Re: [PATCH 5.10 000/406] 5.10.195-rc1 review

From: Greg Kroah-Hartman
Date: Wed Sep 20 2023 - 04:11:17 EST


On Tue, Sep 19, 2023 at 09:57:25PM -0700, Guenter Roeck wrote:
> On 9/17/23 12:07, Greg Kroah-Hartman wrote:
> > This is the start of the stable review cycle for the 5.10.195 release.
> > There are 406 patches in this series, all will be posted as a response
> > to this one. If anyone has any issues with these being applied, please
> > let me know.
> >
> > Responses should be made by Tue, 19 Sep 2023 19:10:04 +0000.
> > Anything received after that time might be too late.
> >
>
> chromeos-5.10 locks up in configfs_lookup() after the merge of v5.10.195.
>
> I am a bit puzzled because I see
>
> c709c7ca020a configfs: fix a race in configfs_lookup()
>
> in v5.10.195 but not in the list of commits below. I guess I must be
> missing something.

It was part of the big patchset, it was posted here:
https://lore.kernel.org/r/20230917191101.511939651@xxxxxxxxxxxxxxxxxxx

Not hidden at all :)

and was submitted here:
https://lore.kernel.org/r/ZPOZFHHA0abVmGx+@westworld

> Either case, the code now looks as follows.
>
> configfs_lookup()
> {
> ...
> spin_lock(&configfs_dirent_lock);
> ...
> err = configfs_attach_attr(sd, dentry);
> ...
> spin_unlock(&configfs_dirent_lock);
> ...
> }
>
> and
>
> configfs_attach_attr(...)
> {
> ...
> spin_lock(&configfs_dirent_lock);
> ...
> }
>
> which unless it is way too late here and I really need to go to sleep
> just won't work.

Kyle, you did the backport, any comments?

thanks,

greg k-h