linux-kernel - Re: [PATCH v2 1/1] watchdog: sp805: ping fails to abort wdt reset

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:	Tue, 19 Jan 2016 14:48:24 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	Sandeep Tripathy <tripathy@...adcom.com>
Cc:	wim@...ana.be, linux-watchdog@...r.kernel.org,
	linux-kernel@...r.kernel.org, bcm-kernel-feedback-list@...adcom.com
Subject: Re: [PATCH v2 1/1] watchdog: sp805: ping fails to abort wdt reset

On 19-01-16, 14:44, Sandeep Tripathy wrote:
> sp805 wdt asserts interrupt for the first expiry and
> reloads the counter. If wdt interrupt is set and count
> reaches zero then wdt reset event is generated. To get
> wdt reset at 't' timeout the driver loads wdt counter
> with 't/2'. A ping before time 't'  *should* prevent
> wdt reset. Currently if ping is done after 't/2' then
> wdt interrupt condition gets set. On the next countdown
> of loadval wdt reset event occurs eventhough wdt was
> reloaded before the set timeout 't'.
> 
> This patch clears the interrupt condition on ping.
> 
> Signed-off-by: Sandeep Tripathy <tripathy@...adcom.com>
> ---
>  drivers/watchdog/sp805_wdt.c |    5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> index 01d8162..e7a715e 100644
> --- a/drivers/watchdog/sp805_wdt.c
> +++ b/drivers/watchdog/sp805_wdt.c
> @@ -139,12 +139,11 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
>  
>  	writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
>  	writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> +	writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
>  
> -	if (!ping) {
> -		writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> +	if (!ping)
>  		writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
>  				WDTCONTROL);
> -	}
>  
>  	writel_relaxed(LOCK, wdt->base + WDTLOCK);

Acked-by: Viresh Kumar <viresh.kumar@...aro.org>

-- 
viresh