[PATCH 4.9 00/43] 4.9.310-rc1 review

[PATCH 4.9 00/43] 4.9.310-rc1 review

[Greg Kroah-Hartman]

This is the start of the stable review cycle for the 4.9.310 release.
There are 43 patches in this series, all will be posted as a response
to this one.  If anyone has any issues with these being applied, please
let me know.

Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
Anything received after that time might be too late.

The whole patch series can be found in one patch at:
	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.310-rc1.gz
or in the git tree and branch at:
	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Linux 4.9.310-rc1

James Morse <james.morse@arm.com>
    arm64: Use the clearbhb instruction in mitigations

James Morse <james.morse@arm.com>
    arm64: add ID_AA64ISAR2_EL1 sys register

James Morse <james.morse@arm.com>
    KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated

James Morse <james.morse@arm.com>
    arm64: Mitigate spectre style branch history side channels

James Morse <james.morse@arm.com>
    KVM: arm64: Add templates for BHB mitigation sequences

James Morse <james.morse@arm.com>
    arm64: Add percpu vectors for EL1

James Morse <james.morse@arm.com>
    arm64: entry: Add macro for reading symbol addresses from the trampoline

James Morse <james.morse@arm.com>
    arm64: entry: Add vectors that have the bhb mitigation sequences

James Morse <james.morse@arm.com>
    arm64: Move arm64_update_smccc_conduit() out of SSBD ifdef

James Morse <james.morse@arm.com>
    arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations

James Morse <james.morse@arm.com>
    arm64: entry: Allow the trampoline text to occupy multiple pages

James Morse <james.morse@arm.com>
    arm64: entry: Make the kpti trampoline's kpti sequence optional

James Morse <james.morse@arm.com>
    arm64: entry: Move trampoline macros out of ifdef'd section

James Morse <james.morse@arm.com>
    arm64: entry: Don't assume tramp_vectors is the start of the vectors

James Morse <james.morse@arm.com>
    arm64: entry: Allow tramp_alias to access symbols after the 4K boundary

James Morse <james.morse@arm.com>
    arm64: entry: Move the trampoline data page before the text page

James Morse <james.morse@arm.com>
    arm64: entry: Free up another register on kpti's tramp_exit path

James Morse <james.morse@arm.com>
    arm64: entry: Make the trampoline cleanup optional

James Morse <james.morse@arm.com>
    arm64: entry.S: Add ventry overflow sanity checks

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: Add helper to decode register from instruction

Anshuman Khandual <anshuman.khandual@arm.com>
    arm64: Add Cortex-X2 CPU part definition

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: Add Neoverse-N2, Cortex-A710 CPU part definition

Rob Herring <robh@kernel.org>
    arm64: Add part number for Arm Cortex-A77

Marc Zyngier <marc.zyngier@arm.com>
    arm64: Add part number for Neoverse N1

Marc Zyngier <marc.zyngier@arm.com>
    arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT

Marc Zyngier <marc.zyngier@arm.com>
    arm64: Add silicon-errata.txt entry for ARM erratum 1188873

Arnd Bergmann <arnd@arndb.de>
    arm64: arch_timer: avoid unused function warning

Marc Zyngier <marc.zyngier@arm.com>
    arm64: arch_timer: Add workaround for ARM erratum 1188873

Marc Zyngier <marc.zyngier@arm.com>
    arm64: arch_timer: Add erratum handler for CPU-specific capability

Marc Zyngier <marc.zyngier@arm.com>
    arm64: arch_timer: Add infrastructure for multiple erratum detection methods

Ding Tianhong <dingtianhong@huawei.com>
    clocksource/drivers/arm_arch_timer: Introduce generic errata handling infrastructure

Ding Tianhong <dingtianhong@huawei.com>
    clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameter

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: capabilities: Add support for checks based on a list of MIDRs

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: Add helpers for checking CPU MIDR against a range

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: capabilities: Clean up midr range helpers

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: capabilities: Add flags to handle the conflicts on late CPU

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: capabilities: Prepare for fine grained capabilities

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: capabilities: Move errata processing code

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: capabilities: Move errata work around check on boot CPU

Dave Martin <dave.martin@arm.com>
    arm64: capabilities: Update prototype for enable call back

Suzuki K Poulose <suzuki.poulose@arm.com>
    arm64: Add MIDR encoding for Arm Cortex-A55 and Cortex-A35

James Morse <james.morse@arm.com>
    arm64: Remove useless UAO IPI and describe how this gets enabled

Robert Richter <rrichter@cavium.com>
    arm64: errata: Provide macro for major and minor cpu revisions


-------------

Diffstat:

 Documentation/arm64/silicon-errata.txt |   1 +
 Documentation/kernel-parameters.txt    |   9 -
 Makefile                               |   4 +-
 arch/arm/include/asm/kvm_host.h        |   5 +
 arch/arm/kvm/psci.c                    |   4 +
 arch/arm64/Kconfig                     |  24 ++
 arch/arm64/include/asm/arch_timer.h    |  44 ++-
 arch/arm64/include/asm/assembler.h     |  34 ++
 arch/arm64/include/asm/cpu.h           |   1 +
 arch/arm64/include/asm/cpucaps.h       |   4 +-
 arch/arm64/include/asm/cpufeature.h    | 232 ++++++++++++-
 arch/arm64/include/asm/cputype.h       |  63 ++++
 arch/arm64/include/asm/fixmap.h        |   6 +-
 arch/arm64/include/asm/insn.h          |   2 +
 arch/arm64/include/asm/kvm_host.h      |   4 +
 arch/arm64/include/asm/kvm_mmu.h       |   2 +-
 arch/arm64/include/asm/mmu.h           |   8 +-
 arch/arm64/include/asm/processor.h     |   6 +-
 arch/arm64/include/asm/sections.h      |   6 +
 arch/arm64/include/asm/sysreg.h        |   5 +
 arch/arm64/include/asm/vectors.h       |  74 +++++
 arch/arm64/kernel/bpi.S                |  55 +++
 arch/arm64/kernel/cpu_errata.c         | 591 ++++++++++++++++++++++++++-------
 arch/arm64/kernel/cpufeature.c         | 167 +++++++---
 arch/arm64/kernel/cpuinfo.c            |   1 +
 arch/arm64/kernel/entry.S              | 197 ++++++++---
 arch/arm64/kernel/fpsimd.c             |   1 +
 arch/arm64/kernel/insn.c               |  29 ++
 arch/arm64/kernel/smp.c                |   6 -
 arch/arm64/kernel/traps.c              |   4 +-
 arch/arm64/kernel/vmlinux.lds.S        |   2 +-
 arch/arm64/kvm/hyp/hyp-entry.S         |   4 +
 arch/arm64/kvm/hyp/switch.c            |   9 +-
 arch/arm64/mm/fault.c                  |  17 +-
 arch/arm64/mm/mmu.c                    |  11 +-
 drivers/clocksource/Kconfig            |   4 +
 drivers/clocksource/arm_arch_timer.c   | 192 ++++++++---
 include/linux/arm-smccc.h              |   7 +
 38 files changed, 1504 insertions(+), 331 deletions(-)

[PATCH 4.9 01/43] arm64: errata: Provide macro for major and minor cpu revisions

[Greg Kroah-Hartman]

From: Robert Richter <rrichter@cavium.com>

commit fa5ce3d1928c441c3d241c34a00c07c8f5880b1a upstream

Definition of cpu ranges are hard to read if the cpu variant is not
zero. Provide MIDR_CPU_VAR_REV() macro to describe the full hardware
revision of a cpu including variant and (minor) revision.

Signed-off-by: Robert Richter <rrichter@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
[ morse: some parts of this patch were already backported as part of
  b8c320884eff003581ee61c5970a2e83f513eff1 ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/cpu_errata.c |   15 +++++++++------
 arch/arm64/kernel/cpufeature.c |    8 +++-----
 2 files changed, 12 insertions(+), 11 deletions(-)

--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -408,8 +408,9 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A57 r0p0 - r1p2 */
 		.desc = "ARM erratum 832075",
 		.capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE,
-		MIDR_RANGE(MIDR_CORTEX_A57, 0x00,
-			   (1 << MIDR_VARIANT_SHIFT) | 2),
+		MIDR_RANGE(MIDR_CORTEX_A57,
+			   MIDR_CPU_VAR_REV(0, 0),
+			   MIDR_CPU_VAR_REV(1, 2)),
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_834220
@@ -417,8 +418,9 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A57 r0p0 - r1p2 */
 		.desc = "ARM erratum 834220",
 		.capability = ARM64_WORKAROUND_834220,
-		MIDR_RANGE(MIDR_CORTEX_A57, 0x00,
-			   (1 << MIDR_VARIANT_SHIFT) | 2),
+		MIDR_RANGE(MIDR_CORTEX_A57,
+			   MIDR_CPU_VAR_REV(0, 0),
+			   MIDR_CPU_VAR_REV(1, 2)),
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_845719
@@ -442,8 +444,9 @@ const struct arm64_cpu_capabilities arm6
 	/* Cavium ThunderX, T88 pass 1.x - 2.1 */
 		.desc = "Cavium erratum 27456",
 		.capability = ARM64_WORKAROUND_CAVIUM_27456,
-		MIDR_RANGE(MIDR_THUNDERX, 0x00,
-			   (1 << MIDR_VARIANT_SHIFT) | 1),
+		MIDR_RANGE(MIDR_THUNDERX,
+			   MIDR_CPU_VAR_REV(0, 0),
+			   MIDR_CPU_VAR_REV(1, 1)),
 	},
 	{
 	/* Cavium ThunderX, T81 pass 1.0 */
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -728,13 +728,11 @@ static bool has_useable_gicv3_cpuif(cons
 static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused)
 {
 	u32 midr = read_cpuid_id();
-	u32 rv_min, rv_max;
 
 	/* Cavium ThunderX pass 1.x and 2.x */
-	rv_min = 0;
-	rv_max = (1 << MIDR_VARIANT_SHIFT) | MIDR_REVISION_MASK;
-
-	return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, rv_min, rv_max);
+	return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX,
+		MIDR_CPU_VAR_REV(0, 0),
+		MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK));
 }
 
 static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused)

[PATCH 4.9 02/43] arm64: Remove useless UAO IPI and describe how this gets enabled

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit c8b06e3fddddaae1a87ed479edcb8b3d85caecc7 upstream.

Since its introduction, the UAO enable call was broken, and useless.
commit 2a6dcb2b5f3e ("arm64: cpufeature: Schedule enable() calls instead
of calling them via IPI"), fixed the framework so that these calls
are scheduled, so that they can modify PSTATE.

Now it is just useless. Remove it. UAO is enabled by the code patching
which causes get_user() and friends to use the 'ldtr' family of
instructions. This relies on the PSTATE.UAO bit being set to match
addr_limit, which we do in uao_thread_switch() called via __switch_to().

All that is needed to enable UAO is patch the code, and call schedule().
__apply_alternatives_multi_stop() calls stop_machine() when it modifies
the kernel text to enable the alternatives, (including the UAO code in
uao_thread_switch()). Once stop_machine() has finished __switch_to() is
called to reschedule the original task, this causes PSTATE.UAO to be set
appropriately. An explicit enable() call is not needed.

Reported-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/processor.h |    1 -
 arch/arm64/kernel/cpufeature.c     |    5 ++++-
 arch/arm64/mm/fault.c              |   14 --------------
 3 files changed, 4 insertions(+), 16 deletions(-)

--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -220,7 +220,6 @@ static inline void spin_lock_prefetch(co
 #endif
 
 int cpu_enable_pan(void *__unused);
-int cpu_enable_uao(void *__unused);
 int cpu_enable_cache_maint_trap(void *__unused);
 
 #endif /* __ASSEMBLY__ */
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -905,7 +905,10 @@ static const struct arm64_cpu_capabiliti
 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
 		.min_field_value = 1,
-		.enable = cpu_enable_uao,
+		/*
+		 * We rely on stop_machine() calling uao_thread_switch() to set
+		 * UAO immediately after patching.
+		 */
 	},
 #endif /* CONFIG_ARM64_UAO */
 #ifdef CONFIG_ARM64_PAN
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -740,17 +740,3 @@ int cpu_enable_pan(void *__unused)
 	return 0;
 }
 #endif /* CONFIG_ARM64_PAN */
-
-#ifdef CONFIG_ARM64_UAO
-/*
- * Kernel threads have fs=KERNEL_DS by default, and don't need to call
- * set_fs(), devtmpfs in particular relies on this behaviour.
- * We need to enable the feature at runtime (instead of adding it to
- * PSR_MODE_EL1h) as the feature may not be implemented by the cpu.
- */
-int cpu_enable_uao(void *__unused)
-{
-	asm(SET_PSTATE_UAO(1));
-	return 0;
-}
-#endif /* CONFIG_ARM64_UAO */

[PATCH 4.9 03/43] arm64: Add MIDR encoding for Arm Cortex-A55 and Cortex-A35

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

commit 6e616864f21160d8d503523b60a53a29cecc6f24 upstream.

Update the MIDR encodings for the Cortex-A55 and Cortex-A35

Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cputype.h |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -83,6 +83,8 @@
 #define ARM_CPU_PART_CORTEX_A53		0xD03
 #define ARM_CPU_PART_CORTEX_A73		0xD09
 #define ARM_CPU_PART_CORTEX_A75		0xD0A
+#define ARM_CPU_PART_CORTEX_A35		0xD04
+#define ARM_CPU_PART_CORTEX_A55		0xD05
 
 #define APM_CPU_PART_POTENZA		0x000
 
@@ -98,6 +100,8 @@
 #define MIDR_CORTEX_A72 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A72)
 #define MIDR_CORTEX_A73 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A73)
 #define MIDR_CORTEX_A75 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A75)
+#define MIDR_CORTEX_A35 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A35)
+#define MIDR_CORTEX_A55 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A55)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
 #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2)

[PATCH 4.9 04/43] arm64: capabilities: Update prototype for enable call back

[Greg Kroah-Hartman]

From: Dave Martin <dave.martin@arm.com>

[ Upstream commit c0cda3b8ee6b4b6851b2fd8b6db91fd7b0e2524a ]

We issue the enable() call back for all CPU hwcaps capabilities
available on the system, on all the CPUs. So far we have ignored
the argument passed to the call back, which had a prototype to
accept a "void *" for use with on_each_cpu() and later with
stop_machine(). However, with commit 0a0d111d40fd1
("arm64: cpufeature: Pass capability structure to ->enable callback"),
there are some users of the argument who wants the matching capability
struct pointer where there are multiple matching criteria for a single
capability. Clean up the declaration of the call back to make it clear.

 1) Renamed to cpu_enable(), to imply taking necessary actions on the
    called CPU for the entry.
 2) Pass const pointer to the capability, to allow the call back to
    check the entry. (e.,g to check if any action is needed on the CPU)
 3) We don't care about the result of the call back, turning this to
    a void.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: James Morse <james.morse@arm.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Dave Martin <dave.martin@arm.com>
[suzuki: convert more users, rename call back and drop results]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpufeature.h |    7 ++++-
 arch/arm64/include/asm/processor.h  |    5 ++--
 arch/arm64/kernel/cpu_errata.c      |   44 ++++++++++++++++++------------------
 arch/arm64/kernel/cpufeature.c      |   34 +++++++++++++++++----------
 arch/arm64/kernel/fpsimd.c          |    1 
 arch/arm64/kernel/traps.c           |    4 +--
 arch/arm64/mm/fault.c               |    3 --
 7 files changed, 56 insertions(+), 42 deletions(-)

--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -77,7 +77,12 @@ struct arm64_cpu_capabilities {
 	u16 capability;
 	int def_scope;			/* default scope */
 	bool (*matches)(const struct arm64_cpu_capabilities *caps, int scope);
-	int (*enable)(void *);		/* Called on all active CPUs */
+	/*
+	 * Take the appropriate actions to enable this capability for this CPU.
+	 * For each successfully booted CPU, this method is called for each
+	 * globally detected capability.
+	 */
+	void (*cpu_enable)(const struct arm64_cpu_capabilities *cap);
 	union {
 		struct {	/* To be used for erratum handling only */
 			u32 midr_model;
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -37,6 +37,7 @@
 #include <linux/string.h>
 
 #include <asm/alternative.h>
+#include <asm/cpufeature.h>
 #include <asm/fpsimd.h>
 #include <asm/hw_breakpoint.h>
 #include <asm/lse.h>
@@ -219,8 +220,8 @@ static inline void spin_lock_prefetch(co
 
 #endif
 
-int cpu_enable_pan(void *__unused);
-int cpu_enable_cache_maint_trap(void *__unused);
+void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused);
+void cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused);
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_PROCESSOR_H */
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -48,11 +48,11 @@ has_mismatched_cache_type(const struct a
 	       (arm64_ftr_reg_ctrel0.sys_val & mask);
 }
 
-static int cpu_enable_trap_ctr_access(void *__unused)
+static void
+cpu_enable_trap_ctr_access(const struct arm64_cpu_capabilities *__unused)
 {
 	/* Clear SCTLR_EL1.UCT */
 	config_sctlr_el1(SCTLR_EL1_UCT, 0);
-	return 0;
 }
 
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
@@ -152,25 +152,25 @@ static void call_hvc_arch_workaround_1(v
 	arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
 }
 
-static int enable_smccc_arch_workaround_1(void *data)
+static void
+enable_smccc_arch_workaround_1(const struct arm64_cpu_capabilities *entry)
 {
-	const struct arm64_cpu_capabilities *entry = data;
 	bp_hardening_cb_t cb;
 	void *smccc_start, *smccc_end;
 	struct arm_smccc_res res;
 
 	if (!entry->matches(entry, SCOPE_LOCAL_CPU))
-		return 0;
+		return;
 
 	if (psci_ops.smccc_version == SMCCC_VERSION_1_0)
-		return 0;
+		return;
 
 	switch (psci_ops.conduit) {
 	case PSCI_CONDUIT_HVC:
 		arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
 				  ARM_SMCCC_ARCH_WORKAROUND_1, &res);
 		if ((int)res.a0 < 0)
-			return 0;
+			return;
 		cb = call_hvc_arch_workaround_1;
 		smccc_start = __smccc_workaround_1_hvc_start;
 		smccc_end = __smccc_workaround_1_hvc_end;
@@ -180,19 +180,19 @@ static int enable_smccc_arch_workaround_
 		arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
 				  ARM_SMCCC_ARCH_WORKAROUND_1, &res);
 		if ((int)res.a0 < 0)
-			return 0;
+			return;
 		cb = call_smc_arch_workaround_1;
 		smccc_start = __smccc_workaround_1_smc_start;
 		smccc_end = __smccc_workaround_1_smc_end;
 		break;
 
 	default:
-		return 0;
+		return;
 	}
 
 	install_bp_hardening_cb(entry, cb, smccc_start, smccc_end);
 
-	return 0;
+	return;
 }
 #endif	/* CONFIG_HARDEN_BRANCH_PREDICTOR */
 
@@ -391,7 +391,7 @@ const struct arm64_cpu_capabilities arm6
 		.desc = "ARM errata 826319, 827319, 824069",
 		.capability = ARM64_WORKAROUND_CLEAN_CACHE,
 		MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x02),
-		.enable = cpu_enable_cache_maint_trap,
+		.cpu_enable = cpu_enable_cache_maint_trap,
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_819472
@@ -400,7 +400,7 @@ const struct arm64_cpu_capabilities arm6
 		.desc = "ARM errata 819472",
 		.capability = ARM64_WORKAROUND_CLEAN_CACHE,
 		MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x01),
-		.enable = cpu_enable_cache_maint_trap,
+		.cpu_enable = cpu_enable_cache_maint_trap,
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_832075
@@ -460,45 +460,45 @@ const struct arm64_cpu_capabilities arm6
 		.capability = ARM64_MISMATCHED_CACHE_LINE_SIZE,
 		.matches = has_mismatched_cache_type,
 		.def_scope = SCOPE_LOCAL_CPU,
-		.enable = cpu_enable_trap_ctr_access,
+		.cpu_enable = cpu_enable_trap_ctr_access,
 	},
 	{
 		.desc = "Mismatched cache type",
 		.capability = ARM64_MISMATCHED_CACHE_TYPE,
 		.matches = has_mismatched_cache_type,
 		.def_scope = SCOPE_LOCAL_CPU,
-		.enable = cpu_enable_trap_ctr_access,
+		.cpu_enable = cpu_enable_trap_ctr_access,
 	},
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
-		.enable = enable_smccc_arch_workaround_1,
+		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
-		.enable = enable_smccc_arch_workaround_1,
+		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
-		.enable = enable_smccc_arch_workaround_1,
+		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
 		MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
-		.enable = enable_smccc_arch_workaround_1,
+		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
 		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
-		.enable = enable_smccc_arch_workaround_1,
+		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
 		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
-		.enable = enable_smccc_arch_workaround_1,
+		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 #endif
 #ifdef CONFIG_ARM64_SSBD
@@ -524,8 +524,8 @@ void verify_local_cpu_errata_workarounds
 
 	for (; caps->matches; caps++) {
 		if (cpus_have_cap(caps->capability)) {
-			if (caps->enable)
-				caps->enable((void *)caps);
+			if (caps->cpu_enable)
+				caps->cpu_enable(caps);
 		} else if (caps->matches(caps, SCOPE_LOCAL_CPU)) {
 			pr_crit("CPU%d: Requires work around for %s, not detected"
 					" at boot time\n",
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -800,7 +800,8 @@ static bool unmap_kernel_at_el0(const st
 						     ID_AA64PFR0_CSV3_SHIFT);
 }
 
-static int kpti_install_ng_mappings(void *__unused)
+static void
+kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
 {
 	typedef void (kpti_remap_fn)(int, int, phys_addr_t);
 	extern kpti_remap_fn idmap_kpti_install_ng_mappings;
@@ -810,7 +811,7 @@ static int kpti_install_ng_mappings(void
 	int cpu = smp_processor_id();
 
 	if (kpti_applied)
-		return 0;
+		return;
 
 	remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings);
 
@@ -821,7 +822,7 @@ static int kpti_install_ng_mappings(void
 	if (!cpu)
 		kpti_applied = true;
 
-	return 0;
+	return;
 }
 
 static int __init parse_kpti(char *str)
@@ -838,7 +839,7 @@ static int __init parse_kpti(char *str)
 early_param("kpti", parse_kpti);
 #endif	/* CONFIG_UNMAP_KERNEL_AT_EL0 */
 
-static int cpu_copy_el2regs(void *__unused)
+static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
 {
 	/*
 	 * Copy register values that aren't redirected by hardware.
@@ -850,8 +851,6 @@ static int cpu_copy_el2regs(void *__unus
 	 */
 	if (!alternatives_applied)
 		write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
-
-	return 0;
 }
 
 static const struct arm64_cpu_capabilities arm64_features[] = {
@@ -875,7 +874,7 @@ static const struct arm64_cpu_capabiliti
 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
 		.sign = FTR_UNSIGNED,
 		.min_field_value = 1,
-		.enable = cpu_enable_pan,
+		.cpu_enable = cpu_enable_pan,
 	},
 #endif /* CONFIG_ARM64_PAN */
 #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS)
@@ -923,7 +922,7 @@ static const struct arm64_cpu_capabiliti
 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
 		.def_scope = SCOPE_SYSTEM,
 		.matches = runs_at_el2,
-		.enable = cpu_copy_el2regs,
+		.cpu_enable = cpu_copy_el2regs,
 	},
 	{
 		.desc = "32-bit EL0 Support",
@@ -947,7 +946,7 @@ static const struct arm64_cpu_capabiliti
 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
 		.def_scope = SCOPE_SYSTEM,
 		.matches = unmap_kernel_at_el0,
-		.enable = kpti_install_ng_mappings,
+		.cpu_enable = kpti_install_ng_mappings,
 	},
 #endif
 	{},
@@ -1075,6 +1074,14 @@ void update_cpu_capabilities(const struc
 	}
 }
 
+static int __enable_cpu_capability(void *arg)
+{
+	const struct arm64_cpu_capabilities *cap = arg;
+
+	cap->cpu_enable(cap);
+	return 0;
+}
+
 /*
  * Run through the enabled capabilities and enable() it on all active
  * CPUs
@@ -1090,14 +1097,15 @@ void __init enable_cpu_capabilities(cons
 		/* Ensure cpus_have_const_cap(num) works */
 		static_branch_enable(&cpu_hwcap_keys[num]);
 
-		if (caps->enable) {
+		if (caps->cpu_enable) {
 			/*
 			 * Use stop_machine() as it schedules the work allowing
 			 * us to modify PSTATE, instead of on_each_cpu() which
 			 * uses an IPI, giving us a PSTATE that disappears when
 			 * we return.
 			 */
-			stop_machine(caps->enable, (void *)caps, cpu_online_mask);
+			stop_machine(__enable_cpu_capability, (void *)caps,
+				     cpu_online_mask);
 		}
 	}
 }
@@ -1155,8 +1163,8 @@ verify_local_cpu_features(const struct a
 					smp_processor_id(), caps->desc);
 			cpu_die_early();
 		}
-		if (caps->enable)
-			caps->enable((void *)caps);
+		if (caps->cpu_enable)
+			caps->cpu_enable(caps);
 	}
 }
 
