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 <[email protected]>
---
v1->v2: Add more context in commit message
---
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 3e86772d5fac5..5a2e0232862e0 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -222,6 +222,9 @@ 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);
}
--
2.37.0.rc0.161.g10f37bed90-goog
On Wed, Jul 06, 2022 at 01:16:49AM +0800, Hsin-Yi Wang wrote:
> 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 <[email protected]>
> ---
> v1->v2: Add more context in commit message
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Il 05/07/22 19:16, Hsin-Yi Wang ha scritto:
> 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 <[email protected]>
Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
On Tue, 5 Jul 2022 at 19:17, Hsin-Yi Wang <[email protected]> wrote:
>
> 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 <[email protected]>
Reviewed-by: Ulf Hansson <[email protected]>
Kind regards
Uffe
> ---
> v1->v2: Add more context in commit message
> ---
> 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 3e86772d5fac5..5a2e0232862e0 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -222,6 +222,9 @@ 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);
> }
> --
> 2.37.0.rc0.161.g10f37bed90-goog
>
On Wed, Jul 13, 2022 at 2:02 PM Ulf Hansson <[email protected]> wrote:
>
> On Tue, 5 Jul 2022 at 19:17, Hsin-Yi Wang <[email protected]> wrote:
> >
> > 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 <[email protected]>
>
> Reviewed-by: Ulf Hansson <[email protected]>
Applied as 5.20 material, thanks!
> > ---
> > v1->v2: Add more context in commit message
> > ---
> > 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 3e86772d5fac5..5a2e0232862e0 100644
> > --- a/drivers/base/power/domain.c
> > +++ b/drivers/base/power/domain.c
> > @@ -222,6 +222,9 @@ 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);
> > }
> > --
> > 2.37.0.rc0.161.g10f37bed90-goog
> >