mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Jia-Ju Bai <baijiaju1990@gmail.com>
To: fabien.dessenne@st.com, mchehab@kernel.org
Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
	Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [PATCH 1/2] bdisp: Fix a possible sleep-in-atomic bug in bdisp_hw_reset
Date: Tue, 12 Dec 2017 21:47:25 +0800	[thread overview]
Message-ID: <1513086445-29265-1-git-send-email-baijiaju1990@gmail.com> (raw)

The driver may sleep under a spinlock.
The function call path is:
bdisp_device_run (acquire the spinlock)
  bdisp_hw_reset
    msleep --> may sleep

To fix it, msleep is replaced with mdelay.

This bug is found by my static analysis tool(DSAC) and checked by my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
 drivers/media/platform/sti/bdisp/bdisp-hw.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/sti/bdisp/bdisp-hw.c b/drivers/media/platform/sti/bdisp/bdisp-hw.c
index b7892f3..4b62ceb 100644
--- a/drivers/media/platform/sti/bdisp/bdisp-hw.c
+++ b/drivers/media/platform/sti/bdisp/bdisp-hw.c
@@ -382,7 +382,7 @@ int bdisp_hw_reset(struct bdisp_dev *bdisp)
 	for (i = 0; i < POLL_RST_MAX; i++) {
 		if (readl(bdisp->regs + BLT_STA1) & BLT_STA1_IDLE)
 			break;
-		msleep(POLL_RST_DELAY_MS);
+		mdelay(POLL_RST_DELAY_MS);
 	}
 	if (i == POLL_RST_MAX)
 		dev_err(bdisp->dev, "Reset timeout\n");
-- 
1.7.9.5

             reply	other threads:[~2017-12-12 13:45 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-12 13:47 Jia-Ju Bai [this message]
2017-12-15 14:16 ` Hans Verkuil
2017-12-15 14:51 ` Fabien DESSENNE
2017-12-16 11:53   ` Jia-Ju Bai
2017-12-16 14:14     ` Mauro Carvalho Chehab
2017-12-19  9:01       ` Fabien DESSENNE
2017-12-19  9:40         ` Mauro Carvalho Chehab

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1513086445-29265-1-git-send-email-baijiaju1990@gmail.com \
    --to=baijiaju1990@gmail.com \
    --cc=fabien.dessenne@st.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=mchehab@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®