Re: ext4: fix reference counting bug on block allocation error

Vegard Nossum
2016-08-14T18:38:37Z

On 08/14/2016 08:32 PM, Greg KH wrote:
> Hi Vegard and ext4 developers,
>
> The patch below, in Linus's tree, references a patch in the Fixes: line
> that is not in Linus's tree (neither the git commit id, nor the subject
> line.)
>

It seems to exist?

>> Fixes: 8556e8f3b6 ("ext4: Don't allow new groups to be added during
block allocation")

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8556e8f3b6c4c11601ce1e9ea8090a6d8bd5daae

> That's a bit confusing, what is this patch supposed to be fixing up?
> What stable tree(s) should it go to if the original patch it fixes isn't
> even in any tree?

The referenced commit adds the ext4_mb_release_context(ac); line which
is what is causing problems because that releases the context which is
still in fact in use.

>
> confused,

Confused too :-)

Vegard