* [PATCH 1/4] drm/xe: Add DRM_IOCTL_XE_VM_RESTART IOCTL
2026-06-12 13:53 [RFC PATCH 0/4] Xe driver asynchronous notification mechanism Thomas Hellström
@ 2026-06-12 13:53 ` Thomas Hellström
2026-06-12 13:53 ` [PATCH 2/4] drm/xe: Add fault injection for rebind worker -ENOSPC Thomas Hellström
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Thomas Hellström @ 2026-06-12 13:53 UTC (permalink / raw)
To: intel-xe
Cc: Thomas Hellström, Matthew Brost, Maarten Lankhorst,
Michal Mrozek, John Falkowski, Rodrigo Vivi, Lahtinen Joonas,
David Howells, Christian Brauner, Kees Cook, Davidlohr Bueso,
Christian König, Dave Airlie, Simona Vetter, dri-devel, LMKL
Add an async VM restart IOCTL that allows userspace to re-queue the
preempt-rebind worker for a VM that has been paused after a recoverable
error.
Add xe_vm_restart_ioctl() which:
- Looks up the VM by id via xe_vm_lookup()
- Returns -EINVAL if the VM is not in preempt-fence mode or not restartable
- Returns -EALREADY if the VM is not currently paused
- Queues the rebind worker via and returns 0
If the optional @timestamp_ns field is non-zero, logs the latency
between that timestamp and the point the worker is queued.
Add DRM_XE_VM_CREATE_FLAG_RESTARTABLE to opt a VM in to the restartable
behaviour: on recoverable errors (-ENOMEM, -ENOSPC) the rebind worker
is deactivated rather than the VM being killed. Requires
DRM_XE_VM_CREATE_FLAG_LR_MODE and may not be used with
DRM_XE_VM_CREATE_FLAG_FAULT_MODE.
Add struct drm_xe_vm_restart UAPI struct with vm_id, pad, timestamp_ns
and reserved fields, and register the IOCTL at slot 0x10.
Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index 51e3a2dd7b22..867d7c55dc03 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -215,6 +215,7 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
DRM_RENDER_ALLOW),
DRM_IOCTL_DEF_DRV(XE_VM_GET_PROPERTY, xe_vm_get_property_ioctl,
DRM_RENDER_ALLOW),
+ DRM_IOCTL_DEF_DRV(XE_VM_RESTART, xe_vm_restart_ioctl, DRM_RENDER_ALLOW),
};
static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 75841f3e9afa..86ed8f31a219 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -563,8 +563,14 @@ static void preempt_rebind_work_func(struct work_struct *w)
}
if (err) {
- drm_warn(&vm->xe->drm, "VM worker error: %d\n", err);
- xe_vm_kill(vm, true);
+ if ((err == -ENOMEM || err == -ENOSPC) && xe_vm_is_restartable(vm)) {
+ vm->preempt.rebind_deactivated = true;
+ drm_dbg(&vm->xe->drm, "Rebind deactivated VM on error %pe\n",
+ ERR_PTR(err));
+ } else {
+ drm_warn(&vm->xe->drm, "VM worker error: %d\n", err);
+ xe_vm_kill(vm, true);
+ }
}
up_write(&vm->lock);
@@ -573,6 +579,85 @@ static void preempt_rebind_work_func(struct work_struct *w)
trace_xe_vm_rebind_worker_exit(vm);
}
+/**
+ * xe_vm_restart_ioctl() - Queue the preempt-rebind worker for a paused VM
+ * @dev: DRM device
+ * @data: pointer to &struct drm_xe_vm_restart from userspace
+ * @file: DRM file handle
+ *
+ * Looks up the VM identified by @vm_id and, if it is currently paused (its
+ * rebind worker was deactivated after a recoverable error), clears the paused
+ * state and queues the rebind worker. Only valid for VMs in preempt-fence
+ * mode.
+ *
+ * If @timestamp_ns is non-zero, logs the latency between that timestamp and
+ * the point the vm lock is taken, regardless of whether the VM was paused.
+ *
+ * Return: 0 if the worker was queued, -EALREADY if the VM is not paused,
+ * -EINVAL if the VM is not in preempt-fence mode or not restartable,
+ * -ENOENT if the VM was not found.
+ */
+int xe_vm_restart_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file)
+{
+ struct xe_device *xe = to_xe_device(dev);
+ struct xe_file *xef = to_xe_file(file);
+ struct drm_xe_vm_restart *args = data;
+ struct xe_vm *vm;
+ int err = 0;
+
+ if (XE_IOCTL_DBG(xe, args->reserved || args->pad))
+ return -EINVAL;
+
+ vm = xe_vm_lookup(xef, args->vm_id);
+ if (XE_IOCTL_DBG(xe, !vm))
+ return -ENOENT;
+
+ if (XE_IOCTL_DBG(xe, !xe_vm_in_preempt_fence_mode(vm))) {
+ xe_vm_put(vm);
+ return -EINVAL;
+ }
+
+ if (XE_IOCTL_DBG(xe, !xe_vm_is_restartable(vm))) {
+ xe_vm_put(vm);
+ return -EINVAL;
+ }
+
+ err = down_read_interruptible(&vm->lock);
+ if (err)
+ goto out;
+
+ if (XE_IOCTL_DBG(xe, xe_vm_is_closed_or_banned(vm))) {
+ err = -ENOENT;
+ goto out_unlock_read;
+ }
+
+ if (args->timestamp_ns) {
+ u64 delay_us = (ktime_get_ns() - args->timestamp_ns) / NSEC_PER_USEC;
+
+ drm_dbg(&xe->drm, "VM %u restart latency: %llu us\n",
+ args->vm_id, delay_us);
+ }
+
+ err = xe_vm_lock(vm, true);
+ if (err)
+ goto out_unlock_read;
+
+ if (!vm->preempt.rebind_deactivated) {
+ err = -EALREADY;
+ goto out_unlock_resv;
+ }
+
+ xe_vm_reactivate_rebind(vm);
+out_unlock_resv:
+ xe_vm_unlock(vm);
+out_unlock_read:
+ up_read(&vm->lock);
+out:
+ xe_vm_put(vm);
+ return err;
+}
+
/**
* xe_vm_add_fault_entry_pf() - Add pagefault to vm fault list
* @vm: The VM.
