Creates far too many conflicts with arm64/for-next/core, to be
resent post -rc1.
This reverts commit f9f5dc19509bbef6f5e675346f1a7d7b846bdb12.
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
arch/arm64/include/asm/cpucaps.h | 2 +-
arch/arm64/include/asm/kvm_asm.h | 2 ++
arch/arm64/kernel/bpi.S | 8 ++++++
arch/arm64/kernel/cpu_errata.c | 55 ++++++++++++++++++++++++++--------------
arch/arm64/kvm/hyp/entry.S | 12 +++++++++
arch/arm64/kvm/hyp/switch.c | 10 ++++++++
6 files changed, 69 insertions(+), 20 deletions(-)
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index c7dfe68fbcc7..d4cc54ed0656 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -43,7 +43,7 @@
#define ARM64_SVE 22
#define ARM64_UNMAP_KERNEL_AT_EL0 23
#define ARM64_HARDEN_BRANCH_PREDICTOR 24
-/* #define ARM64_UNUSED_CAP_TO_BE_REMOVED 25 */
+#define ARM64_HARDEN_BP_POST_GUEST_EXIT 25
#define ARM64_HAS_RAS_EXTN 26
#define ARM64_NCAPS 27
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index f6648a3e4152..d53d40704416 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -71,6 +71,8 @@ extern u32 __kvm_get_mdcr_el2(void);
extern u32 __init_stage2_translation(void);
+extern void __qcom_hyp_sanitize_btac_predictors(void);
+
#else /* __ASSEMBLY__ */
.macro get_host_ctxt reg, tmp
diff --git a/arch/arm64/kernel/bpi.S b/arch/arm64/kernel/bpi.S
index 9404f6aecda7..bb0b67722e86 100644
--- a/arch/arm64/kernel/bpi.S
+++ b/arch/arm64/kernel/bpi.S
@@ -74,6 +74,14 @@ ENTRY(__bp_harden_hyp_vecs_end)
.popsection
+ENTRY(__qcom_hyp_sanitize_link_stack_start)
+ stp x29, x30, [sp, #-16]!
+ .rept 16
+ bl . + 4
+ .endr
+ ldp x29, x30, [sp], #16
+ENTRY(__qcom_hyp_sanitize_link_stack_end)
+
.macro smccc_workaround_1 inst
sub sp, sp, #(8 * 4)
stp x2, x3, [sp, #(8 * 0)]
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index caa73af7d26e..aacdc118c4c9 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -69,6 +69,8 @@ atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1);
DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
#ifdef CONFIG_KVM
+extern char __qcom_hyp_sanitize_link_stack_start[];
+extern char __qcom_hyp_sanitize_link_stack_end[];
extern char __smccc_workaround_1_smc_start[];
extern char __smccc_workaround_1_smc_end[];
extern char __smccc_workaround_1_hvc_start[];
@@ -112,6 +114,8 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
spin_unlock(&bp_lock);
}
#else
+#define __qcom_hyp_sanitize_link_stack_start NULL
+#define __qcom_hyp_sanitize_link_stack_end NULL
#define __smccc_workaround_1_smc_start NULL
#define __smccc_workaround_1_smc_end NULL
#define __smccc_workaround_1_hvc_start NULL
@@ -156,25 +160,12 @@ static void call_hvc_arch_workaround_1(void)
arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
}
-static void qcom_link_stack_sanitization(void)
-{
- u64 tmp;
-
- asm volatile("mov %0, x30 \n"
- ".rept 16 \n"
- "bl . + 4 \n"
- ".endr \n"
- "mov x30, %0 \n"
- : "=&r" (tmp));
-}
-
static int enable_smccc_arch_workaround_1(void *data)
{
const struct arm64_cpu_capabilities *entry = data;
bp_hardening_cb_t cb;
void *smccc_start, *smccc_end;
struct arm_smccc_res res;
- u32 midr = read_cpuid_id();
if (!entry->matches(entry, SCOPE_LOCAL_CPU))
return 0;
@@ -207,15 +198,33 @@ static int enable_smccc_arch_workaround_1(void *data)
return 0;
}
- if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) ||
- ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1))
- cb = qcom_link_stack_sanitization;
-
install_bp_hardening_cb(entry, cb, smccc_start, smccc_end);
return 0;
}
+static void qcom_link_stack_sanitization(void)
+{
+ u64 tmp;
+
+ asm volatile("mov %0, x30 \n"
+ ".rept 16 \n"
+ "bl . + 4 \n"
+ ".endr \n"
+ "mov x30, %0 \n"
+ : "=&r" (tmp));
+}
+
+static int qcom_enable_link_stack_sanitization(void *data)
+{
+ const struct arm64_cpu_capabilities *entry = data;
+
+ install_bp_hardening_cb(entry, qcom_link_stack_sanitization,
+ __qcom_hyp_sanitize_link_stack_start,
+ __qcom_hyp_sanitize_link_stack_end);
+
+ return 0;
+}
#endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */
#define MIDR_RANGE(model, min, max) \
@@ -390,12 +399,20 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR_V1),
- .enable = enable_smccc_arch_workaround_1,
+ .enable = qcom_enable_link_stack_sanitization,
+ },
+ {
+ .capability = ARM64_HARDEN_BP_POST_GUEST_EXIT,
+ MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR_V1),
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR),
- .enable = enable_smccc_arch_workaround_1,
+ .enable = qcom_enable_link_stack_sanitization,
+ },
+ {
+ .capability = ARM64_HARDEN_BP_POST_GUEST_EXIT,
+ MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR),
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index e41a161d313a..1f458f7c3b44 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -209,3 +209,15 @@ alternative_endif
eret
ENDPROC(__fpsimd_guest_restore)
+
+ENTRY(__qcom_hyp_sanitize_btac_predictors)
+ /**
+ * Call SMC64 with Silicon provider serviceID 23<<8 (0xc2001700)
+ * 0xC2000000-0xC200FFFF: assigned to SiP Service Calls
+ * b15-b0: contains SiP functionID
+ */
+ movz x0, #0x1700
+ movk x0, #0xc200, lsl #16
+ smc #0
+ ret
+ENDPROC(__qcom_hyp_sanitize_btac_predictors)
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index d9645236e474..07b572173265 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -472,6 +472,16 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
/* And we're baaack! */
} while (fixup_guest_exit(vcpu, &exit_code));
+ if (cpus_have_const_cap(ARM64_HARDEN_BP_POST_GUEST_EXIT)) {
+ u32 midr = read_cpuid_id();
+
+ /* Apply BTAC predictors mitigation to all Falkor chips */
+ if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) ||
+ ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)) {
+ __qcom_hyp_sanitize_btac_predictors();
+ }
+ }
+
fp_enabled = __fpsimd_enabled_nvhe();
__sysreg_save_state_nvhe(guest_ctxt);
--
2.14.2
