[PATCH AUTOSEL for 4.9 051/293] scsi: megaraid: Fix a sleep-in-atomic bug

From: Sasha Levin
Date: Sun Apr 08 2018 - 22:35:41 EST


From: Jia-Ju Bai <baijiaju1990@xxxxxxx>

[ Upstream commit 896f6966fc815abe71f85fb26f0193875df8a035 ]

The driver may sleep under a spin lock, and the function call path is:
mraid_mm_attach_buf (acquire the lock by spin_lock_irqsave)
pci_pool_alloc(GFP_KERNEL) --> may sleep

To fix it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC".

[mkp: fixed whitespace]

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxx>
Acked-by: Sumit Saxena <sumit.saxena@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/scsi/megaraid/megaraid_mm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/megaraid/megaraid_mm.c b/drivers/scsi/megaraid/megaraid_mm.c
index 4cf9ed96414f..544d6f7e6138 100644
--- a/drivers/scsi/megaraid/megaraid_mm.c
+++ b/drivers/scsi/megaraid/megaraid_mm.c
@@ -574,7 +574,7 @@ mraid_mm_attach_buf(mraid_mmadp_t *adp, uioc_t *kioc, int xferlen)

kioc->pool_index = right_pool;
kioc->free_buf = 1;
- kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_KERNEL,
+ kioc->buf_vaddr = pci_pool_alloc(pool->handle, GFP_ATOMIC,
&kioc->buf_paddr);
spin_unlock_irqrestore(&pool->lock, flags);

--
2.15.1