linux-kernel - Re: [PATCH v4 1/2] watchdog: New watchdog driver for MEN A21 watchdogs

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]

Message-ID: <20130530215203.GJ14258@spo001.leaseweb.com>
Date:	Thu, 30 May 2013 23:52:03 +0200
From:	Wim Van Sebroeck <wim@...ana.be>
To:	Johannes Thumshirn <johannes.thumshirn@....de>
Cc:	linux-watchdog@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 1/2] watchdog: New watchdog driver for MEN A21 watchdogs

Hi Johannes,

> On Mon, May 27, 2013 at 08:25:54PM +0200, Wim Van Sebroeck wrote:
> [...]
> > > +	watchdog_set_drvdata(&a21_wdt, drv);
> >
> > I am missing the initialisation of the watchdog's timeout value here...
> 
> This watchdog only knows two timeout values, 1s and 30s with the constraint
> that you can't go back to 30s once your in a 1s timeout without a reset of the
> CPLD. I could initially set it to 30s but that would be redundant.

Yes, but if I use a WDIOC_GETTIMEOUT ioctl call then I will get 0 because
you didn't initialize a21_wdt.timeout so you don't know wether or not
it's 30 or 1.

You can also set it default to 1 and use a timer to do the bridge between userspace
and an in kernel timer of 0.5msec. (see git/linux-watchdog/drivers/watchdog/pika_wdt.c
as an example).

Kind regards,
Wim.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/