When a device get wedged, it might be caused by a guilty application.
For userspace, knowing which app was the cause 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 app caused the problem.
This is an optional argument, when `PID=-1` there's no information about
the app caused the problem, or if any app was involved during the hang.
Sometimes just the PID isn't enough giving that the app 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 app's name in the user
event.
Signed-off-by: André Almeida <andrealmeid@igalia.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 2 +-
drivers/gpu/drm/drm_drv.c | 16 +++++++++++++---
drivers/gpu/drm/i915/gt/intel_reset.c | 3 ++-
drivers/gpu/drm/xe/xe_device.c | 3 ++-
include/drm/drm_device.h | 8 ++++++++
include/drm/drm_drv.h | 3 ++-
7 files changed, 29 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 7f354cd532dc..c8a51418d0e7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -6216,7 +6216,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
atomic_set(&adev->reset_domain->reset_res, r);
if (!r)
- drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE);
+ drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE, NULL);
return r;
}
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index acb21fc8b3ce..a47b2eb301e5 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -166,7 +166,7 @@ static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
if (amdgpu_ring_sched_ready(ring))
drm_sched_start(&ring->sched, 0);
dev_err(adev->dev, "Ring %s reset succeeded\n", ring->sched.name);
- drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE);
+ drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE, NULL);
goto exit;
}
dev_err(adev->dev, "Ring %s reset failure\n", ring->sched.name);
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 3dc7acd56b1d..1816ef4251e7 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -542,6 +542,7 @@ static const char *drm_get_wedge_recovery(unsigned int opt)
* 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 app
*
* 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 +555,14 @@ 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_app_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[32], pid_string[15], comm_string[TASK_COMM_LEN];
+ char *envp[] = { event_string, pid_string, comm_string, NULL };
len = scnprintf(event_string, sizeof(event_string), "%s", "WEDGED=");
@@ -582,6 +584,14 @@ 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) {
+ snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
+ snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
+ } else {
+ snprintf(pid_string, sizeof(pid_string), "%s", "PID=-1");
+ snprintf(comm_string, sizeof(comm_string), "%s", "APP=none");
+ }
+
return kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
}
EXPORT_SYMBOL(drm_dev_wedged_event);
diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
index dbdcfe130ad4..ba1d8fdc3c7b 100644
--- a/drivers/gpu/drm/i915/gt/intel_reset.c
+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
@@ -1448,7 +1448,8 @@ static void intel_gt_reset_global(struct intel_gt *gt,
kobject_uevent_env(kobj, KOBJ_CHANGE, reset_done_event);
else
drm_dev_wedged_event(>->i915->drm,
- DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET);
+ DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET,
+ NULL);
}
/**
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index c02c4c4e9412..f329613e061f 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -1168,7 +1168,8 @@ void xe_device_declare_wedged(struct xe_device *xe)
/* Notify userspace of wedged device */
drm_dev_wedged_event(&xe->drm,
- DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET);
+ DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET,
+ NULL);
}
for_each_gt(gt, xe, id)
diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
index e2f894f1b90a..b87401d5079e 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_app_info - information about the guilty app of a wedge dev
+ */
+struct drm_wedge_app_info {
+ pid_t pid;
+ char *comm;
+};
+
/**
* enum switch_power_state - power state of drm device
*/
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index a43d707b5f36..8fc6412a6345 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -482,7 +482,8 @@ 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_app_info *info);
/**
* drm_dev_is_unplugged - is a DRM device unplugged
--
2.49.0
On Sun, May 11, 2025 at 07:47:43PM -0300, André Almeida wrote:
> When a device get wedged, it might be caused by a guilty application.
> For userspace, knowing which app was the cause 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 app caused the problem.
> This is an optional argument, when `PID=-1` there's no information about
> the app caused the problem, or if any app was involved during the hang.
>
> Sometimes just the PID isn't enough giving that the app 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 app's name in the user
> event.