@@ -2049,7 +2134,8 @@ find_ufence_get(struct xe_sync_entry *syncs, u32 num_syncs)
#define ALL_DRM_XE_VM_CREATE_FLAGS (DRM_XE_VM_CREATE_FLAG_SCRATCH_PAGE | \
DRM_XE_VM_CREATE_FLAG_LR_MODE | \
DRM_XE_VM_CREATE_FLAG_FAULT_MODE | \
- DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT)
+ DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT | \
+ DRM_XE_VM_CREATE_FLAG_RESTARTABLE)
int xe_vm_create_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
@@ -2092,6 +2178,11 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
args->flags & DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT))
return -EINVAL;
+ if (XE_IOCTL_DBG(xe, args->flags & DRM_XE_VM_CREATE_FLAG_RESTARTABLE &&
+ (!(args->flags & DRM_XE_VM_CREATE_FLAG_LR_MODE) ||
+ args->flags & DRM_XE_VM_CREATE_FLAG_FAULT_MODE)))
+ return -EINVAL;
+
if (args->flags & DRM_XE_VM_CREATE_FLAG_SCRATCH_PAGE)
flags |= XE_VM_FLAG_SCRATCH_PAGE;
if (args->flags & DRM_XE_VM_CREATE_FLAG_LR_MODE)
@@ -2100,6 +2191,8 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
flags |= XE_VM_FLAG_FAULT_MODE;
if (args->flags & DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT)
flags |= XE_VM_FLAG_NO_VM_OVERCOMMIT;
+ if (args->flags & DRM_XE_VM_CREATE_FLAG_RESTARTABLE)
+ flags |= XE_VM_FLAG_RESTARTABLE;
vm = xe_vm_create(xe, flags, xef);
if (IS_ERR(vm))
diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h
index c5b900f38ded..9ee44599cacd 100644
--- a/drivers/gpu/drm/xe/xe_vm.h
+++ b/drivers/gpu/drm/xe/xe_vm.h
@@ -212,7 +212,8 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data,
int xe_vm_query_vmas_attrs_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
int xe_vm_get_property_ioctl(struct drm_device *dev, void *data,
struct drm_file *file);
-
+int xe_vm_restart_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file);
void xe_vm_close_and_put(struct xe_vm *vm);
static inline bool xe_vm_in_fault_mode(struct xe_vm *vm)
@@ -237,6 +238,11 @@ static inline bool xe_vm_allow_vm_eviction(struct xe_vm *vm)
!(vm->flags & XE_VM_FLAG_NO_VM_OVERCOMMIT));
}
+static inline bool xe_vm_is_restartable(struct xe_vm *vm)
+{
+ return vm->flags & XE_VM_FLAG_RESTARTABLE;
+}
+
int xe_vm_add_compute_exec_queue(struct xe_vm *vm, struct xe_exec_queue *q);
void xe_vm_remove_compute_exec_queue(struct xe_vm *vm, struct xe_exec_queue *q);
diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
index 635ed29b9a69..7d295c3b8456 100644
--- a/drivers/gpu/drm/xe/xe_vm_types.h
+++ b/drivers/gpu/drm/xe/xe_vm_types.h
@@ -264,6 +264,7 @@ struct xe_vm {
#define XE_VM_FLAG_SET_TILE_ID(tile) FIELD_PREP(GENMASK(7, 6), (tile)->id)
#define XE_VM_FLAG_GSC BIT(8)
#define XE_VM_FLAG_NO_VM_OVERCOMMIT BIT(9)
+#define XE_VM_FLAG_RESTARTABLE BIT(10)
unsigned long flags;
/**
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index 48e9f1fdb78d..bebb0167bd31 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -85,6 +85,7 @@ extern "C" {
* - &DRM_IOCTL_XE_VM_QUERY_MEM_RANGE_ATTRS
* - &DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY
* - &DRM_IOCTL_XE_VM_GET_PROPERTY
+ * - &DRM_IOCTL_XE_VM_RESTART
*/
/*
@@ -110,6 +111,7 @@ extern "C" {
#define DRM_XE_VM_QUERY_MEM_RANGE_ATTRS 0x0d
#define DRM_XE_EXEC_QUEUE_SET_PROPERTY 0x0e
#define DRM_XE_VM_GET_PROPERTY 0x0f
+#define DRM_XE_VM_RESTART 0x10
/* Must be kept compact -- no holes */
@@ -129,6 +131,7 @@ extern "C" {
#define DRM_IOCTL_XE_VM_QUERY_MEM_RANGE_ATTRS DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_VM_QUERY_MEM_RANGE_ATTRS, struct drm_xe_vm_query_mem_range_attr)
#define DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY DRM_IOW(DRM_COMMAND_BASE + DRM_XE_EXEC_QUEUE_SET_PROPERTY, struct drm_xe_exec_queue_set_property)
#define DRM_IOCTL_XE_VM_GET_PROPERTY DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_VM_GET_PROPERTY, struct drm_xe_vm_get_property)
+#define DRM_IOCTL_XE_VM_RESTART DRM_IOW(DRM_COMMAND_BASE + DRM_XE_VM_RESTART, struct drm_xe_vm_restart)
/**
* DOC: Xe IOCTL Extensions
@@ -985,6 +988,10 @@ struct drm_xe_gem_mmap_offset {
* but only during a &DRM_IOCTL_XE_VM_BIND operation with the
* %DRM_XE_VM_BIND_FLAG_IMMEDIATE flag set. This may be useful for
* user-space naively probing the amount of available memory.
+ * - %DRM_XE_VM_CREATE_FLAG_RESTARTABLE - Requires also
+ * DRM_XE_VM_CREATE_FLAG_LR_MODE. Marks the VM as restartable, enabling
+ * use of &DRM_IOCTL_XE_VM_RESTART to resume the preempt-rebind worker
+ * after an error has paused it.
