Errata 1165522, 1319367 and 1530923 each allow TLB entries to be
allocated as a result of a speculative AT instruction. In order to
avoid mandating VHE on certain affected CPUs, apply the workaround to
both the nVHE and the VHE case for all affected CPUs.
Signed-off-by: Andrew Scull <asc...@google.com>
CC: Marc Zyngier <m...@kernel.org>
CC: James Morse <james.mo...@arm.com>
CC: Suzuki K Poulose <suzuki.poul...@arm.com>
CC: Will Deacon <w...@kernel.org>
CC: Steven Price <steven.pr...@arm.com>
---
* From v1 <20200327143941.195626-1-asc...@google.com>:
- Restored registers in VHE path
- RFC: Remove trust in host
---
arch/arm64/Kconfig | 39 ++++++++++++++-----------------
arch/arm64/include/asm/cpucaps.h | 15 ++++++------
arch/arm64/include/asm/kvm_host.h | 4 ----
arch/arm64/include/asm/kvm_hyp.h | 2 +-
arch/arm64/kernel/cpu_errata.c | 25 +++++++++-----------
arch/arm64/kvm/hyp/switch.c | 6 ++---
arch/arm64/kvm/hyp/sysreg-sr.c | 6 +++--
arch/arm64/kvm/hyp/tlb.c | 11 +++++----
8 files changed, 50 insertions(+), 58 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 40fb05d96c60..c0298e8f1a2d 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -524,13 +524,13 @@ config ARM64_ERRATUM_1418040
If unsure, say Y.
-config ARM64_WORKAROUND_SPECULATIVE_AT_VHE
+config ARM64_WORKAROUND_SPECULATIVE_AT
bool
config ARM64_ERRATUM_1165522
- bool "Cortex-A76: Speculative AT instruction using out-of-context
translation regime could cause subsequent request to generate an incorrect
translation"
+ bool "Cortex-A76: 1165522: Speculative AT instruction using
out-of-context translation regime could cause subsequent request to generate an
incorrect translation"
default y
- select ARM64_WORKAROUND_SPECULATIVE_AT_VHE
+ select ARM64_WORKAROUND_SPECULATIVE_AT
help
This option adds a workaround for ARM Cortex-A76 erratum 1165522.
@@ -540,10 +540,23 @@ config ARM64_ERRATUM_1165522
If unsure, say Y.
+config ARM64_ERRATUM_1319367
+ bool "Cortex-A57/A72: 1319537: Speculative AT instruction using
out-of-context translation regime could cause subsequent request to generate an
incorrect translation"
+ default y
+ select ARM64_WORKAROUND_SPECULATIVE_AT
+ help
+ This option adds work arounds for ARM Cortex-A57 erratum 1319537
+ and A72 erratum 1319367
+
+ Cortex-A57 and A72 cores could end-up with corrupted TLBs by
+ speculating an AT instruction during a guest context switch.
+
+ If unsure, say Y.
+
config ARM64_ERRATUM_1530923
- bool "Cortex-A55: Speculative AT instruction using out-of-context
translation regime could cause subsequent request to generate an incorrect
translation"
+ bool "Cortex-A55: 1530923: Speculative AT instruction using
out-of-context translation regime could cause subsequent request to generate an
incorrect translation"
default y
- select ARM64_WORKAROUND_SPECULATIVE_AT_VHE
+ select ARM64_WORKAROUND_SPECULATIVE_AT
help
This option adds a workaround for ARM Cortex-A55 erratum 1530923.
@@ -569,22 +582,6 @@ config ARM64_ERRATUM_1286807
invalidated has been observed by other observers. The
workaround repeats the TLBI+DSB operation.
-config ARM64_WORKAROUND_SPECULATIVE_AT_NVHE
- bool
-
-config ARM64_ERRATUM_1319367
- bool "Cortex-A57/A72: Speculative AT instruction using out-of-context
translation regime could cause subsequent request to generate an incorrect
translation"
- default y
- select ARM64_WORKAROUND_SPECULATIVE_AT_NVHE
- help
- This option adds work arounds for ARM Cortex-A57 erratum 1319537
- and A72 erratum 1319367
-
- Cortex-A57 and A72 cores could end-up with corrupted TLBs by
- speculating an AT instruction during a guest context switch.
