On 11/28/24 21:39, Barnabás Czémán wrote:
Fix NULL pointer check before device_link_del is called. Unable to handle kernel NULL pointer dereference at virtual address 000000000000032c Call trace: device_link_put_kref+0xc/0xb8 device_link_del+0x30/0x48 vfe_pm_domain_off+0x24/0x38 [qcom_camss] vfe_put+0x9c/0xd0 [qcom_camss] vfe_set_power+0x48/0x58 [qcom_camss] pipeline_pm_power_one+0x154/0x158 [videodev] pipeline_pm_power+0x74/0xfc [videodev] v4l2_pipeline_pm_use+0x54/0x90 [videodev] v4l2_pipeline_pm_put+0x14/0x34 [videodev] video_release+0x2c/0x44 [qcom_camss] v4l2_release+0xe4/0xec [videodev] Fixes: eb73facec2c2 ("media: qcom: camss: Use common VFE pm_domain_on/pm_domain_off where applicable") Tested-by: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx> Signed-off-by: Barnabás Czémán <barnabas.czeman@xxxxxxxxxxxxxx> --- Changes in v2: - Add backtrace to the commit message. - Link to v1: https://lore.kernel.org/r/20241122-vfe_pm_domain_off-v1-1-81d18f56563d@xxxxxxxxxxxxxx --- drivers/media/platform/qcom/camss/camss-vfe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c index 80a62ba11295042802cbaec617fb87c492ea6a55..1bf1473331f63b9ab106d21ea263c84d851c8a31 100644 --- a/drivers/media/platform/qcom/camss/camss-vfe.c +++ b/drivers/media/platform/qcom/camss/camss-vfe.c @@ -595,7 +595,7 @@ void vfe_isr_reset_ack(struct vfe_device *vfe) */ void vfe_pm_domain_off(struct vfe_device *vfe) { - if (!vfe->genpd) + if (!vfe->genpd_link) return;device_link_del(vfe->genpd_link);
I object to this change, there might be a problem in the code, however it is not yet identified. vfe->genpd is not NULL, if vfe_pm_domain_on()/vfe_pm_domain_off() are called appropriately, the "fix" does not fix the real problem, it veils it. -- Best wishes, Vladimir
