linux-kernel - Re: [PATCH 1/2] watchdog: dw_wdt: pat the watchdog before enabling it

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: <20150127114403.71736c3f@xhacker>
Date:	Tue, 27 Jan 2015 11:44:03 +0800
From:	Jisheng Zhang <jszhang@...vell.com>
To:	Doug Anderson <dianders@...omium.org>
CC:	Guenter Roeck <linux@...ck-us.net>,
	Wim Van Sebroeck <wim@...ana.be>,
	Heiko Stuebner <heiko@...ech.de>,
	Lunxue Dai <lunxue.dai@...k-chips.com>,
	Dinh Nguyen <dinguyen@...era.com>,
	"linux-watchdog@...r.kernel.org" <linux-watchdog@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/2] watchdog: dw_wdt: pat the watchdog before enabling
 it

Dear Doug,

On Mon, 26 Jan 2015 09:01:37 -0800
Doug Anderson <dianders@...omium.org> wrote:

> Jisheng,
> 
> On Sun, Jan 25, 2015 at 10:22 PM, Jisheng Zhang <jszhang@...vell.com> wrote:
> >> Specifically I see the register WDT_TORR that has an offset of 0x4.
> >> That's the RANGE_REG in your code.  It shows bits 3:0 set the timeout
> >> period (0 = 0xffff and 15 = 0x7fffffff).  It shows bits 31:4 as
> >> "reserved".
> >
> > Could you please dump registers' value at offset 0xf4 and 0xf8 if you
> > don't mind?
> 
> Those are not documented in the user manual that I have, but:
> 
> >>> r(0xff8000f4)
> 0x10000a02
> >>> r(0xff8000f8)
> 0x3130332a

Thanks. Now I got some information about your platform:

wdt version: v1.02a

WDT_DUAL_TOP is configured as false, so there's no TOP_INIT
WDT_DFLT_TOP is configured as 0, so it will timeout soon.

However, it doesn't hurt anything if we have an extra pat before
enabling WDT

Thanks,
Jisheng
--
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/