[Potential Spoof] Re: kernel BUG at fs/jffs2/gc.c:395!

[Tao Ren]

On 8/26/19 9:42 PM, Tao Ren wrote:
> On 8/25/19 3:29 PM, Richard Weinberger wrote:
>> ----- Ursprüngliche Mail -----
>>> Von: "Tao Ren" <taoren at fb.com>
>>> An: "Richard Weinberger" <richard.weinberger at gmail.com>, "Andrew Jeffery" <andrew at aj.id.au>
>>> CC: "linux-mtd" <linux-mtd at lists.infradead.org>, "OpenBMC Maillist" <openbmc at lists.ozlabs.org>
>>> Gesendet: Montag, 26. August 2019 00:08:08
>>> Betreff: Re: kernel BUG at fs/jffs2/gc.c:395!
>>
>>> On 8/25/19 12:22 PM, Richard Weinberger wrote:
>>>> On Wed, Aug 21, 2019 at 2:06 AM Andrew Jeffery <andrew at aj.id.au> wrote:
>>>>> Looks like a lack of robustness to filesystem corruption to me. LWN
>>>>
>>>> What exactly makes you think so?
>>>> The inode cache entry is in state INO_STATE_UNCHECKED while GC run,
>>>> which is not allowed.
>>>>
>>>> Tao, is the error persistent or did it happen only once?
>>>
>>> Hi Richard,
>>>
>>> It rarely happens (~1 out of 1000 machines in my environment), but once it
>>> happens, it's persistent: the machine will fall into reboot loop due to the
>>> crash.
>>
>> Can you provide me an image of the filesystem such that I can have a look?
>> An image where the issue is persistent...
> 
> Hi Richard,
> 
> I tried kernel image with jffs2 summary enabled and disabled, and it looks to
> me the result is similar: I can reach login screen now, but the same kernel
> panic happens after "reboot" command.
> 
> The behavior is a little different from what I saw yesterday: previously kernel
> panic happened at boot time, and now it's after "reboot" command. I guess it's
> because more node being written to the flash?
> 
> I understand it's helpful to share the file system image, but unfortunately I
> cannot do it because it contains confidential data. Sorry about that..
> 
> Thank you again for the help, and kindly let me know if you have further
> suggestions.

Some interesting findings: I checked 3 impacted machines and all of them are
caused by the same set of files, and these files have been on the flash for
years without modification.


- Tao