| Message ID | 20241231190336.423172-1-lkundrak@v3.sk (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | clk: mmp2: call pm_genpd_init() only after genpd.name is set | expand |
Quoting Lubomir Rintel (2024-12-31 11:03:35) > Setting the genpd's struct device's name with dev_set_name() is > happening within pm_genpd_init(). If it remains NULL, things can blow up > later, such as when crafting the devfs hierarchy for the power domain: > > 8<--- cut here --- [please do not actually cut, you'll ruin your display] Applied to clk-fixes
Quoting Lubomir Rintel (2024-12-31 11:03:35) > Setting the genpd's struct device's name with dev_set_name() is > happening within pm_genpd_init(). If it remains NULL, things can blow up > later, such as when crafting the devfs hierarchy for the power domain: > > 8<--- cut here --- [please do not actually cut, you'll ruin your display] > Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read > ... > Call trace: > strlen from start_creating+0x90/0x138 > start_creating from debugfs_create_dir+0x20/0x178 > debugfs_create_dir from genpd_debug_add.part.0+0x4c/0x144 > genpd_debug_add.part.0 from genpd_debug_init+0x74/0x90 > genpd_debug_init from do_one_initcall+0x5c/0x244 > do_one_initcall from kernel_init_freeable+0x19c/0x1f4 > kernel_init_freeable from kernel_init+0x1c/0x12c > kernel_init from ret_from_fork+0x14/0x28 > > Bisecting tracks this crash back to commit 899f44531fe6 ("pmdomain: core: > Add GENPD_FLAG_DEV_NAME_FW flag"), which exchanges use of genpd->name > with dev_name(&genpd->dev) in genpd_debug_add.part(). > > Fixes: 899f44531fe6 ("pmdomain: core: Add GENPD_FLAG_DEV_NAME_FW flag") > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Please tell me which author domain it is supposed to be. redhat.com or v3.sk?
On Tue, Jan 7, 2025 at 10:37 PM Stephen Boyd <sboyd@kernel.org> wrote: > > Quoting Lubomir Rintel (2024-12-31 11:03:35) > > Setting the genpd's struct device's name with dev_set_name() is > > happening within pm_genpd_init(). If it remains NULL, things can blow up > > later, such as when crafting the devfs hierarchy for the power domain: > > > > 8<--- cut here --- [please do not actually cut, you'll ruin your display] > > Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read > > ... > > Call trace: > > strlen from start_creating+0x90/0x138 > > start_creating from debugfs_create_dir+0x20/0x178 > > debugfs_create_dir from genpd_debug_add.part.0+0x4c/0x144 > > genpd_debug_add.part.0 from genpd_debug_init+0x74/0x90 > > genpd_debug_init from do_one_initcall+0x5c/0x244 > > do_one_initcall from kernel_init_freeable+0x19c/0x1f4 > > kernel_init_freeable from kernel_init+0x1c/0x12c > > kernel_init from ret_from_fork+0x14/0x28 > > > > Bisecting tracks this crash back to commit 899f44531fe6 ("pmdomain: core: > > Add GENPD_FLAG_DEV_NAME_FW flag"), which exchanges use of genpd->name > > with dev_name(&genpd->dev) in genpd_debug_add.part(). > > > > Fixes: 899f44531fe6 ("pmdomain: core: Add GENPD_FLAG_DEV_NAME_FW flag") > > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> > > Please tell me which author domain it is supposed to be. redhat.com or > v3.sk? lkundrak@v3.sk please My apologies -- apparently gmail now insists on using a gmail address for mail outgoing via their server, to the point it silently rewrites it in messages. I'm also unable to use a different mail server from some networks. Sigh. I'm sorry about this, I'll try to find a way around it next time. Thank you, Lubo
diff --git a/drivers/clk/mmp/pwr-island.c b/drivers/clk/mmp/pwr-island.c index edaa2433a472..eaf5d2c5e593 100644 --- a/drivers/clk/mmp/pwr-island.c +++ b/drivers/clk/mmp/pwr-island.c @@ -106,10 +106,10 @@ struct generic_pm_domain *mmp_pm_domain_register(const char *name, pm_domain->flags = flags; pm_domain->lock = lock; - pm_genpd_init(&pm_domain->genpd, NULL, true); pm_domain->genpd.name = name; pm_domain->genpd.power_on = mmp_pm_domain_power_on; pm_domain->genpd.power_off = mmp_pm_domain_power_off; + pm_genpd_init(&pm_domain->genpd, NULL, true); return &pm_domain->genpd; }
Setting the genpd's struct device's name with dev_set_name() is happening within pm_genpd_init(). If it remains NULL, things can blow up later, such as when crafting the devfs hierarchy for the power domain: 8<--- cut here --- [please do not actually cut, you'll ruin your display] Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read ... Call trace: strlen from start_creating+0x90/0x138 start_creating from debugfs_create_dir+0x20/0x178 debugfs_create_dir from genpd_debug_add.part.0+0x4c/0x144 genpd_debug_add.part.0 from genpd_debug_init+0x74/0x90 genpd_debug_init from do_one_initcall+0x5c/0x244 do_one_initcall from kernel_init_freeable+0x19c/0x1f4 kernel_init_freeable from kernel_init+0x1c/0x12c kernel_init from ret_from_fork+0x14/0x28 Bisecting tracks this crash back to commit 899f44531fe6 ("pmdomain: core: Add GENPD_FLAG_DEV_NAME_FW flag"), which exchanges use of genpd->name with dev_name(&genpd->dev) in genpd_debug_add.part(). Fixes: 899f44531fe6 ("pmdomain: core: Add GENPD_FLAG_DEV_NAME_FW flag") Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> Cc: stable@vger.kernel.org # v6.12+ --- drivers/clk/mmp/pwr-island.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)