*/
struct drm_xe_vm_create {
/** @extensions: Pointer to the first extension struct, if any */
@@ -994,6 +1001,7 @@ struct drm_xe_vm_create {
#define DRM_XE_VM_CREATE_FLAG_LR_MODE (1 << 1)
#define DRM_XE_VM_CREATE_FLAG_FAULT_MODE (1 << 2)
#define DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT (1 << 3)
+#define DRM_XE_VM_CREATE_FLAG_RESTARTABLE (1 << 4)
/** @flags: Flags */
__u32 flags;
@@ -2531,8 +2539,44 @@ struct drm_xe_exec_queue_set_property {
};
/**
- * DOC: Xe DRM RAS
+ * DOC: DRM_XE_VM_RESTART
+ *
+ * Restart a paused VM by queuing its preempt-rebind worker. The VM must be
+ * in preempt-fence mode and must currently be paused (i.e. its rebind worker
+ * was deactivated after a recoverable error such as -ENOMEM or -ENOSPC).
+ *
+ * Returns 0 if the rebind worker was successfully queued. Returns -EALREADY
+ * if the VM is not currently paused. Returns -EINVAL if the VM is not in
+ * preempt-fence mode or not restartable.
*
+ * An optional @timestamp_ns can be provided to measure the latency between
+ * event delivery and the point the worker is queued; the driver logs this
+ * once all sanity checks have passed.
+ */
+
+/**
+ * struct drm_xe_vm_restart - restart a VM's preempt-rebind worker
+ *
+ * Used with %DRM_IOCTL_XE_VM_RESTART.
+ */
+struct drm_xe_vm_restart {
+ /** @vm_id: ID of the VM to restart */
+ __u32 vm_id;
+ /** @pad: reserved, must be zero */
+ __u32 pad;
+ /**
+ * @timestamp_ns: optional CLOCK_MONOTONIC timestamp in nanoseconds.
+ * When non-zero, the driver logs the delay between this timestamp and
+ * the point the vm lock is taken, regardless of whether the VM is
+ * currently paused. Pass zero to disable the logging.
+ */
+ __u64 timestamp_ns;
+ /** @reserved: reserved, must be zero */
+ __u64 reserved;
+};
+
+/**
+ * DOC: Xe DRM RAS
* The enums and strings defined below map to the attributes of the DRM RAS Netlink Interface.
* Refer to Documentation/netlink/specs/drm_ras.yaml for complete interface specification.
*
---
drivers/gpu/drm/xe/xe_device.c | 1 +
drivers/gpu/drm/xe/xe_vm.c | 99 +++++++++++++++++++++++++++++++-
drivers/gpu/drm/xe/xe_vm.h | 8 ++-
drivers/gpu/drm/xe/xe_vm_types.h | 1 +
include/uapi/drm/xe_drm.h | 46 ++++++++++++++-
5 files changed, 150 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index 51e3a2dd7b22..867d7c55dc03 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -215,6 +215,7 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
DRM_RENDER_ALLOW),
DRM_IOCTL_DEF_DRV(XE_VM_GET_PROPERTY, xe_vm_get_property_ioctl,
DRM_RENDER_ALLOW),
+ DRM_IOCTL_DEF_DRV(XE_VM_RESTART, xe_vm_restart_ioctl, DRM_RENDER_ALLOW),
};
static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 75841f3e9afa..86ed8f31a219 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -563,8 +563,14 @@ static void preempt_rebind_work_func(struct work_struct *w)
}
if (err) {
- drm_warn(&vm->xe->drm, "VM worker error: %d\n", err);
- xe_vm_kill(vm, true);
+ if ((err == -ENOMEM || err == -ENOSPC) && xe_vm_is_restartable(vm)) {
+ vm->preempt.rebind_deactivated = true;
+ drm_dbg(&vm->xe->drm, "Rebind deactivated VM on error %pe\n",
+ ERR_PTR(err));
+ } else {
+ drm_warn(&vm->xe->drm, "VM worker error: %d\n", err);
+ xe_vm_kill(vm, true);
+ }
}
up_write(&vm->lock);
@@ -573,6 +579,85 @@ static void preempt_rebind_work_func(struct work_struct *w)
trace_xe_vm_rebind_worker_exit(vm);
}
+/**
+ * xe_vm_restart_ioctl() - Queue the preempt-rebind worker for a paused VM
+ * @dev: DRM device
+ * @data: pointer to &struct drm_xe_vm_restart from userspace
+ * @file: DRM file handle
+ *
+ * Looks up the VM identified by @vm_id and, if it is currently paused (its
+ * rebind worker was deactivated after a recoverable error), clears the paused
+ * state and queues the rebind worker. Only valid for VMs in preempt-fence
+ * mode.
+ *
+ * If @timestamp_ns is non-zero, logs the latency between that timestamp and
+ * the point the vm lock is taken, regardless of whether the VM was paused.
+ *
+ * Return: 0 if the worker was queued, -EALREADY if the VM is not paused,
+ * -EINVAL if the VM is not in preempt-fence mode or not restartable,
+ * -ENOENT if the VM was not found.
