linux-kernel - Re: [11/12] watchdog: sp5100-tco: Abort if watchdog is disabled by hardware

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, 9 Jan 2018 21:02:23 -0800
From:   Guenter Roeck <linux@...ck-us.net>
To:     Gabriel C <nix.or.die@...il.com>
Cc:     Lyude Paul <lyude@...hat.com>, Wim Van Sebroeck <wim@...ana.be>,
        linux-watchdog@...r.kernel.org,
        LKML <linux-kernel@...r.kernel.org>,
        Zoltán Böszörményi <zboszor@...hu>
Subject: Re: [11/12] watchdog: sp5100-tco: Abort if watchdog is disabled by
 hardware

On 01/09/2018 06:41 PM, Gabriel C wrote:
> 2018-01-10 3:09 GMT+01:00 Guenter Roeck <linux@...ck-us.net>:
>> On Wed, Jan 10, 2018 at 02:26:14AM +0100, Gabriel C wrote:
>>> On 10.01.2018 01:05, Guenter Roeck wrote:
>>>> Hi,
>>>>
>>>> On Wed, Jan 10, 2018 at 12:58:00AM +0100, Gabriel C wrote:
>>>>> On 10.01.2018 00:37, Guenter Roeck wrote:
>>>>>> Hi,
>>>>>>
>>>>>> On Tue, Jan 09, 2018 at 05:58:07PM -0500, Lyude Paul wrote:
>>>>>>> Hi! I'm the one from the Fedora bugzilla who said they'd help review these
>>>>>>> patches. I might end up responding to this with a real review comment after
>>>>>>> this message, but first:
>>>>>>>
>>>>>>> mind cc'ing me future versions of this patchset and also, is there any way you
>>>>>>
>>>>>> Sure.
>>>>>>
>>>>>>> know of that one could figure out whether or not the sp5100_tco wdt is
>>>>>>> actually disabled by the OEM on a board? I tried testing these patches with my
>>>>>>
>>>>>> That is what the code is trying to do today.
>>>>>>
>>>>>>> system and it appears to be convinced that it's disabled on my system, but I'm
>>>>>>> hoping something in this patch is just broken…
>>>>>>>
>>>>>>
>>>>>> I tested the driver on three different boards. MSI B350M MORTAR,
>>>>>> MSI B350 TOMAHAWK, and Gigabyte AB350M-Gaming 3. CPU is Ryzen 1700X
>>>>>> on all boards.
>>>>>>
>>>>>> On the MSI boards, the watchdog is reported as disabled. Enabling it
>>>>>> and letting it expire does not have an effect. I am using the Super-IO
>>>>>> watchdog instead on those boards (and it works).
>>>>>>
>>>>>> On the Gigabyte board, the watchdog is reported as enabled, and it works
>>>>>> (and the watchdog on the Super-IO chips does not work).
>>>>>>
>>>>>> Feel free to play with the driver. Maybe there is a means to enable the
>>>>>> watchdog if it is disabled. Unfortunately, I was unable to figure out how
>>>>>> to do it, so I thought it is better to report the fact and not instantiate
>>>>>> the watchdog if it doesn't work.
>>>>>>
>>>>>
>>>>> I haven an Supemricro H11DSi-NT with EPYCs CPUs..
>>>>> I can set the watchdog ON/OFF in BIOS and also set in to reset or NMI
>>>>> with the moatherboard jumpers.
>>>>>
>>>>> If you want I can give whatever patches for this driver an try ,
>>>>> just let me know.
>>>>>
>>>>
>>>> It would be great if you can test the series, even more so if you can test it
>>>> with the watchdog enabled and disabled . If you need to pull it from a git
>>>> repository, it is available from
>>>> git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git
>>>> in branch watchdog-next.
>>>>
>>>
>>> I've tested the branch ( on top latest linus/master ) with watchdog ON/OFF
>>> in BIOS and jumper set to reset ( default on this board )
>>>
>>> It seems no matter is enabled or disabled I always get a disabled message from the driver.
>>>
>>> [    4.246280] sp5100_tco: SP5100/SB800 TCO WatchDog Timer Driver
>>> [    4.247052] sp5100-tco sp5100-tco: Using 0xfed80b00 for watchdog MMIO address
>>> [    4.247181] sp5100-tco sp5100-tco: Watchdog hardware is disabled
>>>
>>> I got some strange NMI but this may not be related.
>>>
>>> 'Uhhuh. NMI received for unknown reason 3d on CPU 33' ( on all 64 CPUs )
>>>
>>>
>>> Maybe on that board is meant to 'enable' the BMC watchdog ..but BIOS tells
>>> 'if you enable watchdog the 5 minutes timer is started until OS/SW takes over'
>>>
>>> And a quick info shows there is no initial timer on the BMC Watchdog..
>>>
>>> crazy@ant:~/sp5100_tco$ sudo bmc-watchdog -g
>>> Timer Use:                   Reserved
>>> Timer:                       Stopped
>>> Logging:                     Enabled
>>> Timeout Action:              None
>>> Pre-Timeout Interrupt:       None
>>> Pre-Timeout Interval:        0 seconds
>>> Timer Use BIOS FRB2 Flag:    Clear
>>> Timer Use BIOS POST Flag:    Clear
>>> Timer Use BIOS OS Load Flag: Clear
>>> Timer Use BIOS SMS/OS Flag:  Clear
>>> Timer Use BIOS OEM Flag:     Clear
>>> Initial Countdown:           0 seconds
>>> Current Countdown:           0 seconds
>>>
>>>
>>> I try to have a closer look tomorrow.
>>>
>>
>> Can you run sensors-detect and provide the output ?
>> Maybe the board uses the watchdog from a Super-IO chip,
>> similar to the MSI boards.
>>
> 
> Only k10temp and IPMI BMC KCS is detected.
> Also the board seems to have 2 jumpers to enable/disable
> i2c SMB or something on SMB , which seems to be set to disabled by default.
> 

I can't comment on the i2c part, but other than that it looks like the IPMI BMC
is supposed to control everything.

Guenter