[RESEND PATCH v4 10/11] 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: [email protected]
Closes: https://sashiko.dev/#/patchset/[email protected]?part=1
Assisted-by: Claude:claude-opus-4-8
Acked-by: Jonathan Cameron <[email protected]>
Signed-off-by: Dave Jiang <[email protected]>
---
v4:
- Split the probe-time overflow clear out, so this is back to the single
  hunk Jonathan acked in v2.
---
 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 84ebc7da181d..45edef53a983 100644
--- a/drivers/perf/cxl_pmu.c
+++ b/drivers/perf/cxl_pmu.c
@@ -805,7 +805,7 @@ 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;
 		}
-- 
2.54.0