>
> Signed-off-by: André Almeida <andrealmeid@igalia.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +-
> drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 2 +-
> drivers/gpu/drm/drm_drv.c | 16 +++++++++++++---
> drivers/gpu/drm/i915/gt/intel_reset.c | 3 ++-
> drivers/gpu/drm/xe/xe_device.c | 3 ++-
> include/drm/drm_device.h | 8 ++++++++
> include/drm/drm_drv.h | 3 ++-
> 7 files changed, 29 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 7f354cd532dc..c8a51418d0e7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -6216,7 +6216,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
> atomic_set(&adev->reset_domain->reset_res, r);
>
> if (!r)
> - drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE);
> + drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE, NULL);
>
> return r;
> }
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> index acb21fc8b3ce..a47b2eb301e5 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
> @@ -166,7 +166,7 @@ static enum drm_gpu_sched_stat amdgpu_job_timedout(struct drm_sched_job *s_job)
> if (amdgpu_ring_sched_ready(ring))
> drm_sched_start(&ring->sched, 0);
> dev_err(adev->dev, "Ring %s reset succeeded\n", ring->sched.name);
> - drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE);
> + drm_dev_wedged_event(adev_to_drm(adev), DRM_WEDGE_RECOVERY_NONE, NULL);
> goto exit;
> }
> dev_err(adev->dev, "Ring %s reset failure\n", ring->sched.name);
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 3dc7acd56b1d..1816ef4251e7 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -542,6 +542,7 @@ static const char *drm_get_wedge_recovery(unsigned int opt)
> * 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 app
> *
> * 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 +555,14 @@ 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_app_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[32], pid_string[15], comm_string[TASK_COMM_LEN];
> + char *envp[] = { event_string, pid_string, comm_string, NULL };
>
> len = scnprintf(event_string, sizeof(event_string), "%s", "WEDGED=");
>
> @@ -582,6 +584,14 @@ 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) {
> + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
> + snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
> + } else {
> + snprintf(pid_string, sizeof(pid_string), "%s", "PID=-1");
> + snprintf(comm_string, sizeof(comm_string), "%s", "APP=none");
> + }
> +
> return kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
> }
> EXPORT_SYMBOL(drm_dev_wedged_event);
> diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
> index dbdcfe130ad4..ba1d8fdc3c7b 100644
> --- a/drivers/gpu/drm/i915/gt/intel_reset.c
> +++ b/drivers/gpu/drm/i915/gt/intel_reset.c
> @@ -1448,7 +1448,8 @@ static void intel_gt_reset_global(struct intel_gt *gt,
> kobject_uevent_env(kobj, KOBJ_CHANGE, reset_done_event);
> else
> drm_dev_wedged_event(>->i915->drm,
> - DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET);
> + DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET,
> + NULL);
(For future) I believe we can later modify the gt_reset handles here
to get ctx->id when we are coming from reset paths with context and
NULL when we don't have pid.
Perhaps one possibility could be strings to make this flexible
'pid:%d'
'path:debugfs'
But just a brainstorm kind of idea... not a strong feeling or need.
> }
>
> /**
> diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
> index c02c4c4e9412..f329613e061f 100644
> --- a/drivers/gpu/drm/xe/xe_device.c
> +++ b/drivers/gpu/drm/xe/xe_device.c
> @@ -1168,7 +1168,8 @@ void xe_device_declare_wedged(struct xe_device *xe)
>
> /* Notify userspace of wedged device */
> drm_dev_wedged_event(&xe->drm,
> - DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET);
> + DRM_WEDGE_RECOVERY_REBIND | DRM_WEDGE_RECOVERY_BUS_RESET,
> + NULL);
similarly here, for the paths where we come to the wedge declaration from
exeq_queue, we could get q->vm->xef->pid...
