[tip: ras/core] x86/mce: Use mce_rdmsrl() in severity checking code

["tip-bot2 for Borislav Petkov" <tip-bot2@xxxxxxxxxxxxx>]

The following commit has been merged into the ras/core branch of tip:

Commit-ID:     88f66a42353717e7fac31caf04f0acd2d7fbbf54
Gitweb:        https://git.kernel.org/tip/88f66a42353717e7fac31caf04f0acd2d7fbbf54
Author:        Borislav Petkov <bp@xxxxxxx>
AuthorDate:    Wed, 06 Oct 2021 00:55:38 +02:00
Committer:     Borislav Petkov <bp@xxxxxxx>
CommitterDate: Mon, 13 Dec 2021 14:12:08 +01:00

x86/mce: Use mce_rdmsrl() in severity checking code

MCA has its own special MSR accessors. Use them.

No functional changes.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/20211208111343.8130-4-bp@xxxxxxxxx
---
 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 f15efa2..87a277f 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -362,7 +362,7 @@ 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 acd61c4..52c6339 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 bb019a5..00e97eb 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;