From: Nicolas Dufresne <nicolas.dufresne@collabora.com>
To: linux-media@vger.kernel.org, Maxime Ripard <mripard@kernel.org>,
Paul Kocialkowski <paul.kocialkowski@bootlin.com>,
Mauro Carvalho Chehab <mchehab@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Chen-Yu Tsai <wens@csie.org>,
Jernej Skrabec <jernej.skrabec@gmail.com>,
Samuel Holland <samuel@sholland.org>
Cc: kernel@collabora.com,
Dmitry Osipenko <dmitry.osipenko@collabora.com>,
stable@vger.kernel.org,
Nicolas Dufresne <nicolas.dufresne@collabora.com>,
linux-staging@lists.linux.dev,
linux-arm-kernel@lists.infradead.org,
linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: [PATCH v1 3/3] media: cedrus: Fix endless loop in cedrus_h265_skip_bits()
Date: Thu, 18 Aug 2022 16:33:08 -0400 [thread overview]
Message-ID: <20220818203308.439043-4-nicolas.dufresne@collabora.com> (raw)
In-Reply-To: <20220818203308.439043-1-nicolas.dufresne@collabora.com>
From: Dmitry Osipenko <dmitry.osipenko@collabora.com>
The busy status bit may never de-assert if number of programmed skip
bits is incorrect, resulting in a kernel hang because the bit is polled
endlessly in the code. Fix it by adding timeout for the bit-polling.
This problem is reproducible by setting the data_bit_offset field of
the HEVC slice params to a wrong value by userspace.
Cc: stable@vger.kernel.org
Reported-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
---
drivers/staging/media/sunxi/cedrus/cedrus_h265.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c
index f703c585d91c5..f0bc118021b0a 100644
--- a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c
@@ -227,6 +227,7 @@ static void cedrus_h265_pred_weight_write(struct cedrus_dev *dev,
static void cedrus_h265_skip_bits(struct cedrus_dev *dev, int num)
{
int count = 0;
+ u32 reg;
while (count < num) {
int tmp = min(num - count, 32);
@@ -234,8 +235,9 @@ static void cedrus_h265_skip_bits(struct cedrus_dev *dev, int num)
cedrus_write(dev, VE_DEC_H265_TRIGGER,
VE_DEC_H265_TRIGGER_FLUSH_BITS |
VE_DEC_H265_TRIGGER_TYPE_N_BITS(tmp));
- while (cedrus_read(dev, VE_DEC_H265_STATUS) & VE_DEC_H265_STATUS_VLD_BUSY)
- udelay(1);
+
+ if (cedrus_wait_for(dev, VE_DEC_H265_STATUS, VE_DEC_H265_STATUS_VLD_BUSY))
+ dev_err_ratelimited(dev->dev, "timed out waiting to skip bits\n");
count += tmp;
}
--
2.37.2
next prev parent reply other threads:[~2022-08-18 20:34 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20220818203308.439043-1-nicolas.dufresne@collabora.com>
2022-08-18 20:33 ` [PATCH v1 1/3] media: cedrus: Fix watchdog race condition Nicolas Dufresne
2022-08-22 8:04 ` Paul Kocialkowski
2022-08-25 21:02 ` Jernej Škrabec
2022-08-18 20:33 ` [PATCH v1 2/3] media: cedrus: Set the platform driver data earlier Nicolas Dufresne
2022-08-19 4:17 ` Jernej Škrabec
2022-08-19 15:37 ` Nicolas Dufresne
2022-08-20 8:25 ` Jernej Škrabec
2022-08-21 20:40 ` Dmitry Osipenko
2022-08-25 21:04 ` Jernej Škrabec
2022-08-23 3:57 ` Samuel Holland
2022-08-23 12:22 ` Paul Kocialkowski
2022-08-18 20:33 ` Nicolas Dufresne [this message]
2022-08-18 20:39 ` [PATCH v1 3/3] media: cedrus: Fix endless loop in cedrus_h265_skip_bits() Dmitry Osipenko
2022-08-18 21:17 ` Nicolas Dufresne
2022-08-19 4:16 ` Jernej Škrabec
2022-08-19 15:39 ` Nicolas Dufresne
2022-08-25 21:13 ` Jernej Škrabec
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=20220818203308.439043-4-nicolas.dufresne@collabora.com \
--to=nicolas.dufresne@collabora.com \
--cc=dmitry.osipenko@collabora.com \
--cc=gregkh@linuxfoundation.org \
--cc=jernej.skrabec@gmail.com \
--cc=kernel@collabora.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-staging@lists.linux.dev \
--cc=linux-sunxi@lists.linux.dev \
--cc=mchehab@kernel.org \
--cc=mripard@kernel.org \
--cc=paul.kocialkowski@bootlin.com \
--cc=samuel@sholland.org \
--cc=stable@vger.kernel.org \
--cc=wens@csie.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;
as well as URLs for NNTP newsgroup(s).