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -26,6 +26,7 @@
 #include <linux/hardirq.h>
 
 #include <asm/fpsimd.h>
+#include <asm/cpufeature.h>
 #include <asm/cputype.h>
 
 #define FPEXC_IOF	(1 << 0)
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -34,6 +34,7 @@
 
 #include <asm/atomic.h>
 #include <asm/bug.h>
+#include <asm/cpufeature.h>
 #include <asm/debug-monitors.h>
 #include <asm/esr.h>
 #include <asm/insn.h>
@@ -432,10 +433,9 @@ asmlinkage void __exception do_undefinst
 	force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0);
 }
 
-int cpu_enable_cache_maint_trap(void *__unused)
+void cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused)
 {
 	config_sctlr_el1(SCTLR_EL1_UCI, 0);
-	return 0;
 }
 
 #define __user_cache_maint(insn, address, res)			\
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -727,7 +727,7 @@ asmlinkage int __exception do_debug_exce
 NOKPROBE_SYMBOL(do_debug_exception);
 
 #ifdef CONFIG_ARM64_PAN
-int cpu_enable_pan(void *__unused)
+void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
 {
 	/*
 	 * We modify PSTATE. This won't work from irq context as the PSTATE
@@ -737,6 +737,5 @@ int cpu_enable_pan(void *__unused)
 
 	config_sctlr_el1(SCTLR_EL1_SPAN, 0);
 	asm(SET_PSTATE_PAN(1));
-	return 0;
 }
 #endif /* CONFIG_ARM64_PAN */

[PATCH 4.9 05/43] arm64: capabilities: Move errata work around check on boot CPU

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit 5e91107b06811f0ca147cebbedce53626c9c4443 ]

We trigger CPU errata work around check on the boot CPU from
smp_prepare_boot_cpu() to make sure that we run the checks only
after the CPU feature infrastructure is initialised. While this
is correct, we can also do this from init_cpu_features() which
initilises the infrastructure, and is called only on the
Boot CPU. This helps to consolidate the CPU capability handling
to cpufeature.c. No functional changes.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/cpufeature.c |    5 +++++
 arch/arm64/kernel/smp.c        |    6 ------
 2 files changed, 5 insertions(+), 6 deletions(-)

--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -476,6 +476,11 @@ void __init init_cpu_features(struct cpu
 		init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
 	}
 
+	/*
+	 * Run the errata work around checks on the boot CPU, once we have
+	 * initialised the cpu feature infrastructure.
+	 */
+	update_cpu_errata_workarounds();
 }
 
 static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -444,12 +444,6 @@ void __init smp_prepare_boot_cpu(void)
 	jump_label_init();
 	cpuinfo_store_boot_cpu();
 	save_boot_cpu_run_el();
-	/*
-	 * Run the errata work around checks on the boot CPU, once we have
-	 * initialised the cpu feature infrastructure from
-	 * cpuinfo_store_boot_cpu() above.
-	 */
-	update_cpu_errata_workarounds();
 }
 
 static u64 __init of_get_cpu_mpidr(struct device_node *dn)

[PATCH 4.9 06/43] arm64: capabilities: Move errata processing code

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit 1e89baed5d50d2b8d9fd420830902570270703f1 ]

We have errata work around processing code in cpu_errata.c,
which calls back into helpers defined in cpufeature.c. Now
that we are going to make the handling of capabilities
generic, by adding the information to each capability,
move the errata work around specific processing code.
No functional changes.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpufeature.h |    7 -----
 arch/arm64/kernel/cpu_errata.c      |   33 ---------------------------
 arch/arm64/kernel/cpufeature.c      |   43 +++++++++++++++++++++++++++++++++---
 3 files changed, 40 insertions(+), 43 deletions(-)

--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -200,15 +200,8 @@ static inline bool id_aa64pfr0_32bit_el0
 }
 
 void __init setup_cpu_features(void);
-
-void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
-			    const char *info);
-void enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps);
 void check_local_cpu_capabilities(void);
 
-void update_cpu_errata_workarounds(void);
-void __init enable_errata_workarounds(void);
-void verify_local_cpu_errata_workarounds(void);
 
 u64 read_system_reg(u32 id);
 
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -512,36 +512,3 @@ const struct arm64_cpu_capabilities arm6
 	{
 	}
 };
-
-/*
- * The CPU Errata work arounds are detected and applied at boot time
- * and the related information is freed soon after. If the new CPU requires
- * an errata not detected at boot, fail this CPU.
- */
-void verify_local_cpu_errata_workarounds(void)
-{
-	const struct arm64_cpu_capabilities *caps = arm64_errata;
-
-	for (; caps->matches; caps++) {
-		if (cpus_have_cap(caps->capability)) {
-			if (caps->cpu_enable)
-				caps->cpu_enable(caps);
-		} else if (caps->matches(caps, SCOPE_LOCAL_CPU)) {
-			pr_crit("CPU%d: Requires work around for %s, not detected"
-					" at boot time\n",
-				smp_processor_id(),
-				caps->desc ? : "an erratum");
-			cpu_die_early();
-		}
-	}
-}
-
-void update_cpu_errata_workarounds(void)
-{
-	update_cpu_capabilities(arm64_errata, "enabling workaround for");
-}
-
-void __init enable_errata_workarounds(void)
-{
-	enable_cpu_capabilities(arm64_errata);
-}
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -439,6 +439,9 @@ static void __init init_cpu_ftr_reg(u32
 	reg->strict_mask = strict_mask;
 }
 
+extern const struct arm64_cpu_capabilities arm64_errata[];
+static void update_cpu_errata_workarounds(void);
+
 void __init init_cpu_features(struct cpuinfo_arm64 *info)
 {
 	/* Before we start using the tables, make sure it is sorted */
@@ -1066,8 +1069,8 @@ static bool __this_cpu_has_cap(const str
 	return false;
 }
 
-void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
-			    const char *info)
+static void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
+				    const char *info)
 {
 	for (; caps->matches; caps++) {
 		if (!caps->matches(caps, caps->def_scope))
@@ -1091,7 +1094,8 @@ static int __enable_cpu_capability(void
  * Run through the enabled capabilities and enable() it on all active
  * CPUs
  */
-void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
+static void __init
+enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
 {
 	for (; caps->matches; caps++) {
 		unsigned int num = caps->capability;
@@ -1174,6 +1178,39 @@ verify_local_cpu_features(const struct a
 }
 
 /*
+ * The CPU Errata work arounds are detected and applied at boot time
+ * and the related information is freed soon after. If the new CPU requires
+ * an errata not detected at boot, fail this CPU.
+ */
+static void verify_local_cpu_errata_workarounds(void)
+{
+	const struct arm64_cpu_capabilities *caps = arm64_errata;
+
+	for (; caps->matches; caps++) {
+		if (cpus_have_cap(caps->capability)) {
+			if (caps->cpu_enable)
+				caps->cpu_enable(caps);
+		} else if (caps->matches(caps, SCOPE_LOCAL_CPU)) {
+			pr_crit("CPU%d: Requires work around for %s, not detected"
+					" at boot time\n",
+				smp_processor_id(),
+				caps->desc ? : "an erratum");
+			cpu_die_early();
+		}
+	}
+}
+
+static void update_cpu_errata_workarounds(void)
+{
+	update_cpu_capabilities(arm64_errata, "enabling workaround for");
+}
+
+static void __init enable_errata_workarounds(void)
+{
+	enable_cpu_capabilities(arm64_errata);
+}
+
+/*
  * Run through the enabled system capabilities and enable() it on this CPU.
  * The capabilities were decided based on the available CPUs at the boot time.
  * Any new CPU should match the system wide status of the capability. If the

[PATCH 4.9 07/43] arm64: capabilities: Prepare for fine grained capabilities

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit 143ba05d867af34827faf99e0eed4de27106c7cb ]

We use arm64_cpu_capabilities to represent CPU ELF HWCAPs exposed
to the userspace and the CPU hwcaps used by the kernel, which
include cpu features and CPU errata work arounds. Capabilities
have some properties that decide how they should be treated :

 1) Detection, i.e scope : A cap could be "detected" either :
    - if it is present on at least one CPU (SCOPE_LOCAL_CPU)
	Or
    - if it is present on all the CPUs (SCOPE_SYSTEM)

 2) When is it enabled ? - A cap is treated as "enabled" when the
  system takes some action based on whether the capability is detected or
  not. e.g, setting some control register, patching the kernel code.
  Right now, we treat all caps are enabled at boot-time, after all
  the CPUs are brought up by the kernel. But there are certain caps,
  which are enabled early during the boot (e.g, VHE, GIC_CPUIF for NMI)
  and kernel starts using them, even before the secondary CPUs are brought
  up. We would need a way to describe this for each capability.

 3) Conflict on a late CPU - When a CPU is brought up, it is checked
  against the caps that are known to be enabled on the system (via
  verify_local_cpu_capabilities()). Based on the state of the capability
  on the CPU vs. that of System we could have the following combinations
  of conflict.

	x-----------------------------x
	| Type	| System   | Late CPU |
	------------------------------|
	|  a    |   y      |    n     |
	------------------------------|
	|  b    |   n      |    y     |
	x-----------------------------x

  Case (a) is not permitted for caps which are system features, which the
  system expects all the CPUs to have (e.g VHE). While (a) is ignored for
  all errata work arounds. However, there could be exceptions to the plain
  filtering approach. e.g, KPTI is an optional feature for a late CPU as
  long as the system already enables it.

  Case (b) is not permitted for errata work arounds which requires some
  work around, which cannot be delayed. And we ignore (b) for features.
  Here, yet again, KPTI is an exception, where if a late CPU needs KPTI we
  are too late to enable it (because we change the allocation of ASIDs
  etc).

So this calls for a lot more fine grained behavior for each capability.
And if we define all the attributes to control their behavior properly,
we may be able to use a single table for the CPU hwcaps (which cover
errata and features, not the ELF HWCAPs). This is a prepartory step
to get there. More bits would be added for the properties listed above.

We are going to use a bit-mask to encode all the properties of a
capabilities. This patch encodes the "SCOPE" of the capability.

As such there is no change in how the capabilities are treated.

Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpufeature.h |  105 +++++++++++++++++++++++++++++++++---
 arch/arm64/kernel/cpu_errata.c      |   10 +--
 arch/arm64/kernel/cpufeature.c      |   30 +++++-----
 3 files changed, 119 insertions(+), 26 deletions(-)

--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -66,16 +66,104 @@ struct arm64_ftr_reg {
 
 extern struct arm64_ftr_reg arm64_ftr_reg_ctrel0;
 
-/* scope of capability check */
-enum {
-	SCOPE_SYSTEM,
-	SCOPE_LOCAL_CPU,
-};
+/*
+ * CPU capabilities:
+ *
+ * We use arm64_cpu_capabilities to represent system features, errata work
+ * arounds (both used internally by kernel and tracked in cpu_hwcaps) and
+ * ELF HWCAPs (which are exposed to user).
+ *
+ * To support systems with heterogeneous CPUs, we need to make sure that we
+ * detect the capabilities correctly on the system and take appropriate
+ * measures to ensure there are no incompatibilities.
+ *
+ * This comment tries to explain how we treat the capabilities.
+ * Each capability has the following list of attributes :
+ *
+ * 1) Scope of Detection : The system detects a given capability by
+ *    performing some checks at runtime. This could be, e.g, checking the
+ *    value of a field in CPU ID feature register or checking the cpu
+ *    model. The capability provides a call back ( @matches() ) to
+ *    perform the check. Scope defines how the checks should be performed.
+ *    There are two cases:
+ *
+ *     a) SCOPE_LOCAL_CPU: check all the CPUs and "detect" if at least one
+ *        matches. This implies, we have to run the check on all the
+ *        booting CPUs, until the system decides that state of the
+ *        capability is finalised. (See section 2 below)
+ *		Or
+ *     b) SCOPE_SYSTEM: check all the CPUs and "detect" if all the CPUs
+ *        matches. This implies, we run the check only once, when the
+ *        system decides to finalise the state of the capability. If the
+ *        capability relies on a field in one of the CPU ID feature
+ *        registers, we use the sanitised value of the register from the
+ *        CPU feature infrastructure to make the decision.
+ *
+ *    The process of detection is usually denoted by "update" capability
+ *    state in the code.
+ *
+ * 2) Finalise the state : The kernel should finalise the state of a
+ *    capability at some point during its execution and take necessary
+ *    actions if any. Usually, this is done, after all the boot-time
+ *    enabled CPUs are brought up by the kernel, so that it can make
+ *    better decision based on the available set of CPUs. However, there
+ *    are some special cases, where the action is taken during the early
+ *    boot by the primary boot CPU. (e.g, running the kernel at EL2 with
+ *    Virtualisation Host Extensions). The kernel usually disallows any
+ *    changes to the state of a capability once it finalises the capability
+ *    and takes any action, as it may be impossible to execute the actions
+ *    safely. A CPU brought up after a capability is "finalised" is
+ *    referred to as "Late CPU" w.r.t the capability. e.g, all secondary
+ *    CPUs are treated "late CPUs" for capabilities determined by the boot
+ *    CPU.
+ *
+ * 3) Verification: When a CPU is brought online (e.g, by user or by the
+ *    kernel), the kernel should make sure that it is safe to use the CPU,
+ *    by verifying that the CPU is compliant with the state of the
+ *    capabilities finalised already. This happens via :
+ *
+ *	secondary_start_kernel()-> check_local_cpu_capabilities()
+ *
+ *    As explained in (2) above, capabilities could be finalised at
+ *    different points in the execution. Each CPU is verified against the
+ *    "finalised" capabilities and if there is a conflict, the kernel takes
+ *    an action, based on the severity (e.g, a CPU could be prevented from
+ *    booting or cause a kernel panic). The CPU is allowed to "affect" the
+ *    state of the capability, if it has not been finalised already.
+ *
+ * 4) Action: As mentioned in (2), the kernel can take an action for each
+ *    detected capability, on all CPUs on the system. Appropriate actions
+ *    include, turning on an architectural feature, modifying the control
+ *    registers (e.g, SCTLR, TCR etc.) or patching the kernel via
+ *    alternatives. The kernel patching is batched and performed at later
+ *    point. The actions are always initiated only after the capability
+ *    is finalised. This is usally denoted by "enabling" the capability.
+ *    The actions are initiated as follows :
+ *	a) Action is triggered on all online CPUs, after the capability is
+ *	finalised, invoked within the stop_machine() context from
+ *	enable_cpu_capabilitie().
+ *
+ *	b) Any late CPU, brought up after (1), the action is triggered via:
+ *
+ *	  check_local_cpu_capabilities() -> verify_local_cpu_capabilities()
+ *
+ */
+
+
+/* Decide how the capability is detected. On a local CPU vs System wide */
+#define ARM64_CPUCAP_SCOPE_LOCAL_CPU		((u16)BIT(0))
+#define ARM64_CPUCAP_SCOPE_SYSTEM		((u16)BIT(1))
+#define ARM64_CPUCAP_SCOPE_MASK			\
+	(ARM64_CPUCAP_SCOPE_SYSTEM	|	\
+	 ARM64_CPUCAP_SCOPE_LOCAL_CPU)
+
+#define SCOPE_SYSTEM				ARM64_CPUCAP_SCOPE_SYSTEM
+#define SCOPE_LOCAL_CPU				ARM64_CPUCAP_SCOPE_LOCAL_CPU
 
 struct arm64_cpu_capabilities {
 	const char *desc;
 	u16 capability;
-	int def_scope;			/* default scope */
+	u16 type;
 	bool (*matches)(const struct arm64_cpu_capabilities *caps, int scope);
 	/*
 	 * Take the appropriate actions to enable this capability for this CPU.
@@ -100,6 +188,11 @@ struct arm64_cpu_capabilities {
 	};
 };
 
+static inline int cpucap_default_scope(const struct arm64_cpu_capabilities *cap)
+{
+	return cap->type & ARM64_CPUCAP_SCOPE_MASK;
+}
+
 extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
 extern struct static_key_false cpu_hwcap_keys[ARM64_NCAPS];
 extern struct static_key_false arm64_const_caps_ready;
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -369,14 +369,14 @@ static bool has_ssbd_mitigation(const st
 #endif	/* CONFIG_ARM64_SSBD */
 
 #define MIDR_RANGE(model, min, max) \
-	.def_scope = SCOPE_LOCAL_CPU, \
+	.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, \
 	.matches = is_affected_midr_range, \
 	.midr_model = model, \
 	.midr_range_min = min, \
 	.midr_range_max = max
 
 #define MIDR_ALL_VERSIONS(model) \
-	.def_scope = SCOPE_LOCAL_CPU, \
+	.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, \
 	.matches = is_affected_midr_range, \
 	.midr_model = model, \
 	.midr_range_min = 0, \
@@ -459,14 +459,14 @@ const struct arm64_cpu_capabilities arm6
 		.desc = "Mismatched cache line size",
 		.capability = ARM64_MISMATCHED_CACHE_LINE_SIZE,
 		.matches = has_mismatched_cache_type,
-		.def_scope = SCOPE_LOCAL_CPU,
+		.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU,
 		.cpu_enable = cpu_enable_trap_ctr_access,
 	},
 	{
 		.desc = "Mismatched cache type",
 		.capability = ARM64_MISMATCHED_CACHE_TYPE,
 		.matches = has_mismatched_cache_type,
-		.def_scope = SCOPE_LOCAL_CPU,
+		.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU,
 		.cpu_enable = cpu_enable_trap_ctr_access,
 	},
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
@@ -504,7 +504,7 @@ const struct arm64_cpu_capabilities arm6
 #ifdef CONFIG_ARM64_SSBD
 	{
 		.desc = "Speculative Store Bypass Disable",
-		.def_scope = SCOPE_LOCAL_CPU,
+		.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU,
 		.capability = ARM64_SSBD,
 		.matches = has_ssbd_mitigation,
 	},
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -865,7 +865,7 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "GIC system register CPU interface",
 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = has_useable_gicv3_cpuif,
 		.sys_reg = SYS_ID_AA64PFR0_EL1,
 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
@@ -876,7 +876,7 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "Privileged Access Never",
 		.capability = ARM64_HAS_PAN,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
@@ -889,7 +889,7 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "LSE atomic instructions",
 		.capability = ARM64_HAS_LSE_ATOMICS,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
@@ -900,14 +900,14 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "Software prefetching using PRFM",
 		.capability = ARM64_HAS_NO_HW_PREFETCH,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = has_no_hw_prefetch,
 	},
 #ifdef CONFIG_ARM64_UAO
 	{
 		.desc = "User Access Override",
 		.capability = ARM64_HAS_UAO,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
@@ -921,21 +921,21 @@ static const struct arm64_cpu_capabiliti
 #ifdef CONFIG_ARM64_PAN
 	{
 		.capability = ARM64_ALT_PAN_NOT_UAO,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = cpufeature_pan_not_uao,
 	},
 #endif /* CONFIG_ARM64_PAN */
 	{
 		.desc = "Virtualization Host Extensions",
 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = runs_at_el2,
 		.cpu_enable = cpu_copy_el2regs,
 	},
 	{
 		.desc = "32-bit EL0 Support",
 		.capability = ARM64_HAS_32BIT_EL0,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64PFR0_EL1,
 		.sign = FTR_UNSIGNED,
@@ -945,14 +945,14 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "Reduced HYP mapping offset",
 		.capability = ARM64_HYP_OFFSET_LOW,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = hyp_offset_low,
 	},
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 	{
 		.desc = "Kernel page table isolation (KPTI)",
 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
-		.def_scope = SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
 		.matches = unmap_kernel_at_el0,
 		.cpu_enable = kpti_install_ng_mappings,
 	},
@@ -960,16 +960,16 @@ static const struct arm64_cpu_capabiliti
 	{},
 };
 
-#define HWCAP_CAP(reg, field, s, min_value, type, cap)	\
+#define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)	\
 	{							\
 		.desc = #cap,					\
-		.def_scope = SCOPE_SYSTEM,			\
+		.type = ARM64_CPUCAP_SCOPE_SYSTEM,		\
 		.matches = has_cpuid_feature,			\
 		.sys_reg = reg,					\
 		.field_pos = field,				\
 		.sign = s,					\
 		.min_field_value = min_value,			\
-		.hwcap_type = type,				\
+		.hwcap_type = cap_type,				\
 		.hwcap = cap,					\
 	}
 
@@ -1046,7 +1046,7 @@ static bool cpus_have_elf_hwcap(const st
 static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
 {
 	for (; hwcaps->matches; hwcaps++)
-		if (hwcaps->matches(hwcaps, hwcaps->def_scope))
+		if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps)))
 			cap_set_elf_hwcap(hwcaps);
 }
 
@@ -1073,7 +1073,7 @@ static void update_cpu_capabilities(cons
 				    const char *info)
 {
 	for (; caps->matches; caps++) {
-		if (!caps->matches(caps, caps->def_scope))
+		if (!caps->matches(caps, cpucap_default_scope(caps)))
 			continue;
 
 		if (!cpus_have_cap(caps->capability) && caps->desc)

[PATCH 4.9 08/43] arm64: capabilities: Add flags to handle the conflicts on late CPU

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit 5b4747c5dce7a873e1e7fe1608835825f714267a ]

When a CPU is brought up, it is checked against the caps that are
known to be enabled on the system (via verify_local_cpu_capabilities()).
Based on the state of the capability on the CPU vs. that of System we
could have the following combinations of conflict.

	x-----------------------------x
	| Type  | System   | Late CPU |
	|-----------------------------|
	|  a    |   y      |    n     |
	|-----------------------------|
	|  b    |   n      |    y     |
	x-----------------------------x

Case (a) is not permitted for caps which are system features, which the
system expects all the CPUs to have (e.g VHE). While (a) is ignored for
all errata work arounds. However, there could be exceptions to the plain
filtering approach. e.g, KPTI is an optional feature for a late CPU as
long as the system already enables it.

Case (b) is not permitted for errata work arounds that cannot be activated
after the kernel has finished booting.And we ignore (b) for features. Here,
yet again, KPTI is an exception, where if a late CPU needs KPTI we are too
late to enable it (because we change the allocation of ASIDs etc).

Add two different flags to indicate how the conflict should be handled.

 ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU - CPUs may have the capability
 ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU - CPUs may not have the cappability.

