> On Nov 23, 2022, at 12:50 PM, Anders Blomdell <anders.blomdell@xxxxxxxxxxxxxx> 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 <anders.blomdell@xxxxxxxxxxxxxx> > Link: https://bugzilla.redhat.com/show_bug.cgi?id=2142132 > Fixes: bfbfb6182ad1 "nfsd_splice_actor(): handle compound pages" > Cc: stable@xxxxxxxxxxxxxxx # 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
