[RFC v1 03/19] uprobes: Print warning for missing breakpoint install

[Andi Kleen]

When installing a uprobe break point fails the error is currently
silently ignored. There is no obvious place to return it to, but
at least print a rate-limited warning to make it easier to debug.

Assisted-by: omp:gpt-5.6-luna
Signed-off-by: Andi Kleen <ak@xxxxxxxxxx>
---
 kernel/events/uprobes.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 4287c4ff4c0f..941b52c47858 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1630,7 +1630,13 @@ int uprobe_mmap(struct vm_area_struct *vma)
 		if (!fatal_signal_pending(current) &&
 		    filter_chain(uprobe, vma->vm_mm)) {
 			unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
-			install_breakpoint(uprobe, vma, vaddr);
+			int err = install_breakpoint(uprobe, vma, vaddr);
+
+			if (err)
+				pr_warn_ratelimited(
+					"uprobes: probe %pD+0x%llx failed to install (%d)\n",
+					vma->vm_file,
+					(unsigned long long)uprobe->offset, err);
 		}
 		put_uprobe(uprobe);
 	}
-- 
2.54.0