On Thu, Feb 02, 2023 at 04:55:03PM -0800, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> When writing a page from an encrypted file that is using
> filesystem-layer encryption (not inline encryption), ext4 encrypts the
> pagecache page into a bounce page, then writes the bounce page.
>
> It also passes the bounce page to wbc_account_cgroup_owner(). That's
> incorrect, because the bounce page is a newly allocated temporary page
> that doesn't have the memory cgroup of the original pagecache page.
> This makes wbc_account_cgroup_owner() not account the I/O to the owner
> of the pagecache page as it should.
>
> Fix this by always passing the pagecache page to
> wbc_account_cgroup_owner().
>
> Fixes: 001e4a8775f6 ("ext4: implement cgroup writeback support")
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Thanks.
--
tejun
