From 984920c893f0e6832351bc03deeb5ef9a42fbdbb Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Wed, 5 Aug 2026 08:59:10 -0700 Subject: [PATCH] perf/cxl: Don't log through pmu.dev in the overflow interrupt handler perf_pmu_unregister() frees pmu->dev without clearing the pointer, and cxl_pmu_probe() orders its devm actions so that teardown runs it before free_irq(). Nothing in between masks the interrupt, and cxl_pmu_event_stop() leaves the overflow status bit set, so an overflow taken just before teardown is still delivered and still reaches the dev_dbg() in the !event branch - by which point info->pmu.dev is freed. Log through info->pmu.parent instead, which is devm-managed and outlives every teardown action. Fixes: 5d7107c72796 ("perf: CXL Performance Monitoring Unit driver") Reported-by: sashiko-bot@kernel.org Closes: https://sashiko.dev/#/patchset/20260715191454.459673-1-dave@stgolabs.net?part=1 Assisted-by: Claude:claude-opus-4-8 Acked-by: Jonathan Cameron Signed-off-by: Dave Jiang Signed-off-by: Will Deacon --- drivers/perf/cxl_pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/perf/cxl_pmu.c b/drivers/perf/cxl_pmu.c index b09006f2bd9f..6cc8217bfd7a 100644 --- a/drivers/perf/cxl_pmu.c +++ b/drivers/perf/cxl_pmu.c @@ -918,7 +918,7 @@ static irqreturn_t cxl_pmu_irq(int irq, void *data) struct perf_event *event = info->hw_events[i]; if (!event) { - dev_dbg(info->pmu.dev, + dev_dbg(info->pmu.parent, "overflow but on non enabled counter %d\n", i); continue; }