Now that we have the flags to describe the behavior of the errata and
the features, as we treat them, define types for ERRATUM and FEATURE.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpufeature.h |   68 ++++++++++++++++++++++++++++++++++++
 arch/arm64/kernel/cpu_errata.c      |   10 ++---
 arch/arm64/kernel/cpufeature.c      |   22 +++++------
 3 files changed, 84 insertions(+), 16 deletions(-)

--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -130,6 +130,7 @@ extern struct arm64_ftr_reg arm64_ftr_re
  *    an action, based on the severity (e.g, a CPU could be prevented from
  *    booting or cause a kernel panic). The CPU is allowed to "affect" the
  *    state of the capability, if it has not been finalised already.
+ *    See section 5 for more details on conflicts.
  *
  * 4) Action: As mentioned in (2), the kernel can take an action for each
  *    detected capability, on all CPUs on the system. Appropriate actions
@@ -147,6 +148,34 @@ extern struct arm64_ftr_reg arm64_ftr_re
  *
  *	  check_local_cpu_capabilities() -> verify_local_cpu_capabilities()
  *
+ * 5) Conflicts: Based on the state of the capability on a late CPU vs.
+ *    the system state, we could have the following combinations :
+ *
+ *		x-----------------------------x
+ *		| Type  | System   | Late CPU |
+ *		|-----------------------------|
+ *		|  a    |   y      |    n     |
+ *		|-----------------------------|
+ *		|  b    |   n      |    y     |
+ *		x-----------------------------x
+ *
+ *     Two separate flag bits are defined to indicate whether each kind of
+ *     conflict can be allowed:
+ *		ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU - Case(a) is allowed
+ *		ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU - Case(b) is allowed
+ *
+ *     Case (a) is not permitted for a capability that the system requires
+ *     all CPUs to have in order for the capability to be enabled. This is
+ *     typical for capabilities that represent enhanced functionality.
+ *
+ *     Case (b) is not permitted for a capability that must be enabled
+ *     during boot if any CPU in the system requires it in order to run
+ *     safely. This is typical for erratum work arounds that cannot be
+ *     enabled after the corresponding capability is finalised.
+ *
+ *     In some non-typical cases either both (a) and (b), or neither,
+ *     should be permitted. This can be described by including neither
+ *     or both flags in the capability's type field.
  */
 
 
@@ -160,6 +189,33 @@ extern struct arm64_ftr_reg arm64_ftr_re
 #define SCOPE_SYSTEM				ARM64_CPUCAP_SCOPE_SYSTEM
 #define SCOPE_LOCAL_CPU				ARM64_CPUCAP_SCOPE_LOCAL_CPU
 
+/*
+ * Is it permitted for a late CPU to have this capability when system
+ * hasn't already enabled it ?
+ */
+#define ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU	((u16)BIT(4))
+/* Is it safe for a late CPU to miss this capability when system has it */
+#define ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU	((u16)BIT(5))
+
+/*
+ * CPU errata workarounds that need to be enabled at boot time if one or
+ * more CPUs in the system requires it. When one of these capabilities
+ * has been enabled, it is safe to allow any CPU to boot that doesn't
+ * require the workaround. However, it is not safe if a "late" CPU
+ * requires a workaround and the system hasn't enabled it already.
+ */
+#define ARM64_CPUCAP_LOCAL_CPU_ERRATUM		\
+	(ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU)
+/*
+ * CPU feature detected at boot time based on system-wide value of a
+ * feature. It is safe for a late CPU to have this feature even though
+ * the system hasn't enabled it, although the featuer will not be used
+ * by Linux in this case. If the system has enabled this feature already,
+ * then every late CPU must have it.
+ */
+#define ARM64_CPUCAP_SYSTEM_FEATURE	\
+	(ARM64_CPUCAP_SCOPE_SYSTEM | ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU)
+
 struct arm64_cpu_capabilities {
 	const char *desc;
 	u16 capability;
@@ -193,6 +249,18 @@ static inline int cpucap_default_scope(c
 	return cap->type & ARM64_CPUCAP_SCOPE_MASK;
 }
 
+static inline bool
+cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
+{
+	return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU);
+}
+
+static inline bool
+cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap)
+{
+	return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU);
+}
+
 extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
 extern struct static_key_false cpu_hwcap_keys[ARM64_NCAPS];
 extern struct static_key_false arm64_const_caps_ready;
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -369,14 +369,14 @@ static bool has_ssbd_mitigation(const st
 #endif	/* CONFIG_ARM64_SSBD */
 
 #define MIDR_RANGE(model, min, max) \
-	.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, \
+	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \
 	.matches = is_affected_midr_range, \
 	.midr_model = model, \
 	.midr_range_min = min, \
 	.midr_range_max = max
 
 #define MIDR_ALL_VERSIONS(model) \
-	.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, \
+	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \
 	.matches = is_affected_midr_range, \
 	.midr_model = model, \
 	.midr_range_min = 0, \
@@ -459,14 +459,14 @@ const struct arm64_cpu_capabilities arm6
 		.desc = "Mismatched cache line size",
 		.capability = ARM64_MISMATCHED_CACHE_LINE_SIZE,
 		.matches = has_mismatched_cache_type,
-		.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU,
+		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
 		.cpu_enable = cpu_enable_trap_ctr_access,
 	},
 	{
 		.desc = "Mismatched cache type",
 		.capability = ARM64_MISMATCHED_CACHE_TYPE,
 		.matches = has_mismatched_cache_type,
-		.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU,
+		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
 		.cpu_enable = cpu_enable_trap_ctr_access,
 	},
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
@@ -504,7 +504,7 @@ const struct arm64_cpu_capabilities arm6
 #ifdef CONFIG_ARM64_SSBD
 	{
 		.desc = "Speculative Store Bypass Disable",
-		.type = ARM64_CPUCAP_SCOPE_LOCAL_CPU,
+		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
 		.capability = ARM64_SSBD,
 		.matches = has_ssbd_mitigation,
 	},
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -865,7 +865,7 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "GIC system register CPU interface",
 		.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = has_useable_gicv3_cpuif,
 		.sys_reg = SYS_ID_AA64PFR0_EL1,
 		.field_pos = ID_AA64PFR0_GIC_SHIFT,
@@ -876,7 +876,7 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "Privileged Access Never",
 		.capability = ARM64_HAS_PAN,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64MMFR1_EL1,
 		.field_pos = ID_AA64MMFR1_PAN_SHIFT,
@@ -889,7 +889,7 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "LSE atomic instructions",
 		.capability = ARM64_HAS_LSE_ATOMICS,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64ISAR0_EL1,
 		.field_pos = ID_AA64ISAR0_ATOMICS_SHIFT,
@@ -900,14 +900,14 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "Software prefetching using PRFM",
 		.capability = ARM64_HAS_NO_HW_PREFETCH,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = has_no_hw_prefetch,
 	},
 #ifdef CONFIG_ARM64_UAO
 	{
 		.desc = "User Access Override",
 		.capability = ARM64_HAS_UAO,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64MMFR2_EL1,
 		.field_pos = ID_AA64MMFR2_UAO_SHIFT,
@@ -921,21 +921,21 @@ static const struct arm64_cpu_capabiliti
 #ifdef CONFIG_ARM64_PAN
 	{
 		.capability = ARM64_ALT_PAN_NOT_UAO,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = cpufeature_pan_not_uao,
 	},
 #endif /* CONFIG_ARM64_PAN */
 	{
 		.desc = "Virtualization Host Extensions",
 		.capability = ARM64_HAS_VIRT_HOST_EXTN,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = runs_at_el2,
 		.cpu_enable = cpu_copy_el2regs,
 	},
 	{
 		.desc = "32-bit EL0 Support",
 		.capability = ARM64_HAS_32BIT_EL0,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = has_cpuid_feature,
 		.sys_reg = SYS_ID_AA64PFR0_EL1,
 		.sign = FTR_UNSIGNED,
@@ -945,14 +945,14 @@ static const struct arm64_cpu_capabiliti
 	{
 		.desc = "Reduced HYP mapping offset",
 		.capability = ARM64_HYP_OFFSET_LOW,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = hyp_offset_low,
 	},
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 	{
 		.desc = "Kernel page table isolation (KPTI)",
 		.capability = ARM64_UNMAP_KERNEL_AT_EL0,
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
 		.matches = unmap_kernel_at_el0,
 		.cpu_enable = kpti_install_ng_mappings,
 	},
@@ -963,7 +963,7 @@ static const struct arm64_cpu_capabiliti
 #define HWCAP_CAP(reg, field, s, min_value, cap_type, cap)	\
 	{							\
 		.desc = #cap,					\
-		.type = ARM64_CPUCAP_SCOPE_SYSTEM,		\
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,		\
 		.matches = has_cpuid_feature,			\
 		.sys_reg = reg,					\
 		.field_pos = field,				\

[PATCH 4.9 09/43] arm64: capabilities: Clean up midr range helpers

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit 5e7951ce19abf4113645ae789c033917356ee96f ]

We are about to introduce generic MIDR range helpers. Clean
up the existing helpers in erratum handling, preparing them
to use generic version.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/cpu_errata.c |   82 +++++++++++++++++++++++++----------------
 1 file changed, 50 insertions(+), 32 deletions(-)

--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -368,20 +368,38 @@ static bool has_ssbd_mitigation(const st
 }
 #endif	/* CONFIG_ARM64_SSBD */
 
-#define MIDR_RANGE(model, min, max) \
-	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \
-	.matches = is_affected_midr_range, \
-	.midr_model = model, \
-	.midr_range_min = min, \
-	.midr_range_max = max
-
-#define MIDR_ALL_VERSIONS(model) \
-	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \
-	.matches = is_affected_midr_range, \
-	.midr_model = model, \
-	.midr_range_min = 0, \
+#define CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max)	\
+	.matches = is_affected_midr_range,			\
+	.midr_model = model,					\
+	.midr_range_min = MIDR_CPU_VAR_REV(v_min, r_min),	\
+	.midr_range_max = MIDR_CPU_VAR_REV(v_max, r_max)
+
+#define CAP_MIDR_ALL_VERSIONS(model)					\
+	.matches = is_affected_midr_range,				\
+	.midr_model = model,						\
+	.midr_range_min = MIDR_CPU_VAR_REV(0, 0),			\
 	.midr_range_max = (MIDR_VARIANT_MASK | MIDR_REVISION_MASK)
 
+#define MIDR_FIXED(rev, revidr_mask) \
+	.fixed_revs = (struct arm64_midr_revidr[]){{ (rev), (revidr_mask) }, {}}
+
+#define ERRATA_MIDR_RANGE(model, v_min, r_min, v_max, r_max)		\
+	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,				\
+	CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max)
+
+/* Errata affecting a range of revisions of  given model variant */
+#define ERRATA_MIDR_REV_RANGE(m, var, r_min, r_max)	 \
+	ERRATA_MIDR_RANGE(m, var, r_min, var, r_max)
+
+/* Errata affecting a single variant/revision of a model */
+#define ERRATA_MIDR_REV(model, var, rev)	\
+	ERRATA_MIDR_RANGE(model, var, rev, var, rev)
+
+/* Errata affecting all variants/revisions of a given a model */
+#define ERRATA_MIDR_ALL_VERSIONS(model)				\
+	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,			\
+	CAP_MIDR_ALL_VERSIONS(model)
+
 const struct arm64_cpu_capabilities arm64_errata[] = {
 #if	defined(CONFIG_ARM64_ERRATUM_826319) || \
 	defined(CONFIG_ARM64_ERRATUM_827319) || \
@@ -390,7 +408,7 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A53 r0p[012] */
 		.desc = "ARM errata 826319, 827319, 824069",
 		.capability = ARM64_WORKAROUND_CLEAN_CACHE,
-		MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x02),
+		ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 2),
 		.cpu_enable = cpu_enable_cache_maint_trap,
 	},
 #endif
@@ -399,7 +417,7 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A53 r0p[01] */
 		.desc = "ARM errata 819472",
 		.capability = ARM64_WORKAROUND_CLEAN_CACHE,
-		MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x01),
+		ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 1),
 		.cpu_enable = cpu_enable_cache_maint_trap,
 	},
 #endif
@@ -408,9 +426,9 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A57 r0p0 - r1p2 */
 		.desc = "ARM erratum 832075",
 		.capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE,
-		MIDR_RANGE(MIDR_CORTEX_A57,
-			   MIDR_CPU_VAR_REV(0, 0),
-			   MIDR_CPU_VAR_REV(1, 2)),
+		ERRATA_MIDR_RANGE(MIDR_CORTEX_A57,
+				  0, 0,
+				  1, 2),
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_834220
@@ -418,9 +436,9 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A57 r0p0 - r1p2 */
 		.desc = "ARM erratum 834220",
 		.capability = ARM64_WORKAROUND_834220,
-		MIDR_RANGE(MIDR_CORTEX_A57,
-			   MIDR_CPU_VAR_REV(0, 0),
-			   MIDR_CPU_VAR_REV(1, 2)),
+		ERRATA_MIDR_RANGE(MIDR_CORTEX_A57,
+				  0, 0,
+				  1, 2),
 	},
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_845719
@@ -428,7 +446,7 @@ const struct arm64_cpu_capabilities arm6
 	/* Cortex-A53 r0p[01234] */
 		.desc = "ARM erratum 845719",
 		.capability = ARM64_WORKAROUND_845719,
-		MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x04),
+		ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 4),
 	},
 #endif
 #ifdef CONFIG_CAVIUM_ERRATUM_23154
@@ -436,7 +454,7 @@ const struct arm64_cpu_capabilities arm6
 	/* Cavium ThunderX, pass 1.x */
 		.desc = "Cavium erratum 23154",
 		.capability = ARM64_WORKAROUND_CAVIUM_23154,
-		MIDR_RANGE(MIDR_THUNDERX, 0x00, 0x01),
+		ERRATA_MIDR_REV_RANGE(MIDR_THUNDERX, 0, 0, 1),
 	},
 #endif
 #ifdef CONFIG_CAVIUM_ERRATUM_27456
@@ -444,15 +462,15 @@ const struct arm64_cpu_capabilities arm6
 	/* Cavium ThunderX, T88 pass 1.x - 2.1 */
 		.desc = "Cavium erratum 27456",
 		.capability = ARM64_WORKAROUND_CAVIUM_27456,
-		MIDR_RANGE(MIDR_THUNDERX,
-			   MIDR_CPU_VAR_REV(0, 0),
-			   MIDR_CPU_VAR_REV(1, 1)),
+		ERRATA_MIDR_RANGE(MIDR_THUNDERX,
+				  0, 0,
+				  1, 1),
 	},
 	{
 	/* Cavium ThunderX, T81 pass 1.0 */
 		.desc = "Cavium erratum 27456",
 		.capability = ARM64_WORKAROUND_CAVIUM_27456,
-		MIDR_RANGE(MIDR_THUNDERX_81XX, 0x00, 0x00),
+		ERRATA_MIDR_REV(MIDR_THUNDERX_81XX, 0, 0),
 	},
 #endif
 	{
@@ -472,32 +490,32 @@ const struct arm64_cpu_capabilities arm6
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
+		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
+		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
+		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
+		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
+		ERRATA_MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
+		ERRATA_MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 #endif

[PATCH 4.9 10/43] arm64: Add helpers for checking CPU MIDR against a range

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit 1df310505d6d544802016f6bae49aab836ae8510 ]

Add helpers for checking if the given CPU midr falls in a range
of variants/revisions for a given model.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpufeature.h |    4 ++--
 arch/arm64/include/asm/cputype.h    |   30 ++++++++++++++++++++++++++++++
 arch/arm64/kernel/cpu_errata.c      |   14 +++++---------
 3 files changed, 37 insertions(+), 11 deletions(-)

--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -10,6 +10,7 @@
 #define __ASM_CPUFEATURE_H
 
 #include <asm/cpucaps.h>
+#include <asm/cputype.h>
 #include <asm/hwcap.h>
 #include <asm/sysreg.h>
 
@@ -229,8 +230,7 @@ struct arm64_cpu_capabilities {
 	void (*cpu_enable)(const struct arm64_cpu_capabilities *cap);
 	union {
 		struct {	/* To be used for erratum handling only */
-			u32 midr_model;
-			u32 midr_range_min, midr_range_max;
+			struct midr_range midr_range;
 		};
 
 		struct {	/* Feature register checking */
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -114,6 +114,36 @@
 #define read_cpuid(reg)			read_sysreg_s(SYS_ ## reg)
 
 /*
+ * Represent a range of MIDR values for a given CPU model and a
+ * range of variant/revision values.
+ *
+ * @model	- CPU model as defined by MIDR_CPU_MODEL
+ * @rv_min	- Minimum value for the revision/variant as defined by
+ *		  MIDR_CPU_VAR_REV
+ * @rv_max	- Maximum value for the variant/revision for the range.
+ */
+struct midr_range {
+	u32 model;
+	u32 rv_min;
+	u32 rv_max;
+};
+
+#define MIDR_RANGE(m, v_min, r_min, v_max, r_max)		\
+	{							\
+		.model = m,					\
+		.rv_min = MIDR_CPU_VAR_REV(v_min, r_min),	\
+		.rv_max = MIDR_CPU_VAR_REV(v_max, r_max),	\
+	}
+
+#define MIDR_ALL_VERSIONS(m) MIDR_RANGE(m, 0, 0, 0xf, 0xf)
+
+static inline bool is_midr_in_range(u32 midr, struct midr_range const *range)
+{
+	return MIDR_IS_CPU_MODEL_RANGE(midr, range->model,
+				 range->rv_min, range->rv_max);
+}
+
+/*
  * The CPU ID never changes at run time, so we might as well tell the
  * compiler that it's constant.  Use this function to read the CPU ID
  * rather than directly reading processor_id or read_cpuid() directly.
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -27,10 +27,10 @@
 static bool __maybe_unused
 is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope)
 {
+	u32 midr = read_cpuid_id();
+
 	WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
-	return MIDR_IS_CPU_MODEL_RANGE(read_cpuid_id(), entry->midr_model,
-				       entry->midr_range_min,
-				       entry->midr_range_max);
+	return is_midr_in_range(midr, &entry->midr_range);
 }
 
 static bool
@@ -370,15 +370,11 @@ static bool has_ssbd_mitigation(const st
 
 #define CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max)	\
 	.matches = is_affected_midr_range,			\
-	.midr_model = model,					\
-	.midr_range_min = MIDR_CPU_VAR_REV(v_min, r_min),	\
-	.midr_range_max = MIDR_CPU_VAR_REV(v_max, r_max)
+	.midr_range = MIDR_RANGE(model, v_min, r_min, v_max, r_max)
 
 #define CAP_MIDR_ALL_VERSIONS(model)					\
 	.matches = is_affected_midr_range,				\
-	.midr_model = model,						\
-	.midr_range_min = MIDR_CPU_VAR_REV(0, 0),			\
-	.midr_range_max = (MIDR_VARIANT_MASK | MIDR_REVISION_MASK)
+	.midr_range = MIDR_ALL_VERSIONS(model)
 
 #define MIDR_FIXED(rev, revidr_mask) \
 	.fixed_revs = (struct arm64_midr_revidr[]){{ (rev), (revidr_mask) }, {}}

[PATCH 4.9 11/43] arm64: capabilities: Add support for checks based on a list of MIDRs

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

[ Upstream commit be5b299830c63ed76e0357473c4218c85fb388b3 ]

Add helpers for detecting an errata on list of midr ranges
of affected CPUs, with the same work around.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
[ardb: add Cortex-A35 to kpti_safe_list[] as well]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpufeature.h |    1 
 arch/arm64/include/asm/cputype.h    |    9 +++++
 arch/arm64/kernel/cpu_errata.c      |   62 ++++++++++++++++++++----------------
 arch/arm64/kernel/cpufeature.c      |   21 ++++++------
 4 files changed, 58 insertions(+), 35 deletions(-)

--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -233,6 +233,7 @@ struct arm64_cpu_capabilities {
 			struct midr_range midr_range;
 		};
 
+		const struct midr_range *midr_range_list;
 		struct {	/* Feature register checking */
 			u32 sys_reg;
 			u8 field_pos;
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -143,6 +143,15 @@ static inline bool is_midr_in_range(u32
 				 range->rv_min, range->rv_max);
 }
 
+static inline bool
+is_midr_in_range_list(u32 midr, struct midr_range const *ranges)
+{
+	while (ranges->model)
+		if (is_midr_in_range(midr, ranges++))
+			return true;
+	return false;
+}
+
 /*
  * The CPU ID never changes at run time, so we might as well tell the
  * compiler that it's constant.  Use this function to read the CPU ID
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -33,6 +33,14 @@ is_affected_midr_range(const struct arm6
 	return is_midr_in_range(midr, &entry->midr_range);
 }
 
+static bool __maybe_unused
+is_affected_midr_range_list(const struct arm64_cpu_capabilities *entry,
+			    int scope)
+{
+	WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
+	return is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list);
+}
+
 static bool
 has_mismatched_cache_type(const struct arm64_cpu_capabilities *entry,
 			  int scope)
@@ -383,6 +391,10 @@ static bool has_ssbd_mitigation(const st
 	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,				\
 	CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max)
 
+#define CAP_MIDR_RANGE_LIST(list)				\
+	.matches = is_affected_midr_range_list,			\
+	.midr_range_list = list
+
 /* Errata affecting a range of revisions of  given model variant */
 #define ERRATA_MIDR_REV_RANGE(m, var, r_min, r_max)	 \
 	ERRATA_MIDR_RANGE(m, var, r_min, var, r_max)
@@ -396,6 +408,29 @@ static bool has_ssbd_mitigation(const st
 	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,			\
 	CAP_MIDR_ALL_VERSIONS(model)
 
+/* Errata affecting a list of midr ranges, with same work around */
+#define ERRATA_MIDR_RANGE_LIST(midr_list)			\
+	.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,			\
+	CAP_MIDR_RANGE_LIST(midr_list)
+
+#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
+
+/*
+ * List of CPUs where we need to issue a psci call to
+ * harden the branch predictor.
+ */
+static const struct midr_range arm64_bp_harden_smccc_cpus[] = {
+	MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
+	MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
+	MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
+	MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
+	MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
+	MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
+	{},
+};
+
+#endif
+
 const struct arm64_cpu_capabilities arm64_errata[] = {
 #if	defined(CONFIG_ARM64_ERRATUM_826319) || \
 	defined(CONFIG_ARM64_ERRATUM_827319) || \
@@ -486,32 +521,7 @@ const struct arm64_cpu_capabilities arm6
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
 	{
 		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
-		.cpu_enable = enable_smccc_arch_workaround_1,
-	},
-	{
-		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
-		.cpu_enable = enable_smccc_arch_workaround_1,
-	},
-	{
-		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
-		.cpu_enable = enable_smccc_arch_workaround_1,
-	},
-	{
-		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
-		.cpu_enable = enable_smccc_arch_workaround_1,
-	},
-	{
-		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		ERRATA_MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
-		.cpu_enable = enable_smccc_arch_workaround_1,
-	},
-	{
-		.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
-		ERRATA_MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
+		ERRATA_MIDR_RANGE_LIST(arm64_bp_harden_smccc_cpus),
 		.cpu_enable = enable_smccc_arch_workaround_1,
 	},
 #endif
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -767,6 +767,17 @@ static int __kpti_forced; /* 0: not forc
 static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry,
 				int __unused)
 {
+	/* List of CPUs that are not vulnerable and don't need KPTI */
+	static const struct midr_range kpti_safe_list[] = {
+		MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
+		MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A35),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A53),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A55),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
+	};
 	char const *str = "command line option";
 	u64 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1);
 
@@ -792,16 +803,8 @@ static bool unmap_kernel_at_el0(const st
 		return true;
 
 	/* Don't force KPTI for CPUs that are not vulnerable */
-	switch (read_cpuid_id() & MIDR_CPU_MODEL_MASK) {
-	case MIDR_CAVIUM_THUNDERX2:
-	case MIDR_BRCM_VULCAN:
-	case MIDR_CORTEX_A53:
-	case MIDR_CORTEX_A55:
-	case MIDR_CORTEX_A57:
-	case MIDR_CORTEX_A72:
-	case MIDR_CORTEX_A73:
+	if (is_midr_in_range_list(read_cpuid_id(), kpti_safe_list))
 		return false;
-	}
 
 	/* Defer to CPU feature registers */
 	return !cpuid_feature_extract_unsigned_field(pfr0,

[PATCH 4.9 12/43] clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameter

[Greg Kroah-Hartman]

From: Ding Tianhong <dingtianhong@huawei.com>

commit 5444ea6a7f46276876e94ecf8d44615af1ef22f7 upstream.

Having a command line option to flip the errata handling for a
particular erratum is a little bit unusual, and it's vastly superior to
pass this in the DT. By common consensus, it's best to kill off the
command line parameter.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
[Mark: split patch, reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 Documentation/kernel-parameters.txt  |    9 ---------
 drivers/clocksource/arm_arch_timer.c |   14 --------------
 2 files changed, 23 deletions(-)

--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -751,15 +751,6 @@ bytes respectively. Such letter suffixes
 			loops can be debugged more effectively on production
 			systems.
 
-	clocksource.arm_arch_timer.fsl-a008585=
-			[ARM64]
-			Format: <bool>
-			Enable/disable the workaround of Freescale/NXP
-			erratum A-008585.  This can be useful for KVM
-			guests, if the guest device tree doesn't show the
-			erratum.  If unspecified, the workaround is
-			enabled based on the device tree.
-
 	clearcpuid=BITNUM [X86]
 			Disable CPUID feature X for the kernel. See
 			arch/x86/include/asm/cpufeatures.h for the valid bit
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -101,20 +101,6 @@ EXPORT_SYMBOL_GPL(arch_timer_read_ool_en
 
 static int fsl_a008585_enable = -1;
 
-static int __init early_fsl_a008585_cfg(char *buf)
-{
-	int ret;
-	bool val;
-
-	ret = strtobool(buf, &val);
-	if (ret)
-		return ret;
-
-	fsl_a008585_enable = val;
-	return 0;
-}
-early_param("clocksource.arm_arch_timer.fsl-a008585", early_fsl_a008585_cfg);
-
 u32 __fsl_a008585_read_cntp_tval_el0(void)
 {
 	return __fsl_a008585_read_reg(cntp_tval_el0);

[PATCH 4.9 13/43] clocksource/drivers/arm_arch_timer: Introduce generic errata handling infrastructure

[Greg Kroah-Hartman]

From: Ding Tianhong <dingtianhong@huawei.com>

commit 16d10ef29f25aba923779234bb93a451b14d20e6 upstream.

Currently we have code inline in the arch timer probe path to cater for
Freescale erratum A-008585, complete with ifdeffery. This is a little
ugly, and will get worse as we try to add more errata handling.

This patch refactors the handling of Freescale erratum A-008585. Now the
erratum is described in a generic arch_timer_erratum_workaround
structure, and the probe path can iterate over these to detect errata
and enable workarounds.