+ */
+int xe_vm_restart_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file)
+{
+ struct xe_device *xe = to_xe_device(dev);
+ struct xe_file *xef = to_xe_file(file);
+ struct drm_xe_vm_restart *args = data;
+ struct xe_vm *vm;
+ int err = 0;
+
+ if (XE_IOCTL_DBG(xe, args->reserved || args->pad))
+ return -EINVAL;
+
+ vm = xe_vm_lookup(xef, args->vm_id);
+ if (XE_IOCTL_DBG(xe, !vm))
+ return -ENOENT;
+
+ if (XE_IOCTL_DBG(xe, !xe_vm_in_preempt_fence_mode(vm))) {
+ xe_vm_put(vm);
+ return -EINVAL;
+ }
+
+ if (XE_IOCTL_DBG(xe, !xe_vm_is_restartable(vm))) {
+ xe_vm_put(vm);
+ return -EINVAL;
+ }
+
+ err = down_read_interruptible(&vm->lock);
+ if (err)
+ goto out;
+
+ if (XE_IOCTL_DBG(xe, xe_vm_is_closed_or_banned(vm))) {
+ err = -ENOENT;
+ goto out_unlock_read;
+ }
+
+ if (args->timestamp_ns) {
+ u64 delay_us = (ktime_get_ns() - args->timestamp_ns) / NSEC_PER_USEC;
+
+ drm_dbg(&xe->drm, "VM %u restart latency: %llu us\n",
+ args->vm_id, delay_us);
+ }
+
+ err = xe_vm_lock(vm, true);
+ if (err)
+ goto out_unlock_read;
+
+ if (!vm->preempt.rebind_deactivated) {
+ err = -EALREADY;
+ goto out_unlock_resv;
+ }
+
+ xe_vm_reactivate_rebind(vm);
+out_unlock_resv:
+ xe_vm_unlock(vm);
+out_unlock_read:
+ up_read(&vm->lock);
+out:
+ xe_vm_put(vm);
+ return err;
+}
+
/**
* xe_vm_add_fault_entry_pf() - Add pagefault to vm fault list
* @vm: The VM.
@@ -2049,7 +2134,8 @@ find_ufence_get(struct xe_sync_entry *syncs, u32 num_syncs)
#define ALL_DRM_XE_VM_CREATE_FLAGS (DRM_XE_VM_CREATE_FLAG_SCRATCH_PAGE | \
DRM_XE_VM_CREATE_FLAG_LR_MODE | \
DRM_XE_VM_CREATE_FLAG_FAULT_MODE | \
- DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT)
+ DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT | \
+ DRM_XE_VM_CREATE_FLAG_RESTARTABLE)
int xe_vm_create_ioctl(struct drm_device *dev, void *data,
struct drm_file *file)
@@ -2092,6 +2178,11 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
args->flags & DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT))
return -EINVAL;
+ if (XE_IOCTL_DBG(xe, args->flags & DRM_XE_VM_CREATE_FLAG_RESTARTABLE &&
+ (!(args->flags & DRM_XE_VM_CREATE_FLAG_LR_MODE) ||
+ args->flags & DRM_XE_VM_CREATE_FLAG_FAULT_MODE)))
+ return -EINVAL;
+
if (args->flags & DRM_XE_VM_CREATE_FLAG_SCRATCH_PAGE)
flags |= XE_VM_FLAG_SCRATCH_PAGE;
if (args->flags & DRM_XE_VM_CREATE_FLAG_LR_MODE)
@@ -2100,6 +2191,8 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
flags |= XE_VM_FLAG_FAULT_MODE;
if (args->flags & DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT)
flags |= XE_VM_FLAG_NO_VM_OVERCOMMIT;
+ if (args->flags & DRM_XE_VM_CREATE_FLAG_RESTARTABLE)
+ flags |= XE_VM_FLAG_RESTARTABLE;
vm = xe_vm_create(xe, flags, xef);
if (IS_ERR(vm))
diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h
index c5b900f38ded..9ee44599cacd 100644
--- a/drivers/gpu/drm/xe/xe_vm.h
+++ b/drivers/gpu/drm/xe/xe_vm.h
@@ -212,7 +212,8 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data,
int xe_vm_query_vmas_attrs_ioctl(struct drm_device *dev, void *data, struct drm_file *file);
int xe_vm_get_property_ioctl(struct drm_device *dev, void *data,
struct drm_file *file);
-
+int xe_vm_restart_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file);
void xe_vm_close_and_put(struct xe_vm *vm);
static inline bool xe_vm_in_fault_mode(struct xe_vm *vm)
@@ -237,6 +238,11 @@ static inline bool xe_vm_allow_vm_eviction(struct xe_vm *vm)
!(vm->flags & XE_VM_FLAG_NO_VM_OVERCOMMIT));
}
+static inline bool xe_vm_is_restartable(struct xe_vm *vm)
+{
+ return vm->flags & XE_VM_FLAG_RESTARTABLE;
+}
+
int xe_vm_add_compute_exec_queue(struct xe_vm *vm, struct xe_exec_queue *q);
void xe_vm_remove_compute_exec_queue(struct xe_vm *vm, struct xe_exec_queue *q);
diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
index 635ed29b9a69..7d295c3b8456 100644
--- a/drivers/gpu/drm/xe/xe_vm_types.h
+++ b/drivers/gpu/drm/xe/xe_vm_types.h
@@ -264,6 +264,7 @@ struct xe_vm {
#define XE_VM_FLAG_SET_TILE_ID(tile) FIELD_PREP(GENMASK(7, 6), (tile)->id)
#define XE_VM_FLAG_GSC BIT(8)
#define XE_VM_FLAG_NO_VM_OVERCOMMIT BIT(9)
+#define XE_VM_FLAG_RESTARTABLE BIT(10)
unsigned long flags;
/**
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index 48e9f1fdb78d..bebb0167bd31 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -85,6 +85,7 @@ extern "C" {
* - &DRM_IOCTL_XE_VM_QUERY_MEM_RANGE_ATTRS
* - &DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY
* - &DRM_IOCTL_XE_VM_GET_PROPERTY
+ * - &DRM_IOCTL_XE_VM_RESTART
*/
/*
@@ -110,6 +111,7 @@ extern "C" {
#define DRM_XE_VM_QUERY_MEM_RANGE_ATTRS 0x0d
#define DRM_XE_EXEC_QUEUE_SET_PROPERTY 0x0e
#define DRM_XE_VM_GET_PROPERTY 0x0f
+#define DRM_XE_VM_RESTART 0x10
/* Must be kept compact -- no holes */
@@ -129,6 +131,7 @@ extern "C" {
#define DRM_IOCTL_XE_VM_QUERY_MEM_RANGE_ATTRS DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_VM_QUERY_MEM_RANGE_ATTRS, struct drm_xe_vm_query_mem_range_attr)
#define DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY DRM_IOW(DRM_COMMAND_BASE + DRM_XE_EXEC_QUEUE_SET_PROPERTY, struct drm_xe_exec_queue_set_property)
#define DRM_IOCTL_XE_VM_GET_PROPERTY DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_VM_GET_PROPERTY, struct drm_xe_vm_get_property)
+#define DRM_IOCTL_XE_VM_RESTART DRM_IOW(DRM_COMMAND_BASE + DRM_XE_VM_RESTART, struct drm_xe_vm_restart)
/**
* DOC: Xe IOCTL Extensions
@@ -985,6 +988,10 @@ struct drm_xe_gem_mmap_offset {
* but only during a &DRM_IOCTL_XE_VM_BIND operation with the
* %DRM_XE_VM_BIND_FLAG_IMMEDIATE flag set. This may be useful for
* user-space naively probing the amount of available memory.
+ * - %DRM_XE_VM_CREATE_FLAG_RESTARTABLE - Requires also
+ * DRM_XE_VM_CREATE_FLAG_LR_MODE. Marks the VM as restartable, enabling
+ * use of &DRM_IOCTL_XE_VM_RESTART to resume the preempt-rebind worker
+ * after an error has paused it.
*/
struct drm_xe_vm_create {
/** @extensions: Pointer to the first extension struct, if any */
@@ -994,6 +1001,7 @@ struct drm_xe_vm_create {
#define DRM_XE_VM_CREATE_FLAG_LR_MODE (1 << 1)
#define DRM_XE_VM_CREATE_FLAG_FAULT_MODE (1 << 2)
#define DRM_XE_VM_CREATE_FLAG_NO_VM_OVERCOMMIT (1 << 3)
+#define DRM_XE_VM_CREATE_FLAG_RESTARTABLE (1 << 4)
/** @flags: Flags */
__u32 flags;
@@ -2531,8 +2539,44 @@ struct drm_xe_exec_queue_set_property {
};
/**
- * DOC: Xe DRM RAS
+ * DOC: DRM_XE_VM_RESTART
+ *
+ * Restart a paused VM by queuing its preempt-rebind worker. The VM must be
+ * in preempt-fence mode and must currently be paused (i.e. its rebind worker
+ * was deactivated after a recoverable error such as -ENOMEM or -ENOSPC).
+ *
+ * Returns 0 if the rebind worker was successfully queued. Returns -EALREADY
+ * if the VM is not currently paused. Returns -EINVAL if the VM is not in
+ * preempt-fence mode or not restartable.
*
+ * An optional @timestamp_ns can be provided to measure the latency between
+ * event delivery and the point the worker is queued; the driver logs this
+ * once all sanity checks have passed.
+ */
+
+/**
+ * struct drm_xe_vm_restart - restart a VM's preempt-rebind worker
+ *
+ * Used with %DRM_IOCTL_XE_VM_RESTART.
+ */
+struct drm_xe_vm_restart {
+ /** @vm_id: ID of the VM to restart */
+ __u32 vm_id;
+ /** @pad: reserved, must be zero */
+ __u32 pad;
+ /**
+ * @timestamp_ns: optional CLOCK_MONOTONIC timestamp in nanoseconds.
+ * When non-zero, the driver logs the delay between this timestamp and
+ * the point the vm lock is taken, regardless of whether the VM is
+ * currently paused. Pass zero to disable the logging.
+ */
+ __u64 timestamp_ns;
+ /** @reserved: reserved, must be zero */
+ __u64 reserved;
+};
+
+/**
+ * DOC: Xe DRM RAS
* The enums and strings defined below map to the attributes of the DRM RAS Netlink Interface.
* Refer to Documentation/netlink/specs/drm_ras.yaml for complete interface specification.
*
--
2.54.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 4/4] drm/xe: Add watch_queue-based device event notification
2026-06-12 13:53 [RFC PATCH 0/4] Xe driver asynchronous notification mechanism Thomas Hellström
` (2 preceding siblings ...)
2026-06-12 13:53 ` [PATCH 3/4] watch_queue: Add a DRM_XE_NOTIFY watch type and export init_watch() Thomas Hellström
@ 2026-06-12 13:53 ` Thomas Hellström
3 siblings, 0 replies; 5+ messages in thread
From: Thomas Hellström @ 2026-06-12 13:53 UTC (permalink / raw)
To: intel-xe
Cc: Thomas Hellström, Matthew Brost, Maarten Lankhorst,
Michal Mrozek, John Falkowski, Rodrigo Vivi, Lahtinen Joonas,
David Howells, Christian Brauner, Kees Cook, Davidlohr Bueso,
Christian König, Dave Airlie, Simona Vetter, dri-devel, LMKL
Add a watch_queue notification channel tied to struct xe_file so that
userspace can subscribe to asynchronous GPU device events via the
general kernel notification mechanism.
Introduce DRM_IOCTL_XE_WATCH_QUEUE to let userspace subscribe a
notification pipe (opened with pipe2(O_NOTIFICATION_PIPE)) to the device
event stream. Embed the watch_id field (0-255) in the WATCH_INFO_ID
field of every notification, allowing multiple watches to share a single
pipe and be told apart by the reader.
Deliver notifications as struct drm_xe_watch_notification records, with
type always set to WATCH_TYPE_DRM_XE_NOTIFY and subtype drawn from enum
drm_xe_watch_event. Define DRM_XE_WATCH_EVENT_VM_ERR as the first
event, posted by the preempt-rebind worker when a VM encounters an
unrecoverable error. Expose xe_watch_queue_post_vm_err_event() as the
in-kernel posting API.
Add event definitions in a separate uapi header, <drm/xe_drm_events.h>.
The main reason is that the header needs to include <linux/watch_queue.h>
which in turn includes <linux/fcntl.h> which may conflict with the
system <fcntl.h>. Hence user-space must pay special attention when
including this file.
Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
---
MAINTAINERS | 1 +
drivers/gpu/drm/xe/Kconfig | 1 +
drivers/gpu/drm/xe/Makefile | 1 +
drivers/gpu/drm/xe/xe_device.c | 7 ++
drivers/gpu/drm/xe/xe_device_types.h | 6 ++
drivers/gpu/drm/xe/xe_vm.c | 4 +
drivers/gpu/drm/xe/xe_vm_types.h | 2 +
drivers/gpu/drm/xe/xe_watch_queue.c | 111 +++++++++++++++++++++++++++
drivers/gpu/drm/xe/xe_watch_queue.h | 20 +++++
include/uapi/drm/xe_drm.h | 45 +++++++++++
include/uapi/drm/xe_drm_events.h | 62 +++++++++++++++
11 files changed, 260 insertions(+)
create mode 100644 drivers/gpu/drm/xe/xe_watch_queue.c
create mode 100644 drivers/gpu/drm/xe/xe_watch_queue.h
create mode 100644 include/uapi/drm/xe_drm_events.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 8c0d9965c636..b7e02cfa692b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12900,6 +12900,7 @@ F: Documentation/gpu/xe/
F: drivers/gpu/drm/xe/
F: include/drm/intel/
F: include/uapi/drm/xe_drm.h
+F: include/uapi/drm/xe_drm_events.h
INTEL ELKHART LAKE PSE I/O DRIVER
M: Raag Jadav <raag.jadav@intel.com>
diff --git a/drivers/gpu/drm/xe/Kconfig b/drivers/gpu/drm/xe/Kconfig
index 4d7dcaff2b91..dbdc2fb49c53 100644
--- a/drivers/gpu/drm/xe/Kconfig
+++ b/drivers/gpu/drm/xe/Kconfig
@@ -25,6 +25,7 @@ config DRM_XE
select DRM_MIPI_DSI
select RELAY
select IRQ_WORK
+ select WATCH_QUEUE
# xe depends on ACPI_VIDEO when ACPI is enabled
# but for select to work, need to select ACPI_VIDEO's dependencies, ick
select BACKLIGHT_CLASS_DEVICE if ACPI
diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index 8e7b146880f4..fc8b4023a044 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -150,6 +150,7 @@ xe-y += xe_bb.o \
xe_vsec.o \
xe_wa.o \
xe_wait_user_fence.o \
+ xe_watch_queue.o \
xe_wopcm.o
xe-$(CONFIG_I2C) += xe_i2c.o
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index 867d7c55dc03..788ef2fbd6e5 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -9,6 +9,7 @@
#include <linux/delay.h>
#include <linux/fault-inject.h>
#include <linux/units.h>
+#include <linux/watch_queue.h>
#include <drm/drm_client.h>
#include <drm/drm_gem_ttm_helper.h>
@@ -77,6 +78,7 @@
#include "xe_vsec.h"
#include "xe_wait_user_fence.h"
#include "xe_wa.h"
+#include "xe_watch_queue.h"
#include <generated/xe_device_wa_oob.h>
#include <generated/xe_wa_oob.h>
@@ -112,6 +114,8 @@ static int xe_file_open(struct drm_device *dev, struct drm_file *file)
file->driver_priv = xef;
kref_init(&xef->refcount);
+ init_watch_list(&xef->watch_list, NULL);
+
task = get_pid_task(rcu_access_pointer(file->pid), PIDTYPE_PID);
if (task) {
xef->process_name = kstrdup(task->comm, GFP_KERNEL);
@@ -126,6 +130,8 @@ static void xe_file_destroy(struct kref *ref)
{
struct xe_file *xef = container_of(ref, struct xe_file, refcount);
+ remove_watch_from_object(&xef->watch_list, NULL, 0, true);
+
xa_destroy(&xef->exec_queue.xa);
mutex_destroy(&xef->exec_queue.lock);
xa_destroy(&xef->vm.xa);
@@ -216,6 +222,7 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
DRM_IOCTL_DEF_DRV(XE_VM_GET_PROPERTY, xe_vm_get_property_ioctl,
DRM_RENDER_ALLOW),
DRM_IOCTL_DEF_DRV(XE_VM_RESTART, xe_vm_restart_ioctl, DRM_RENDER_ALLOW),
+ DRM_IOCTL_DEF_DRV(XE_WATCH_QUEUE, xe_watch_queue_ioctl, DRM_RENDER_ALLOW),
};
static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
index 32dd2ffbc796..ca726ada30a7 100644
--- a/drivers/gpu/drm/xe/xe_device_types.h
+++ b/drivers/gpu/drm/xe/xe_device_types.h
@@ -11,6 +11,7 @@
#include <drm/drm_device.h>
#include <drm/drm_file.h>
#include <drm/ttm/ttm_device.h>
+#include <linux/watch_queue.h>
#include "xe_devcoredump_types.h"
#include "xe_drm_ras_types.h"
@@ -632,6 +633,11 @@ struct xe_file {
/** @refcount: ref count of this xe file */
struct kref refcount;
+
+#ifdef CONFIG_WATCH_QUEUE
+ /** @watch_list: per-file notification source for device events */
+ struct watch_list watch_list;
+#endif
};
#endif
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index b69a2e5bd9c9..232de0d948d2 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -13,6 +13,7 @@
#include <drm/drm_print.h>
#include <drm/ttm/ttm_tt.h>
#include <uapi/drm/xe_drm.h>
+#include <uapi/drm/xe_drm_events.h>
#include <linux/ascii85.h>
#include <linux/delay.h>
#include <linux/kthread.h>
@@ -45,6 +46,7 @@
#include "xe_trace_bo.h"
