From 673d812d30be67942762bb9e8548abb26a3ba4a7 Mon Sep 17 00:00:00 2001
From: Dave Jiang <dave.jiang@intel.com>
Date: Thu, 22 Jul 2021 10:54:10 -0700
Subject: [PATCH] dmaengine: idxd: fix wq slot allocation index check
Git-commit: 673d812d30be67942762bb9e8548abb26a3ba4a7
Patch-mainline: v5.15-rc1
References: git-fixes stable-5.14.8
The sbitmap wait and allocate routine checks the index that is returned
from sbitmap_queue_get(). It should be idxd >= 0 as 0 is also a valid
index. This fixes issue where submission path hangs when WQ size is 1.
Fixes: 0705107fcc80 ("dmaengine: idxd: move submission to sbitmap_queue")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162697645067.3478714.506720687816951762.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/dma/idxd/submit.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/dma/idxd/submit.c b/drivers/dma/idxd/submit.c
index 6ef704dd4d0b..65b0130ab2db 100644
--- a/drivers/dma/idxd/submit.c
+++ b/drivers/dma/idxd/submit.c
@@ -59,7 +59,7 @@ struct idxd_desc *idxd_alloc_desc(struct idxd_wq *wq, enum idxd_op_type optype)
if (signal_pending_state(TASK_INTERRUPTIBLE, current))
break;
idx = sbitmap_queue_get(sbq, &cpu);
- if (idx > 0)
+ if (idx >= 0)
break;
schedule();
}
--
2.26.2