On Mon, 27 Mar 2023 11:19:01 +0800 Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx> wrote:
>
>
> 在 2023/3/25 3:42, Andrew Morton 写道:
> > On Fri, 24 Mar 2023 10:28:00 +0000 Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx> wrote:
> >
> >> XFS allows CoW on non-shared extents to combat fragmentation[1]. The
> >> old non-shared extent could be mwrited before, its dax entry is marked
> >> dirty. To be able to delete this entry, clear its dirty mark before
> >> invalidate_inode_pages2_range().
> >
> > What are the user-visible runtime effects of this flaw?
>
> This bug won't leak or mess up the data of filesystem. In dmesg it will
> show like this:
>
> [ 28.512349] ------------[ cut here ]------------
> [ 28.512622] WARNING: CPU: 2 PID: 5255 at fs/dax.c:390
> dax_insert_entry+0x342/0x390
>
> ...
>
> >
> > Are we able to identify a Fixes: target for this? Perhaps
> > f80e1668888f3 ("fsdax: invalidate pages when CoW")?
> >
>
> Yes, it is to fix this commit.
OK, thanks. I added the extra changelog info, added the Fixes and a
cc:stable.
Some review from other fsdax developers would be helpful, please.
