From: Jarkko Nikula <jarkko.nikula@linux.intel.com>
To: Tam Nguyen <tamnguyenchi@os.amperecomputing.com>,
linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org
Cc: patches@amperecomputing.com, andriy.shevchenko@linux.intel.com,
mika.westerberg@linux.intel.com, jsd@semihalf.com,
chuong@os.amperecomputing.com, darren@os.amperecomputing.com,
stable@vger.kernel.org
Subject: Re: [PATCH v2 2/2] i2c: designware: Handle invalid SMBus block data response length value
Date: Thu, 27 Jul 2023 13:49:36 +0300 [thread overview]
Message-ID: <d1ec82a2-5c16-c3dd-147f-1e5256acffcd@linux.intel.com> (raw)
In-Reply-To: <20230726080001.337353-3-tamnguyenchi@os.amperecomputing.com>
On 7/26/23 11:00, Tam Nguyen wrote:
> In the I2C_FUNC_SMBUS_BLOCK_DATA case, the invalid length byte value
> (outside of 1-32) of the SMBus block data response from the Slave device
> is not correctly handled by the I2C Designware driver.
>
> In case IC_EMPTYFIFO_HOLD_MASTER_EN==1, which cannot be detected
> from the registers, the Master can be disabled only if the STOP bit
> is set. Without STOP bit set, the Master remains active, holding the bus
> until receiving a block data response length. This hangs the bus and
> is unrecoverable.
>
> Avoid this by issuing another dump read to reach the stop condition when
> an invalid length byte is received.
>
> Cc: stable@vger.kernel.org
> Signed-off-by: Tam Nguyen <tamnguyenchi@os.amperecomputing.com>
> ---
> drivers/i2c/busses/i2c-designware-master.c | 15 +++++++++++++--
> 1 file changed, 13 insertions(+), 2 deletions(-)
>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
next prev parent reply other threads:[~2023-07-27 10:49 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20230726080001.337353-1-tamnguyenchi@os.amperecomputing.com>
2023-07-26 8:00 ` [PATCH v2 1/2] i2c: designware: Correct length byte validation logic Tam Nguyen
2023-07-27 10:36 ` Jarkko Nikula
2023-08-14 13:29 ` Wolfram Sang
2023-07-26 8:00 ` [PATCH v2 2/2] i2c: designware: Handle invalid SMBus block data response length value Tam Nguyen
2023-07-27 10:49 ` Jarkko Nikula [this message]
2023-08-14 13:29 ` Wolfram Sang
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=d1ec82a2-5c16-c3dd-147f-1e5256acffcd@linux.intel.com \
--to=jarkko.nikula@linux.intel.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=chuong@os.amperecomputing.com \
--cc=darren@os.amperecomputing.com \
--cc=jsd@semihalf.com \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mika.westerberg@linux.intel.com \
--cc=patches@amperecomputing.com \
--cc=stable@vger.kernel.org \
--cc=tamnguyenchi@os.amperecomputing.com \
/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