[PATCH v3 01/17] x86/mce: Don't remove sysfs if thresholding sysfs init fails

From: Yazen Ghannam
Date: Tue Apr 15 2025 - 10:56:06 EST


Currently, the MCE subsystem sysfs interface will be removed if the
thresholding sysfs interface fails to be created. A common failure is
due to new MCA bank types that are not recognized and don't have a short
name set.

The MCA thresholding feature is optional and should not break the common
MCE sysfs interface. Also, new MCA bank types are occasionally
introduced, and updates will be needed to recognize them. But likewise,
this should not break the common sysfs interface.

Keep the MCE sysfs interface regardless of the status of the
thresholding sysfs interface.

Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
Tested-by: Tony Luck <tony.luck@xxxxxxxxx>
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---

Notes:
Link:
https://lore.kernel.org/r/20250213-wip-mca-updates-v2-1-3636547fe05f@xxxxxxx

v2->v3:
* Added tags from Qiuxu and Tony.

v1->v2:
* New in v2.
* Included stable tag but there's no specific commit for Fixes.

arch/x86/kernel/cpu/mce/core.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 255927f0284e..72c2aa0809c0 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -2801,15 +2801,9 @@ static int mce_cpu_dead(unsigned int cpu)
static int mce_cpu_online(unsigned int cpu)
{
struct timer_list *t = this_cpu_ptr(&mce_timer);
- int ret;

mce_device_create(cpu);
-
- ret = mce_threshold_create_device(cpu);
- if (ret) {
- mce_device_remove(cpu);
- return ret;
- }
+ mce_threshold_create_device(cpu);
mce_reenable_cpu();
mce_start_timer(t);
return 0;

--
2.49.0