6.12-stable review patch. If anyone has any objections, please let me know.
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From: Josh Poimboeuf jpoimboe@kernel.org
[ Upstream commit 16ed389227651330879e17bd83d43bd234006722 ]
If the task is not a user thread, there's no user stack to unwind.
Signed-off-by: Josh Poimboeuf jpoimboe@kernel.org Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Link: https://lore.kernel.org/r/20250820180428.930791978@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/events/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index 0339f60e34981..d6a86d8e9e59b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7847,7 +7847,8 @@ struct perf_callchain_entry * perf_callchain(struct perf_event *event, struct pt_regs *regs) { bool kernel = !event->attr.exclude_callchain_kernel; - bool user = !event->attr.exclude_callchain_user; + bool user = !event->attr.exclude_callchain_user && + !(current->flags & (PF_KTHREAD | PF_USER_WORKER)); /* Disallow cross-task user callchains. */ bool crosstask = event->ctx->task && event->ctx->task != current; const u32 max_stack = event->attr.sample_max_stack;