This will simplify the addition and maintenance of code handling
Hisilicon erratum 161010101.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
[Mark: split patch, correct Kconfig, reword commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/arch_timer.h  |   40 +++++----------
 drivers/clocksource/Kconfig          |    4 +
 drivers/clocksource/arm_arch_timer.c |   90 ++++++++++++++++++++++++-----------
 3 files changed, 80 insertions(+), 54 deletions(-)

--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -29,41 +29,29 @@
 
 #include <clocksource/arm_arch_timer.h>
 
-#if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585)
+#if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND)
 extern struct static_key_false arch_timer_read_ool_enabled;
-#define needs_fsl_a008585_workaround() \
+#define needs_unstable_timer_counter_workaround() \
 	static_branch_unlikely(&arch_timer_read_ool_enabled)
 #else
-#define needs_fsl_a008585_workaround()  false
+#define needs_unstable_timer_counter_workaround()  false
 #endif
 
-u32 __fsl_a008585_read_cntp_tval_el0(void);
-u32 __fsl_a008585_read_cntv_tval_el0(void);
-u64 __fsl_a008585_read_cntvct_el0(void);
-
-/*
- * The number of retries is an arbitrary value well beyond the highest number
- * of iterations the loop has been observed to take.
- */
-#define __fsl_a008585_read_reg(reg) ({			\
-	u64 _old, _new;					\
-	int _retries = 200;				\
-							\
-	do {						\
-		_old = read_sysreg(reg);		\
-		_new = read_sysreg(reg);		\
-		_retries--;				\
-	} while (unlikely(_old != _new) && _retries);	\
-							\
-	WARN_ON_ONCE(!_retries);			\
-	_new;						\
-})
+
+struct arch_timer_erratum_workaround {
+	const char *id;		/* Indicate the Erratum ID */
+	u32 (*read_cntp_tval_el0)(void);
+	u32 (*read_cntv_tval_el0)(void);
+	u64 (*read_cntvct_el0)(void);
+};
+
+extern const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround;
 
 #define arch_timer_reg_read_stable(reg) 		\
 ({							\
 	u64 _val;					\
-	if (needs_fsl_a008585_workaround())		\
-		_val = __fsl_a008585_read_##reg();	\
+	if (needs_unstable_timer_counter_workaround())		\
+		_val = timer_unstable_counter_workaround->read_##reg();\
 	else						\
 		_val = read_sysreg(reg);		\
 	_val;						\
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -305,10 +305,14 @@ config ARM_ARCH_TIMER_EVTSTREAM
 	  This must be disabled for hardware validation purposes to detect any
 	  hardware anomalies of missing events.
 
+config ARM_ARCH_TIMER_OOL_WORKAROUND
+	bool
+
 config FSL_ERRATUM_A008585
 	bool "Workaround for Freescale/NXP Erratum A-008585"
 	default y
 	depends on ARM_ARCH_TIMER && ARM64
+	select ARM_ARCH_TIMER_OOL_WORKAROUND
 	help
 	  This option enables a workaround for Freescale/NXP Erratum
 	  A-008585 ("ARM generic timer may contain an erroneous
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -96,27 +96,58 @@ early_param("clocksource.arm_arch_timer.
  */
 
 #ifdef CONFIG_FSL_ERRATUM_A008585
-DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled);
-EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled);
-
-static int fsl_a008585_enable = -1;
+/*
+ * The number of retries is an arbitrary value well beyond the highest number
+ * of iterations the loop has been observed to take.
+ */
+#define __fsl_a008585_read_reg(reg) ({			\
+	u64 _old, _new;					\
+	int _retries = 200;				\
+							\
+	do {						\
+		_old = read_sysreg(reg);		\
+		_new = read_sysreg(reg);		\
+		_retries--;				\
+	} while (unlikely(_old != _new) && _retries);	\
+							\
+	WARN_ON_ONCE(!_retries);			\
+	_new;						\
+})
 
-u32 __fsl_a008585_read_cntp_tval_el0(void)
+static u32 notrace fsl_a008585_read_cntp_tval_el0(void)
 {
 	return __fsl_a008585_read_reg(cntp_tval_el0);
 }
 
-u32 __fsl_a008585_read_cntv_tval_el0(void)
+static u32 notrace fsl_a008585_read_cntv_tval_el0(void)
 {
 	return __fsl_a008585_read_reg(cntv_tval_el0);
 }
 
-u64 __fsl_a008585_read_cntvct_el0(void)
+static u64 notrace fsl_a008585_read_cntvct_el0(void)
 {
 	return __fsl_a008585_read_reg(cntvct_el0);
 }
-EXPORT_SYMBOL(__fsl_a008585_read_cntvct_el0);
-#endif /* CONFIG_FSL_ERRATUM_A008585 */
+#endif
+
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround = NULL;
+EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround);
+
+DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled);
+EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled);
+
+static const struct arch_timer_erratum_workaround ool_workarounds[] = {
+#ifdef CONFIG_FSL_ERRATUM_A008585
+	{
+		.id = "fsl,erratum-a008585",
+		.read_cntp_tval_el0 = fsl_a008585_read_cntp_tval_el0,
+		.read_cntv_tval_el0 = fsl_a008585_read_cntv_tval_el0,
+		.read_cntvct_el0 = fsl_a008585_read_cntvct_el0,
+	},
+#endif
+};
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
 
 static __always_inline
 void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
@@ -267,8 +298,8 @@ static __always_inline void set_next_eve
 	arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
 }
 
-#ifdef CONFIG_FSL_ERRATUM_A008585
-static __always_inline void fsl_a008585_set_next_event(const int access,
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+static __always_inline void erratum_set_next_event_generic(const int access,
 		unsigned long evt, struct clock_event_device *clk)
 {
 	unsigned long ctrl;
@@ -286,20 +317,20 @@ static __always_inline void fsl_a008585_
 	arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
 }
 
-static int fsl_a008585_set_next_event_virt(unsigned long evt,
+static int erratum_set_next_event_virt(unsigned long evt,
 					   struct clock_event_device *clk)
 {
-	fsl_a008585_set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk);
+	erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk);
 	return 0;
 }
 
-static int fsl_a008585_set_next_event_phys(unsigned long evt,
+static int erratum_set_next_event_phys(unsigned long evt,
 					   struct clock_event_device *clk)
 {
-	fsl_a008585_set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk);
+	erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk);
 	return 0;
 }
-#endif /* CONFIG_FSL_ERRATUM_A008585 */
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
 
 static int arch_timer_set_next_event_virt(unsigned long evt,
 					  struct clock_event_device *clk)
@@ -329,16 +360,16 @@ static int arch_timer_set_next_event_phy
 	return 0;
 }
 
-static void fsl_a008585_set_sne(struct clock_event_device *clk)
+static void erratum_workaround_set_sne(struct clock_event_device *clk)
 {
-#ifdef CONFIG_FSL_ERRATUM_A008585
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
 	if (!static_branch_unlikely(&arch_timer_read_ool_enabled))
 		return;
 
 	if (arch_timer_uses_ppi == VIRT_PPI)
-		clk->set_next_event = fsl_a008585_set_next_event_virt;
+		clk->set_next_event = erratum_set_next_event_virt;
 	else
-		clk->set_next_event = fsl_a008585_set_next_event_phys;
+		clk->set_next_event = erratum_set_next_event_phys;
 #endif
 }
 
@@ -371,7 +402,7 @@ static void __arch_timer_setup(unsigned
 			BUG();
 		}
 
-		fsl_a008585_set_sne(clk);
+		erratum_workaround_set_sne(clk);
 	} else {
 		clk->features |= CLOCK_EVT_FEAT_DYNIRQ;
 		clk->name = "arch_mem_timer";
@@ -600,7 +631,7 @@ static void __init arch_counter_register
 
 		clocksource_counter.archdata.vdso_direct = true;
 
-#ifdef CONFIG_FSL_ERRATUM_A008585
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
 		/*
 		 * Don't use the vdso fastpath if errata require using
 		 * the out-of-line counter accessor.
@@ -888,12 +919,15 @@ static int __init arch_timer_of_init(str
 
 	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
 
-#ifdef CONFIG_FSL_ERRATUM_A008585
-	if (fsl_a008585_enable < 0)
-		fsl_a008585_enable = of_property_read_bool(np, "fsl,erratum-a008585");
-	if (fsl_a008585_enable) {
-		static_branch_enable(&arch_timer_read_ool_enabled);
-		pr_info("Enabling workaround for FSL erratum A-008585\n");
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+	for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) {
+		if (of_property_read_bool(np, ool_workarounds[i].id)) {
+			timer_unstable_counter_workaround = &ool_workarounds[i];
+			static_branch_enable(&arch_timer_read_ool_enabled);
+			pr_info("arch_timer: Enabling workaround for %s\n",
+				timer_unstable_counter_workaround->id);
+			break;
+		}
 	}
 #endif
 

[PATCH 4.9 14/43] arm64: arch_timer: Add infrastructure for multiple erratum detection methods

[Greg Kroah-Hartman]

From: Marc Zyngier <marc.zyngier@arm.com>

commit 651bb2e9dca6e6dbad3fba5f6e6086a23575b8b5 upstream.

We're currently stuck with DT when it comes to handling errata, which
is pretty restrictive. In order to make things more flexible, let's
introduce an infrastructure that could support alternative discovery
methods. No change in functionality.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[ morse: Removed the changes to HiSilicon erratum 161010101, which isn't
  present in v4.9 ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/arch_timer.h  |    7 ++-
 drivers/clocksource/arm_arch_timer.c |   81 ++++++++++++++++++++++++++++++-----
 2 files changed, 76 insertions(+), 12 deletions(-)

--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -37,9 +37,14 @@ extern struct static_key_false arch_time
 #define needs_unstable_timer_counter_workaround()  false
 #endif
 
+enum arch_timer_erratum_match_type {
+	ate_match_dt,
+};
 
 struct arch_timer_erratum_workaround {
-	const char *id;		/* Indicate the Erratum ID */
+	enum arch_timer_erratum_match_type match_type;
+	const void *id;
+	const char *desc;
 	u32 (*read_cntp_tval_el0)(void);
 	u32 (*read_cntv_tval_el0)(void);
 	u64 (*read_cntvct_el0)(void);
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -140,13 +140,81 @@ EXPORT_SYMBOL_GPL(arch_timer_read_ool_en
 static const struct arch_timer_erratum_workaround ool_workarounds[] = {
 #ifdef CONFIG_FSL_ERRATUM_A008585
 	{
+		.match_type = ate_match_dt,
 		.id = "fsl,erratum-a008585",
+		.desc = "Freescale erratum a005858",
 		.read_cntp_tval_el0 = fsl_a008585_read_cntp_tval_el0,
 		.read_cntv_tval_el0 = fsl_a008585_read_cntv_tval_el0,
 		.read_cntvct_el0 = fsl_a008585_read_cntvct_el0,
 	},
 #endif
 };
+
+typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *,
+			       const void *);
+
+static
+bool arch_timer_check_dt_erratum(const struct arch_timer_erratum_workaround *wa,
+				 const void *arg)
+{
+	const struct device_node *np = arg;
+
+	return of_property_read_bool(np, wa->id);
+}
+
+static const struct arch_timer_erratum_workaround *
+arch_timer_iterate_errata(enum arch_timer_erratum_match_type type,
+			  ate_match_fn_t match_fn,
+			  void *arg)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) {
+		if (ool_workarounds[i].match_type != type)
+			continue;
+
+		if (match_fn(&ool_workarounds[i], arg))
+			return &ool_workarounds[i];
+	}
+
+	return NULL;
+}
+
+static
+void arch_timer_enable_workaround(const struct arch_timer_erratum_workaround *wa)
+{
+	timer_unstable_counter_workaround = wa;
+	static_branch_enable(&arch_timer_read_ool_enabled);
+}
+
+static void arch_timer_check_ool_workaround(enum arch_timer_erratum_match_type type,
+					    void *arg)
+{
+	const struct arch_timer_erratum_workaround *wa;
+	ate_match_fn_t match_fn = NULL;
+
+	if (static_branch_unlikely(&arch_timer_read_ool_enabled))
+		return;
+
+	switch (type) {
+	case ate_match_dt:
+		match_fn = arch_timer_check_dt_erratum;
+		break;
+	default:
+		WARN_ON(1);
+		return;
+	}
+
+	wa = arch_timer_iterate_errata(type, match_fn, arg);
+	if (!wa)
+		return;
+
+	arch_timer_enable_workaround(wa);
+	pr_info("Enabling global workaround for %s\n", wa->desc);
+}
+
+#else
+#define arch_timer_check_ool_workaround(t,a)		do { } while(0)
 #endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */
 
 static __always_inline
@@ -919,17 +987,8 @@ static int __init arch_timer_of_init(str
 
 	arch_timer_c3stop = !of_property_read_bool(np, "always-on");
 
-#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
-	for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) {
-		if (of_property_read_bool(np, ool_workarounds[i].id)) {
-			timer_unstable_counter_workaround = &ool_workarounds[i];
-			static_branch_enable(&arch_timer_read_ool_enabled);
-			pr_info("arch_timer: Enabling workaround for %s\n",
-				timer_unstable_counter_workaround->id);
-			break;
-		}
-	}
-#endif
+	/* Check for globally applicable workarounds */
+	arch_timer_check_ool_workaround(ate_match_dt, np);
 
 	/*
 	 * If we cannot rely on firmware initializing the timer registers then

[PATCH 4.9 15/43] arm64: arch_timer: Add erratum handler for CPU-specific capability

[Greg Kroah-Hartman]

From: Marc Zyngier <marc.zyngier@arm.com>

commit 0064030c6fd4ca6cfab42de037b2a89445beeead upstream.

Should we ever have a workaround for an erratum that is detected using
a capability and affecting a particular CPU, it'd be nice to have
a way to probe them directly.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/arch_timer.h  |    1 +
 drivers/clocksource/arm_arch_timer.c |   28 ++++++++++++++++++++++++----
 2 files changed, 25 insertions(+), 4 deletions(-)

--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -39,6 +39,7 @@ extern struct static_key_false arch_time
 
 enum arch_timer_erratum_match_type {
 	ate_match_dt,
+	ate_match_local_cap_id,
 };
 
 struct arch_timer_erratum_workaround {
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -162,6 +162,13 @@ bool arch_timer_check_dt_erratum(const s
 	return of_property_read_bool(np, wa->id);
 }
 
+static
+bool arch_timer_check_local_cap_erratum(const struct arch_timer_erratum_workaround *wa,
+					const void *arg)
+{
+	return this_cpu_has_cap((uintptr_t)wa->id);
+}
+
 static const struct arch_timer_erratum_workaround *
 arch_timer_iterate_errata(enum arch_timer_erratum_match_type type,
 			  ate_match_fn_t match_fn,
@@ -192,14 +199,16 @@ static void arch_timer_check_ool_workaro
 {
 	const struct arch_timer_erratum_workaround *wa;
 	ate_match_fn_t match_fn = NULL;
-
-	if (static_branch_unlikely(&arch_timer_read_ool_enabled))
-		return;
+	bool local = false;
 
 	switch (type) {
 	case ate_match_dt:
 		match_fn = arch_timer_check_dt_erratum;
 		break;
+	case ate_match_local_cap_id:
+		match_fn = arch_timer_check_local_cap_erratum;
+		local = true;
+		break;
 	default:
 		WARN_ON(1);
 		return;
@@ -209,8 +218,17 @@ static void arch_timer_check_ool_workaro
 	if (!wa)
 		return;
 
+	if (needs_unstable_timer_counter_workaround()) {
+		if (wa != timer_unstable_counter_workaround)
+			pr_warn("Can't enable workaround for %s (clashes with %s\n)",
+				wa->desc,
+				timer_unstable_counter_workaround->desc);
+		return;
+	}
+
 	arch_timer_enable_workaround(wa);
-	pr_info("Enabling global workaround for %s\n", wa->desc);
+	pr_info("Enabling %s workaround for %s\n",
+		local ? "local" : "global", wa->desc);
 }
 
 #else
@@ -470,6 +488,8 @@ static void __arch_timer_setup(unsigned
 			BUG();
 		}
 
+		arch_timer_check_ool_workaround(ate_match_local_cap_id, NULL);
+
 		erratum_workaround_set_sne(clk);
 	} else {
 		clk->features |= CLOCK_EVT_FEAT_DYNIRQ;

[PATCH 4.9 16/43] arm64: arch_timer: Add workaround for ARM erratum 1188873

[Greg Kroah-Hartman]

From: Marc Zyngier <marc.zyngier@arm.com>

commit 95b861a4a6d94f64d5242605569218160ebacdbe upstream.

When running on Cortex-A76, a timer access from an AArch32 EL0
task may end up with a corrupted value or register. The workaround for
this is to trap these accesses at EL1/EL2 and execute them there.

This only affects versions r0p0, r1p0 and r2p0 of the CPU.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/Kconfig                   |   12 ++++++++++++
 arch/arm64/include/asm/cpucaps.h     |    3 ++-
 arch/arm64/include/asm/cputype.h     |    2 ++
 arch/arm64/kernel/cpu_errata.c       |    8 ++++++++
 drivers/clocksource/arm_arch_timer.c |   15 +++++++++++++++
 5 files changed, 39 insertions(+), 1 deletion(-)

--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -441,6 +441,18 @@ config ARM64_ERRATUM_1024718
 
 	  If unsure, say Y.
 
+config ARM64_ERRATUM_1188873
+	bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
+	default y
+	help
+	  This option adds work arounds for ARM Cortex-A76 erratum 1188873
+
+	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause
+	  register corruption when accessing the timer registers from
+	  AArch32 userspace.
+
+	  If unsure, say Y.
+
 config CAVIUM_ERRATUM_22375
 	bool "Cavium erratum 22375, 24313"
 	default y
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -38,7 +38,8 @@
 #define ARM64_HARDEN_BRANCH_PREDICTOR		17
 #define ARM64_SSBD				18
 #define ARM64_MISMATCHED_CACHE_TYPE		19
+#define ARM64_WORKAROUND_1188873		20
 
-#define ARM64_NCAPS				20
+#define ARM64_NCAPS				21
 
 #endif /* __ASM_CPUCAPS_H */
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -85,6 +85,7 @@
 #define ARM_CPU_PART_CORTEX_A75		0xD0A
 #define ARM_CPU_PART_CORTEX_A35		0xD04
 #define ARM_CPU_PART_CORTEX_A55		0xD05
+#define ARM_CPU_PART_CORTEX_A76		0xD0B
 
 #define APM_CPU_PART_POTENZA		0x000
 
@@ -102,6 +103,7 @@
 #define MIDR_CORTEX_A75 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A75)
 #define MIDR_CORTEX_A35 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A35)
 #define MIDR_CORTEX_A55 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A55)
+#define MIDR_CORTEX_A76	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
 #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -533,6 +533,14 @@ const struct arm64_cpu_capabilities arm6
 		.matches = has_ssbd_mitigation,
 	},
 #endif
+#ifdef CONFIG_ARM64_ERRATUM_1188873
+	{
+		/* Cortex-A76 r0p0 to r2p0 */
+		.desc = "ARM erratum 1188873",
+		.capability = ARM64_WORKAROUND_1188873,
+		ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0),
+	},
+#endif
 	{
 	}
 };
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -130,6 +130,13 @@ static u64 notrace fsl_a008585_read_cntv
 }
 #endif
 
+#ifdef CONFIG_ARM64_ERRATUM_1188873
+static u64 notrace arm64_1188873_read_cntvct_el0(void)
+{
+	return read_sysreg(cntvct_el0);
+}
+#endif
+
 #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
 const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround = NULL;
 EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround);
@@ -148,6 +155,14 @@ static const struct arch_timer_erratum_w
 		.read_cntvct_el0 = fsl_a008585_read_cntvct_el0,
 	},
 #endif
+#ifdef CONFIG_ARM64_ERRATUM_1188873
+	{
+		.match_type = ate_match_local_cap_id,
+		.id = (void *)ARM64_WORKAROUND_1188873,
+		.desc = "ARM erratum 1188873",
+		.read_cntvct_el0 = arm64_1188873_read_cntvct_el0,
+	},
+#endif
 };
 
 typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *,

[PATCH 4.9 17/43] arm64: arch_timer: avoid unused function warning

[Greg Kroah-Hartman]

From: Arnd Bergmann <arnd@arndb.de>

commit 040f340134751d73bd03ee92fabb992946c55b3d upstream.

arm64_1188873_read_cntvct_el0() is protected by the correct
CONFIG_ARM64_ERRATUM_1188873 #ifdef, but the only reference to it is
also inside of an CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND section,
and causes a warning if that is disabled:

drivers/clocksource/arm_arch_timer.c:323:20: error: 'arm64_1188873_read_cntvct_el0' defined but not used [-Werror=unused-function]

Since the erratum requires that we always apply the workaround
in the timer driver, select that symbol as we do for SoC
specific errata.

Fixes: 95b861a4a6d9 ("arm64: arch_timer: Add workaround for ARM erratum 1188873")
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/Kconfig |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -444,6 +444,7 @@ config ARM64_ERRATUM_1024718
 config ARM64_ERRATUM_1188873
 	bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
 	default y
+	select ARM_ARCH_TIMER_OOL_WORKAROUND
 	help
 	  This option adds work arounds for ARM Cortex-A76 erratum 1188873
 

[PATCH 4.9 18/43] arm64: Add silicon-errata.txt entry for ARM erratum 1188873

[Greg Kroah-Hartman]

From: Marc Zyngier <marc.zyngier@arm.com>

commit e03a4e5bb7430f9294c12f02c69eb045d010e942 upstream.

Document that we actually work around ARM erratum 1188873

Fixes: 95b861a4a6d9 ("arm64: arch_timer: Add workaround for ARM erratum 1188873")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 Documentation/arm64/silicon-errata.txt |    1 +
 1 file changed, 1 insertion(+)

--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -55,6 +55,7 @@ stable kernels.
 | ARM            | Cortex-A57      | #834220         | ARM64_ERRATUM_834220        |
 | ARM            | Cortex-A72      | #853709         | N/A                         |
 | ARM            | Cortex-A55      | #1024718        | ARM64_ERRATUM_1024718       |
+| ARM            | Cortex-A76      | #1188873        | ARM64_ERRATUM_1188873       |
 | ARM            | MMU-500         | #841119,#826419 | N/A                         |
 |                |                 |                 |                             |
 | Cavium         | ThunderX ITS    | #22375, #24313  | CAVIUM_ERRATUM_22375        |

[PATCH 4.9 19/43] arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT

[Greg Kroah-Hartman]

From: Marc Zyngier <marc.zyngier@arm.com>

commit c2b5bba3967a000764e9148e6f020d776b7ecd82 upstream.

Since ARM64_ERRATUM_1188873 only affects AArch32 EL0, it makes some
sense that it should depend on COMPAT.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/Kconfig |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -444,6 +444,7 @@ config ARM64_ERRATUM_1024718
 config ARM64_ERRATUM_1188873
 	bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
 	default y
+	depends on COMPAT
 	select ARM_ARCH_TIMER_OOL_WORKAROUND
 	help
 	  This option adds work arounds for ARM Cortex-A76 erratum 1188873

[PATCH 4.9 20/43] arm64: Add part number for Neoverse N1

[Greg Kroah-Hartman]

From: Marc Zyngier <marc.zyngier@arm.com>

commit 0cf57b86859c49381addb3ce47be70aadf5fd2c0 upstream.

New CPU, new part number. You know the drill.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cputype.h |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -86,6 +86,7 @@
 #define ARM_CPU_PART_CORTEX_A35		0xD04
 #define ARM_CPU_PART_CORTEX_A55		0xD05
 #define ARM_CPU_PART_CORTEX_A76		0xD0B
+#define ARM_CPU_PART_NEOVERSE_N1	0xD0C
 
 #define APM_CPU_PART_POTENZA		0x000
 
@@ -104,6 +105,7 @@
 #define MIDR_CORTEX_A35 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A35)
 #define MIDR_CORTEX_A55 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A55)
 #define MIDR_CORTEX_A76	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76)
+#define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
 #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2)

[PATCH 4.9 21/43] arm64: Add part number for Arm Cortex-A77

[Greg Kroah-Hartman]

From: Rob Herring <robh@kernel.org>

commit 8a6b88e66233f5f1779b0a1342aa9dc030dddcd5 upstream.

Add the MIDR part number info for the Arm Cortex-A77.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201028182839.166037-1-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cputype.h |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -87,6 +87,7 @@
 #define ARM_CPU_PART_CORTEX_A55		0xD05
 #define ARM_CPU_PART_CORTEX_A76		0xD0B
 #define ARM_CPU_PART_NEOVERSE_N1	0xD0C
+#define ARM_CPU_PART_CORTEX_A77		0xD0D
 
 #define APM_CPU_PART_POTENZA		0x000
 
@@ -106,6 +107,7 @@
 #define MIDR_CORTEX_A55 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A55)
 #define MIDR_CORTEX_A76	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76)
 #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
+#define MIDR_CORTEX_A77	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
 #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2)

[PATCH 4.9 22/43] arm64: Add Neoverse-N2, Cortex-A710 CPU part definition

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

commit 2d0d656700d67239a57afaf617439143d8dac9be upstream.

