From: Jerry Snitselaar <jsnitsel@redhat.com>
Date: Tue, 23 Aug 2022 16:37:09 +0000 (-0700)
Subject: dmaengine: idxd: avoid deadlock in process_misc_interrupts()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=407171717a4f4d2d80825584643374a2dfdb0540;p=linux.git

dmaengine: idxd: avoid deadlock in process_misc_interrupts()

idxd_device_clear_state() now grabs the idxd->dev_lock
itself, so don't grab the lock prior to calling it.

This was seen in testing after dmar fault occurred on system,
resulting in lockup stack traces.

Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org
Fixes: cf4ac3fef338 ("dmaengine: idxd: fix lockdep warning on device driver removal")
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20220823163709.2102468-1-jsnitsel@redhat.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
---

diff --git a/drivers/dma/idxd/irq.c b/drivers/dma/idxd/irq.c
index 743ead5ebc579..5b9921475be6c 100644
--- a/drivers/dma/idxd/irq.c
+++ b/drivers/dma/idxd/irq.c
@@ -324,13 +324,11 @@ halt:
 			idxd->state = IDXD_DEV_HALTED;
 			idxd_wqs_quiesce(idxd);
 			idxd_wqs_unmap_portal(idxd);
-			spin_lock(&idxd->dev_lock);
 			idxd_device_clear_state(idxd);
 			dev_err(&idxd->pdev->dev,
 				"idxd halted, need %s.\n",
 				gensts.reset_type == IDXD_DEVICE_RESET_FLR ?
 				"FLR" : "system reset");
-			spin_unlock(&idxd->dev_lock);
 			return -ENXIO;
 		}
 	}