Receiving an MMU fault currently disables the AS, so each of the groups
is marked with the appropriate faults. Since no further submissions
can occur on a fatal fault for that group, the fault information
does not have to be cleared until the group is terminated.
Signed-off-by: Lukas Zapolskas <lukas.zapolskas@arm.com>
---
drivers/gpu/drm/panthor/panthor_mmu.c | 8 ++++++++
drivers/gpu/drm/panthor/panthor_mmu.h | 2 ++
drivers/gpu/drm/panthor/panthor_sched.c | 13 +++++++++++++
3 files changed, 23 insertions(+)
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
index 10a7418eecda..9e78b0509f1a 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -2895,3 +2895,11 @@ void panthor_mmu_pt_cache_fini(void)
{
kmem_cache_destroy(pt_cache);
}
+
+struct panthor_vm_fault *panthor_vm_get_fault(struct panthor_vm *vm)
+{
+ if (!vm)
+ return NULL;
+
+ return &vm->fault;
+}
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.h b/drivers/gpu/drm/panthor/panthor_mmu.h
index 023fdc79c231..d69b4000a39e 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.h
+++ b/drivers/gpu/drm/panthor/panthor_mmu.h
@@ -123,4 +123,6 @@ void panthor_mmu_pt_cache_fini(void);
void panthor_mmu_debugfs_init(struct drm_minor *minor);
#endif
+struct panthor_vm_fault *panthor_vm_get_fault(struct panthor_vm *vm);
+
#endif
diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index a77399e95620..9ea0d2b27114 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -722,6 +722,11 @@ struct panthor_group {
* panthor_group::groups::waiting list.
*/
struct list_head wait_node;
+
+ /**
+ * @fatal: VM-level fault that caused a fatal error on the group.
+ */
+ struct panthor_vm_fault fatal;
};
struct panthor_job_profiling_data {
@@ -1575,6 +1580,14 @@ cs_slot_process_fatal_event_locked(struct panthor_device *ptdev,
group->task_info.pid, group->task_info.comm);
group->fatal_queues |= BIT(cs_id);
+
+ if (panthor_vm_has_unhandled_faults(group->vm)) {
+ struct panthor_vm_fault *fault;
+
+ fault = panthor_vm_get_fault(group->vm);
+ if (fault)
+ group->fatal = *fault;
+ }
}
if (CS_EXCEPTION_TYPE(fatal) == DRM_PANTHOR_EXCEPTION_CS_UNRECOVERABLE) {
--
2.33.0.dirty
On Mon, 15 Dec 2025 11:54:56 +0000
Lukas Zapolskas <lukas.zapolskas@arm.com> wrote:
> group->task_info.pid, group->task_info.comm);
>
> group->fatal_queues |= BIT(cs_id);
> +
> + if (panthor_vm_has_unhandled_faults(group->vm)) {
> + struct panthor_vm_fault *fault;
> +
> + fault = panthor_vm_get_fault(group->vm);
> + if (fault)
> + group->fatal = *fault;
group->vm can't be NULL, meaning fault can't be NULL either.
> + }
> }
On Mon, 15 Dec 2025 11:54:56 +0000
Lukas Zapolskas <lukas.zapolskas@arm.com> wrote:
> Receiving an MMU fault currently disables the AS, so each of the groups
> is marked with the appropriate faults. Since no further submissions
> can occur on a fatal fault for that group, the fault information
> does not have to be cleared until the group is terminated.
>
> Signed-off-by: Lukas Zapolskas <lukas.zapolskas@arm.com>
> ---
> drivers/gpu/drm/panthor/panthor_mmu.c | 8 ++++++++
> drivers/gpu/drm/panthor/panthor_mmu.h | 2 ++
> drivers/gpu/drm/panthor/panthor_sched.c | 13 +++++++++++++
> 3 files changed, 23 insertions(+)
>
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
> index 10a7418eecda..9e78b0509f1a 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.c
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.c
> @@ -2895,3 +2895,11 @@ void panthor_mmu_pt_cache_fini(void)
> {
> kmem_cache_destroy(pt_cache);
> }
> +
> +struct panthor_vm_fault *panthor_vm_get_fault(struct panthor_vm *vm)
const struct panthor_vm_fault *
panthor_vm_get_fault(struct panthor_vm *vm)
or
struct panthor_vm_fault
panthor_vm_get_fault(struct panthor_vm *vm)
or
void
panthor_vm_get_fault(struct panthor_vm *vm,
struct panthor_vm_fault *fault)
but you shouldn't let the caller with a writable pointer to vm->fault.
> +{
> + if (!vm)
> + return NULL;
I don't see a valid case where panthor_vm_get_fault() would be called
with a NULL pointer.
> +
> + return &vm->fault;
> +}
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.h b/drivers/gpu/drm/panthor/panthor_mmu.h
> index 023fdc79c231..d69b4000a39e 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.h
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.h
> @@ -123,4 +123,6 @@ void panthor_mmu_pt_cache_fini(void);
> void panthor_mmu_debugfs_init(struct drm_minor *minor);
> #endif
>
> +struct panthor_vm_fault *panthor_vm_get_fault(struct panthor_vm *vm);
> +
> #endif
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> index a77399e95620..9ea0d2b27114 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -722,6 +722,11 @@ struct panthor_group {
> * panthor_group::groups::waiting list.
> */
> struct list_head wait_node;
> +
> + /**
> + * @fatal: VM-level fault that caused a fatal error on the group.
> + */
> + struct panthor_vm_fault fatal;
> };
>
> struct panthor_job_profiling_data {
> @@ -1575,6 +1580,14 @@ cs_slot_process_fatal_event_locked(struct panthor_device *ptdev,
> group->task_info.pid, group->task_info.comm);
>
> group->fatal_queues |= BIT(cs_id);
> +
> + if (panthor_vm_has_unhandled_faults(group->vm)) {
> + struct panthor_vm_fault *fault;
> +
> + fault = panthor_vm_get_fault(group->vm);
> + if (fault)
> + group->fatal = *fault;
> + }
> }
>
> if (CS_EXCEPTION_TYPE(fatal) == DRM_PANTHOR_EXCEPTION_CS_UNRECOVERABLE) {
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