There is no reason to have nmi_enter/exit() in the actual MCE
handlers. Move it to the entry point. This also covers the until now
uncovered initial handler which only prints.
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
---
arch/x86/kernel/cpu/mce/core.c | 26 +++++++++++++-------------
arch/x86/kernel/cpu/mce/p5.c | 4 ----
arch/x86/kernel/cpu/mce/winchip.c | 4 ----
3 files changed, 13 insertions(+), 21 deletions(-)
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1100,8 +1100,10 @@ static void mce_clear_state(unsigned lon
* kdump kernel establishing a new #MC handler where a broadcasted MCE
* might not get handled properly.
*/
-static bool __mc_check_crashing_cpu(int cpu)
+static noinstr bool mce_check_crashing_cpu(void)
{
+ unsigned int cpu = smp_processor_id();
+
if (cpu_is_offline(cpu) ||
(crashing_cpu != -1 && crashing_cpu != cpu)) {
u64 mcgstatus;
@@ -1235,7 +1237,6 @@ void noinstr do_machine_check(struct pt_
DECLARE_BITMAP(valid_banks, MAX_NR_BANKS);
DECLARE_BITMAP(toclear, MAX_NR_BANKS);
struct mca_config *cfg = &mca_cfg;
- int cpu = smp_processor_id();
struct mce m, *final;
char *msg = NULL;
int worst = 0;
@@ -1264,11 +1265,6 @@ void noinstr do_machine_check(struct pt_
*/
int lmce = 1;
- if (__mc_check_crashing_cpu(cpu))
- return;
-
- nmi_enter();
-
this_cpu_inc(mce_exception_count);
mce_gather_info(&m, regs);
@@ -1356,7 +1352,7 @@ void noinstr do_machine_check(struct pt_
sync_core();
if (worst != MCE_AR_SEVERITY && !kill_it)
- goto out_ist;
+ return;
/* Fault was in user mode and we need to take some action */
if ((m.cs & 3) == 3) {
@@ -1373,9 +1369,6 @@ void noinstr do_machine_check(struct pt_
if (!fixup_exception(regs, X86_TRAP_MC, error_code, 0))
mce_panic("Failed kernel mode recovery", &m, msg);
}
-
-out_ist:
- nmi_exit();
}
EXPORT_SYMBOL_GPL(do_machine_check);
@@ -1912,11 +1905,18 @@ static void unexpected_machine_check(str
void (*machine_check_vector)(struct pt_regs *, long error_code) =
unexpected_machine_check;
-dotraplinkage notrace void do_mce(struct pt_regs *regs, long error_code)
+dotraplinkage noinstr void do_mce(struct pt_regs *regs, long error_code)
{
+ if (machine_check_vector == do_machine_check &&
+ mce_check_crashing_cpu())
+ return;
+
+ nmi_enter();
+
machine_check_vector(regs, error_code);
+
+ nmi_exit();
}
-NOKPROBE_SYMBOL(do_mce);
/*
* Called for each booted CPU to set up machine checks.
--- a/arch/x86/kernel/cpu/mce/p5.c
+++ b/arch/x86/kernel/cpu/mce/p5.c
@@ -25,8 +25,6 @@ static void pentium_machine_check(struct
{
u32 loaddr, hi, lotype;
- nmi_enter();
-
rdmsr(MSR_IA32_P5_MC_ADDR, loaddr, hi);
rdmsr(MSR_IA32_P5_MC_TYPE, lotype, hi);
@@ -39,8 +37,6 @@ static void pentium_machine_check(struct
}
add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
-
- nmi_exit();
}
/* Set up machine check reporting for processors with Intel style MCE: */
--- a/arch/x86/kernel/cpu/mce/winchip.c
+++ b/arch/x86/kernel/cpu/mce/winchip.c
@@ -19,12 +19,8 @@
/* Machine check handler for WinChip C6: */
static void winchip_machine_check(struct pt_regs *regs, long error_code)
{
- nmi_enter();
-
pr_emerg("CPU0: Machine Check Exception.\n");
add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
-
- nmi_exit();
}
/* Set up machine check reporting on the Winchip C6 series */
