From: Guenter Roeck <linux@roeck-us.net>
To: Tomas Winkler <tomas.winkler@intel.com>
Cc: Wim Van Sebroeck <wim@iguana.be>,
linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org,
Alexander Usyskin <alexander.usyskin@intel.com>,
stable@vger.kernel.org
Subject: Re: [watchdog v2] watchdog: mei_wdt: request stop on unregister
Date: Sun, 24 Jan 2021 07:43:20 -0800 [thread overview]
Message-ID: <20210124154320.GA131753@roeck-us.net> (raw)
In-Reply-To: <20210124114938.373885-1-tomas.winkler@intel.com>
On Sun, Jan 24, 2021 at 01:49:38PM +0200, Tomas Winkler wrote:
> From: Alexander Usyskin <alexander.usyskin@intel.com>
>
> The MEI bus has a special behavior on suspend it destroys
> all the attached devices, this is due to the fact that also
> firmware context is not persistent across power flows.
>
> If watchdog on MEI bus is ticking before suspending the firmware
> times out and reports that the OS is missing watchdog tick.
> Send the stop command to the firmware on watchdog unregistered
> to eliminate the false event on suspend.
> This does not make the things worse from the user-space perspective
> as a user-space should re-open watchdog device after
> suspending before this patch.
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> ---
> V2: Update the commit message with better explanation
>
> drivers/watchdog/mei_wdt.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/watchdog/mei_wdt.c b/drivers/watchdog/mei_wdt.c
> index 5391bf3e6b11..c5967d8b4256 100644
> --- a/drivers/watchdog/mei_wdt.c
> +++ b/drivers/watchdog/mei_wdt.c
> @@ -382,6 +382,7 @@ static int mei_wdt_register(struct mei_wdt *wdt)
>
> watchdog_set_drvdata(&wdt->wdd, wdt);
> watchdog_stop_on_reboot(&wdt->wdd);
> + watchdog_stop_on_unregister(&wdt->wdd);
>
> ret = watchdog_register_device(&wdt->wdd);
> if (ret)
> --
> 2.26.2
>
prev parent reply other threads:[~2021-01-24 15:44 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-24 11:49 [watchdog v2] watchdog: mei_wdt: request stop on unregister Tomas Winkler
2021-01-24 15:43 ` Guenter Roeck [this message]
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=20210124154320.GA131753@roeck-us.net \
--to=linux@roeck-us.net \
--cc=alexander.usyskin@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-watchdog@vger.kernel.org \
--cc=stable@vger.kernel.org \
--cc=tomas.winkler@intel.com \
--cc=wim@iguana.be \
/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).