5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Yazen Ghannam yazen.ghannam@amd.com
[ Upstream commit d66e1e90b16055d2f0ee76e5384e3f119c3c2773 ]
Ensure that sysfs init doesn't fail for new/unrecognized bank types or if a bank has additional blocks available.
Most MCA banks have a single thresholding block, so the block takes the same name as the bank.
Unified Memory Controllers (UMCs) are a special case where there are two blocks and each has a unique name.
However, the microarchitecture allows for five blocks. Any new MCA bank types with more than one block will be missing names for the extra blocks. The MCE sysfs will fail to initialize in this case.
Fixes: 87a6d4091bd7 ("x86/mce/AMD: Update sysfs bank names for SMCA systems") Signed-off-by: Yazen Ghannam yazen.ghannam@amd.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/20250624-wip-mca-updates-v4-3-236dd74f645f@amd.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kernel/cpu/mce/amd.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
--- a/arch/x86/kernel/cpu/mce/amd.c +++ b/arch/x86/kernel/cpu/mce/amd.c @@ -1180,13 +1180,20 @@ static const char *get_name(unsigned int }
bank_type = smca_get_bank_type(bank); - if (bank_type >= N_SMCA_BANK_TYPES) - return NULL;
if (b && bank_type == SMCA_UMC) { if (b->block < ARRAY_SIZE(smca_umc_block_names)) return smca_umc_block_names[b->block]; - return NULL; + } + + if (b && b->block) { + snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN, "th_block_%u", b->block); + return buf_mcatype; + } + + if (bank_type >= N_SMCA_BANK_TYPES) { + snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN, "th_bank_%u", bank); + return buf_mcatype; }
if (smca_banks[bank].hwid->count == 1)