Subject: [PATCH v2 4/4] powerpc/xive: Add warning if target CPU not found

From: Shrikanth Hegde <[email-masked]>
Date: Mon, 27 Apr 2026 10:17:15 +0530

Add a warn_once to warn if the CPU target is not found. This could help
to find about any such usecase.

This is a very rare case, which either means mask was empty or
atomic update failed for all online CPUs. So it is worth printing that
path for potential fix.

Signed-off-by: Shrikanth Hegde <[email-masked]>
---
 arch/powerpc/sysdev/xive/common.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c
index c120be73d149..dadd1f46ec93 100644
--- a/arch/powerpc/sysdev/xive/common.c
+++ b/arch/powerpc/sysdev/xive/common.c
@@ -564,6 +564,7 @@ static int xive_find_target_in_mask(const struct cpumask *mask,
 			return cpu;
 	}
 
+	WARN_ONCE(1, "target CPU not found in mask: %*pbl\n", cpumask_pr_args(mask));
 	return -1;
 }
 
-- 
2.47.3