From: Jane Chu jane.chu@oracle.com
[ 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@oracle.com Signed-off-by: Borislav Petkov bp@suse.de Reviewed-by: Dan Williams dan.j.williams@intel.com Reviewed-by: Ingo Molnar mingo@kernel.org Link: https://lore.kernel.org/r/7ed50fd8-521e-cade-77b1-738b8bfb8502@oracle.com Link: https://lore.kernel.org/r/20220826233851.1319100-1-jane.chu@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kernel/cpu/mce/apei.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/mce/apei.c b/arch/x86/kernel/cpu/mce/apei.c index 0e3ae64d3b76..b08b90cdc2a3 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;