The following commit has been merged into the x86/paravirt branch of tip:
Commit-ID: c3d7fa6684b5b3a07a48fc379d27bfb8a96661d9
Gitweb: https://git.kernel.org/tip/c3d7fa6684b5b3a07a48fc379d27bfb8a96661d9
Author: Juergen Gross <jgross@xxxxxxxx>
AuthorDate: Wed, 20 Jan 2021 14:55:42 +01:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Wed, 10 Feb 2021 12:07:10 +01:00
x86/xen: Use specific Xen pv interrupt entry for MCE
Xen PV guests don't use IST. For machine check interrupts, switch to the
same model as debug interrupts.
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20210120135555.32594-3-jgross@xxxxxxxx
---
arch/x86/include/asm/idtentry.h | 3 +++
arch/x86/xen/enlighten_pv.c | 16 +++++++++++++++-
arch/x86/xen/xen-asm.S | 2 +-
3 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index f656aab..616909e 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -585,6 +585,9 @@ DECLARE_IDTENTRY_MCE(X86_TRAP_MC, exc_machine_check);
#else
DECLARE_IDTENTRY_RAW(X86_TRAP_MC, exc_machine_check);
#endif
+#ifdef CONFIG_XEN_PV
+DECLARE_IDTENTRY_RAW(X86_TRAP_MC, xenpv_exc_machine_check);
+#endif
#endif
/* NMI */
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 9a5a50c..9db1d31 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -590,6 +590,20 @@ DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
BUG();
}
+#ifdef CONFIG_X86_MCE
+DEFINE_IDTENTRY_RAW(xenpv_exc_machine_check)
+{
+ /*
+ * There's no IST on Xen PV, but we still need to dispatch
+ * to the correct handler.
+ */
+ if (user_mode(regs))
+ noist_exc_machine_check(regs);
+ else
+ exc_machine_check(regs);
+}
+#endif
+
struct trap_array_entry {
void (*orig)(void);
void (*xen)(void);
@@ -610,7 +624,7 @@ static struct trap_array_entry trap_array[] = {
TRAP_ENTRY_REDIR(exc_debug, true ),
TRAP_ENTRY(exc_double_fault, true ),
#ifdef CONFIG_X86_MCE
- TRAP_ENTRY(exc_machine_check, true ),
+ TRAP_ENTRY_REDIR(exc_machine_check, true ),
#endif
TRAP_ENTRY_REDIR(exc_nmi, true ),
TRAP_ENTRY(exc_int3, false ),
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
index 53cf8aa..cd330ce 100644
--- a/arch/x86/xen/xen-asm.S
+++ b/arch/x86/xen/xen-asm.S
@@ -172,7 +172,7 @@ xen_pv_trap asm_exc_spurious_interrupt_bug
xen_pv_trap asm_exc_coprocessor_error
xen_pv_trap asm_exc_alignment_check
#ifdef CONFIG_X86_MCE
-xen_pv_trap asm_exc_machine_check
+xen_pv_trap asm_xenpv_exc_machine_check
#endif /* CONFIG_X86_MCE */
xen_pv_trap asm_exc_simd_coprocessor_error
#ifdef CONFIG_IA32_EMULATION
|