Re: dcache_readdir NULL inode oops

From: Will Deacon
Date: Fri Nov 09 2018 - 10:59:00 EST


On Fri, Nov 09, 2018 at 02:37:51PM +0000, Jan Glauber wrote:
> I'm seeing the following oops reproducible with upstream kernel on arm64
> (ThunderX2):

[...]

> It happens after 1-3 hours of running 'stress-ng --dev 128'. This testcase
> does a scandir of /dev and then calls random stuff like ioctl, lseek,
> open/close etc. on the entries. I assume no files are deleted under /dev
> during the testcase.
>
> The NULL pointer is the inode pointer of next. The next dentry->d_flags is
> DCACHE_RCUACCESS when this happens.
>
> Any hints on how to further debug this?

Can you reproduce the issue with vanilla -rc1 and do you have a "known good"
kernel?

Will