On 2020-08-24 19:27, Catalin Marinas wrote:
From: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Add the cpufeature and hwcap entries to detect the presence of MTE. Any
secondary CPU not supporting the feature, if detected on the boot CPU,
will be parked.
Add the minimum SCTLR_EL1 and HCR_EL2 bits for enabling MTE. The Normal
Tagged memory type is configured in MAIR_EL1 before the MMU is enabled
in order to avoid disrupting other CPUs in the CnP domain.
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Co-developed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx>
---
Notes:
v8:
- Move the SCTLR_EL1, MAIR_EL1, GCR_EL1 and TFSR*_EL1
initialisation to
__cpu_setup before the MMU is enabled. While early MAIR_EL1 is
desirable to avoid conflicting with other CPUs in a CnP domain
the
TFSR_EL1 and GCR_EL1 will only come in handy later when support
for
in-kernel MTE is added.
v7:
- Hide the MTE ID register field for guests until MTE gains support
for KVM.
arch/arm64/include/asm/cpucaps.h | 3 ++-
arch/arm64/include/asm/cpufeature.h | 6 ++++++
arch/arm64/include/asm/hwcap.h | 2 +-
arch/arm64/include/asm/kvm_arm.h | 2 +-
arch/arm64/include/asm/sysreg.h | 1 +
arch/arm64/include/uapi/asm/hwcap.h | 2 +-
arch/arm64/kernel/cpufeature.c | 17 +++++++++++++++++
arch/arm64/kernel/cpuinfo.c | 2 +-
arch/arm64/kvm/sys_regs.c | 2 ++
arch/arm64/mm/proc.S | 24 ++++++++++++++++++++++++
10 files changed, 56 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/include/asm/cpucaps.h
b/arch/arm64/include/asm/cpucaps.h
index 07b643a70710..1937653b05a3 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -64,7 +64,8 @@
#define ARM64_BTI 54
#define ARM64_HAS_ARMv8_4_TTL 55
#define ARM64_HAS_TLB_RANGE 56
+#define ARM64_MTE 57
-#define ARM64_NCAPS 57
+#define ARM64_NCAPS 58
#endif /* __ASM_CPUCAPS_H */
diff --git a/arch/arm64/include/asm/cpufeature.h
b/arch/arm64/include/asm/cpufeature.h
index 89b4f0142c28..680b5b36ddd5 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -681,6 +681,12 @@ static __always_inline bool
system_uses_irq_prio_masking(void)
cpus_have_const_cap(ARM64_HAS_IRQ_PRIO_MASKING);
}
+static inline bool system_supports_mte(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_MTE) &&
+ cpus_have_const_cap(ARM64_MTE);
+}
+
static inline bool system_has_prio_mask_debugging(void)
{
return IS_ENABLED(CONFIG_ARM64_DEBUG_PRIORITY_MASKING) &&
diff --git a/arch/arm64/include/asm/hwcap.h
b/arch/arm64/include/asm/hwcap.h
index 22f73fe09030..0d4a6741b6a5 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -95,7 +95,7 @@
#define KERNEL_HWCAP_DGH __khwcap2_feature(DGH)
#define KERNEL_HWCAP_RNG __khwcap2_feature(RNG)
#define KERNEL_HWCAP_BTI __khwcap2_feature(BTI)
-/* reserved for KERNEL_HWCAP_MTE __khwcap2_feature(MTE) */
+#define KERNEL_HWCAP_MTE __khwcap2_feature(MTE)
/*
* This yields a mask that user programs can use to figure out what
diff --git a/arch/arm64/include/asm/kvm_arm.h
b/arch/arm64/include/asm/kvm_arm.h
index 8a1cbfd544d6..6c3b2fc922bb 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -78,7 +78,7 @@
HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW | HCR_TLOR | \
HCR_FMO | HCR_IMO)
#define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF)
-#define HCR_HOST_NVHE_FLAGS (HCR_RW | HCR_API | HCR_APK)
+#define HCR_HOST_NVHE_FLAGS (HCR_RW | HCR_API | HCR_APK | HCR_ATA)
#define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H)
Why is HCR_ATA only set for nVHE? HCR_EL2.ATA seems to apply to both,
doesn't it?
/* TCR_EL2 Registers bits */
[...]
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 077293b5115f..59b91f58efec 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1131,6 +1131,8 @@ static u64 read_id_reg(const struct kvm_vcpu
*vcpu,
if (!vcpu_has_sve(vcpu))
val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT);
val &= ~(0xfUL << ID_AA64PFR0_AMU_SHIFT);
+ } else if (id == SYS_ID_AA64PFR1_EL1) {
+ val &= ~(0xfUL << ID_AA64PFR1_MTE_SHIFT);
Hiding the capability is fine, but where is the handling of trapping
instructions done? They should result in an UNDEF being injected.
Thanks,
M.
--
Jazz is not dead. It just smells funny...
