Date: Sun, 18 Jun 2017 22:45:35 +0800 From: Jia-Ju Bai <baijiaju1990@163.com> To: njm@njm.me.uk, freebsd-drivers@freebsd.org, freebsd-bugs@freebsd.org, freebsd-scsi@freebsd.org Cc: Jia-Ju Bai <baijiaju1990@163.com> Subject: [PATCH] dpt_scsi: Fix a possible sleep-under-mutex bug in dpt_init (different from Bug 220095) Message-ID: <20170618144535.41858-1-baijiaju1990@163.com>
next in thread | raw e-mail | index | archive | help
The driver may sleep under a mutex, and the code path is:
dpt_init [line 1134: acquire the mutex]
bus_dma_tag_create(BUS_DMA_WAITOK) [line 1143] --> may sleep
The possible fix of this bug is to replace "BUS_DMA_WAITOK" in bus_dma_tag_create with "BUS_DMA_NOWAIT".
This bug is found by a static analysis tool written by myself, and it is
checked by my review of the FreeBSD code.
Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
---
sys/dev/dpt/dpt_scsi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sys/dev/dpt/dpt_scsi.c b/sys/dev/dpt/dpt_scsi.c
index 541b58665cf..d69a443067a 100644
--- a/sys/dev/dpt/dpt_scsi.c
+++ b/sys/dev/dpt/dpt_scsi.c
@@ -1150,7 +1150,7 @@ dpt_init(struct dpt_softc *dpt)
/* maxsize */ PAGE_SIZE,
/* nsegments */ 1,
/* maxsegsz */ BUS_SPACE_MAXSIZE_32BIT,
- /* flags */ 0,
+ /* flags */ BUS_DMA_NOWAIT,
/* lockfunc */ NULL,
/* lockarg */ NULL,
&dpt->sg_dmat) != 0) {
--
2.13.0
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20170618144535.41858-1-baijiaju1990>