-
- If unsure, say Y.
-
config ARM64_ERRATUM_1463225
bool "Cortex-A76: Software Step might prevent interrupt recognition"
default y
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index 8eb5a088ae65..dc70883062ba 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -44,7 +44,7 @@
#define ARM64_SSBS 34
#define ARM64_WORKAROUND_1418040 35
#define ARM64_HAS_SB 36
-#define ARM64_WORKAROUND_SPECULATIVE_AT_VHE 37
+#define ARM64_WORKAROUND_SPECULATIVE_AT 37
#define ARM64_HAS_ADDRESS_AUTH_ARCH 38
#define ARM64_HAS_ADDRESS_AUTH_IMP_DEF 39
#define ARM64_HAS_GENERIC_AUTH_ARCH 40
@@ -55,13 +55,12 @@
#define ARM64_WORKAROUND_CAVIUM_TX2_219_TVM 45
#define ARM64_WORKAROUND_CAVIUM_TX2_219_PRFM 46
#define ARM64_WORKAROUND_1542419 47
-#define ARM64_WORKAROUND_SPECULATIVE_AT_NVHE 48
-#define ARM64_HAS_E0PD 49
-#define ARM64_HAS_RNG 50
-#define ARM64_HAS_AMU_EXTN 51
-#define ARM64_HAS_ADDRESS_AUTH 52
-#define ARM64_HAS_GENERIC_AUTH 53
+#define ARM64_HAS_E0PD 48
+#define ARM64_HAS_RNG 49
+#define ARM64_HAS_AMU_EXTN 50
+#define ARM64_HAS_ADDRESS_AUTH 51
+#define ARM64_HAS_GENERIC_AUTH 52
-#define ARM64_NCAPS 54
+#define ARM64_NCAPS 53
#endif /* __ASM_CPUCAPS_H */
diff --git a/arch/arm64/include/asm/kvm_host.h
b/arch/arm64/include/asm/kvm_host.h
index 32c8a675e5a4..d0e7d7934a1f 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -573,10 +573,6 @@ static inline bool kvm_arch_requires_vhe(void)
if (system_supports_sve())
return true;
- /* Some implementations have defects that confine them to VHE */
- if (cpus_have_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE))
- return true;
-
return false;
}
diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index fe57f60f06a8..238d2e049694 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -102,7 +102,7 @@ static __always_inline void __hyp_text
__load_guest_stage2(struct kvm *kvm)
* above before we can switch to the EL1/EL0 translation regime used by
* the guest.
*/
- asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT_VHE));
+ asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
}
#endif /* __ARM64_KVM_HYP_H__ */
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index df56d2295d16..95006a791026 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -635,7 +635,7 @@ has_neoverse_n1_erratum_1542419(const struct
arm64_cpu_capabilities *entry,
return is_midr_in_range(midr, &range) && has_dic;
}
-#if defined(CONFIG_HARDEN_EL2_VECTORS) || defined(CONFIG_ARM64_ERRATUM_1319367)
+#if defined(CONFIG_HARDEN_EL2_VECTORS)
static const struct midr_range ca57_a72[] = {
MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
@@ -757,12 +757,16 @@ static const struct arm64_cpu_capabilities
erratum_843419_list[] = {
};
#endif
-#ifdef CONFIG_ARM64_WORKAROUND_SPECULATIVE_AT_VHE
-static const struct midr_range erratum_speculative_at_vhe_list[] = {
+#ifdef CONFIG_ARM64_WORKAROUND_SPECULATIVE_AT
+static const struct midr_range erratum_speculative_at_list[] = {
#ifdef CONFIG_ARM64_ERRATUM_1165522
/* Cortex A76 r0p0 to r2p0 */
MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0),
#endif
+#ifdef CONFIG_ARM64_ERRATUM_1319367
+ MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
+ MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
+#endif
#ifdef CONFIG_ARM64_ERRATUM_1530923
/* Cortex A55 r0p0 to r2p0 */
MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 2, 0),
@@ -897,11 +901,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
ERRATA_MIDR_RANGE_LIST(erratum_1418040_list),
},
#endif
-#ifdef CONFIG_ARM64_WORKAROUND_SPECULATIVE_AT_VHE
+#ifdef CONFIG_ARM64_WORKAROUND_SPECULATIVE_AT
{
- .desc = "ARM errata 1165522, 1530923",
- .capability = ARM64_WORKAROUND_SPECULATIVE_AT_VHE,
- ERRATA_MIDR_RANGE_LIST(erratum_speculative_at_vhe_list),
+ .desc = "ARM errata 1165522, 1319367, 1530923",
+ .capability = ARM64_WORKAROUND_SPECULATIVE_AT,
+ ERRATA_MIDR_RANGE_LIST(erratum_speculative_at_list),
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_1463225
@@ -934,13 +938,6 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
