From 834035934cef9e60169de682f4dc9feafd49e51a Mon Sep 17 00:00:00 2001 From: Michael Reeves Date: Tue, 6 Oct 2026 18:03:15 +1100 Subject: [PATCH] regmap: Remove debugfs before cache teardown regmap_exit() and regmap_reinit_cache() destroy the register cache before removing debugfs. A concurrent debugfs cache operation can therefore access cache state after the backend exit callback starts freeing it. Remove debugfs before cache teardown, and clear the debugfs pointer after removal. During cache reinitialization, recreate debugfs only after the new cache initializes successfully. Signed-off-by: Michael Reeves Reviewed-by: Peng Fan Link: https://patch.msgid.link/20261006-regcache-lifecycle-submit-v3-1-37bdd82fd47c@gmail.com Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-debugfs.c | 1 + drivers/base/regmap/regmap.c | 15 +++++++++------ 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 18f1c60749fe..9a09df2ba847 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -664,6 +664,7 @@ void regmap_debugfs_exit(struct regmap *map) { if (map->debugfs) { debugfs_remove_recursive(map->debugfs); + map->debugfs = NULL; mutex_lock(&map->cache_lock); regmap_debugfs_free_dump_cache(map); mutex_unlock(&map->cache_lock); diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index e6e022b02637..8e50a05ff087 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1422,8 +1422,8 @@ int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config) { int ret; - regcache_exit(map); regmap_debugfs_exit(map); + regcache_exit(map); map->max_register = config->max_register; map->max_register_is_set = map->max_register ?: config->max_register_is_0; @@ -1440,12 +1440,16 @@ int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config) if (ret) return ret; - regmap_debugfs_init(map); - map->cache_bypass = false; map->cache_only = false; - return regcache_init(map, config); + ret = regcache_init(map, config); + if (ret) + return ret; + + regmap_debugfs_init(map); + + return 0; } EXPORT_SYMBOL_GPL(regmap_reinit_cache); @@ -1459,9 +1463,8 @@ void regmap_exit(struct regmap *map) struct regmap_async *async; regmap_detach_dev(map->dev, map); - regcache_exit(map); - regmap_debugfs_exit(map); + regcache_exit(map); regmap_range_exit(map); if (map->bus && map->bus->free_context) map->bus->free_context(map->bus_context);