[tip: x86/urgent] x86/mce: Use idtentry_nmi_enter/exit()

From: tip-bot2 for Thomas Gleixner
Date: Wed Sep 30 2020 - 04:49:46 EST


The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: bc21a291fc11bbd60868c45b9f5a79ceed97fd4e
Gitweb: https://git.kernel.org/tip/bc21a291fc11bbd60868c45b9f5a79ceed97fd4e
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Wed, 30 Sep 2020 10:19:49 +02:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Wed, 30 Sep 2020 10:41:56 +02:00

x86/mce: Use idtentry_nmi_enter/exit()

The recent fix for NMI vs. IRQ state tracking missed to apply the cure
to the MCE handler.

Fixes: ba1f2b2eaa2a ("x86/entry: Fix NMI vs IRQ state tracking")
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/87mu17ism2.fsf@xxxxxxxxxxxxxxxxxxxxxxx
---
arch/x86/kernel/cpu/mce/core.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index f43a78b..fc4f8c0 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1904,6 +1904,8 @@ void (*machine_check_vector)(struct pt_regs *) = unexpected_machine_check;

static __always_inline void exc_machine_check_kernel(struct pt_regs *regs)
{
+ bool irq_state;
+
WARN_ON_ONCE(user_mode(regs));

/*
@@ -1914,7 +1916,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs)
mce_check_crashing_cpu())
return;

- nmi_enter();
+ irq_state = idtentry_enter_nmi(regs);
/*
* The call targets are marked noinstr, but objtool can't figure
* that out because it's an indirect call. Annotate it.
@@ -1925,7 +1927,7 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs)
if (regs->flags & X86_EFLAGS_IF)
trace_hardirqs_on_prepare();
instrumentation_end();
- nmi_exit();
+ idtentry_exit_nmi(regs, irq_state);
}

static __always_inline void exc_machine_check_user(struct pt_regs *regs)