_t tbii;      /* TBI1|TBI0 for EL0/1 or TBI for EL2/3 */
> +    uint8_t tbii;      /* TBI1|TBI0 for insns */
> +    uint8_t tbid;      /* TBI1|TBI0 for data */
>      bool ns;        /* Use non-secure CPREG bank on access */
>      int fp_excp_el; /* FP exception EL or 0 if enabled */
>      int sve_excp_el; /* SVE exception EL or 0 if enabled */
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index 4e9ea2ed39..8c28c6d044 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -13108,6 +13108,7 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
>              }
>
>              flags = FIELD_DP32(flags, TBFLAG_A64, TBII, tbii);
> +            flags = FIELD_DP32(flags, TBFLAG_A64, TBID, tbid);
>          }
>  #endif
>
> diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
> index f225517077..9548252782 100644
> --- a/target/arm/translate-a64.c
> +++ b/target/arm/translate-a64.c
> @@ -284,31 +284,17 @@ void gen_a64_set_pc_im(uint64_t val)
>      tcg_gen_movi_i64(cpu_pc, val);
>  }
>
> -/* Load the PC from a generic TCG variable.
> - *
> - * If address tagging is enabled via the TCR TBI bits, then loading
> - * an address into the PC will clear out any tag in it:
> - *  + for EL2 and EL3 there is only one TBI bit, and if it is set
> - *    then the address is zero-extended, clearing bits [63:56]
> - *  + for EL0 and EL1, TBI0 controls addresses with bit 55 == 0
> - *    and TBI1 controls addressses with bit 55 == 1.
> - *    If the appropriate TBI bit is set for the address then
> - *    the address is sign-extended from bit 55 into bits [63:56]
> - *
> - * We can avoid doing this for relative-branches, because the
> - * PC + offset can never overflow into the tag bits (assuming
> - * that virtual addresses are less than 56 bits wide, as they
> - * are currently), but we must handle it for branch-to-register.
> +/*
> + * Handle Top Byte Ignore (TBI) bits.
> + * We have concatenated tbi{1,0} into tbi.
>   */

This seems to have replaced a usefully explanatory comment
with a very terse one...

> -static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
> +static void gen_top_byte_ignore(DisasContext *s, TCGv_i64 dst,
> +                                TCGv_i64 src, int tbi)
>  {
> -    /* Note that TBII is TBI1:TBI0.  */
> -    int tbi = s->tbii;
> -
>      if (s->current_el <= 1) {
>          if (tbi != 0) {
>              /* Sign-extend from bit 55.  */
> -            tcg_gen_sextract_i64(cpu_pc, src, 0, 56);
> +            tcg_gen_sextract_i64(dst, src, 0, 56);
>
>              if (tbi != 3) {
>                  TCGv_i64 tcg_zero = tcg_const_i64(0);
> @@ -327,13 +313,22 @@ static void gen_a64_set_pc(DisasContext *s, TCGv_i64 src)
>      } else {
>          if (tbi != 0) {
>              /* Force tag byte to all zero */
> -            tcg_gen_extract_i64(cpu_pc, src, 0, 56);
> +            tcg_gen_extract_i64(dst, src, 0, 56);
>              return;
>          }
>      }
>
>      /* Load unmodified address */
> -    tcg_gen_mov_i64(cpu_pc, src);
> +    tcg_gen_mov_i64(dst, src);
> +}

Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM

Re: [Qemu-devel] [PATCH 2/4] target/arm: Clean TBI for data operations in the translator

[Peter Maydell]

On Thu, 10 Jan 2019 at 12:50, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> This will allow TBI to be used in user-only mode, as well as
> avoid ping-ponging the softmmu TLB when TBI is in use.  It
> will also enable other armv8 extensions.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM

Re: [Qemu-devel] [PATCH 3/4] target/arm: Compute TB_FLAGS for TBI for user-only

[Peter Maydell]

On Thu, 10 Jan 2019 at 12:50, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Enables, but does not turn on, TBI for CONFIG_USER_ONLY.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/internals.h | 21 ---------------------
>  target/arm/helper.c    | 13 ++++++-------
>  2 files changed, 6 insertions(+), 28 deletions(-)

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM

Re: [Qemu-devel] [PATCH 4/4] target/arm: Enable TBI for user-only

[Peter Maydell]

On Thu, 10 Jan 2019 at 12:50, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> This has been enabled in the linux kernel since v3.11
> (commit d50240a5f6cea, 2013-09-03,
> "arm64: mm: permit use of tagged pointers at EL0").
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/cpu.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/target/arm/cpu.c b/target/arm/cpu.c
> index 14bc24a35a..5eff6995ee 100644
> --- a/target/arm/cpu.c
> +++ b/target/arm/cpu.c
> @@ -174,6 +174,12 @@ static void arm_cpu_reset(CPUState *s)
>          env->vfp.zcr_el[1] = cpu->sve_max_vq - 1;
>          env->vfp.zcr_el[2] = env->vfp.zcr_el[1];
>          env->vfp.zcr_el[3] = env->vfp.zcr_el[1];
> +        /*
> +         * Enable TBI0 and TBI1.  While the real kernel only enables TBI0,
> +         * turning on both here will produce smaller code and otherwise
> +         * make no difference to the user-level emulation.
> +         */
> +        env->cp15.tcr_el[1].raw_tcr = (3ULL << 37);
>  #else
>          /* Reset into the highest available EL */
>          if (arm_feature(env, ARM_FEATURE_EL3)) {
> --
> 2.17.2

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM