[PATCH v3] accel/ivpu: Defer recovery until probe completes

[Karol Wachowski <karol.wachowski@linux.intel.com>]

An error IRQ that fires after ivpu_boot() enables interrupts queues
recovery_work during probe. If probe then fails, the device is torn
down while the work runs, and the work faults on the unmapped BARs:

  BUG: unable to handle page fault for address: ffffcfc6680200f4
  Workqueue: events_unbound ivpu_pm_recovery_work [intel_vpu]
  RIP: 0010:ivpu_hw_ip_ipc_rx_addr_get+0xc/0xb0 [intel_vpu]
  Call Trace:
   ivpu_wait_for_ready+0x155/0x220 [intel_vpu]
   ivpu_boot+0x9e/0x270 [intel_vpu]
   ivpu_resume+0xa4/0xd0 [intel_vpu]
   ivpu_pm_reset_complete+0x2c/0x90 [intel_vpu]
   ivpu_pm_recovery_work+0xf6/0x140 [intel_vpu]

If probe succeeds, the recovery runs concurrently with the rest of
probe, and its pm_runtime_disable() discards the initial autosuspend
request, leaving the NPU active until first use. Any recovery that
starts while the NPU is idle loses the pending autosuspend the same way.

Keep recovery_work disabled from ivpu_pm_init() until ivpu_pm_enable().
A trigger during probe still runs diagnostics and masks interrupts, and
ivpu_pm_enable() runs the deferred recovery before the initial
autosuspend request. A trigger racing with ivpu_pm_enable() can cause
a second, harmless recovery. Request autosuspend at the end of
ivpu_pm_reset_complete() so the NPU suspends again after every reset.

Fixes: 852be13f3bd3 ("accel/ivpu: Add PM support")
Cc: stable@vger.kernel.org
Reported-by: Daksh Sahni <swizzguy76@gmail.com>
Closes: https://lore.kernel.org/r/20261107174215.15818-1-swizzguy76@gmail.com
Signed-off-by: Karol Wachowski <karol.wachowski@linux.intel.com>
---

Notes:
    v3:
    - Request autosuspend at the end of ivpu_pm_reset_complete().
      pm_runtime_disable() in ivpu_pm_reset_begin() cancels a pending
      autosuspend request and pm_runtime_enable() does not re-issue it, so
      a recovery racing with the initial autosuspend request in
      ivpu_pm_enable() left the NPU active until first use (Sashiko).
      A trigger racing with ivpu_pm_enable() can still queue recovery
      twice. The second run is a full reset that leaves the device in a
      consistent state, and autosuspend is now re-requested after each
      reset.
    - Replace pm_runtime_mark_last_busy() with pm_request_autosuspend() in
      ivpu_pm_reset_complete(); it marks the device busy itself.
    - Shorten the commit message.
    - v2: https://lore.kernel.org/r/20261110085003.3527014-1-karol.wachowski@linux.intel.com

    v2:
    - Rework of Daksh's "accel/ivpu: Disable recovery work on probe failure":
      https://lore.kernel.org/r/20261107174215.15818-1-swizzguy76@gmail.com
    - Keep recovery_work disabled from ivpu_pm_init() until ivpu_pm_enable()
      instead of disabling it on the probe error path, which is too late as
      recovery may already run concurrently with ivpu_boot() (Sashiko)
    - Run a recovery requested during probe from ivpu_pm_enable() and wait
      for it before the initial autosuspend request, so the NPU is reset
      before use and the autosuspend is not lost when probe succeeds

    v1:
    - Link: https://lore.kernel.org/r/20261107174215.15818-1-swizzguy76@gmail.com

 drivers/accel/ivpu/ivpu_pm.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/accel/ivpu/ivpu_pm.c b/drivers/accel/ivpu/ivpu_pm.c
index aa813262253e..e4b79c946ca0 100644
--- a/drivers/accel/ivpu/ivpu_pm.c
+++ b/drivers/accel/ivpu/ivpu_pm.c
@@ -150,8 +150,8 @@ static void ivpu_pm_reset_complete(struct ivpu_device *vdev)
 	up_write(&vdev->pm->reset_lock);
 	atomic_set(&vdev->pm->reset_pending, 0);
 
-	pm_runtime_mark_last_busy(vdev->drm.dev);
 	pm_runtime_enable(vdev->drm.dev);
+	pm_request_autosuspend(vdev->drm.dev);
 }
 
 static void ivpu_pm_recovery_work(struct work_struct *work)
@@ -415,6 +415,7 @@ void ivpu_pm_init(struct ivpu_device *vdev)
 	atomic_set(&pm->engine_reset_counter, 0);
 
 	INIT_WORK(&pm->recovery_work, ivpu_pm_recovery_work);
+	disable_work(&pm->recovery_work);
 	INIT_DELAYED_WORK(&pm->job_timeout_work, ivpu_job_timeout_work);
 
 	if (ivpu_disable_recovery)
@@ -439,6 +440,12 @@ void ivpu_pm_enable(struct ivpu_device *vdev)
 {
 	struct device *dev = vdev->drm.dev;
 
+	enable_work(&vdev->pm->recovery_work);
+	if (atomic_read(&vdev->pm->reset_pending)) {
+		queue_work(system_dfl_wq, &vdev->pm->recovery_work);
+		flush_work(&vdev->pm->recovery_work);
+	}
+
 	pm_runtime_allow(dev);
 	pm_runtime_put_autosuspend(dev);
 }

base-commit: 54d3ff1b5ac08d0e28029b93a1719ddd9ff670a4
-- 
2.43.0