[PATCH v0 03/12] x86/mce: Use mce_rdmsrl() in severity checking code

Borislav Petkov
2021-11-04T14:40:55Z

MCA has its own special MSR accessors. Use them.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
---
arch/x86/kernel/cpu/mce/core.c | 2 +-
arch/x86/kernel/cpu/mce/internal.h | 2 ++
arch/x86/kernel/cpu/mce/severity.c | 8 +++-----
3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 0dcd7ac7444c..c660008ccd4a 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -365,7 +365,7 @@ void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr)
}

/* MSR access wrappers used for error injection */
-static noinstr u64 mce_rdmsrl(u32 msr)
+noinstr u64 mce_rdmsrl(u32 msr)
{
DECLARE_ARGS(val, low, high);

diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h
index acd61c41846c..52c633950b38 100644
--- a/arch/x86/kernel/cpu/mce/internal.h
+++ b/arch/x86/kernel/cpu/mce/internal.h
@@ -207,4 +207,6 @@ static inline void pentium_machine_check(struct pt_regs *regs) {}
static inline void winchip_machine_check(struct pt_regs *regs) {}
#endif

+noinstr u64 mce_rdmsrl(u32 msr);
+
#endif /* __X86_MCE_INTERNAL_H__ */
diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c
index bb019a594a2c..00e97ebbd94a 100644
--- a/arch/x86/kernel/cpu/mce/severity.c
+++ b/arch/x86/kernel/cpu/mce/severity.c
@@ -288,8 +288,7 @@ static int error_context(struct mce *m, struct pt_regs *regs)

static int mce_severity_amd_smca(struct mce *m, enum context err_ctx)
{
- u32 addr = MSR_AMD64_SMCA_MCx_CONFIG(m->bank);
- u32 low, high;
+ u64 mcx_cfg;

/*
* We need to look at the following bits:
@@ -300,11 +299,10 @@ static int mce_severity_amd_smca(struct mce *m, enum context err_ctx)
if (!mce_flags.succor)
return MCE_PANIC_SEVERITY;

- if (rdmsr_safe(addr, &low, &high))
- return MCE_PANIC_SEVERITY;
+ mcx_cfg = mce_rdmsrl(MSR_AMD64_SMCA_MCx_CONFIG(m->bank));

/* TCC (Task context corrupt). If set and if IN_KERNEL, panic. */
- if ((low & MCI_CONFIG_MCAX) &&
+ if ((mcx_cfg & MCI_CONFIG_MCAX) &&
(m->status & MCI_STATUS_TCC) &&
(err_ctx == IN_KERNEL))
return MCE_PANIC_SEVERITY;
--
2.29.2