On Fri, Jun 13, 2025 at 03:43:45PM -0300, André Almeida wrote: > When a device get wedged, it might be caused by a guilty application. > For userspace, knowing which task was involved can be useful for some > situations, like for implementing a policy, logs or for giving a chance > for the compositor to let the user know what task was involved in the > problem. This is an optional argument, when the task info is not > available, the PID and TASK string won't appear in the event string. > > Sometimes just the PID isn't enough giving that the task might be already > dead by the time userspace will try to check what was this PID's name, > so to make the life easier also notify what's the task's name in the user > event. > > Acked-by: Rodrigo Vivi <[email protected]> (for i915 and xe) > Reviewed-by: Krzysztof Karas <[email protected]> > Reviewed-by: Raag Jadav <[email protected]>
Although I'm okay with this version, a few aesthetic nits below. > Signed-off-by: André Almeida <[email protected]> ... > diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c > index 56dd61f8e05a..eba99a081ec1 100644 > --- a/drivers/gpu/drm/drm_drv.c > +++ b/drivers/gpu/drm/drm_drv.c > @@ -538,10 +538,15 @@ static const char *drm_get_wedge_recovery(unsigned int > opt) > } > } > > +#define WEDGE_STR_LEN 32 > +#define PID_STR_LEN 15 > +#define COMM_STR_LEN (TASK_COMM_LEN + 5) Align the values using tabs for readability, and since you're using TASK_COMM_LEN here please include sched.h instead of relying on intermediate header which may not guarantee it for other archs and randconfigs. > + > /** > * drm_dev_wedged_event - generate a device wedged uevent > * @dev: DRM device > * @method: method(s) to be used for recovery > + * @info: optional information about the guilty task > * > * This generates a device wedged uevent for the DRM device specified by > @dev. > * Recovery @method\(s) of choice will be sent in the uevent environment as > @@ -554,13 +559,13 @@ static const char *drm_get_wedge_recovery(unsigned int > opt) > * > * Returns: 0 on success, negative error code otherwise. > */ > -int drm_dev_wedged_event(struct drm_device *dev, unsigned long method) > +int drm_dev_wedged_event(struct drm_device *dev, unsigned long method, > + struct drm_wedge_task_info *info) > { > const char *recovery = NULL; > unsigned int len, opt; > - /* Event string length up to 28+ characters with available methods */ > - char event_string[32]; > - char *envp[] = { event_string, NULL }; > + char event_string[WEDGE_STR_LEN], pid_string[PID_STR_LEN], > comm_string[COMM_STR_LEN]; > + char *envp[] = { event_string, NULL, NULL, NULL }; Let's make this reverse xmas order and be consistent with other helpers in this file. > len = scnprintf(event_string, sizeof(event_string), "%s", "WEDGED="); > > @@ -582,6 +587,13 @@ int drm_dev_wedged_event(struct drm_device *dev, > unsigned long method) > drm_info(dev, "device wedged, %s\n", method == DRM_WEDGE_RECOVERY_NONE ? > "but recovered through reset" : "needs recovery"); > > + if (info && (info->comm[0] != '\0') && (info->pid >= 0)) { > + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid); > + snprintf(comm_string, sizeof(comm_string), "TASK=%s", > info->comm); > + envp[1] = pid_string; > + envp[2] = comm_string; > + } > + > return kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp); > } > EXPORT_SYMBOL(drm_dev_wedged_event); ... > diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h > index e2f894f1b90a..729e1c6da138 100644 > --- a/include/drm/drm_device.h > +++ b/include/drm/drm_device.h > @@ -30,6 +30,14 @@ struct pci_controller; > #define DRM_WEDGE_RECOVERY_REBIND BIT(1) /* unbind + bind driver */ > #define DRM_WEDGE_RECOVERY_BUS_RESET BIT(2) /* unbind + reset bus device + > bind */ > > +/** > + * struct drm_wedge_task_info - information about the guilty task of a wedge > dev > + */ > +struct drm_wedge_task_info { > + pid_t pid; > + char comm[TASK_COMM_LEN]; Ditto for sched.h. Raag > +}; > + > /** > * enum switch_power_state - power state of drm device > */ > diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h > index 63b51942d606..3f76a32d6b84 100644 > --- a/include/drm/drm_drv.h > +++ b/include/drm/drm_drv.h > @@ -487,7 +487,8 @@ void drm_put_dev(struct drm_device *dev); > bool drm_dev_enter(struct drm_device *dev, int *idx); > void drm_dev_exit(int idx); > void drm_dev_unplug(struct drm_device *dev); > -int drm_dev_wedged_event(struct drm_device *dev, unsigned long method); > +int drm_dev_wedged_event(struct drm_device *dev, unsigned long method, > + struct drm_wedge_task_info *info); > > /** > * drm_dev_is_unplugged - is a DRM device unplugged > -- > 2.49.0 >