Add the CPU Partnumbers for the new Arm designs.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-2-suzuki.poulose@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cputype.h |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -88,6 +88,8 @@
 #define ARM_CPU_PART_CORTEX_A76		0xD0B
 #define ARM_CPU_PART_NEOVERSE_N1	0xD0C
 #define ARM_CPU_PART_CORTEX_A77		0xD0D
+#define ARM_CPU_PART_CORTEX_A710	0xD47
+#define ARM_CPU_PART_NEOVERSE_N2	0xD49
 
 #define APM_CPU_PART_POTENZA		0x000
 
@@ -108,6 +110,8 @@
 #define MIDR_CORTEX_A76	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76)
 #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
 #define MIDR_CORTEX_A77	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77)
+#define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710)
+#define MIDR_NEOVERSE_N2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N2)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
 #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2)

[PATCH 4.9 23/43] arm64: Add Cortex-X2 CPU part definition

[Greg Kroah-Hartman]

From: Anshuman Khandual <anshuman.khandual@arm.com>

commit 72bb9dcb6c33cfac80282713c2b4f2b254cd24d1 upstream.

Add the CPU Partnumbers for the new Arm designs.

Cc: Will Deacon <will@kernel.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1642994138-25887-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cputype.h |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -89,6 +89,7 @@
 #define ARM_CPU_PART_NEOVERSE_N1	0xD0C
 #define ARM_CPU_PART_CORTEX_A77		0xD0D
 #define ARM_CPU_PART_CORTEX_A710	0xD47
+#define ARM_CPU_PART_CORTEX_X2		0xD48
 #define ARM_CPU_PART_NEOVERSE_N2	0xD49
 
 #define APM_CPU_PART_POTENZA		0x000
@@ -111,6 +112,7 @@
 #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
 #define MIDR_CORTEX_A77	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77)
 #define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710)
+#define MIDR_CORTEX_X2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X2)
 #define MIDR_NEOVERSE_N2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N2)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)



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[PATCH 4.9 23/43] arm64: Add Cortex-X2 CPU part definition

[Greg Kroah-Hartman]

From: Anshuman Khandual <anshuman.khandual@arm.com>

commit 72bb9dcb6c33cfac80282713c2b4f2b254cd24d1 upstream.

Add the CPU Partnumbers for the new Arm designs.

Cc: Will Deacon <will@kernel.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1642994138-25887-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cputype.h |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -89,6 +89,7 @@
 #define ARM_CPU_PART_NEOVERSE_N1	0xD0C
 #define ARM_CPU_PART_CORTEX_A77		0xD0D
 #define ARM_CPU_PART_CORTEX_A710	0xD47
+#define ARM_CPU_PART_CORTEX_X2		0xD48
 #define ARM_CPU_PART_NEOVERSE_N2	0xD49
 
 #define APM_CPU_PART_POTENZA		0x000
@@ -111,6 +112,7 @@
 #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
 #define MIDR_CORTEX_A77	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77)
 #define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710)
+#define MIDR_CORTEX_X2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X2)
 #define MIDR_NEOVERSE_N2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N2)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)

[PATCH 4.9 24/43] arm64: Add helper to decode register from instruction

[Greg Kroah-Hartman]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

commit 8c2dcbd2c4443bad0b4242fb62baa47b260b8f79 upstream.

Add a helper to extract the register field from a given
instruction.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/insn.h |    2 ++
 arch/arm64/kernel/insn.c      |   29 +++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

--- a/arch/arm64/include/asm/insn.h
+++ b/arch/arm64/include/asm/insn.h
@@ -332,6 +332,8 @@ bool aarch64_insn_is_branch(u32 insn);
 u64 aarch64_insn_decode_immediate(enum aarch64_insn_imm_type type, u32 insn);
 u32 aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type,
 				  u32 insn, u64 imm);
+u32 aarch64_insn_decode_register(enum aarch64_insn_register_type type,
+					 u32 insn);
 u32 aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr,
 				enum aarch64_insn_branch_type type);
 u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr,
--- a/arch/arm64/kernel/insn.c
+++ b/arch/arm64/kernel/insn.c
@@ -418,6 +418,35 @@ u32 __kprobes aarch64_insn_encode_immedi
 	return insn;
 }
 
+u32 aarch64_insn_decode_register(enum aarch64_insn_register_type type,
+					u32 insn)
+{
+	int shift;
+
+	switch (type) {
+	case AARCH64_INSN_REGTYPE_RT:
+	case AARCH64_INSN_REGTYPE_RD:
+		shift = 0;
+		break;
+	case AARCH64_INSN_REGTYPE_RN:
+		shift = 5;
+		break;
+	case AARCH64_INSN_REGTYPE_RT2:
+	case AARCH64_INSN_REGTYPE_RA:
+		shift = 10;
+		break;
+	case AARCH64_INSN_REGTYPE_RM:
+		shift = 16;
+		break;
+	default:
+		pr_err("%s: unknown register type encoding %d\n", __func__,
+		       type);
+		return 0;
+	}
+
+	return (insn >> shift) & GENMASK(4, 0);
+}
+
 static u32 aarch64_insn_encode_register(enum aarch64_insn_register_type type,
 					u32 insn,
 					enum aarch64_insn_register reg)

[PATCH 4.9 25/43] arm64: entry.S: Add ventry overflow sanity checks

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 4330e2c5c04c27bebf89d34e0bc14e6943413067 upstream.

Subsequent patches add even more code to the ventry slots.
Ensure kernels that overflow a ventry slot don't get built.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |    3 +++
 1 file changed, 3 insertions(+)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -74,6 +74,7 @@
 
 	.macro kernel_ventry, el, label, regsize = 64
 	.align 7
+.Lventry_start\@:
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 alternative_if ARM64_UNMAP_KERNEL_AT_EL0
 	.if	\el == 0
@@ -89,6 +90,7 @@ alternative_else_nop_endif
 
 	sub	sp, sp, #S_FRAME_SIZE
 	b	el\()\el\()_\label
+.org .Lventry_start\@ + 128	// Did we overflow the ventry slot?
 	.endm
 
 	.macro tramp_alias, dst, sym
@@ -935,6 +937,7 @@ __ni_sys_trace:
 	add	x30, x30, #(1b - tramp_vectors)
 	isb
 	ret
+.org 1b + 128	// Did we overflow the ventry slot?
 	.endm
 
 	.macro tramp_exit, regsize = 64

[PATCH 4.9 26/43] arm64: entry: Make the trampoline cleanup optional

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit d739da1694a0eaef0358a42b76904b611539b77b upstream.

Subsequent patches will add additional sets of vectors that use
the same tricks as the kpti vectors to reach the full-fat vectors.
The full-fat vectors contain some cleanup for kpti that is patched
in by alternatives when kpti is in use. Once there are additional
vectors, the cleanup will be needed in more cases.

But on big/little systems, the cleanup would be harmful if no
trampoline vector were in use. Instead of forcing CPUs that don't
need a trampoline vector to use one, make the trampoline cleanup
optional.

Entry at the top of the vectors will skip the cleanup. The trampoline
vectors can then skip the first instruction, triggering the cleanup
to run.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -76,16 +76,20 @@
 	.align 7
 .Lventry_start\@:
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-alternative_if ARM64_UNMAP_KERNEL_AT_EL0
 	.if	\el == 0
+	/*
+	 * This must be the first instruction of the EL0 vector entries. It is
+	 * skipped by the trampoline vectors, to trigger the cleanup.
+	 */
+	b	.Lskip_tramp_vectors_cleanup\@
 	.if	\regsize == 64
 	mrs	x30, tpidrro_el0
 	msr	tpidrro_el0, xzr
 	.else
 	mov	x30, xzr
 	.endif
+.Lskip_tramp_vectors_cleanup\@:
 	.endif
-alternative_else_nop_endif
 #endif
 
 	sub	sp, sp, #S_FRAME_SIZE
@@ -934,7 +938,7 @@ __ni_sys_trace:
 #endif
 	prfm	plil1strm, [x30, #(1b - tramp_vectors)]
 	msr	vbar_el1, x30
-	add	x30, x30, #(1b - tramp_vectors)
+	add	x30, x30, #(1b - tramp_vectors + 4)
 	isb
 	ret
 .org 1b + 128	// Did we overflow the ventry slot?

[PATCH 4.9 27/43] arm64: entry: Free up another register on kptis tramp_exit path

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 03aff3a77a58b5b52a77e00537a42090ad57b80b upstream.

Kpti stashes x30 in far_el1 while it uses x30 for all its work.

Making the vectors a per-cpu data structure will require a second
register.

Allow tramp_exit two registers before it unmaps the kernel, by
leaving x30 on the stack, and stashing x29 in far_el1.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -244,14 +244,16 @@ alternative_else_nop_endif
 	ldp	x24, x25, [sp, #16 * 12]
 	ldp	x26, x27, [sp, #16 * 13]
 	ldp	x28, x29, [sp, #16 * 14]
-	ldr	lr, [sp, #S_LR]
-	add	sp, sp, #S_FRAME_SIZE		// restore sp
 
 	.if	\el == 0
-alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0
+alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0
+	ldr	lr, [sp, #S_LR]
+	add	sp, sp, #S_FRAME_SIZE		// restore sp
+	eret
+alternative_else_nop_endif
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 	bne	4f
-	msr	far_el1, x30
+	msr	far_el1, x29
 	tramp_alias	x30, tramp_exit_native
 	br	x30
 4:
@@ -259,6 +261,8 @@ alternative_insn eret, nop, ARM64_UNMAP_
 	br	x30
 #endif
 	.else
+	ldr	lr, [sp, #S_LR]
+	add	sp, sp, #S_FRAME_SIZE		// restore sp
 	eret
 	.endif
 	.endm
@@ -947,10 +951,12 @@ __ni_sys_trace:
 	.macro tramp_exit, regsize = 64
 	adr	x30, tramp_vectors
 	msr	vbar_el1, x30
-	tramp_unmap_kernel	x30
+	ldr	lr, [sp, #S_LR]
+	tramp_unmap_kernel	x29
 	.if	\regsize == 64
-	mrs	x30, far_el1
+	mrs	x29, far_el1
 	.endif
+	add	sp, sp, #S_FRAME_SIZE		// restore sp
 	eret
 	.endm
 

[PATCH 4.9 28/43] arm64: entry: Move the trampoline data page before the text page

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit c091fb6ae059cda563b2a4d93fdbc548ef34e1d6 upstream.

The trampoline code has a data page that holds the address of the vectors,
which is unmapped when running in user-space. This ensures that with
CONFIG_RANDOMIZE_BASE, the randomised address of the kernel can't be
discovered until after the kernel has been mapped.

If the trampoline text page is extended to include multiple sets of
vectors, it will be larger than a single page, making it tricky to
find the data page without knowing the size of the trampoline text
pages, which will vary with PAGE_SIZE.

Move the data page to appear before the text page. This allows the
data page to be found without knowing the size of the trampoline text
pages. 'tramp_vectors' is used to refer to the beginning of the
.entry.tramp.text section, do that explicitly.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ removed SDEI for backport ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/fixmap.h |    2 +-
 arch/arm64/kernel/entry.S       |    7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -53,8 +53,8 @@ enum fixed_addresses {
 	FIX_TEXT_POKE0,
 
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-	FIX_ENTRY_TRAMP_DATA,
 	FIX_ENTRY_TRAMP_TEXT,
+	FIX_ENTRY_TRAMP_DATA,
 #define TRAMP_VALIAS		(__fix_to_virt(FIX_ENTRY_TRAMP_TEXT))
 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
 	__end_of_permanent_fixed_addresses,
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -918,6 +918,11 @@ __ni_sys_trace:
 	 */
 	.endm
 
+	.macro tramp_data_page	dst
+	adr	\dst, .entry.tramp.text
+	sub	\dst, \dst, PAGE_SIZE
+	.endm
+
 	.macro tramp_ventry, regsize = 64
 	.align	7
 1:
@@ -934,7 +939,7 @@ __ni_sys_trace:
 2:
 	tramp_map_kernel	x30
 #ifdef CONFIG_RANDOMIZE_BASE
-	adr	x30, tramp_vectors + PAGE_SIZE
+	tramp_data_page		x30
 	isb
 	ldr	x30, [x30]
 #else

[PATCH 4.9 29/43] arm64: entry: Allow tramp_alias to access symbols after the 4K boundary

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 6c5bf79b69f911560fbf82214c0971af6e58e682 upstream.

Systems using kpti enter and exit the kernel through a trampoline mapping
that is always mapped, even when the kernel is not. tramp_valias is a macro
to find the address of a symbol in the trampoline mapping.

Adding extra sets of vectors will expand the size of the entry.tramp.text
section to beyond 4K. tramp_valias will be unable to generate addresses
for symbols beyond 4K as it uses the 12 bit immediate of the add
instruction.

As there are now two registers available when tramp_alias is called,
use the extra register to avoid the 4K limit of the 12 bit immediate.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ Removed SDEI for backport ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -97,9 +97,12 @@
 .org .Lventry_start\@ + 128	// Did we overflow the ventry slot?
 	.endm
 
-	.macro tramp_alias, dst, sym
+	.macro tramp_alias, dst, sym, tmp
 	mov_q	\dst, TRAMP_VALIAS
-	add	\dst, \dst, #(\sym - .entry.tramp.text)
+	adr_l	\tmp, \sym
+	add	\dst, \dst, \tmp
+	adr_l	\tmp, .entry.tramp.text
+	sub	\dst, \dst, \tmp
 	.endm
 
 	// This macro corrupts x0-x3. It is the caller's duty
@@ -254,10 +257,10 @@ alternative_else_nop_endif
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 	bne	4f
 	msr	far_el1, x29
-	tramp_alias	x30, tramp_exit_native
+	tramp_alias	x30, tramp_exit_native, x29
 	br	x30
 4:
-	tramp_alias	x30, tramp_exit_compat
+	tramp_alias	x30, tramp_exit_compat, x29
 	br	x30
 #endif
 	.else

[PATCH 4.9 30/43] arm64: entry: Dont assume tramp_vectors is the start of the vectors

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit ed50da7764535f1e24432ded289974f2bf2b0c5a upstream.

The tramp_ventry macro uses tramp_vectors as the address of the vectors
when calculating which ventry in the 'full fat' vectors to branch to.

While there is one set of tramp_vectors, this will be true.
Adding multiple sets of vectors will break this assumption.

Move the generation of the vectors to a macro, and pass the start
of the vectors as an argument to tramp_ventry.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -926,7 +926,7 @@ __ni_sys_trace:
 	sub	\dst, \dst, PAGE_SIZE
 	.endm
 
-	.macro tramp_ventry, regsize = 64
+	.macro tramp_ventry, vector_start, regsize
 	.align	7
 1:
 	.if	\regsize == 64
@@ -948,9 +948,9 @@ __ni_sys_trace:
 #else
 	ldr	x30, =vectors
 #endif
-	prfm	plil1strm, [x30, #(1b - tramp_vectors)]
+	prfm	plil1strm, [x30, #(1b - \vector_start)]
 	msr	vbar_el1, x30
-	add	x30, x30, #(1b - tramp_vectors + 4)
+	add	x30, x30, #(1b - \vector_start + 4)
 	isb
 	ret
 .org 1b + 128	// Did we overflow the ventry slot?
@@ -968,19 +968,21 @@ __ni_sys_trace:
 	eret
 	.endm
 
-	.align	11
-ENTRY(tramp_vectors)
+	.macro	generate_tramp_vector
+.Lvector_start\@:
 	.space	0x400
 
-	tramp_ventry
-	tramp_ventry
-	tramp_ventry
-	tramp_ventry
-
-	tramp_ventry	32
-	tramp_ventry	32
-	tramp_ventry	32
-	tramp_ventry	32
+	.rept	4
+	tramp_ventry	.Lvector_start\@, 64
+	.endr
+	.rept	4
+	tramp_ventry	.Lvector_start\@, 32
+	.endr
+	.endm
+
+	.align	11
+ENTRY(tramp_vectors)
+	generate_tramp_vector
 END(tramp_vectors)
 
 ENTRY(tramp_exit_native)

[PATCH 4.9 31/43] arm64: entry: Move trampoline macros out of ifdefd section

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 13d7a08352a83ef2252aeb464a5e08dfc06b5dfd upstream.

The macros for building the kpti trampoline are all behind
CONFIG_UNMAP_KERNEL_AT_EL0, and in a region that outputs to the
.entry.tramp.text section.

Move the macros out so they can be used to generate other kinds of
trampoline. Only the symbols need to be guarded by
CONFIG_UNMAP_KERNEL_AT_EL0 and appear in the .entry.tramp.text section.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -896,12 +896,7 @@ __ni_sys_trace:
 
 	.popsection				// .entry.text
 
-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-/*
- * Exception vectors trampoline.
- */
-	.pushsection ".entry.tramp.text", "ax"
-
+	// Move from tramp_pg_dir to swapper_pg_dir
 	.macro tramp_map_kernel, tmp
 	mrs	\tmp, ttbr1_el1
 	sub	\tmp, \tmp, #SWAPPER_DIR_SIZE
@@ -980,6 +975,11 @@ __ni_sys_trace:
 	.endr
 	.endm
 
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+/*
+ * Exception vectors trampoline.
+ */
+	.pushsection ".entry.tramp.text", "ax"
 	.align	11
 ENTRY(tramp_vectors)
 	generate_tramp_vector

[PATCH 4.9 32/43] arm64: entry: Make the kpti trampolines kpti sequence optional

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit c47e4d04ba0f1ea17353d85d45f611277507e07a upstream.

Spectre-BHB needs to add sequences to the vectors. Having one global
set of vectors is a problem for big/little systems where the sequence
is costly on cpus that are not vulnerable.

Making the vectors per-cpu in the style of KVM's bh_harden_hyp_vecs
requires the vectors to be generated by macros.

Make the kpti re-mapping of the kernel optional, so the macros can be
used without kpti.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -921,9 +921,10 @@ __ni_sys_trace:
 	sub	\dst, \dst, PAGE_SIZE
 	.endm
 
-	.macro tramp_ventry, vector_start, regsize
+	.macro tramp_ventry, vector_start, regsize, kpti
 	.align	7
 1:
+	.if	\kpti == 1
 	.if	\regsize == 64
 	msr	tpidrro_el0, x30	// Restored in kernel_ventry
 	.endif
@@ -945,8 +946,12 @@ __ni_sys_trace:
 #endif
 	prfm	plil1strm, [x30, #(1b - \vector_start)]
 	msr	vbar_el1, x30
-	add	x30, x30, #(1b - \vector_start + 4)
 	isb
+	.else
+	ldr	x30, =vectors
+	.endif // \kpti == 1
+
+	add	x30, x30, #(1b - \vector_start + 4)
 	ret
 .org 1b + 128	// Did we overflow the ventry slot?
 	.endm
@@ -963,15 +968,15 @@ __ni_sys_trace:
 	eret
 	.endm
 
-	.macro	generate_tramp_vector
+	.macro	generate_tramp_vector,	kpti
 .Lvector_start\@:
 	.space	0x400
 
 	.rept	4
-	tramp_ventry	.Lvector_start\@, 64
+	tramp_ventry	.Lvector_start\@, 64, \kpti
 	.endr
 	.rept	4
-	tramp_ventry	.Lvector_start\@, 32
+	tramp_ventry	.Lvector_start\@, 32, \kpti
 	.endr
 	.endm
 
@@ -982,7 +987,7 @@ __ni_sys_trace:
 	.pushsection ".entry.tramp.text", "ax"
 	.align	11
 ENTRY(tramp_vectors)
-	generate_tramp_vector
+	generate_tramp_vector	kpti=1
 END(tramp_vectors)
 
 ENTRY(tramp_exit_native)

[PATCH 4.9 33/43] arm64: entry: Allow the trampoline text to occupy multiple pages

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit a9c406e6462ff14956d690de7bbe5131a5677dc9 upstream.

Adding a second set of vectors to .entry.tramp.text will make it
larger than a single 4K page.

Allow the trampoline text to occupy up to three pages by adding two
more fixmap slots. Previous changes to tramp_valias allowed it to reach
beyond a single page.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/fixmap.h   |    6 ++++--
 arch/arm64/include/asm/sections.h |    6 ++++++
 arch/arm64/kernel/entry.S         |    2 +-
 arch/arm64/kernel/vmlinux.lds.S   |    2 +-
 arch/arm64/mm/mmu.c               |   11 ++++++++---
 5 files changed, 20 insertions(+), 7 deletions(-)

--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -53,9 +53,11 @@ enum fixed_addresses {
 	FIX_TEXT_POKE0,
 
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-	FIX_ENTRY_TRAMP_TEXT,
+	FIX_ENTRY_TRAMP_TEXT3,
+	FIX_ENTRY_TRAMP_TEXT2,
+	FIX_ENTRY_TRAMP_TEXT1,
 	FIX_ENTRY_TRAMP_DATA,
-#define TRAMP_VALIAS		(__fix_to_virt(FIX_ENTRY_TRAMP_TEXT))
+#define TRAMP_VALIAS		(__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1))
 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
 	__end_of_permanent_fixed_addresses,
 
--- a/arch/arm64/include/asm/sections.h
+++ b/arch/arm64/include/asm/sections.h
@@ -26,5 +26,11 @@ extern char __hyp_text_start[], __hyp_te
 extern char __idmap_text_start[], __idmap_text_end[];
 extern char __irqentry_text_start[], __irqentry_text_end[];
 extern char __mmuoff_data_start[], __mmuoff_data_end[];
+extern char __entry_tramp_text_start[], __entry_tramp_text_end[];
+
+static inline size_t entry_tramp_text_size(void)
+{
+	return __entry_tramp_text_end - __entry_tramp_text_start;
+}
 
 #endif /* __ASM_SECTIONS_H */
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -917,7 +917,7 @@ __ni_sys_trace:
 	.endm
 
 	.macro tramp_data_page	dst
-	adr	\dst, .entry.tramp.text
+	adr_l	\dst, .entry.tramp.text
 	sub	\dst, \dst, PAGE_SIZE
 	.endm
 
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -261,7 +261,7 @@ ASSERT(__hibernate_exit_text_end - (__hi
 	<= SZ_4K, "Hibernate exit text too big or misaligned")
 #endif
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == PAGE_SIZE,
+ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) <= 3*PAGE_SIZE,
 	"Entry trampoline text too big")
 #endif
 /*
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -438,6 +438,7 @@ static void __init map_kernel_segment(pg
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 static int __init map_entry_trampoline(void)
 {
+	int i;
 	extern char __entry_tramp_text_start[];
 
 	pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
@@ -448,11 +449,15 @@ static int __init map_entry_trampoline(v
 
 	/* Map only the text into the trampoline page table */
 	memset(tramp_pg_dir, 0, PGD_SIZE);
-	__create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE,
-			     prot, pgd_pgtable_alloc, 0);
+	__create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS,
+			     entry_tramp_text_size(), prot, pgd_pgtable_alloc,
+			     0);
 
 	/* Map both the text and data into the kernel page table */
-	__set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot);
+	for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++)
+		__set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i,
+			     pa_start + i * PAGE_SIZE, prot);
+
 	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
 		extern char __entry_tramp_data_start[];
 

[PATCH 4.9 34/43] arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit aff65393fa1401e034656e349abd655cfe272de0 upstream.

kpti is an optional feature, for systems not using kpti a set of
vectors for the spectre-bhb mitigations is needed.

Add another set of vectors, __bp_harden_el1_vectors, that will be
used if a mitigation is needed and kpti is not in use.

