Re: 2.6.37-next - kernel BUG at fs/dcache.c:1363

From: Nick Piggin
Date: Thu Jan 06 2011 - 08:12:28 EST


On Thu, Jan 6, 2011 at 9:44 PM, Nick Piggin <npiggin@xxxxxxxxx> wrote:
> On Thu, Jan 6, 2011 at 4:15 AM,  <Valdis.Kletnieks@xxxxxx> wrote:
>> Saw this crash on a linux-next pulled yesterday at 2PM EST, kernel dies very
>> early (looks like first time it touches configfs for anything - trying to boot
>> with netconsole enabled caused it to die even faster).  I can bisect this if
>> it doesn't immediately ring a bell...
>
> Thanks, bah configfs isn't widely used.
>
>
>> It dies here:
>>
>> void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op)
>> {
>>        BUG_ON(dentry->d_op);
>>
>> Am guessing configfs passed in a dentry that wasn't filled in enough.
>>
>> (hand-transcribed from a crappy cellphone pic)
>>
>> kernel BUG at fs/dcache.c:1363
>
> Thanks. It actually passed in a dentry that appears to have already been
> used for something. This is not exactly a nice thing for a filesystem to do
> and probably indicates an underlying bug anyway (or at least something
> the vfs doesn't guarantee the safety of).
>
> Taking a look now.

This patch fixes it here

Attachment: dentry-debug.patch
Description: Binary data