From: Dave Jiang dave.jiang@intel.com
stable inclusion from stable-5.10.69 commit 48271d10bf4cbdd4693ad4f94fb14c2aa7fcc4c5 bugzilla: 182675 https://gitee.com/openeuler/kernel/issues/I4I3ED
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 673d812d30be67942762bb9e8548abb26a3ba4a7 ]
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@djia... Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- 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 417048e3c42a..0368c5490788 100644 --- a/drivers/dma/idxd/submit.c +++ b/drivers/dma/idxd/submit.c @@ -45,7 +45,7 @@ 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(); }