Commit cf4ac3fe authored by Dave Jiang's avatar Dave Jiang Committed by Vinod Koul
Browse files

dmaengine: idxd: fix lockdep warning on device driver removal 



Jacob reported that with lockdep debug turned on, idxd_device_driver
removal causes kernel splat from lock assert warning for
idxd_device_wqs_clear_state(). Make sure
idxd_device_wqs_clear_state() holds the wq lock for each wq when
cleaning the wq state. Move the call outside of the device spinlock.

Reported-by: default avatarJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/165231364426.986304.9294302800482492780.stgit@djiang5-desk3.ch.intel.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 42a1b738

drivers/dma/idxd/device.c

+7 −7
Original line number Diff line number Diff line
@@ -578,19 +578,15 @@ int idxd_device_disable(struct idxd_device *idxd) 
		return -ENXIO;

	}



	spin_lock(&idxd->dev_lock);

	idxd_device_clear_state(idxd);

	idxd->state = IDXD_DEV_DISABLED;

	spin_unlock(&idxd->dev_lock);

	return 0;

}



void idxd_device_reset(struct idxd_device *idxd)

{

	idxd_cmd_exec(idxd, IDXD_CMD_RESET_DEVICE, 0, NULL);

	spin_lock(&idxd->dev_lock);

	idxd_device_clear_state(idxd);

	idxd->state = IDXD_DEV_DISABLED;

	spin_lock(&idxd->dev_lock);

	idxd_unmask_error_interrupts(idxd);

	spin_unlock(&idxd->dev_lock);

}
@@ -717,23 +713,27 @@ static void idxd_device_wqs_clear_state(struct idxd_device *idxd) 
{

	int i;



	lockdep_assert_held(&idxd->dev_lock);

	for (i = 0; i < idxd->max_wqs; i++) {

		struct idxd_wq *wq = idxd->wqs[i];



		if (wq->state == IDXD_WQ_ENABLED) {

			mutex_lock(&wq->wq_lock);

			idxd_wq_disable_cleanup(wq);

			idxd_wq_device_reset_cleanup(wq);

			wq->state = IDXD_WQ_DISABLED;

			mutex_unlock(&wq->wq_lock);

		}

	}

}



void idxd_device_clear_state(struct idxd_device *idxd)

{

	idxd_device_wqs_clear_state(idxd);

	spin_lock(&idxd->dev_lock);

	idxd_groups_clear_state(idxd);

	idxd_engines_clear_state(idxd);

	idxd_device_wqs_clear_state(idxd);

	idxd->state = IDXD_DEV_DISABLED;

	spin_unlock(&idxd->dev_lock);

}



static void idxd_group_config_write(struct idxd_group *group)