[patch V2 06/20] x86/extable: Provide EX_TYPE_DEFAULT_MCE_SAFE and EX_TYPE_FAULT_MCE_SAFE

[Thomas Gleixner]

Provide exception fixup types which can be used to identify fixups which
allow in kernel #MC recovery and make them invoke the existing handlers.

These will be used at places where #MC recovery is handled correctly by the
caller.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
V2: New patch
---
 arch/x86/include/asm/extable_fixup_types.h |    3 +++
 arch/x86/kernel/cpu/mce/severity.c         |    2 ++
 arch/x86/mm/extable.c                      |    2 ++
 3 files changed, 7 insertions(+)

--- a/arch/x86/include/asm/extable_fixup_types.h
+++ b/arch/x86/include/asm/extable_fixup_types.h
@@ -16,4 +16,7 @@
 #define	EX_TYPE_WRMSR_IN_MCE		10
 #define	EX_TYPE_RDMSR_IN_MCE		11
 
+#define	EX_TYPE_DEFAULT_MCE_SAFE	12
+#define	EX_TYPE_FAULT_MCE_SAFE		13
+
 #endif
--- a/arch/x86/kernel/cpu/mce/severity.c
+++ b/arch/x86/kernel/cpu/mce/severity.c
@@ -278,6 +278,8 @@ static int error_context(struct mce *m,
 		m->kflags |= MCE_IN_KERNEL_COPYIN;
 		fallthrough;
 	case EX_TYPE_FAULT:
+	case EX_TYPE_FAULT_MCE_SAFE:
+	case EX_TYPE_DEFAULT_MCE_SAFE:
 		m->kflags |= MCE_IN_KERNEL_RECOV;
 		return IN_KERNEL_RECOV;
 	default:
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -131,8 +131,10 @@ int fixup_exception(struct pt_regs *regs
 
 	switch (e->type) {
 	case EX_TYPE_DEFAULT:
+	case EX_TYPE_DEFAULT_MCE_SAFE:
 		return ex_handler_default(e, regs);
 	case EX_TYPE_FAULT:
+	case EX_TYPE_FAULT_MCE_SAFE:
 		return ex_handler_fault(e, regs, trapnr);
 	case EX_TYPE_UACCESS:
 		return ex_handler_uaccess(e, regs, trapnr);