FAILED: patch "[PATCH] panic: flatten nmi_panic control flow" 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 75eb687ff2bcec9fba31bbe266e5f91e5c283efe
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '[email protected]' --subject-prefix 'PATCH 5.15.y' 'HEAD^..'

Thanks,
Sasha

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

From 75eb687ff2bcec9fba31bbe266e5f91e5c283efe Mon Sep 17 00:00:00 2001
From: Bradley Morgan <[email protected]>
Date: Wed, 16 Sep 2026 18:29:53 +0000
Subject: [PATCH] panic: flatten nmi_panic control flow

panic() is __noreturn, so the else after panic_try_start() is dead. Drop it so the force_cpu path can be added cleanly on top.

---
 kernel/panic.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index 08072bfae4221..5646d4fb82b7d 100644
@@ -517,7 +517,8 @@ void nmi_panic(struct pt_regs *regs, const char *msg)
 {
 	if (panic_try_start())
 		panic("%s", msg);
-	else if (panic_on_other_cpu())
+
+	if (panic_on_other_cpu())
 		nmi_panic_self_stop(regs);
 }
 EXPORT_SYMBOL(nmi_panic);

2.53.0

From: Bradley Morgan <[email protected]>

[ Upstream commit 75eb687ff2bcec9fba31bbe266e5f91e5c283efe ]

panic() is __noreturn, so the else after panic_try_start() is dead. Drop it so the force_cpu path can be added cleanly on top.

---
 kernel/panic.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index 3b14c6d123ddc..2db714911168b 100644
@@ -195,7 +195,8 @@ void nmi_panic(struct pt_regs *regs, const char *msg)
 
 	if (old_cpu == PANIC_CPU_INVALID)
 		panic("%s", msg);
-	else if (old_cpu != cpu)
+
+	if (old_cpu != cpu)
 		nmi_panic_self_stop(regs);
 }
 EXPORT_SYMBOL(nmi_panic);

2.53.0