From a6c4da4b95a3cfe4f6031bef2d913331dc186142 Mon Sep 17 00:00:00 2001 From: Leo Yan Date: Mon, 9 Feb 2026 12:44:35 +0000 Subject: [PATCH] coresight: Protect unregistration with mutex The device registration is protected by CoreSight mutex to ensure the atomic operations when adding a device onto bus. One the other hand, the locking is absent when unregister a device. Use mutex to ensure atomicity on device unregistration. During unregistration, unbinding the associated CTI device is not included in the locking region, as CTI has its own locking mechanism. Fixes: 8c1d3f79d9ca ("coresight: core: Fix coresight device probe failure issue") Reviewed-by: James Clark Signed-off-by: Leo Yan Signed-off-by: Suzuki K Poulose Link: https://lore.kernel.org/r/20260209-arm_coresight_refactor_dev_register-v4-3-62d6042f76f7@arm.com --- drivers/hwtracing/coresight/coresight-core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index e2c0f971eccf..c228c27e8517 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1432,14 +1432,17 @@ EXPORT_SYMBOL_GPL(coresight_register); void coresight_unregister(struct coresight_device *csdev) { - etm_perf_del_symlink_sink(csdev); /* Remove references of that device in the topology */ if (cti_assoc_ops && cti_assoc_ops->remove) cti_assoc_ops->remove(csdev); + + mutex_lock(&coresight_mutex); + etm_perf_del_symlink_sink(csdev); coresight_remove_conns(csdev); coresight_clear_default_sink(csdev); coresight_release_platform_data(csdev, csdev->dev.parent, csdev->pdata); device_unregister(&csdev->dev); + mutex_unlock(&coresight_mutex); } EXPORT_SYMBOL_GPL(coresight_unregister); -- 2.47.3