[PATCH] dmaengine: idxd: fix RO device state error after been disabled/reset

[PATCH] dmaengine: idxd: fix RO device state error after been disabled/reset

[Fengqian Gao]

When IDXD is not configurable, that means its WQ, engine, and group
configurations cannot be changed. But it can be disabled and its state
should be set as disabled regardless it's configurable or not.

Fix this by setting device state IDXD_DEV_DISABLED for read-only device
as well in idxd_device_clear_state().

Fixes: cf4ac3fef338 ("dmaengine: idxd: fix lockdep warning on device driver removal")
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Xiaochen Shen <xiaochen.shen@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
---
 drivers/dma/idxd/device.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c
index 5a8cc52c1abf..bdd67728e507 100644
--- a/drivers/dma/idxd/device.c
+++ b/drivers/dma/idxd/device.c
@@ -724,13 +724,21 @@ static void idxd_device_wqs_clear_state(struct idxd_device *idxd)
 
 void idxd_device_clear_state(struct idxd_device *idxd)
 {
-	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
-		return;
+	/* IDXD is always disabled. Other states are cleared only when IDXD is configurable. */
+	if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags)) {
+		/*
+		 * Clearing wq state is protected by wq lock.
+		 * So no need to be protected by device lock.
+		 */
+		idxd_device_wqs_clear_state(idxd);
+
+		spin_lock(&idxd->dev_lock);
+		idxd_groups_clear_state(idxd);
+		idxd_engines_clear_state(idxd);
+	} else {
+		spin_lock(&idxd->dev_lock);
+	}
 
-	idxd_device_wqs_clear_state(idxd);
-	spin_lock(&idxd->dev_lock);
-	idxd_groups_clear_state(idxd);
-	idxd_engines_clear_state(idxd);
 	idxd->state = IDXD_DEV_DISABLED;
 	spin_unlock(&idxd->dev_lock);
 }
-- 
2.17.1

Re: [PATCH] dmaengine: idxd: fix RO device state error after been disabled/reset

[Vinod Koul]

On 30-09-22, 11:28, Fengqian Gao wrote:
> When IDXD is not configurable, that means its WQ, engine, and group
> configurations cannot be changed. But it can be disabled and its state
> should be set as disabled regardless it's configurable or not.
> 
> Fix this by setting device state IDXD_DEV_DISABLED for read-only device
> as well in idxd_device_clear_state().

Applied, thanks

-- 
~Vinod