The EL1 ventries are repeated verbatim as there is no additional
work needed for entry from EL1.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   34 +++++++++++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -924,10 +924,11 @@ __ni_sys_trace:
 	.macro tramp_ventry, vector_start, regsize, kpti
 	.align	7
 1:
-	.if	\kpti == 1
 	.if	\regsize == 64
 	msr	tpidrro_el0, x30	// Restored in kernel_ventry
 	.endif
+
+	.if	\kpti == 1
 	/*
 	 * Defend against branch aliasing attacks by pushing a dummy
 	 * entry onto the return stack and using a RET instruction to
@@ -1011,6 +1012,37 @@ __entry_tramp_data_start:
 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
 
 /*
+ * Exception vectors for spectre mitigations on entry from EL1 when
+ * kpti is not in use.
+ */
+	.macro generate_el1_vector
+.Lvector_start\@:
+	kernel_ventry	1, sync_invalid			// Synchronous EL1t
+	kernel_ventry	1, irq_invalid			// IRQ EL1t
+	kernel_ventry	1, fiq_invalid			// FIQ EL1t
+	kernel_ventry	1, error_invalid		// Error EL1t
+
+	kernel_ventry	1, sync				// Synchronous EL1h
+	kernel_ventry	1, irq				// IRQ EL1h
+	kernel_ventry	1, fiq_invalid			// FIQ EL1h
+	kernel_ventry	1, error_invalid		// Error EL1h
+
+	.rept	4
+	tramp_ventry	.Lvector_start\@, 64, kpti=0
+	.endr
+	.rept 4
+	tramp_ventry	.Lvector_start\@, 32, kpti=0
+	.endr
+	.endm
+
+	.pushsection ".entry.text", "ax"
+	.align	11
+ENTRY(__bp_harden_el1_vectors)
+	generate_el1_vector
+END(__bp_harden_el1_vectors)
+	.popsection
+
+/*
  * Special system call wrappers.
  */
 ENTRY(sys_rt_sigreturn_wrapper)

[PATCH 4.9 35/43] arm64: Move arm64_update_smccc_conduit() out of SSBD ifdef

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

arm64_update_smccc_conduit() is an alternative callback that patches
HVC/SMC. Currently the only user is SSBD. To use this for Spectre-BHB,
it needs to be moved out of the SSBD #ifdef region.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/cpu_errata.c |   44 ++++++++++++++++++++---------------------
 1 file changed, 22 insertions(+), 22 deletions(-)

--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -204,6 +204,28 @@ enable_smccc_arch_workaround_1(const str
 }
 #endif	/* CONFIG_HARDEN_BRANCH_PREDICTOR */
 
+void __init arm64_update_smccc_conduit(struct alt_instr *alt,
+				       __le32 *origptr, __le32 *updptr,
+				       int nr_inst)
+{
+	u32 insn;
+
+	BUG_ON(nr_inst != 1);
+
+	switch (psci_ops.conduit) {
+	case PSCI_CONDUIT_HVC:
+		insn = aarch64_insn_get_hvc_value();
+		break;
+	case PSCI_CONDUIT_SMC:
+		insn = aarch64_insn_get_smc_value();
+		break;
+	default:
+		return;
+	}
+
+	*updptr = cpu_to_le32(insn);
+}
+
 #ifdef CONFIG_ARM64_SSBD
 DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required);
 
@@ -239,28 +261,6 @@ static int __init ssbd_cfg(char *buf)
 }
 early_param("ssbd", ssbd_cfg);
 
-void __init arm64_update_smccc_conduit(struct alt_instr *alt,
-				       __le32 *origptr, __le32 *updptr,
-				       int nr_inst)
-{
-	u32 insn;
-
-	BUG_ON(nr_inst != 1);
-
-	switch (psci_ops.conduit) {
-	case PSCI_CONDUIT_HVC:
-		insn = aarch64_insn_get_hvc_value();
-		break;
-	case PSCI_CONDUIT_SMC:
-		insn = aarch64_insn_get_smc_value();
-		break;
-	default:
-		return;
-	}
-
-	*updptr = cpu_to_le32(insn);
-}
-
 void __init arm64_enable_wa2_handling(struct alt_instr *alt,
 				      __le32 *origptr, __le32 *updptr,
 				      int nr_inst)

[PATCH 4.9 36/43] arm64: entry: Add vectors that have the bhb mitigation sequences

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit ba2689234be92024e5635d30fe744f4853ad97db upstream.

Some CPUs affected by Spectre-BHB need a sequence of branches, or a
firmware call to be run before any indirect branch. This needs to go
in the vectors. No CPU needs both.

While this can be patched in, it would run on all CPUs as there is a
single set of vectors. If only one part of a big/little combination is
affected, the unaffected CPUs have to run the mitigation too.

Create extra vectors that include the sequence. Subsequent patches will
allow affected CPUs to select this set of vectors. Later patches will
modify the loop count to match what the CPU requires.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/assembler.h |   25 +++++++++++++++++
 arch/arm64/include/asm/vectors.h   |   34 +++++++++++++++++++++++
 arch/arm64/kernel/entry.S          |   53 ++++++++++++++++++++++++++++++-------
 include/linux/arm-smccc.h          |    7 ++++
 4 files changed, 110 insertions(+), 9 deletions(-)
 create mode 100644 arch/arm64/include/asm/vectors.h

--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -494,4 +494,29 @@ alternative_endif
 .Ldone\@:
 	.endm
 
+	.macro __mitigate_spectre_bhb_loop      tmp
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+	mov	\tmp, #32
+.Lspectre_bhb_loop\@:
+	b	. + 4
+	subs	\tmp, \tmp, #1
+	b.ne	.Lspectre_bhb_loop\@
+	dsb	nsh
+	isb
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+	.endm
+
+	/* Save/restores x0-x3 to the stack */
+	.macro __mitigate_spectre_bhb_fw
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+	stp	x0, x1, [sp, #-16]!
+	stp	x2, x3, [sp, #-16]!
+	mov	w0, #ARM_SMCCC_ARCH_WORKAROUND_3
+alternative_cb	arm64_update_smccc_conduit
+	nop					// Patched to SMC/HVC #0
+alternative_cb_end
+	ldp	x2, x3, [sp], #16
+	ldp	x0, x1, [sp], #16
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+	.endm
 #endif	/* __ASM_ASSEMBLER_H */
--- /dev/null
+++ b/arch/arm64/include/asm/vectors.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 ARM Ltd.
+ */
+#ifndef __ASM_VECTORS_H
+#define __ASM_VECTORS_H
+
+/*
+ * Note: the order of this enum corresponds to two arrays in entry.S:
+ * tramp_vecs and __bp_harden_el1_vectors. By default the canonical
+ * 'full fat' vectors are used directly.
+ */
+enum arm64_bp_harden_el1_vectors {
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+	/*
+	 * Perform the BHB loop mitigation, before branching to the canonical
+	 * vectors.
+	 */
+	EL1_VECTOR_BHB_LOOP,
+
+	/*
+	 * Make the SMC call for firmware mitigation, before branching to the
+	 * canonical vectors.
+	 */
+	EL1_VECTOR_BHB_FW,
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+
+	/*
+	 * Remap the kernel before branching to the canonical vectors.
+	 */
+	EL1_VECTOR_KPTI,
+};
+
+#endif /* __ASM_VECTORS_H */
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -921,13 +921,26 @@ __ni_sys_trace:
 	sub	\dst, \dst, PAGE_SIZE
 	.endm
 
-	.macro tramp_ventry, vector_start, regsize, kpti
+
+#define BHB_MITIGATION_NONE	0
+#define BHB_MITIGATION_LOOP	1
+#define BHB_MITIGATION_FW	2
+
+	.macro tramp_ventry, vector_start, regsize, kpti, bhb
 	.align	7
 1:
 	.if	\regsize == 64
 	msr	tpidrro_el0, x30	// Restored in kernel_ventry
 	.endif
 
+	.if	\bhb == BHB_MITIGATION_LOOP
+	/*
+	 * This sequence must appear before the first indirect branch. i.e. the
+	 * ret out of tramp_ventry. It appears here because x30 is free.
+	 */
+	__mitigate_spectre_bhb_loop	x30
+	.endif // \bhb == BHB_MITIGATION_LOOP
+
 	.if	\kpti == 1
 	/*
 	 * Defend against branch aliasing attacks by pushing a dummy
@@ -952,6 +965,15 @@ __ni_sys_trace:
 	ldr	x30, =vectors
 	.endif // \kpti == 1
 
+	.if	\bhb == BHB_MITIGATION_FW
+	/*
+	 * The firmware sequence must appear before the first indirect branch.
+	 * i.e. the ret out of tramp_ventry. But it also needs the stack to be
+	 * mapped to save/restore the registers the SMC clobbers.
+	 */
+	__mitigate_spectre_bhb_fw
+	.endif // \bhb == BHB_MITIGATION_FW
+
 	add	x30, x30, #(1b - \vector_start + 4)
 	ret
 .org 1b + 128	// Did we overflow the ventry slot?
@@ -959,6 +981,9 @@ __ni_sys_trace:
 
 	.macro tramp_exit, regsize = 64
 	adr	x30, tramp_vectors
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+	add	x30, x30, SZ_4K
+#endif
 	msr	vbar_el1, x30
 	ldr	lr, [sp, #S_LR]
 	tramp_unmap_kernel	x29
@@ -969,26 +994,32 @@ __ni_sys_trace:
 	eret
 	.endm
 
-	.macro	generate_tramp_vector,	kpti
+	.macro	generate_tramp_vector,	kpti, bhb
 .Lvector_start\@:
 	.space	0x400
 
 	.rept	4
-	tramp_ventry	.Lvector_start\@, 64, \kpti
+	tramp_ventry	.Lvector_start\@, 64, \kpti, \bhb
 	.endr
 	.rept	4
-	tramp_ventry	.Lvector_start\@, 32, \kpti
+	tramp_ventry	.Lvector_start\@, 32, \kpti, \bhb
 	.endr
 	.endm
 
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 /*
  * Exception vectors trampoline.
+ * The order must match __bp_harden_el1_vectors and the
+ * arm64_bp_harden_el1_vectors enum.
  */
 	.pushsection ".entry.tramp.text", "ax"
 	.align	11
 ENTRY(tramp_vectors)
-	generate_tramp_vector	kpti=1
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_LOOP
+	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_FW
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_NONE
 END(tramp_vectors)
 
 ENTRY(tramp_exit_native)
@@ -1015,7 +1046,7 @@ __entry_tramp_data_start:
  * Exception vectors for spectre mitigations on entry from EL1 when
  * kpti is not in use.
  */
-	.macro generate_el1_vector
+	.macro generate_el1_vector, bhb
 .Lvector_start\@:
 	kernel_ventry	1, sync_invalid			// Synchronous EL1t
 	kernel_ventry	1, irq_invalid			// IRQ EL1t
@@ -1028,17 +1059,21 @@ __entry_tramp_data_start:
 	kernel_ventry	1, error_invalid		// Error EL1h
 
 	.rept	4
-	tramp_ventry	.Lvector_start\@, 64, kpti=0
+	tramp_ventry	.Lvector_start\@, 64, 0, \bhb
 	.endr
 	.rept 4
-	tramp_ventry	.Lvector_start\@, 32, kpti=0
+	tramp_ventry	.Lvector_start\@, 32, 0, \bhb
 	.endr
 	.endm
 
+/* The order must match tramp_vecs and the arm64_bp_harden_el1_vectors enum. */
 	.pushsection ".entry.text", "ax"
 	.align	11
 ENTRY(__bp_harden_el1_vectors)
-	generate_el1_vector
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+	generate_el1_vector	bhb=BHB_MITIGATION_LOOP
+	generate_el1_vector	bhb=BHB_MITIGATION_FW
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
 END(__bp_harden_el1_vectors)
 	.popsection
 
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -85,6 +85,13 @@
 			   ARM_SMCCC_SMC_32,				\
 			   0, 0x7fff)
 
+#define ARM_SMCCC_ARCH_WORKAROUND_3					\
+	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
+			   ARM_SMCCC_SMC_32,				\
+			   0, 0x3fff)
+
+#define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED	1
+
 #ifndef __ASSEMBLY__
 
 #include <linux/linkage.h>

[PATCH 4.9 37/43] arm64: entry: Add macro for reading symbol addresses from the trampoline

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit b28a8eebe81c186fdb1a0078263b30576c8e1f42 upstream.

The trampoline code needs to use the address of symbols in the wider
kernel, e.g. vectors. PC-relative addressing wouldn't work as the
trampoline code doesn't run at the address the linker expected.

tramp_ventry uses a literal pool, unless CONFIG_RANDOMIZE_BASE is
set, in which case it uses the data page as a literal pool because
the data page can be unmapped when running in user-space, which is
required for CPUs vulnerable to meltdown.

Pull this logic out as a macro, instead of adding a third copy
of it.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ Removed SDEI for stable backport ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/kernel/entry.S |   22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -921,6 +921,15 @@ __ni_sys_trace:
 	sub	\dst, \dst, PAGE_SIZE
 	.endm
 
+	.macro tramp_data_read_var	dst, var
+#ifdef CONFIG_RANDOMIZE_BASE
+	tramp_data_page		\dst
+	add	\dst, \dst, #:lo12:__entry_tramp_data_\var
+	ldr	\dst, [\dst]
+#else
+	ldr	\dst, =\var
+#endif
+	.endm
 
 #define BHB_MITIGATION_NONE	0
 #define BHB_MITIGATION_LOOP	1
@@ -951,13 +960,7 @@ __ni_sys_trace:
 	b	.
 2:
 	tramp_map_kernel	x30
-#ifdef CONFIG_RANDOMIZE_BASE
-	tramp_data_page		x30
-	isb
-	ldr	x30, [x30]
-#else
-	ldr	x30, =vectors
-#endif
+	tramp_data_read_var	x30, vectors
 	prfm	plil1strm, [x30, #(1b - \vector_start)]
 	msr	vbar_el1, x30
 	isb
@@ -1037,7 +1040,12 @@ END(tramp_exit_compat)
 	.align PAGE_SHIFT
 	.globl	__entry_tramp_data_start
 __entry_tramp_data_start:
+__entry_tramp_data_vectors:
 	.quad	vectors
+#ifdef CONFIG_ARM_SDE_INTERFACE
+__entry_tramp_data___sdei_asm_trampoline_next_handler:
+	.quad	__sdei_asm_handler
+#endif /* CONFIG_ARM_SDE_INTERFACE */
 	.popsection				// .rodata
 #endif /* CONFIG_RANDOMIZE_BASE */
 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */

[PATCH 4.9 38/43] arm64: Add percpu vectors for EL1

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit bd09128d16fac3c34b80bd6a29088ac632e8ce09 upstream.

The Spectre-BHB workaround adds a firmware call to the vectors. This
is needed on some CPUs, but not others. To avoid the unaffected CPU in
a big/little pair from making the firmware call, create per cpu vectors.

The per-cpu vectors only apply when returning from EL0.

Systems using KPTI can use the canonical 'full-fat' vectors directly at
EL1, the trampoline exit code will switch to this_cpu_vector on exit to
EL0. Systems not using KPTI should always use this_cpu_vector.

this_cpu_vector will point at a vector in tramp_vecs or
__bp_harden_el1_vectors, depending on whether KPTI is in use.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/mmu.h     |    2 +-
 arch/arm64/include/asm/vectors.h |   27 +++++++++++++++++++++++++++
 arch/arm64/kernel/cpufeature.c   |   11 +++++++++++
 arch/arm64/kernel/entry.S        |   16 ++++++++++------
 arch/arm64/kvm/hyp/switch.c      |    9 ++++++---
 5 files changed, 55 insertions(+), 10 deletions(-)

--- a/arch/arm64/include/asm/mmu.h
+++ b/arch/arm64/include/asm/mmu.h
@@ -34,7 +34,7 @@ typedef struct {
  */
 #define ASID(mm)	((mm)->context.id.counter & 0xffff)
 
-static inline bool arm64_kernel_unmapped_at_el0(void)
+static __always_inline bool arm64_kernel_unmapped_at_el0(void)
 {
 	return IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) &&
 	       cpus_have_const_cap(ARM64_UNMAP_KERNEL_AT_EL0);
--- a/arch/arm64/include/asm/vectors.h
+++ b/arch/arm64/include/asm/vectors.h
@@ -5,6 +5,15 @@
 #ifndef __ASM_VECTORS_H
 #define __ASM_VECTORS_H
 
+#include <linux/bug.h>
+#include <linux/percpu.h>
+
+#include <asm/fixmap.h>
+
+extern char vectors[];
+extern char tramp_vectors[];
+extern char __bp_harden_el1_vectors[];
+
 /*
  * Note: the order of this enum corresponds to two arrays in entry.S:
  * tramp_vecs and __bp_harden_el1_vectors. By default the canonical
@@ -31,4 +40,22 @@ enum arm64_bp_harden_el1_vectors {
 	EL1_VECTOR_KPTI,
 };
 
+/* The vectors to use on return from EL0. e.g. to remap the kernel */
+DECLARE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector);
+
+#ifndef CONFIG_UNMAP_KERNEL_AT_EL0
+#define TRAMP_VALIAS	0
+#endif
+
+static inline const char *
+arm64_get_bp_hardening_vector(enum arm64_bp_harden_el1_vectors slot)
+{
+	if (arm64_kernel_unmapped_at_el0())
+		return (char *)TRAMP_VALIAS + SZ_2K * slot;
+
+	WARN_ON_ONCE(slot == EL1_VECTOR_KPTI);
+
+	return __bp_harden_el1_vectors + SZ_2K * slot;
+}
+
 #endif /* __ASM_VECTORS_H */
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -20,15 +20,18 @@
 
 #include <linux/bsearch.h>
 #include <linux/cpumask.h>
+#include <linux/percpu.h>
 #include <linux/sort.h>
 #include <linux/stop_machine.h>
 #include <linux/types.h>
+
 #include <asm/cpu.h>
 #include <asm/cpufeature.h>
 #include <asm/cpu_ops.h>
 #include <asm/mmu_context.h>
 #include <asm/processor.h>
 #include <asm/sysreg.h>
+#include <asm/vectors.h>
 #include <asm/virt.h>
 
 unsigned long elf_hwcap __read_mostly;
@@ -49,6 +52,8 @@ unsigned int compat_elf_hwcap2 __read_mo
 DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
 EXPORT_SYMBOL(cpu_hwcaps);
 
+DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
+
 DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS);
 EXPORT_SYMBOL(cpu_hwcap_keys);
 
@@ -821,6 +826,12 @@ kpti_install_ng_mappings(const struct ar
 	static bool kpti_applied = false;
 	int cpu = smp_processor_id();
 
+	if (__this_cpu_read(this_cpu_vector) == vectors) {
+		const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
+
+		__this_cpu_write(this_cpu_vector, v);
+	}
+
 	if (kpti_applied)
 		return;
 
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -75,7 +75,6 @@
 	.macro kernel_ventry, el, label, regsize = 64
 	.align 7
 .Lventry_start\@:
-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 	.if	\el == 0
 	/*
 	 * This must be the first instruction of the EL0 vector entries. It is
@@ -90,7 +89,6 @@
 	.endif
 .Lskip_tramp_vectors_cleanup\@:
 	.endif
-#endif
 
 	sub	sp, sp, #S_FRAME_SIZE
 	b	el\()\el\()_\label
@@ -983,10 +981,14 @@ __ni_sys_trace:
 	.endm
 
 	.macro tramp_exit, regsize = 64
-	adr	x30, tramp_vectors
-#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
-	add	x30, x30, SZ_4K
-#endif
+	tramp_data_read_var	x30, this_cpu_vector
+alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
+	mrs	x29, tpidr_el1
+alternative_else
+	mrs	x29, tpidr_el2
+alternative_endif
+	ldr	x30, [x30, x29]
+
 	msr	vbar_el1, x30
 	ldr	lr, [sp, #S_LR]
 	tramp_unmap_kernel	x29
@@ -1046,6 +1048,8 @@ __entry_tramp_data_vectors:
 __entry_tramp_data___sdei_asm_trampoline_next_handler:
 	.quad	__sdei_asm_handler
 #endif /* CONFIG_ARM_SDE_INTERFACE */
+__entry_tramp_data_this_cpu_vector:
+	.quad	this_cpu_vector
 	.popsection				// .rodata
 #endif /* CONFIG_RANDOMIZE_BASE */
 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -26,7 +26,7 @@
 #include <asm/kvm_emulate.h>
 #include <asm/kvm_hyp.h>
 #include <asm/uaccess.h>
-
+#include <asm/vectors.h>
 extern struct exception_table_entry __start___kvm_ex_table;
 extern struct exception_table_entry __stop___kvm_ex_table;
 
@@ -107,11 +107,14 @@ static void __hyp_text __activate_traps(
 
 static void __hyp_text __deactivate_traps_vhe(void)
 {
-	extern char vectors[];	/* kernel exception vectors */
+	const char *host_vectors = vectors;
 
 	write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
 	write_sysreg(CPACR_EL1_FPEN, cpacr_el1);
-	write_sysreg(vectors, vbar_el1);
+
+	if (!arm64_kernel_unmapped_at_el0())
+		host_vectors = __this_cpu_read(this_cpu_vector);
+	write_sysreg(host_vectors, vbar_el1);
 }
 
 static void __hyp_text __deactivate_traps_nvhe(void)

[PATCH 4.9 39/43] KVM: arm64: Add templates for BHB mitigation sequences

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

KVM writes the Spectre-v2 mitigation template at the beginning of each
vector when a CPU requires a specific sequence to run.

Because the template is copied, it can not be modified by the alternatives
at runtime. As the KVM template code is intertwined with the bp-hardening
callbacks, all templates must have a bp-hardening callback.

Add templates for calling ARCH_WORKAROUND_3 and one for each value of K
in the brancy-loop. Identify these sequences by a new parameter
template_start, and add a copy of install_bp_hardening_cb() that is able to
install them.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpucaps.h |    3 +
 arch/arm64/include/asm/kvm_mmu.h |    2 -
 arch/arm64/include/asm/mmu.h     |    6 +++
 arch/arm64/kernel/bpi.S          |   50 +++++++++++++++++++++++++++
 arch/arm64/kernel/cpu_errata.c   |   71 +++++++++++++++++++++++++++++++++++++--
 5 files changed, 128 insertions(+), 4 deletions(-)

--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -39,7 +39,8 @@
 #define ARM64_SSBD				18
 #define ARM64_MISMATCHED_CACHE_TYPE		19
 #define ARM64_WORKAROUND_1188873		20
+#define ARM64_SPECTRE_BHB			21
 
-#define ARM64_NCAPS				21
+#define ARM64_NCAPS				22
 
 #endif /* __ASM_CPUCAPS_H */
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -362,7 +362,7 @@ static inline void *kvm_get_hyp_vector(v
 	struct bp_hardening_data *data = arm64_get_bp_hardening_data();
 	void *vect = kvm_ksym_ref(__kvm_hyp_vector);
 
-	if (data->fn) {
+	if (data->template_start) {
 		vect = __bp_harden_hyp_vecs_start +
 		       data->hyp_vectors_slot * SZ_2K;
 
--- a/arch/arm64/include/asm/mmu.h
+++ b/arch/arm64/include/asm/mmu.h
@@ -45,6 +45,12 @@ typedef void (*bp_hardening_cb_t)(void);
 struct bp_hardening_data {
 	int			hyp_vectors_slot;
 	bp_hardening_cb_t	fn;
+
+	/*
+	 * template_start is only used by the BHB mitigation to identify the
+	 * hyp_vectors_slot sequence.
+	 */
+	const char *template_start;
 };
 
 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
--- a/arch/arm64/kernel/bpi.S
+++ b/arch/arm64/kernel/bpi.S
@@ -73,3 +73,53 @@ ENTRY(__smccc_workaround_1_smc_end)
 ENTRY(__smccc_workaround_1_hvc_start)
 	smccc_workaround_1	hvc
 ENTRY(__smccc_workaround_1_hvc_end)
+
+ENTRY(__smccc_workaround_3_smc_start)
+	sub     sp, sp, #(8 * 4)
+	stp     x2, x3, [sp, #(8 * 0)]
+	stp     x0, x1, [sp, #(8 * 2)]
+	mov     w0, #ARM_SMCCC_ARCH_WORKAROUND_3
+	smc     #0
+	ldp     x2, x3, [sp, #(8 * 0)]
+	ldp     x0, x1, [sp, #(8 * 2)]
+	add     sp, sp, #(8 * 4)
+ENTRY(__smccc_workaround_3_smc_end)
+
+ENTRY(__spectre_bhb_loop_k8_start)
+	sub     sp, sp, #(8 * 2)
+	stp     x0, x1, [sp, #(8 * 0)]
+	mov     x0, #8
+2:	b       . + 4
+	subs    x0, x0, #1
+	b.ne    2b
+	dsb     nsh
+	isb
+	ldp     x0, x1, [sp, #(8 * 0)]
+	add     sp, sp, #(8 * 2)
+ENTRY(__spectre_bhb_loop_k8_end)
+
+ENTRY(__spectre_bhb_loop_k24_start)
+	sub     sp, sp, #(8 * 2)
+	stp     x0, x1, [sp, #(8 * 0)]
+	mov     x0, #24
+2:	b       . + 4
+	subs    x0, x0, #1
+	b.ne    2b
+	dsb     nsh
+	isb
+	ldp     x0, x1, [sp, #(8 * 0)]
+	add     sp, sp, #(8 * 2)
+ENTRY(__spectre_bhb_loop_k24_end)
+
+ENTRY(__spectre_bhb_loop_k32_start)
+	sub     sp, sp, #(8 * 2)
+	stp     x0, x1, [sp, #(8 * 0)]
+	mov     x0, #32
+2:	b       . + 4
+	subs    x0, x0, #1
+	b.ne    2b
+	dsb     nsh
+	isb
+	ldp     x0, x1, [sp, #(8 * 0)]
+	add     sp, sp, #(8 * 2)
+ENTRY(__spectre_bhb_loop_k32_end)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -74,6 +74,14 @@ extern char __smccc_workaround_1_smc_sta
 extern char __smccc_workaround_1_smc_end[];
 extern char __smccc_workaround_1_hvc_start[];
 extern char __smccc_workaround_1_hvc_end[];
+extern char __smccc_workaround_3_smc_start[];
+extern char __smccc_workaround_3_smc_end[];
+extern char __spectre_bhb_loop_k8_start[];
+extern char __spectre_bhb_loop_k8_end[];
+extern char __spectre_bhb_loop_k24_start[];
+extern char __spectre_bhb_loop_k24_end[];
+extern char __spectre_bhb_loop_k32_start[];
+extern char __spectre_bhb_loop_k32_end[];
 
 static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
 				const char *hyp_vecs_end)
@@ -87,12 +95,14 @@ static void __copy_hyp_vect_bpi(int slot
 	flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K);
 }
 
+static DEFINE_SPINLOCK(bp_lock);
+static int last_slot = -1;
+
 static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
 				      const char *hyp_vecs_start,
 				      const char *hyp_vecs_end)
 {
-	static int last_slot = -1;
-	static DEFINE_SPINLOCK(bp_lock);
+
 	int cpu, slot = -1;
 
 	spin_lock(&bp_lock);
@@ -113,6 +123,7 @@ static void __install_bp_hardening_cb(bp
 
 	__this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
 	__this_cpu_write(bp_hardening_data.fn, fn);
+	__this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start);
 	spin_unlock(&bp_lock);
 }
 #else
@@ -544,3 +555,59 @@ const struct arm64_cpu_capabilities arm6
 	{
 	}
 };
+
+#ifdef CONFIG_KVM
+static const char *kvm_bhb_get_vecs_end(const char *start)
+{
+	if (start == __smccc_workaround_3_smc_start)
+		return __smccc_workaround_3_smc_end;
+	else if (start == __spectre_bhb_loop_k8_start)
+		return __spectre_bhb_loop_k8_end;
+	else if (start == __spectre_bhb_loop_k24_start)
+		return __spectre_bhb_loop_k24_end;
+	else if (start == __spectre_bhb_loop_k32_start)
+		return __spectre_bhb_loop_k32_end;
+
+	return NULL;
+}
+
+void kvm_setup_bhb_slot(const char *hyp_vecs_start)
+{
+	int cpu, slot = -1;
+	const char *hyp_vecs_end;
+
+	if (!IS_ENABLED(CONFIG_KVM) || !is_hyp_mode_available())
+		return;
+
+	hyp_vecs_end = kvm_bhb_get_vecs_end(hyp_vecs_start);
+	if (WARN_ON_ONCE(!hyp_vecs_start || !hyp_vecs_end))
+		return;
+
+	spin_lock(&bp_lock);
+	for_each_possible_cpu(cpu) {
+		if (per_cpu(bp_hardening_data.template_start, cpu) == hyp_vecs_start) {
+			slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu);
+			break;
+		}
+	}
+
+	if (slot == -1) {
+		last_slot++;
+		BUG_ON(((__bp_harden_hyp_vecs_end - __bp_harden_hyp_vecs_start)
+			/ SZ_2K) <= last_slot);
+		slot = last_slot;
+		__copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end);
+	}
+
+	__this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
+	__this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start);
+	spin_unlock(&bp_lock);
+}
+#else
+#define __smccc_workaround_3_smc_start NULL
+#define __spectre_bhb_loop_k8_start NULL
+#define __spectre_bhb_loop_k24_start NULL
+#define __spectre_bhb_loop_k32_start NULL
+
+void kvm_setup_bhb_slot(const char *hyp_vecs_start) { };
+#endif

[PATCH 4.9 40/43] arm64: Mitigate spectre style branch history side channels

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 558c303c9734af5a813739cd284879227f7297d2 upstream.