.matches = has_neoverse_n1_erratum_1542419,
.cpu_enable = cpu_enable_trap_ctr_access,
},
-#endif
-#ifdef CONFIG_ARM64_ERRATUM_1319367
- {
- .desc = "ARM erratum 1319367",
- .capability = ARM64_WORKAROUND_SPECULATIVE_AT_NVHE,
- ERRATA_MIDR_RANGE_LIST(ca57_a72),
- },
#endif
{
}
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 8a1e81a400e0..651820f537fb 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -138,7 +138,7 @@ static void __hyp_text __activate_traps_nvhe(struct
kvm_vcpu *vcpu)
write_sysreg(val, cptr_el2);
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt;
isb();
@@ -181,7 +181,7 @@ static void deactivate_traps_vhe(void)
* above before we can switch to the EL2/EL0 translation regime used by
* the host.
*/
- asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT_VHE));
+ asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1);
write_sysreg(vectors, vbar_el1);
@@ -192,7 +192,7 @@ static void __hyp_text __deactivate_traps_nvhe(void)
{
u64 mdcr_el2 = read_sysreg(mdcr_el2);
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
u64 val;
/*
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 75b1925763f1..8f56f30d0833 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -118,7 +118,8 @@ static void __hyp_text __sysreg_restore_el1_state(struct
kvm_cpu_context *ctxt)
write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2);
write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1);
- if (!cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (has_vhe() ||
+ !cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR);
write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR);
} else if (!ctxt->__hyp_running_vcpu) {
@@ -149,7 +150,8 @@ static void __hyp_text __sysreg_restore_el1_state(struct
kvm_cpu_context *ctxt)
write_sysreg(ctxt->sys_regs[PAR_EL1], par_el1);
write_sysreg(ctxt->sys_regs[TPIDR_EL1], tpidr_el1);
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE) &&
+ if (!has_vhe() &&
+ cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT) &&
ctxt->__hyp_running_vcpu) {
/*
* Must only be done for host registers, hence the context
diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c
index ceaddbe4279f..59d127204345 100644
--- a/arch/arm64/kvm/hyp/tlb.c
+++ b/arch/arm64/kvm/hyp/tlb.c
@@ -23,7 +23,7 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm
*kvm,
local_irq_save(cxt->flags);
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE)) {
+ if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
/*
* For CPUs that are affected by ARM errata 1165522 or 1530923,
* we cannot trust stage-1 to be in a correct state at that
@@ -63,7 +63,7 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm
*kvm,
static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm *kvm,
struct tlb_inv_context *cxt)
{
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
u64 val;
/*
@@ -79,8 +79,9 @@ static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm
*kvm,
isb();
}
+ /* __load_guest_stage2() includes an ISB for the workaround. */
__load_guest_stage2(kvm);
- isb();
+ asm(ALTERNATIVE("isb", "nop", ARM64_WORKAROUND_SPECULATIVE_AT));
}
static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm,
@@ -103,7 +104,7 @@ static void __hyp_text __tlb_switch_to_host_vhe(struct kvm
*kvm,
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
isb();
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_VHE)) {
+ if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
/* Restore the registers to what they were */
write_sysreg_el1(cxt->tcr, SYS_TCR);
write_sysreg_el1(cxt->sctlr, SYS_SCTLR);
@@ -117,7 +118,7 @@ static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm
*kvm,
{
write_sysreg(0, vttbr_el2);
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ if (cpus_have_const_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {
/* Ensure write of the host VMID */
isb();
/* Restore the host's TCR_EL1 */
--
2.26.1.301.g55bc3eb7cb9-goog
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