#include "xe_vm_madvise.h"
#include "xe_wa.h"
+#include "xe_watch_queue.h"
#ifdef CONFIG_FAULT_INJECTION
static DECLARE_FAULT_ATTR(rebind_enospc);
@@ -584,6 +586,7 @@ static void preempt_rebind_work_func(struct work_struct *w)
}
if (err) {
+ xe_watch_queue_post_vm_err_event(vm->xef, vm->id, err);
if ((err == -ENOMEM || err == -ENOSPC) && xe_vm_is_restartable(vm)) {
vm->preempt.rebind_deactivated = true;
drm_dbg(&vm->xe->drm, "Rebind deactivated VM on error %pe\n",
@@ -2229,6 +2232,7 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
if (err)
goto err_close_and_put;
+ vm->id = id;
args->vm_id = id;
return 0;
diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
index 7d295c3b8456..19a673099588 100644
--- a/drivers/gpu/drm/xe/xe_vm_types.h
+++ b/drivers/gpu/drm/xe/xe_vm_types.h
@@ -407,6 +407,8 @@ struct xe_vm {
bool batch_invalidate_tlb;
/** @xef: Xe file handle for tracking this VM's drm client */
struct xe_file *xef;
+ /** @id: The id of the VM in the VM table of @xef. */
+ u32 id;
};
/** struct xe_vma_op_map - VMA map operation */
diff --git a/drivers/gpu/drm/xe/xe_watch_queue.c b/drivers/gpu/drm/xe/xe_watch_queue.c
new file mode 100644
index 000000000000..32763591075b
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_watch_queue.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2026 Intel Corporation
+ */
+
+#include <linux/slab.h>
+#include <linux/timekeeping.h>
+#include <linux/watch_queue.h>
+
+#include <uapi/drm/xe_drm.h>
+#include <uapi/drm/xe_drm_events.h>
+
+#include "xe_device.h"
+#include "xe_device_types.h"
+#include "xe_macros.h"
+#include "xe_watch_queue.h"
+
+/**
+ * struct xe_watch_notification_vm_err - kernel-side VM error event notification
+ * @base: common watch notification header; type is %WATCH_TYPE_DRM_XE_NOTIFY,
+ * subtype is %DRM_XE_WATCH_EVENT_VM_ERR
+ * @vm_id: ID of the VM that hit error
+ * @error_code: error code describing the error condition (negative errno)
+ * @timestamp_ns: CLOCK_MONOTONIC timestamp in nanoseconds at the point the
+ * error was detected
+ *
+ * Layout mirrors &struct drm_xe_watch_notification_vm_err.
+ */
+struct xe_watch_notification_vm_err {
+ struct watch_notification base;
+ u32 vm_id;
+ s32 error_code;
+ u64 timestamp_ns;
+};
+
+/**
+ * xe_watch_queue_ioctl() - Subscribe a pipe to per-file device event notifications
+ * @dev: DRM device
+ * @data: pointer to &struct drm_xe_watch_queue from userspace
+ * @file: DRM file handle of the subscribing process
+ *
+ * Subscribes a notification pipe to receive Xe device events for the calling
+ * process's file handle. Only events scoped to this file (e.g. VM error on a
+ * VM owned by this file) are delivered. The pipe must have been opened with
+ * O_NOTIFICATION_PIPE and sized with %IOC_WATCH_QUEUE_SET_SIZE before calling
+ * this IOCTL.
+ *
+ * Return: 0 on success, negative errno on failure.
+ */
+int xe_watch_queue_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
+{
+ struct xe_file *xef = file->driver_priv;
+ struct xe_device *xe = to_xe_device(dev);
+ struct drm_xe_watch_queue *args = data;
+ struct watch_queue *wqueue;
+ struct watch *watch;
+ int ret;
+
+ if (XE_IOCTL_DBG(xe, args->flags || args->pad))
+ return -EINVAL;
+ if (XE_IOCTL_DBG(xe, args->watch_id > 0xff))
+ return -EINVAL;
+
+ wqueue = get_watch_queue(args->fd);
+ if (XE_IOCTL_DBG(xe, IS_ERR(wqueue)))
+ return PTR_ERR(wqueue);
+
+ watch = kzalloc_obj(*watch, GFP_KERNEL | __GFP_ACCOUNT);
+ if (XE_IOCTL_DBG(xe, !watch)) {
+ ret = -ENOMEM;
+ goto out_put_queue;
+ }
+
+ init_watch(watch, wqueue);
+ watch->id = 0;
+ watch->info_id = (u32)args->watch_id << WATCH_INFO_ID__SHIFT;
+
+ ret = add_watch_to_object(watch, &xef->watch_list);
+ if (XE_IOCTL_DBG(xe, ret))
+ kfree(watch);
+
+out_put_queue:
+ put_watch_queue(wqueue);
+ return ret;
+}
+
+/**
+ * xe_watch_queue_post_vm_err_event() - Post a VM error event
+ * @xef: xe file handle that owns the VM
+ * @vm_id: userspace ID of the VM that hit error
+ * @error_code: error code describing the error condition (negative errno)
+ *
+ * Posts a %DRM_XE_WATCH_EVENT_VM_ERR notification carrying @vm_id and
+ * @error_code to every pipe that @xef has subscribed via
+ * %DRM_IOCTL_XE_WATCH_QUEUE. Only the owning process is notified,
+ * preventing information leaks to other clients.