Speculation attacks against some high-performance processors can
make use of branch history to influence future speculation.
When taking an exception from user-space, a sequence of branches
or a firmware call overwrites or invalidates the branch history.

The sequence of branches is added to the vectors, and should appear
before the first indirect branch. For systems using KPTI the sequence
is added to the kpti trampoline where it has a free register as the exit
from the trampoline is via a 'ret'. For systems not using KPTI, the same
register tricks are used to free up a register in the vectors.

For the firmware call, arch-workaround-3 clobbers 4 registers, so
there is no choice but to save them to the EL1 stack. This only happens
for entry from EL0, so if we take an exception due to the stack access,
it will not become re-entrant.

For KVM, the existing branch-predictor-hardening vectors are used.
When a spectre version of these vectors is in use, the firmware call
is sufficient to mitigate against Spectre-BHB. For the non-spectre
versions, the sequence of branches is added to the indirect vector.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: <stable@kernel.org> # <v5.17.x 72bb9dcb6c33c arm64: Add Cortex-X2 CPU part definition
Cc: <stable@kernel.org> # <v5.16.x 2d0d656700d67 arm64: Add Neoverse-N2, Cortex-A710 CPU part definition
Cc: <stable@kernel.org> # <v5.10.x 8a6b88e66233f arm64: Add part number for Arm Cortex-A77
[ modified for stable, moved code to cpu_errata.c removed bitmap of
  mitigations, use kvm template infrastructure, added is_spectrev2_safe()
  helper ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/Kconfig                  |   10 +
 arch/arm64/include/asm/assembler.h  |    4 
 arch/arm64/include/asm/cpufeature.h |   27 +++
 arch/arm64/include/asm/cputype.h    |    8 +
 arch/arm64/include/asm/sysreg.h     |    1 
 arch/arm64/include/asm/vectors.h    |    6 
 arch/arm64/kernel/cpu_errata.c      |  284 +++++++++++++++++++++++++++++++++++-
 arch/arm64/kvm/hyp/hyp-entry.S      |    4 
 8 files changed, 341 insertions(+), 3 deletions(-)

--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -799,6 +799,16 @@ config ARM64_SSBD
 
 	  If unsure, say Y.
 
+config MITIGATE_SPECTRE_BRANCH_HISTORY
+	bool "Mitigate Spectre style attacks against branch history" if EXPERT
+	default y
+	depends on HARDEN_BRANCH_PREDICTOR || !KVM
+	help
+	  Speculation attacks against some high-performance processors can
+	  make use of branch history to influence future speculation.
+	  When taking an exception from user-space, a sequence of branches
+	  or a firmware call overwrites the branch history.
+
 menuconfig ARMV8_DEPRECATED
 	bool "Emulate deprecated/obsolete ARMv8 instructions"
 	depends on COMPAT
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -496,7 +496,9 @@ alternative_endif
 
 	.macro __mitigate_spectre_bhb_loop      tmp
 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
-	mov	\tmp, #32
+alternative_cb  spectre_bhb_patch_loop_iter
+	mov	\tmp, #32		// Patched to correct the immediate
+alternative_cb_end
 .Lspectre_bhb_loop\@:
 	b	. + 4
 	subs	\tmp, \tmp, #1
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -372,6 +372,21 @@ static inline bool cpu_supports_mixed_en
 	return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
 }
 
+static inline bool supports_csv2p3(int scope)
+{
+	u64 pfr0;
+	u8 csv2_val;
+
+	if (scope == SCOPE_LOCAL_CPU)
+		pfr0 = read_sysreg_s(SYS_ID_AA64PFR0_EL1);
+	else
+		pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1);
+
+	csv2_val = cpuid_feature_extract_unsigned_field(pfr0,
+							ID_AA64PFR0_CSV2_SHIFT);
+	return csv2_val == 3;
+}
+
 static inline bool system_supports_32bit_el0(void)
 {
 	return cpus_have_const_cap(ARM64_HAS_32BIT_EL0);
@@ -404,6 +419,18 @@ void arm64_set_ssbd_mitigation(bool stat
 static inline void arm64_set_ssbd_mitigation(bool state) {}
 #endif
 
+/* Watch out, ordering is important here. */
+enum mitigation_state {
+	SPECTRE_UNAFFECTED,
+	SPECTRE_MITIGATED,
+	SPECTRE_VULNERABLE,
+};
+
+enum mitigation_state arm64_get_spectre_bhb_state(void);
+bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, int scope);
+u8 spectre_bhb_loop_affected(int scope);
+void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry);
+
 #endif /* __ASSEMBLY__ */
 
 #endif
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -88,9 +88,13 @@
 #define ARM_CPU_PART_CORTEX_A76		0xD0B
 #define ARM_CPU_PART_NEOVERSE_N1	0xD0C
 #define ARM_CPU_PART_CORTEX_A77		0xD0D
+#define ARM_CPU_PART_NEOVERSE_V1	0xD40
+#define ARM_CPU_PART_CORTEX_A78		0xD41
+#define ARM_CPU_PART_CORTEX_X1		0xD44
 #define ARM_CPU_PART_CORTEX_A710	0xD47
 #define ARM_CPU_PART_CORTEX_X2		0xD48
 #define ARM_CPU_PART_NEOVERSE_N2	0xD49
+#define ARM_CPU_PART_CORTEX_A78C	0xD4B
 
 #define APM_CPU_PART_POTENZA		0x000
 
@@ -111,9 +115,13 @@
 #define MIDR_CORTEX_A76	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76)
 #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
 #define MIDR_CORTEX_A77	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77)
+#define MIDR_NEOVERSE_V1	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_V1)
+#define MIDR_CORTEX_A78	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78)
+#define MIDR_CORTEX_X1	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X1)
 #define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710)
 #define MIDR_CORTEX_X2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X2)
 #define MIDR_NEOVERSE_N2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N2)
+#define MIDR_CORTEX_A78C	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78C)
 #define MIDR_THUNDERX	MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
 #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
 #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2)
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -211,6 +211,7 @@
 #define ID_AA64MMFR0_TGRAN16_SUPPORTED	0x1
 
 /* id_aa64mmfr1 */
+#define ID_AA64MMFR1_ECBHB_SHIFT	60
 #define ID_AA64MMFR1_PAN_SHIFT		20
 #define ID_AA64MMFR1_LOR_SHIFT		16
 #define ID_AA64MMFR1_HPD_SHIFT		12
--- a/arch/arm64/include/asm/vectors.h
+++ b/arch/arm64/include/asm/vectors.h
@@ -9,6 +9,7 @@
 #include <linux/percpu.h>
 
 #include <asm/fixmap.h>
+#include <asm/mmu.h>
 
 extern char vectors[];
 extern char tramp_vectors[];
@@ -40,6 +41,11 @@ enum arm64_bp_harden_el1_vectors {
 	EL1_VECTOR_KPTI,
 };
 
+#ifndef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+#define EL1_VECTOR_BHB_LOOP		-1
+#define EL1_VECTOR_BHB_FW		-1
+#endif /* !CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+
 /* The vectors to use on return from EL0. e.g. to remap the kernel */
 DECLARE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector);
 
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -23,6 +23,7 @@
 #include <asm/cpu.h>
 #include <asm/cputype.h>
 #include <asm/cpufeature.h>
+#include <asm/vectors.h>
 
 static bool __maybe_unused
 is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope)
@@ -67,6 +68,7 @@ cpu_enable_trap_ctr_access(const struct
 #include <asm/mmu_context.h>
 #include <asm/cacheflush.h>
 
+static bool __hardenbp_enab;
 DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
 
 #ifdef CONFIG_KVM
@@ -124,6 +126,7 @@ static void __install_bp_hardening_cb(bp
 	__this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
 	__this_cpu_write(bp_hardening_data.fn, fn);
 	__this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start);
+	__hardenbp_enab = true;
 	spin_unlock(&bp_lock);
 }
 #else
@@ -137,6 +140,7 @@ static void __install_bp_hardening_cb(bp
 				      const char *hyp_vecs_end)
 {
 	__this_cpu_write(bp_hardening_data.fn, fn);
+	__hardenbp_enab = true;
 }
 #endif	/* CONFIG_KVM */
 
@@ -553,9 +557,207 @@ const struct arm64_cpu_capabilities arm6
 	},
 #endif
 	{
+		.desc = "Spectre-BHB",
+		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
+		.capability = ARM64_SPECTRE_BHB,
+		.matches = is_spectre_bhb_affected,
+		.cpu_enable = spectre_bhb_enable_mitigation,
+	},
+	{
 	}
 };
 
+/*
+ * We try to ensure that the mitigation state can never change as the result of
+ * onlining a late CPU.
+ */
+static void update_mitigation_state(enum mitigation_state *oldp,
+				    enum mitigation_state new)
+{
+	enum mitigation_state state;
+
+	do {
+		state = READ_ONCE(*oldp);
+		if (new <= state)
+			break;
+	} while (cmpxchg_relaxed(oldp, state, new) != state);
+}
+
+/*
+ * Spectre BHB.
+ *
+ * A CPU is either:
+ * - Mitigated by a branchy loop a CPU specific number of times, and listed
+ *   in our "loop mitigated list".
+ * - Mitigated in software by the firmware Spectre v2 call.
+ * - Has the 'Exception Clears Branch History Buffer' (ECBHB) feature, so no
+ *   software mitigation in the vectors is needed.
+ * - Has CSV2.3, so is unaffected.
+ */
+static enum mitigation_state spectre_bhb_state;
+
+enum mitigation_state arm64_get_spectre_bhb_state(void)
+{
+	return spectre_bhb_state;
+}
+
+/*
+ * This must be called with SCOPE_LOCAL_CPU for each type of CPU, before any
+ * SCOPE_SYSTEM call will give the right answer.
+ */
+u8 spectre_bhb_loop_affected(int scope)
+{
+	u8 k = 0;
+	static u8 max_bhb_k;
+
+	if (scope == SCOPE_LOCAL_CPU) {
+		static const struct midr_range spectre_bhb_k32_list[] = {
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A78),
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A78C),
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_X1),
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A710),
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_X2),
+			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2),
+			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1),
+			{},
+		};
+		static const struct midr_range spectre_bhb_k24_list[] = {
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A77),
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A76),
+			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1),
+			{},
+		};
+		static const struct midr_range spectre_bhb_k8_list[] = {
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
+			MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
+			{},
+		};
+
+		if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k32_list))
+			k = 32;
+		else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k24_list))
+			k = 24;
+		else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k8_list))
+			k =  8;
+
+		max_bhb_k = max(max_bhb_k, k);
+	} else {
+		k = max_bhb_k;
+	}
+
+	return k;
+}
+
+static enum mitigation_state spectre_bhb_get_cpu_fw_mitigation_state(void)
+{
+	int ret;
+	struct arm_smccc_res res;
+
+	if (psci_ops.smccc_version == SMCCC_VERSION_1_0)
+		return SPECTRE_VULNERABLE;
+
+	switch (psci_ops.conduit) {
+	case PSCI_CONDUIT_HVC:
+		arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
+				  ARM_SMCCC_ARCH_WORKAROUND_3, &res);
+		break;
+
+	case PSCI_CONDUIT_SMC:
+		arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
+				  ARM_SMCCC_ARCH_WORKAROUND_3, &res);
+		break;
+
+	default:
+		return SPECTRE_VULNERABLE;
+	}
+
+	ret = res.a0;
+	switch (ret) {
+	case SMCCC_RET_SUCCESS:
+		return SPECTRE_MITIGATED;
+	case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED:
+		return SPECTRE_UNAFFECTED;
+	default:
+	case SMCCC_RET_NOT_SUPPORTED:
+		return SPECTRE_VULNERABLE;
+	}
+}
+
+static bool is_spectre_bhb_fw_affected(int scope)
+{
+	static bool system_affected;
+	enum mitigation_state fw_state;
+	bool has_smccc = (psci_ops.smccc_version >= SMCCC_VERSION_1_1);
+	static const struct midr_range spectre_bhb_firmware_mitigated_list[] = {
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
+		MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
+		{},
+	};
+	bool cpu_in_list = is_midr_in_range_list(read_cpuid_id(),
+					 spectre_bhb_firmware_mitigated_list);
+
+	if (scope != SCOPE_LOCAL_CPU)
+		return system_affected;
+
+	fw_state = spectre_bhb_get_cpu_fw_mitigation_state();
+	if (cpu_in_list || (has_smccc && fw_state == SPECTRE_MITIGATED)) {
+		system_affected = true;
+		return true;
+	}
+
+	return false;
+}
+
+static bool supports_ecbhb(int scope)
+{
+	u64 mmfr1;
+
+	if (scope == SCOPE_LOCAL_CPU)
+		mmfr1 = read_sysreg_s(SYS_ID_AA64MMFR1_EL1);
+	else
+		mmfr1 = read_system_reg(SYS_ID_AA64MMFR1_EL1);
+
+	return cpuid_feature_extract_unsigned_field(mmfr1,
+						    ID_AA64MMFR1_ECBHB_SHIFT);
+}
+
+bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry,
+			     int scope)
+{
+	WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
+
+	if (supports_csv2p3(scope))
+		return false;
+
+	if (spectre_bhb_loop_affected(scope))
+		return true;
+
+	if (is_spectre_bhb_fw_affected(scope))
+		return true;
+
+	return false;
+}
+
+static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot)
+{
+	const char *v = arm64_get_bp_hardening_vector(slot);
+
+	if (slot < 0)
+		return;
+
+	__this_cpu_write(this_cpu_vector, v);
+
+	/*
+	 * When KPTI is in use, the vectors are switched when exiting to
+	 * user-space.
+	 */
+	if (arm64_kernel_unmapped_at_el0())
+		return;
+
+	write_sysreg(v, vbar_el1);
+	isb();
+}
+
 #ifdef CONFIG_KVM
 static const char *kvm_bhb_get_vecs_end(const char *start)
 {
@@ -571,7 +773,7 @@ static const char *kvm_bhb_get_vecs_end(
 	return NULL;
 }
 
-void kvm_setup_bhb_slot(const char *hyp_vecs_start)
+static void kvm_setup_bhb_slot(const char *hyp_vecs_start)
 {
 	int cpu, slot = -1;
 	const char *hyp_vecs_end;
@@ -609,5 +811,83 @@ void kvm_setup_bhb_slot(const char *hyp_
 #define __spectre_bhb_loop_k24_start NULL
 #define __spectre_bhb_loop_k32_start NULL
 
-void kvm_setup_bhb_slot(const char *hyp_vecs_start) { };
+static void kvm_setup_bhb_slot(const char *hyp_vecs_start) { };
 #endif
+
+static bool is_spectrev2_safe(void)
+{
+	return !is_midr_in_range_list(read_cpuid_id(),
+				      arm64_bp_harden_smccc_cpus);
+}
+
+void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry)
+{
+	enum mitigation_state fw_state, state = SPECTRE_VULNERABLE;
+
+	if (!is_spectre_bhb_affected(entry, SCOPE_LOCAL_CPU))
+		return;
+
+	if (!is_spectrev2_safe() &&  !__hardenbp_enab) {
+		/* No point mitigating Spectre-BHB alone. */
+	} else if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY)) {
+		pr_info_once("spectre-bhb mitigation disabled by compile time option\n");
+	} else if (cpu_mitigations_off()) {
+		pr_info_once("spectre-bhb mitigation disabled by command line option\n");
+	} else if (supports_ecbhb(SCOPE_LOCAL_CPU)) {
+		state = SPECTRE_MITIGATED;
+	} else if (spectre_bhb_loop_affected(SCOPE_LOCAL_CPU)) {
+		switch (spectre_bhb_loop_affected(SCOPE_SYSTEM)) {
+		case 8:
+			kvm_setup_bhb_slot(__spectre_bhb_loop_k8_start);
+			break;
+		case 24:
+			kvm_setup_bhb_slot(__spectre_bhb_loop_k24_start);
+			break;
+		case 32:
+			kvm_setup_bhb_slot(__spectre_bhb_loop_k32_start);
+			break;
+		default:
+			WARN_ON_ONCE(1);
+		}
+		this_cpu_set_vectors(EL1_VECTOR_BHB_LOOP);
+
+		state = SPECTRE_MITIGATED;
+	} else if (is_spectre_bhb_fw_affected(SCOPE_LOCAL_CPU)) {
+		fw_state = spectre_bhb_get_cpu_fw_mitigation_state();
+		if (fw_state == SPECTRE_MITIGATED) {
+			kvm_setup_bhb_slot(__smccc_workaround_3_smc_start);
+			this_cpu_set_vectors(EL1_VECTOR_BHB_FW);
+
+			/*
+			 * With WA3 in the vectors, the WA1 calls can be
+			 * removed.
+			 */
+			__this_cpu_write(bp_hardening_data.fn, NULL);
+
+			state = SPECTRE_MITIGATED;
+		}
+	}
+
+	update_mitigation_state(&spectre_bhb_state, state);
+}
+
+/* Patched to correct the immediate */
+void __init spectre_bhb_patch_loop_iter(struct alt_instr *alt,
+					__le32 *origptr, __le32 *updptr, int nr_inst)
+{
+	u8 rd;
+	u32 insn;
+	u16 loop_count = spectre_bhb_loop_affected(SCOPE_SYSTEM);
+
+	BUG_ON(nr_inst != 1); /* MOV -> MOV */
+
+	if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY))
+		return;
+
+	insn = le32_to_cpu(*origptr);
+	rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, insn);
+	insn = aarch64_insn_gen_movewide(rd, loop_count, 0,
+					 AARCH64_INSN_VARIANT_64BIT,
+					 AARCH64_INSN_MOVEWIDE_ZERO);
+	*updptr++ = cpu_to_le32(insn);
+}
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -136,6 +136,10 @@ el1_hvc_guest:
 	/* ARM_SMCCC_ARCH_WORKAROUND_2 handling */
 	eor	w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_1 ^ \
 			  ARM_SMCCC_ARCH_WORKAROUND_2)
+	cbz	w1, wa_epilogue
+
+	eor	w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_2 ^ \
+			  ARM_SMCCC_ARCH_WORKAROUND_3)
 	cbnz	w1, el1_trap
 
 #ifdef CONFIG_ARM64_SSBD

[PATCH 4.9 41/43] KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit a5905d6af492ee6a4a2205f0d550b3f931b03d03 upstream.

KVM allows the guest to discover whether the ARCH_WORKAROUND SMCCC are
implemented, and to preserve that state during migration through its
firmware register interface.

Add the necessary boiler plate for SMCCC_ARCH_WORKAROUND_3.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ kvm code moved to arch/arm/kvm, removed fw regs ABI. Added 32bit stub ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm/include/asm/kvm_host.h   |    5 +++++
 arch/arm/kvm/psci.c               |    4 ++++
 arch/arm64/include/asm/kvm_host.h |    4 ++++
 3 files changed, 13 insertions(+)

--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -349,4 +349,9 @@ static inline int kvm_arm_have_ssbd(void
 	return KVM_SSBD_UNKNOWN;
 }
 
+static inline bool kvm_arm_spectre_bhb_mitigated(void)
+{
+	/* 32bit guests don't need firmware for this */
+	return false;
+}
 #endif /* __ARM_KVM_HOST_H__ */
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -431,6 +431,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu
 				break;
 			}
 			break;
+		case ARM_SMCCC_ARCH_WORKAROUND_3:
+			if (kvm_arm_spectre_bhb_mitigated())
+				val = SMCCC_RET_SUCCESS;
+			break;
 		}
 		break;
 	default:
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -452,4 +452,8 @@ static inline int kvm_arm_have_ssbd(void
 	}
 }
 
+static inline bool kvm_arm_spectre_bhb_mitigated(void)
+{
+	return arm64_get_spectre_bhb_state() == SPECTRE_MITIGATED;
+}
 #endif /* __ARM64_KVM_HOST_H__ */

[PATCH 4.9 42/43] arm64: add ID_AA64ISAR2_EL1 sys register

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 9e45365f1469ef2b934f9d035975dbc9ad352116 upstream.

This is a new ID register, introduced in 8.7.

Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Reiji Watanabe <reijiw@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211210165432.8106-3-joey.gouly@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/cpu.h    |    1 +
 arch/arm64/include/asm/sysreg.h |    1 +
 arch/arm64/kernel/cpufeature.c  |    9 +++++++++
 arch/arm64/kernel/cpuinfo.c     |    1 +
 4 files changed, 12 insertions(+)

--- a/arch/arm64/include/asm/cpu.h
+++ b/arch/arm64/include/asm/cpu.h
@@ -36,6 +36,7 @@ struct cpuinfo_arm64 {
 	u64		reg_id_aa64dfr1;
 	u64		reg_id_aa64isar0;
 	u64		reg_id_aa64isar1;
+	u64		reg_id_aa64isar2;
 	u64		reg_id_aa64mmfr0;
 	u64		reg_id_aa64mmfr1;
 	u64		reg_id_aa64mmfr2;
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -70,6 +70,7 @@
 
 #define SYS_ID_AA64ISAR0_EL1		sys_reg(3, 0, 0, 6, 0)
 #define SYS_ID_AA64ISAR1_EL1		sys_reg(3, 0, 0, 6, 1)
+#define SYS_ID_AA64ISAR2_EL1		sys_reg(3, 0, 0, 6, 2)
 
 #define SYS_ID_AA64MMFR0_EL1		sys_reg(3, 0, 0, 7, 0)
 #define SYS_ID_AA64MMFR1_EL1		sys_reg(3, 0, 0, 7, 1)
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -98,6 +98,10 @@ static const struct arm64_ftr_bits ftr_i
 	ARM64_FTR_END,
 };
 
+static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
+	ARM64_FTR_END,
+};
+
 static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
@@ -332,6 +336,7 @@ static const struct __ftr_reg_entry {
 	/* Op1 = 0, CRn = 0, CRm = 6 */
 	ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
 	ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_aa64raz),
+	ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
 
 	/* Op1 = 0, CRn = 0, CRm = 7 */
 	ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
@@ -459,6 +464,7 @@ void __init init_cpu_features(struct cpu
 	init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
 	init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
 	init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
+	init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
 	init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
 	init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
 	init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
@@ -570,6 +576,8 @@ void update_cpu_features(int cpu,
 				      info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
 	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
 				      info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
+	taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
+				      info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
 
 	/*
 	 * Differing PARange support is fine as long as all peripherals and
@@ -689,6 +697,7 @@ static u64 __raw_read_system_reg(u32 sys
 	case SYS_ID_AA64MMFR2_EL1:	return read_cpuid(ID_AA64MMFR2_EL1);
 	case SYS_ID_AA64ISAR0_EL1:	return read_cpuid(ID_AA64ISAR0_EL1);
 	case SYS_ID_AA64ISAR1_EL1:	return read_cpuid(ID_AA64ISAR1_EL1);
+	case SYS_ID_AA64ISAR2_EL1:	return read_cpuid(ID_AA64ISAR2_EL1);
 
 	case SYS_CNTFRQ_EL0:		return read_cpuid(CNTFRQ_EL0);
 	case SYS_CTR_EL0:		return read_cpuid(CTR_EL0);
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -335,6 +335,7 @@ static void __cpuinfo_store_cpu(struct c
 	info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1);
 	info->reg_id_aa64isar0 = read_cpuid(ID_AA64ISAR0_EL1);
 	info->reg_id_aa64isar1 = read_cpuid(ID_AA64ISAR1_EL1);
+	info->reg_id_aa64isar2 = read_cpuid(ID_AA64ISAR2_EL1);
 	info->reg_id_aa64mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
 	info->reg_id_aa64mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
 	info->reg_id_aa64mmfr2 = read_cpuid(ID_AA64MMFR2_EL1);

[PATCH 4.9 43/43] arm64: Use the clearbhb instruction in mitigations

[Greg Kroah-Hartman]

From: James Morse <james.morse@arm.com>

commit 228a26b912287934789023b4132ba76065d9491c upstream.

Future CPUs may implement a clearbhb instruction that is sufficient
to mitigate SpectreBHB. CPUs that implement this instruction, but
not CSV2.3 must be affected by Spectre-BHB.

Add support to use this instruction as the BHB mitigation on CPUs
that support it. The instruction is in the hint space, so it will
be treated by a NOP as older CPUs.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ modified for stable: Use a KVM vector template instead of alternatives ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/arm64/include/asm/assembler.h  |    7 +++++++
 arch/arm64/include/asm/cpufeature.h |   13 +++++++++++++
 arch/arm64/include/asm/sysreg.h     |    3 +++
 arch/arm64/include/asm/vectors.h    |    7 +++++++
 arch/arm64/kernel/bpi.S             |    5 +++++
 arch/arm64/kernel/cpu_errata.c      |   14 ++++++++++++++
 arch/arm64/kernel/cpufeature.c      |    1 +
 arch/arm64/kernel/entry.S           |    8 ++++++++
 8 files changed, 58 insertions(+)

--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -95,6 +95,13 @@
 	.endm
 
 /*
+ * Clear Branch History instruction
+ */
+	.macro clearbhb
+	hint	#22
+	.endm
+
+/*
  * Sanitise a 64-bit bounded index wrt speculation, returning zero if out
  * of bounds.
  */
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -387,6 +387,19 @@ static inline bool supports_csv2p3(int s
 	return csv2_val == 3;
 }
 
+static inline bool supports_clearbhb(int scope)
+{
+	u64 isar2;
+
+	if (scope == SCOPE_LOCAL_CPU)
+		isar2 = read_sysreg_s(SYS_ID_AA64ISAR2_EL1);
+	else
+		isar2 = read_system_reg(SYS_ID_AA64ISAR2_EL1);
+
+	return cpuid_feature_extract_unsigned_field(isar2,
+						    ID_AA64ISAR2_CLEARBHB_SHIFT);
+}
+
 static inline bool system_supports_32bit_el0(void)
 {
 	return cpus_have_const_cap(ARM64_HAS_32BIT_EL0);
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -174,6 +174,9 @@
 #define ID_AA64ISAR0_SHA1_SHIFT		8
 #define ID_AA64ISAR0_AES_SHIFT		4
 
+/* id_aa64isar2 */
+#define ID_AA64ISAR2_CLEARBHB_SHIFT	28
+
 /* id_aa64pfr0 */
 #define ID_AA64PFR0_CSV3_SHIFT		60
 #define ID_AA64PFR0_CSV2_SHIFT		56
--- a/arch/arm64/include/asm/vectors.h
+++ b/arch/arm64/include/asm/vectors.h
@@ -33,6 +33,12 @@ enum arm64_bp_harden_el1_vectors {
 	 * canonical vectors.
 	 */
 	EL1_VECTOR_BHB_FW,
+
+	/*
+	 * Use the ClearBHB instruction, before branching to the canonical
+	 * vectors.
+	 */
+	EL1_VECTOR_BHB_CLEAR_INSN,
 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
 
 	/*
@@ -44,6 +50,7 @@ enum arm64_bp_harden_el1_vectors {
 #ifndef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
 #define EL1_VECTOR_BHB_LOOP		-1
 #define EL1_VECTOR_BHB_FW		-1
+#define EL1_VECTOR_BHB_CLEAR_INSN	-1
 #endif /* !CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
 
 /* The vectors to use on return from EL0. e.g. to remap the kernel */
--- a/arch/arm64/kernel/bpi.S
+++ b/arch/arm64/kernel/bpi.S
@@ -123,3 +123,8 @@ ENTRY(__spectre_bhb_loop_k32_start)
 	ldp     x0, x1, [sp, #(8 * 0)]
 	add     sp, sp, #(8 * 2)
 ENTRY(__spectre_bhb_loop_k32_end)
+
+ENTRY(__spectre_bhb_clearbhb_start)
+	hint	#22	/* aka clearbhb */
+	isb
+ENTRY(__spectre_bhb_clearbhb_end)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -84,6 +84,8 @@ extern char __spectre_bhb_loop_k24_start
 extern char __spectre_bhb_loop_k24_end[];
 extern char __spectre_bhb_loop_k32_start[];
 extern char __spectre_bhb_loop_k32_end[];
+extern char __spectre_bhb_clearbhb_start[];
+extern char __spectre_bhb_clearbhb_end[];
 
 static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
 				const char *hyp_vecs_end)
@@ -590,6 +592,7 @@ static void update_mitigation_state(enum
  * - Mitigated by a branchy loop a CPU specific number of times, and listed
  *   in our "loop mitigated list".
  * - Mitigated in software by the firmware Spectre v2 call.
+ * - Has the ClearBHB instruction to perform the mitigation.
  * - Has the 'Exception Clears Branch History Buffer' (ECBHB) feature, so no
  *   software mitigation in the vectors is needed.
  * - Has CSV2.3, so is unaffected.
@@ -729,6 +732,9 @@ bool is_spectre_bhb_affected(const struc
 	if (supports_csv2p3(scope))
 		return false;
 
+	if (supports_clearbhb(scope))
+		return true;
+
 	if (spectre_bhb_loop_affected(scope))
 		return true;
 
@@ -769,6 +775,8 @@ static const char *kvm_bhb_get_vecs_end(
 		return __spectre_bhb_loop_k24_end;
 	else if (start == __spectre_bhb_loop_k32_start)
 		return __spectre_bhb_loop_k32_end;
+	else if (start == __spectre_bhb_clearbhb_start)
+		return __spectre_bhb_clearbhb_end;
 
 	return NULL;
 }
@@ -810,6 +818,7 @@ static void kvm_setup_bhb_slot(const cha
 #define __spectre_bhb_loop_k8_start NULL
 #define __spectre_bhb_loop_k24_start NULL
 #define __spectre_bhb_loop_k32_start NULL
+#define __spectre_bhb_clearbhb_start NULL
 
 static void kvm_setup_bhb_slot(const char *hyp_vecs_start) { };
 #endif
@@ -835,6 +844,11 @@ void spectre_bhb_enable_mitigation(const
 		pr_info_once("spectre-bhb mitigation disabled by command line option\n");
 	} else if (supports_ecbhb(SCOPE_LOCAL_CPU)) {
 		state = SPECTRE_MITIGATED;
+	} else if (supports_clearbhb(SCOPE_LOCAL_CPU)) {
+		kvm_setup_bhb_slot(__spectre_bhb_clearbhb_start);
+		this_cpu_set_vectors(EL1_VECTOR_BHB_CLEAR_INSN);
+
+		state = SPECTRE_MITIGATED;
 	} else if (spectre_bhb_loop_affected(SCOPE_LOCAL_CPU)) {
 		switch (spectre_bhb_loop_affected(SCOPE_SYSTEM)) {
 		case 8:
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -99,6 +99,7 @@ static const struct arm64_ftr_bits ftr_i
 };
 
 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
+	ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
 	ARM64_FTR_END,
 };
 
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -932,6 +932,7 @@ __ni_sys_trace:
 #define BHB_MITIGATION_NONE	0
 #define BHB_MITIGATION_LOOP	1
 #define BHB_MITIGATION_FW	2
+#define BHB_MITIGATION_INSN	3
 
 	.macro tramp_ventry, vector_start, regsize, kpti, bhb
 	.align	7
@@ -948,6 +949,11 @@ __ni_sys_trace:
 	__mitigate_spectre_bhb_loop	x30
 	.endif // \bhb == BHB_MITIGATION_LOOP
 
+	.if	\bhb == BHB_MITIGATION_INSN
+	clearbhb
+	isb
+	.endif // \bhb == BHB_MITIGATION_INSN
+
 	.if	\kpti == 1
 	/*
 	 * Defend against branch aliasing attacks by pushing a dummy
@@ -1023,6 +1029,7 @@ ENTRY(tramp_vectors)
 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
 	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_LOOP
 	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_FW
+	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_INSN
 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
 	generate_tramp_vector	kpti=1, bhb=BHB_MITIGATION_NONE
 END(tramp_vectors)
@@ -1085,6 +1092,7 @@ ENTRY(__bp_harden_el1_vectors)
 #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
 	generate_el1_vector	bhb=BHB_MITIGATION_LOOP
 	generate_el1_vector	bhb=BHB_MITIGATION_FW
+	generate_el1_vector	bhb=BHB_MITIGATION_INSN
 #endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
 END(__bp_harden_el1_vectors)
 	.popsection

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Florian Fainelli]

On 4/6/22 11:26, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 4.9.310 release.
> There are 43 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
> 
> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> Anything received after that time might be too late.
> 
> The whole patch series can be found in one patch at:
> 	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.310-rc1.gz
> or in the git tree and branch at:
> 	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
> 
> thanks,
> 
> greg k-h

On ARCH_BRCMSTB using 32-bit and 64-bit ARM kernels:

Tested-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 659 bytes --]

Hi!

> This is the start of the stable review cycle for the 4.9.310 release.
> There are 43 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.

CIP testing did not find any problems here:

https://gitlab.com/cip-project/cip-testing/linux-stable-rc-ci/-/tree/linux-4.9.y

Tested-by: Pavel Machek (CIP) <pavel@denx.de>

Best regards,
                                                                Pavel
-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 195 bytes --]

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Shuah Khan]

On 4/6/22 12:26 PM, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 4.9.310 release.
> There are 43 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
> 
> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> Anything received after that time might be too late.
> 
> The whole patch series can be found in one patch at:
> 	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.310-rc1.gz
> or in the git tree and branch at:
> 	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
> 
> thanks,
> 
> greg k-h
> 

Compiled and booted on my test system. No dmesg regressions.

Tested-by: Shuah Khan <skhan@linuxfoundation.org>

thanks,
-- Shuah

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Guenter Roeck]

On Wed, Apr 06, 2022 at 08:26:09PM +0200, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 4.9.310 release.
> There are 43 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
> 
> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> Anything received after that time might be too late.
> 

Build results:
	total: 163 pass: 161 fail: 2
Failed builds:
	arm64:allnoconfig
	arm64:tinyconfig
Qemu test results:
	total: 397 pass: 397 fail: 0

arch/arm64/kernel/cpu_errata.c: In function 'is_spectrev2_safe':
arch/arm64/kernel/cpu_errata.c:829:39: error: 'arm64_bp_harden_smccc_cpus' undeclared 

arch/arm64/kernel/cpu_errata.c: In function 'spectre_bhb_enable_mitigation':
arch/arm64/kernel/cpu_errata.c:839:39: error: '__hardenbp_enab' undeclared

arch/arm64/kernel/cpu_errata.c:879:42: error: 'bp_hardening_data' undeclared

Guenter

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Greg Kroah-Hartman]

On Thu, Apr 07, 2022 at 02:32:38AM -0700, Guenter Roeck wrote:
> On Wed, Apr 06, 2022 at 08:26:09PM +0200, Greg Kroah-Hartman wrote:
> > This is the start of the stable review cycle for the 4.9.310 release.
> > There are 43 patches in this series, all will be posted as a response
> > to this one.  If anyone has any issues with these being applied, please
> > let me know.
> > 
> > Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> > Anything received after that time might be too late.
> > 
> 
> Build results:
> 	total: 163 pass: 161 fail: 2
> Failed builds:
> 	arm64:allnoconfig
> 	arm64:tinyconfig
> Qemu test results:
> 	total: 397 pass: 397 fail: 0
> 
> arch/arm64/kernel/cpu_errata.c: In function 'is_spectrev2_safe':
> arch/arm64/kernel/cpu_errata.c:829:39: error: 'arm64_bp_harden_smccc_cpus' undeclared 
> 
> arch/arm64/kernel/cpu_errata.c: In function 'spectre_bhb_enable_mitigation':
> arch/arm64/kernel/cpu_errata.c:839:39: error: '__hardenbp_enab' undeclared
> 
> arch/arm64/kernel/cpu_errata.c:879:42: error: 'bp_hardening_data' undeclared

Ick, odds are James did not build with those two configs :(

James, any chance you can look into this and see what needs to be added
or changed with your patch series?

thanks,

greg k-h

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Naresh Kamboju]

On Wed, 6 Apr 2022 at 23:57, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> This is the start of the stable review cycle for the 4.9.310 release.
> There are 43 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> Anything received after that time might be too late.
>
> The whole patch series can be found in one patch at:
>         https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.310-rc1.gz
> or in the git tree and branch at:
>         git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
>
> thanks,
>
> greg k-h

Results from Linaro’s test farm.

As Guenter reported,
On stable rc 4.9 arm64 build configs allnoconfig and tinyconfig failed.

## Build
* kernel: 4.9.310-rc1
* git: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
* git branch: linux-4.9.y
* git commit: b5f0e9d665c30ceb3bee566518a1020e54d7bc1f
* git describe: v4.9.309-44-gb5f0e9d665c3
* test details:
https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-4.9.y-sanity/build/v4.9.309-44-gb5f0e9d665c3

## Test Regressions (compared to v4.9.309-163-geeae539a0d5c)
* arm64, build
  - arm64-clang-11-allnoconfig
  - arm64-clang-11-tinyconfig
  - arm64-clang-12-allnoconfig
  - arm64-clang-12-tinyconfig
  - arm64-clang-13-allnoconfig
  - arm64-clang-13-tinyconfig
  - arm64-clang-nightly-allnoconfig
  - arm64-clang-nightly-tinyconfig
  - arm64-gcc-10-allnoconfig
  - arm64-gcc-10-tinyconfig
  - arm64-gcc-11-allnoconfig
  - arm64-gcc-11-tinyconfig
  - arm64-gcc-8-allnoconfig
  - arm64-gcc-8-tinyconfig
  - arm64-gcc-9-allnoconfig
  - arm64-gcc-9-tinyconfig


Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>

--
Linaro LKFT
https://lkft.linaro.org

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Naresh Kamboju]

On Wed, 6 Apr 2022 at 23:57, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> This is the start of the stable review cycle for the 4.9.310 release.
> There are 43 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> Anything received after that time might be too late.
>
> The whole patch series can be found in one patch at:
>         https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.310-rc1.gz
> or in the git tree and branch at:
>         git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
>
> thanks,
>
> greg k-h

Results from Linaro’s test farm.

As Guenter reported,
On stable-rc 4.9 arm64 build configs allnoconfig and tinyconfig failed [1].

## Build
* kernel: 4.9.310-rc1
* git: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
* git branch: linux-4.9.y
* git commit: b5f0e9d665c30ceb3bee566518a1020e54d7bc1f
* git describe: v4.9.309-44-gb5f0e9d665c3
* test details:
https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-4.9.y-sanity/build/v4.9.309-44-gb5f0e9d665c3

## Test Regressions (compared to v4.9.309-163-geeae539a0d5c)
* arm64, build
  - arm64-clang-11-allnoconfig
  - arm64-clang-11-tinyconfig
  - arm64-clang-12-allnoconfig
  - arm64-clang-12-tinyconfig
  - arm64-clang-13-allnoconfig
  - arm64-clang-13-tinyconfig
  - arm64-clang-nightly-allnoconfig
  - arm64-clang-nightly-tinyconfig
  - arm64-gcc-10-allnoconfig
  - arm64-gcc-10-tinyconfig
  - arm64-gcc-11-allnoconfig
  - arm64-gcc-11-tinyconfig
  - arm64-gcc-8-allnoconfig
  - arm64-gcc-8-tinyconfig
  - arm64-gcc-9-allnoconfig
  - arm64-gcc-9-tinyconfig


Build error:
------------

arch/arm64/kernel/cpu_errata.c: In function 'is_spectrev2_safe':
arch/arm64/kernel/cpu_errata.c:829:39: error:
'arm64_bp_harden_smccc_cpus' undeclared (first use in this function);
did you mean 'arm64_bp_harden_el1_vectors'?
  829 |                                       arm64_bp_harden_smccc_cpus);
      |                                       ^~~~~~~~~~~~~~~~~~~~~~~~~~
      |                                       arm64_bp_harden_el1_vectors
arch/arm64/kernel/cpu_errata.c:829:39: note: each undeclared
identifier is reported only once for each function it appears in
arch/arm64/kernel/cpu_errata.c: In function 'spectre_bhb_enable_mitigation':
arch/arm64/kernel/cpu_errata.c:839:39: error: '__hardenbp_enab'
undeclared (first use in this function)
  839 |         if (!is_spectrev2_safe() &&  !__hardenbp_enab) {
      |                                       ^~~~~~~~~~~~~~~
In file included from include/asm-generic/percpu.h:6,
                 from arch/arm64/include/asm/percpu.h:279,
                 from include/linux/percpu.h:12,
                 from arch/arm64/include/asm/mmu.h:23,
                 from include/linux/mm_types.h:17,
                 from include/linux/sched.h:27,
                 from include/linux/ratelimit.h:5,
                 from include/linux/device.h:27,
                 from include/linux/node.h:17,
                 from include/linux/cpu.h:16,
                 from arch/arm64/include/asm/cpu.h:19,
                 from arch/arm64/kernel/cpu_errata.c:23:
arch/arm64/kernel/cpu_errata.c:879:42: error: 'bp_hardening_data'
undeclared (first use in this function)
  879 |                         __this_cpu_write(bp_hardening_data.fn, NULL);
      |                                          ^~~~~~~~~~~~~~~~~
include/linux/percpu-defs.h:236:54: note: in definition of macro
'__verify_pcpu_ptr'
  236 |         const void __percpu *__vpp_verify = (typeof((ptr) +
0))NULL;    \
      |                                                      ^~~
include/linux/percpu-defs.h:438:41: note: in expansion of macro
'__pcpu_size_call'
  438 | #define raw_cpu_write(pcp, val)
__pcpu_size_call(raw_cpu_write_, pcp, val)
      |                                         ^~~~~~~~~~~~~~~~
include/linux/percpu-defs.h:469:9: note: in expansion of macro 'raw_cpu_write'
  469 |         raw_cpu_write(pcp, val);
         \
      |         ^~~~~~~~~~~~~
arch/arm64/kernel/cpu_errata.c:879:25: note: in expansion of macro
'__this_cpu_write'
  879 |                         __this_cpu_write(bp_hardening_data.fn, NULL);
      |                         ^~~~~~~~~~~~~~~~
make[2]: *** [scripts/Makefile.build:307:
arch/arm64/kernel/cpu_errata.o] Error 1


Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>

steps to reproduce:

# To install tuxmake on your system globally:
# sudo pip3 install -U tuxmake

 tuxmake --runtime podman --target-arch arm64 --toolchain gcc-11
--kconfig tinyconfig


--
Linaro LKFT
https://lkft.linaro.org

[1] https://builds.tuxbuild.com/27R7yjNqw1ahQiOJ16BgcTn7BcZ/

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[James Morse]

Hi Greg,

On 07/04/2022 11:23, Greg Kroah-Hartman wrote:
> On Thu, Apr 07, 2022 at 02:32:38AM -0700, Guenter Roeck wrote:
>> On Wed, Apr 06, 2022 at 08:26:09PM +0200, Greg Kroah-Hartman wrote:
>>> This is the start of the stable review cycle for the 4.9.310 release.
>>> There are 43 patches in this series, all will be posted as a response
>>> to this one.  If anyone has any issues with these being applied, please
>>> let me know.
>>>
>>> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
>>> Anything received after that time might be too late.
>>>
>>
>> Build results:
>> 	total: 163 pass: 161 fail: 2
>> Failed builds:
>> 	arm64:allnoconfig
>> 	arm64:tinyconfig
>> Qemu test results:
>> 	total: 397 pass: 397 fail: 0
>>
>> arch/arm64/kernel/cpu_errata.c: In function 'is_spectrev2_safe':
>> arch/arm64/kernel/cpu_errata.c:829:39: error: 'arm64_bp_harden_smccc_cpus' undeclared 
>>
>> arch/arm64/kernel/cpu_errata.c: In function 'spectre_bhb_enable_mitigation':
>> arch/arm64/kernel/cpu_errata.c:839:39: error: '__hardenbp_enab' undeclared
>>
>> arch/arm64/kernel/cpu_errata.c:879:42: error: 'bp_hardening_data' undeclared
> 
> Ick, odds are James did not build with those two configs :(

I'm sure I tried allnoconfig - but evidently messed something up.


> James, any chance you can look into this and see what needs to be added
> or changed with your patch series?

Will do,...


Thanks,

James

Re: [PATCH 4.9 00/43] 4.9.310-rc1 review

[Greg Kroah-Hartman]

On Thu, Apr 07, 2022 at 06:20:28PM +0100, James Morse wrote:
> Hi Greg,
> 
> On 07/04/2022 11:23, Greg Kroah-Hartman wrote:
> > On Thu, Apr 07, 2022 at 02:32:38AM -0700, Guenter Roeck wrote:
> >> On Wed, Apr 06, 2022 at 08:26:09PM +0200, Greg Kroah-Hartman wrote:
> >>> This is the start of the stable review cycle for the 4.9.310 release.
> >>> There are 43 patches in this series, all will be posted as a response
> >>> to this one.  If anyone has any issues with these being applied, please
> >>> let me know.
> >>>
> >>> Responses should be made by Fri, 08 Apr 2022 18:24:27 +0000.
> >>> Anything received after that time might be too late.
> >>>
> >>
> >> Build results:
> >> 	total: 163 pass: 161 fail: 2
> >> Failed builds:
> >> 	arm64:allnoconfig
> >> 	arm64:tinyconfig
> >> Qemu test results:
> >> 	total: 397 pass: 397 fail: 0
> >>
> >> arch/arm64/kernel/cpu_errata.c: In function 'is_spectrev2_safe':
> >> arch/arm64/kernel/cpu_errata.c:829:39: error: 'arm64_bp_harden_smccc_cpus' undeclared 
> >>
> >> arch/arm64/kernel/cpu_errata.c: In function 'spectre_bhb_enable_mitigation':
> >> arch/arm64/kernel/cpu_errata.c:839:39: error: '__hardenbp_enab' undeclared
> >>
> >> arch/arm64/kernel/cpu_errata.c:879:42: error: 'bp_hardening_data' undeclared
> > 
> > Ick, odds are James did not build with those two configs :(
> 
> I'm sure I tried allnoconfig - but evidently messed something up.
> 
> 
> > James, any chance you can look into this and see what needs to be added
> > or changed with your patch series?
> 
> Will do,...

Thanks for the fixup patch, this passes my local build tests so I think
I'll push out the release now.

greg k-h