FAILED: patch "[PATCH] x86/mce/amd: Add default names for MCA banks and blocks" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x d66e1e90b16055d2f0ee76e5384e3f119c3c2773
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025071200-cone-ogle-b45b@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d66e1e90b16055d2f0ee76e5384e3f119c3c2773 Mon Sep 17 00:00:00 2001
From: Yazen Ghannam <[email protected]>
Date: Tue, 24 Jun 2025 14:15:58 +0000
Subject: [PATCH] x86/mce/amd: Add default names for MCA banks and blocks

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.

index 9d852c3b2cb5..6820ebce5d46 100644
@@ -1113,13 +1113,20 @@ static const char *get_name(unsigned int cpu, unsigned int bank, struct threshol
 	}
 
 	bank_type = smca_get_bank_type(cpu, bank);
-	if (bank_type >= N_SMCA_BANK_TYPES)
-		return NULL;
 
 	if (b && (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2)) {
 		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 (per_cpu(smca_bank_counts, cpu)[bank_type] == 1)

From: Yazen Ghannam <[email protected]>

[ 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.

---
 arch/x86/kernel/cpu/mce/amd.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

index aa20b2c6881e9..ef8a28343ffb7 100644
@@ -1228,13 +1228,20 @@ static const char *get_name(unsigned int bank, struct threshold_block *b)
 	}
 
 	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)

2.39.5