[PATCH v2 0/1] AMD VM crashing on deferred memory error injection

From: “William Roche

Date: Wed Feb 18 2026 - 11:31:07 EST


From: William Roche <william.roche@xxxxxxxxxx>

Thank you very much Yazen for your review and all the suggestions!

v2 changes:
- Commit title changed to:
x86/mce/amd: Fix VM crash during deferred error handling
- Commit message with capitalized QEMU and KVM as well as the imperative
statement suggested by Yazen
- "CC stable" tag placed after "Signed-off-by"
(The documentation asks for "the sign-off area" without more details)
- blank line added to separate SCMA code block and the update of
MCA_STATUS.

--

After the integration of the following commit:
7cb735d7c0cb x86/mce: Unify AMD DFR handler with MCA Polling

AMD Qemu VM started to crash when dealing with deferred memory error
injection with a stack trace like:

mce: MSR access error: WRMSR to 0xc0002098 (tried to write 0x0000000000000000)
at rIP: 0xffffffff8229894d (mce_wrmsrq+0x1d/0x60)

amd_clear_bank+0x6e/0x70
machine_check_poll+0x228/0x2e0
? __pfx_mce_timer_fn+0x10/0x10
mce_timer_fn+0xb1/0x130
? __pfx_mce_timer_fn+0x10/0x10
call_timer_fn+0x26/0x120
__run_timers+0x202/0x290
run_timer_softirq+0x49/0x100
handle_softirqs+0xeb/0x2c0
__irq_exit_rcu+0xda/0x100
sysvec_apic_timer_interrupt+0x71/0x90
[...]
Kernel panic - not syncing: MCA architectural violation!

See the discussion at:
https://lore.kernel.org/all/48d8e1c8-1eb9-49cc-8de8-78077f29c203@xxxxxxxxxx/

We identified a problem with SMCA specific registers access from
non-SMCA platforms like a QEMU/KVM machine.

This patch is checkpatch.pl clean.
Unit test of memory error injection works fine with it.


William Roche (1):
x86/mce/amd: Fix VM crash during deferred error handling

arch/x86/kernel/cpu/mce/amd.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

--
2.47.3