From: Hsin-Yi Wang hsinyi@chromium.org
[ Upstream commit 37101d3c719386040ded735a5ec06974f1d94d1f ]
Both genpd_debug_add() and genpd_debug_remove() may be called indirectly by other drivers while genpd_debugfs_dir is not yet set. For example, drivers can call pm_genpd_init() in probe or pm_genpd_init() in probe fail/cleanup path:
pm_genpd_init() --> genpd_debug_add()
pm_genpd_remove() --> genpd_remove() --> genpd_debug_remove()
At this time, genpd_debug_init() may not yet be called.
genpd_debug_add() checks that if genpd_debugfs_dir is NULL, it will return directly. Make sure this is also checked in pm_genpd_remove(), otherwise components under debugfs root which has the same name as other components under pm_genpd may be accidentally removed, since NULL represents debugfs root.
Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains") Signed-off-by: Hsin-Yi Wang hsinyi@chromium.org Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/base/power/domain.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 0f2e42f36851..7f3d21e6fdfb 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -219,6 +219,9 @@ static void genpd_debug_remove(struct generic_pm_domain *genpd) { struct dentry *d;
+ if (!genpd_debugfs_dir) + return; + d = debugfs_lookup(genpd->name, genpd_debugfs_dir); debugfs_remove(d); }