linux-kernel - Re: [PATCH v2 2/2] i2c: at91: manage unexpected RXRDY flag when starting a transfer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 22 Oct 2015 15:08:47 +0200
From:	Wolfram Sang <wsa@...-dreams.de>
To:	Ludovic Desroches <ludovic.desroches@...el.com>
Cc:	linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, nicolas.ferre@...el.com,
	peda@...ator.liu.se, cyrille.pitchen@...el.com
Subject: Re: [PATCH v2 2/2] i2c: at91: manage unexpected RXRDY flag when
 starting a transfer

On Wed, Oct 21, 2015 at 03:44:04PM +0200, Ludovic Desroches wrote:
> In some cases, we could start a new i2c transfer with the RXRDY flag
> set. It is not a clean state and it leads to print annoying error
> messages even if there no real issue. The cause is only having garbage
> data in the Receive Holding Register because of a weird behavior of the
> RXRDY flag.
> 
> Signed-off-by: Ludovic Desroches <ludovic.desroches@...el.com>
> Fixes: 93563a6a71bb ("i2c: at91: fix a race condition when using the DMA
> controller")
> Reported-by: Peter Rosin <peda@...ator.liu.se>
> Tested-by: Peter Rosin <peda@...ator.liu.se>
> Cc: stable@...r.kernel.org #4.1

    SMATCH
drivers/i2c/busses/i2c-at91.c:602 at91_do_twi_transfer warn: unused return: sr = at91_twi_read()

drivers/i2c/busses/i2c-at91.c: In function 'at91_do_twi_transfer':
drivers/i2c/busses/i2c-at91.c:550:11: warning: variable 'sr' set but not used [-Wunused-but-set-variable]
  unsigned sr;
           ^

Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)