+ */
+void xe_watch_queue_post_vm_err_event(struct xe_file *xef, u32 vm_id,
+ int error_code)
+{
+ struct xe_watch_notification_vm_err n = {};
+
+ n.base.type = WATCH_TYPE_DRM_XE_NOTIFY;
+ n.base.subtype = DRM_XE_WATCH_EVENT_VM_ERR;
+ n.base.info = watch_sizeof(struct xe_watch_notification_vm_err);
+ n.vm_id = vm_id;
+ n.error_code = error_code;
+ n.timestamp_ns = ktime_get_ns();
+
+ post_watch_notification(&xef->watch_list, &n.base, current_cred(), 0);
+}
diff --git a/drivers/gpu/drm/xe/xe_watch_queue.h b/drivers/gpu/drm/xe/xe_watch_queue.h
new file mode 100644
index 000000000000..ad199ee68205
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_watch_queue.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2026 Intel Corporation
+ */
+
+#ifndef _XE_WATCH_QUEUE_H_
+#define _XE_WATCH_QUEUE_H_
+
+#include <linux/types.h>
+
+struct drm_device;
+struct drm_file;
+struct xe_file;
+
+int xe_watch_queue_ioctl(struct drm_device *dev, void *data,
+ struct drm_file *file);
+void xe_watch_queue_post_vm_err_event(struct xe_file *xef, u32 vm_id,
+ int error_code);
+
+#endif /* _XE_WATCH_QUEUE_H_ */
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index 8d5e3f06b8d4..0083dd712f7e 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -86,6 +86,7 @@ extern "C" {
* - &DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY
* - &DRM_IOCTL_XE_VM_GET_PROPERTY
* - &DRM_IOCTL_XE_VM_RESTART
+ * - &DRM_IOCTL_XE_WATCH_QUEUE
*/
/*
@@ -112,6 +113,7 @@ extern "C" {
#define DRM_XE_EXEC_QUEUE_SET_PROPERTY 0x0e
#define DRM_XE_VM_GET_PROPERTY 0x0f
#define DRM_XE_VM_RESTART 0x10
+#define DRM_XE_WATCH_QUEUE 0x11
/* Must be kept compact -- no holes */
@@ -132,6 +134,7 @@ extern "C" {
#define DRM_IOCTL_XE_EXEC_QUEUE_SET_PROPERTY DRM_IOW(DRM_COMMAND_BASE + DRM_XE_EXEC_QUEUE_SET_PROPERTY, struct drm_xe_exec_queue_set_property)
#define DRM_IOCTL_XE_VM_GET_PROPERTY DRM_IOWR(DRM_COMMAND_BASE + DRM_XE_VM_GET_PROPERTY, struct drm_xe_vm_get_property)
#define DRM_IOCTL_XE_VM_RESTART DRM_IOW(DRM_COMMAND_BASE + DRM_XE_VM_RESTART, struct drm_xe_vm_restart)
+#define DRM_IOCTL_XE_WATCH_QUEUE DRM_IOW(DRM_COMMAND_BASE + DRM_XE_WATCH_QUEUE, struct drm_xe_watch_queue)
/**
* DOC: Xe IOCTL Extensions
@@ -2653,6 +2656,48 @@ enum drm_xe_ras_error_component {
[DRM_XE_RAS_ERR_COMP_SOC_INTERNAL] = "soc-internal" \
}
+/**
+ * DOC: DRM_XE_WATCH_QUEUE
+ *
+ * Subscribe a notification pipe to receive device events for the calling
+ * process's DRM file handle. Events are scoped to the subscribing file:
+ * only events that belong to that file (for example, VM error on a VM created
+ * through the same file) are delivered, preventing information leaks between
+ * processes sharing the same GPU device.
+ *
+ * The pipe must first be opened with O_NOTIFICATION_PIPE (i.e. O_EXCL passed
+ * to pipe2()) and sized via %IOC_WATCH_QUEUE_SET_SIZE before subscribing.
+ *
+ * Events are delivered as notification records read from the pipe. The
+ * @watch_id field is embedded in the notification info field and can be used
+ * to distinguish multiple watches sharing a pipe.
+ *
+ * Currently defined event subtypes:
+ * - %DRM_XE_WATCH_EVENT_VM_ERR - a VM owned by this file has encountered an error
+ */
+
+/**
+ * struct drm_xe_watch_queue - subscribe to device event notifications
+ *
+ * Used with %DRM_IOCTL_XE_WATCH_QUEUE. Notifications are scoped to the
+ * DRM file handle used to issue this IOCTL.
+ */
+struct drm_xe_watch_queue {
+ /** @fd: file descriptor of pipe opened with O_NOTIFICATION_PIPE */
+ __u32 fd;
+
+ /**
+ * @watch_id: identifier (0–255) embedded in the watch notification
+ * info field; allows multiplexing several watches on one pipe
+ */
+ __u32 watch_id;
+
+ /** @flags: must be zero */
+ __u32 flags;
+
+ /** @pad: reserved, must be zero */
+ __u32 pad;
+};
#if defined(__cplusplus)
}
#endif
diff --git a/include/uapi/drm/xe_drm_events.h b/include/uapi/drm/xe_drm_events.h
new file mode 100644
index 000000000000..6cc7528bfb9b
--- /dev/null
+++ b/include/uapi/drm/xe_drm_events.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2026 Intel Corporation
+ */
+
+#ifndef _UAPI_XE_DRM_EVENTS_H_
+#define _UAPI_XE_DRM_EVENTS_H_
+
+#include <linux/types.h>
+#include <linux/watch_queue.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+/**
+ * enum drm_xe_watch_event - Xe device watch event subtypes
+ *
+ * Subtypes for notifications delivered via %WATCH_TYPE_DRM_XE_NOTIFY when
+ * reading from a pipe subscribed with %DRM_IOCTL_XE_WATCH_QUEUE.
+ */
+enum drm_xe_watch_event {
+ /**
+ * @DRM_XE_WATCH_EVENT_VM_ERR: a VM has encountered an error.
+ *
+ * Indicates that a fatal or resource error occurred within the given
+ * VM. The vm_id of the affected VM is carried in the
+ * @drm_xe_watch_notification_vm_err::vm_id field of the extended
+ * notification record.
+ */
+ DRM_XE_WATCH_EVENT_VM_ERR = 0,
+};
+
+/**
+ * struct drm_xe_watch_notification_vm_err - VM error event notification
+ *
+ * Notification record delivered for %DRM_XE_WATCH_EVENT_VM_ERR.
+ * The record type is always %WATCH_TYPE_DRM_XE_NOTIFY and the subtype is
+ * %DRM_XE_WATCH_EVENT_VM_ERR.
+ */
+struct drm_xe_watch_notification_vm_err {
+ /** @base: common watch notification header */
+ struct watch_notification base;
+
+ /** @vm_id: ID of the VM that encountered an error */
+ __u32 vm_id;
+
+ /** @error_code: error code describing the error condition (negative errno) */
+ __s32 error_code;
+
+ /**
+ * @timestamp_ns: CLOCK_MONOTONIC timestamp in nanoseconds at the
+ * point the error was detected
+ */
+ __u64 timestamp_ns;
+};
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* _UAPI_XE_DRM_EVENTS_H_ */
--
2.54.0
^ permalink raw reply related [flat|nested] 5+ messages in thread