From b6c7b5bb01a1a55c37ee251b177778447fae23cb Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Tue, 12 Mar 2024 19:01:49 +0100 Subject: [PATCH] perf: Move irq_work_queue() where the event is prepared. BugLink: https://bugs.launchpad.net/bugs/2060704 Only if perf_event::pending_sigtrap is zero, the irq_work accounted by increminging perf_event::nr_pending. The member perf_event::pending_addr might be overwritten by a subsequent event if the signal was not yet delivered and is expected. The irq_work will not be enqeueued again because it has a check to be only enqueued once. Move irq_work_queue() to where the counter is incremented and perf_event::pending_sigtrap is set to make it more obvious that the irq_work is scheduled once. Tested-by: Marco Elver Tested-by: Arnaldo Carvalho de Melo Reported-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20240312180814.3373778-2-bigeasy@linutronix.de Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Kevin Becker --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 52b4dd109959..0fded5c79456 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -9653,6 +9653,7 @@ static int __perf_event_overflow(struct perf_event *event, if (!event->pending_sigtrap) { event->pending_sigtrap = pending_id; local_inc(&event->ctx->nr_pending); + irq_work_queue(&event->pending_irq); } else if (event->attr.exclude_kernel && valid_sample) { /* * Should not be able to return to user space without @@ -9672,7 +9673,6 @@ static int __perf_event_overflow(struct perf_event *event, event->pending_addr = 0; if (valid_sample && (data->sample_flags & PERF_SAMPLE_ADDR)) event->pending_addr = data->addr; - irq_work_queue(&event->pending_irq); } READ_ONCE(event->overflow_handler)(event, data, regs);