This is a note to let you know that I've just added the patch titled
x86/mce: Retrieve poison range from hardware
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-mce-retrieve-poison-range-from-hardware.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ea6e74d108bd1eef0d7d8b1ab7b60326e1e2e36b
Author: Jane Chu <jane.chu@xxxxxxxxxx>
Date: Fri Aug 26 17:38:51 2022 -0600
x86/mce: Retrieve poison range from hardware
[ Upstream commit f9781bb18ed828e7b83b7bac4a4ad7cd497ee7d7 ]
When memory poison consumption machine checks fire, MCE notifier
handlers like nfit_handle_mce() record the impacted physical address
range which is reported by the hardware in the MCi_MISC MSR. The error
information includes data about blast radius, i.e. how many cachelines
did the hardware determine are impacted. A recent change
7917f9cdb503 ("acpi/nfit: rely on mce->misc to determine poison granularity")
updated nfit_handle_mce() to stop hard coding the blast radius value of
1 cacheline, and instead rely on the blast radius reported in 'struct
mce' which can be up to 4K (64 cachelines).
It turns out that apei_mce_report_mem_error() had a similar problem in
that it hard coded a blast radius of 4K rather than reading the blast
radius from the error information. Fix apei_mce_report_mem_error() to
convey the proper poison granularity.
Signed-off-by: Jane Chu <jane.chu@xxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/7ed50fd8-521e-cade-77b1-738b8bfb8502@xxxxxxxxxx
Link: https://lore.kernel.org/r/20220826233851.1319100-1-jane.chu@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kernel/cpu/mce/apei.c b/arch/x86/kernel/cpu/mce/apei.c
index 717192915f28..8ed341714686 100644
--- a/arch/x86/kernel/cpu/mce/apei.c
+++ b/arch/x86/kernel/cpu/mce/apei.c
@@ -29,15 +29,26 @@
void apei_mce_report_mem_error(int severity, struct cper_sec_mem_err *mem_err)
{
struct mce m;
+ int lsb;
if (!(mem_err->validation_bits & CPER_MEM_VALID_PA))
return;
+ /*
+ * Even if the ->validation_bits are set for address mask,
+ * to be extra safe, check and reject an error radius '0',
+ * and fall back to the default page size.
+ */
+ if (mem_err->validation_bits & CPER_MEM_VALID_PA_MASK)
+ lsb = find_first_bit((void *)&mem_err->physical_addr_mask, PAGE_SHIFT);
+ else
+ lsb = PAGE_SHIFT;
+
mce_setup(&m);
m.bank = -1;
/* Fake a memory read error with unknown channel */
m.status = MCI_STATUS_VAL | MCI_STATUS_EN | MCI_STATUS_ADDRV | MCI_STATUS_MISCV | 0x9f;
- m.misc = (MCI_MISC_ADDR_PHYS << 6) | PAGE_SHIFT;
+ m.misc = (MCI_MISC_ADDR_PHYS << 6) | lsb;
if (severity >= GHES_SEV_RECOVERABLE)
m.status |= MCI_STATUS_UC;
