> On Nov 23, 2022, at 12:50 PM, Anders Blomdell <[email protected]> wrote:
>
> Make nfsd_splice_actor work with reads with a non-zero offset that doesn't end on a page boundary.
>
> This was found when virtual machines with nfs-mounted qcow2 disks failed to boot properly (originally found
> on v6.0.5, fix also needed and tested on v6.0.9 and v6.1-rc6).
>
> Signed-off-by: Anders Blomdell <[email protected]>
> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2142132
> Fixes: bfbfb6182ad1 "nfsd_splice_actor(): handle compound pages"
> Cc: [email protected] # v6.0+
>
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -873,7 +873,7 @@ nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
> unsigned offset = buf->offset;
> page += offset / PAGE_SIZE;
> - for (int i = sd->len; i > 0; i -= PAGE_SIZE)
> + for (int i = sd->len + offset % PAGE_SIZE; i > 0; i -= PAGE_SIZE)
> svc_rqst_replace_page(rqstp, page++);
> if (rqstp->rq_res.page_len == 0) // first call
> rqstp->rq_res.page_base = offset % PAGE_SIZE;
Thanks. I actually find Al's suggestion (posted in the other thread)
preferable. Can you test that and repost? I will then apply the fix
immediately to nfsd's for-rc tree.
--
Chuck Lever