But again, no blocker from my side. For both i915 and Xe:
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> }
>
> for_each_gt(gt, xe, id)
> diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
> index e2f894f1b90a..b87401d5079e 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_app_info - information about the guilty app of a wedge dev
> + */
> +struct drm_wedge_app_info {
> + pid_t pid;
> + char *comm;
> +};
> +
> /**
> * enum switch_power_state - power state of drm device
> */
> diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
> index a43d707b5f36..8fc6412a6345 100644
> --- a/include/drm/drm_drv.h
> +++ b/include/drm/drm_drv.h
> @@ -482,7 +482,8 @@ 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_app_info *info);
>
> /**
> * drm_dev_is_unplugged - is a DRM device unplugged
> --
> 2.49.0
>
Hi André,
[...]
> @@ -582,6 +584,14 @@ 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) {
> + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
> + snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
> + } else {
> + snprintf(pid_string, sizeof(pid_string), "%s", "PID=-1");
> + snprintf(comm_string, sizeof(comm_string), "%s", "APP=none");
I think using PID=-1 and APP=none might be misleading, because
something did cause the wedge if we landed here. You could use
"PID=unknown" and "APP=unknown" or ensure these arrays are
zeroed and fill them only if "info" is available:
- char *envp[] = { event_string, NULL };
+ char pid_string[15] = {}, comm_string[TASK_COMM_LEN] = {};
+ char *envp[] = { event_string, pid_string, comm_string, NULL };
[...]
+ if (info) {
+ snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
+ snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
+ }
Then, when printing the logs later you could check if they have
a value and only use them if they do (or handle that however
you would see fit :) ).
Best Regards,
Krzysztof
On 5/12/25 08:08, Krzysztof Karas wrote:
> Hi André,
>
> [...]
>
>> @@ -582,6 +584,14 @@ 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) {
>> + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
>> + snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
>> + } else {
>> + snprintf(pid_string, sizeof(pid_string), "%s", "PID=-1");
>> + snprintf(comm_string, sizeof(comm_string), "%s", "APP=none");
>
> I think using PID=-1 and APP=none might be misleading, because
> something did cause the wedge if we landed here.
Yeah, that certainly won't fly. 1 is a perfectly valid pid.
I would just set pid_string and comm_string to empty if info isn't available.
Regards,
Christian.
You could use
> "PID=unknown" and "APP=unknown" or ensure these arrays are
> zeroed and fill them only if "info" is available:
>
> - char *envp[] = { event_string, NULL };
> + char pid_string[15] = {}, comm_string[TASK_COMM_LEN] = {};
> + char *envp[] = { event_string, pid_string, comm_string, NULL };
>
> [...]
>
> + if (info) {
> + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
> + snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
> + }
>
> Then, when printing the logs later you could check if they have
> a value and only use them if they do (or handle that however
> you would see fit :) ).
>
> Best Regards,
> Krzysztof
Hi Krzysztof,
Thanks for the feedback.
Em 12/05/2025 03:08, Krzysztof Karas escreveu:
> Hi André,
>
> [...]
>
>> @@ -582,6 +584,14 @@ 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) {
>> + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
>> + snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
>> + } else {
>> + snprintf(pid_string, sizeof(pid_string), "%s", "PID=-1");
>> + snprintf(comm_string, sizeof(comm_string), "%s", "APP=none");
>
> I think using PID=-1 and APP=none might be misleading, because
> something did cause the wedge if we landed here. You could use
> "PID=unknown" and "APP=unknown" or ensure these arrays are
> zeroed and fill them only if "info" is available:
>
> - char *envp[] = { event_string, NULL };
> + char pid_string[15] = {}, comm_string[TASK_COMM_LEN] = {};
> + char *envp[] = { event_string, pid_string, comm_string, NULL };
>
> [...]
>
> + if (info) {
> + snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid);
> + snprintf(comm_string, sizeof(comm_string), "APP=%s", info->comm);
> + }
>
> Then, when printing the logs later you could check if they have
> a value and only use them if they do (or handle that however
> you would see fit :) ).
>
That works for me, I will address this in my v3.
Thanks!
> Best Regards,
> Krzysztof
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