linux-kernel - Re: [PATCH v3] cifs: Silently ignore unknown oplock break handle

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Date:   Thu, 25 Mar 2021 10:21:15 -0500
From:   Steve French <smfrench@...il.com>
To:     Tom Talpey <tom@...pey.com>
Cc:     Vincent Whitchurch <vincent.whitchurch@...s.com>,
        Steve French <sfrench@...ba.org>,
        CIFS <linux-cifs@...r.kernel.org>, kernel <kernel@...s.com>,
        samba-technical <samba-technical@...ts.samba.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v3] cifs: Silently ignore unknown oplock break handle

merged into cifs-2.6.git for-next

On Fri, Mar 19, 2021 at 9:06 AM Tom Talpey via samba-technical
<samba-technical@...ts.samba.org> wrote:
>
> LGTM feel free to add
>
> Reviewed-By: Tom Talpey <tom@...pey.com>
>
> On 3/19/2021 9:57 AM, Vincent Whitchurch wrote:
> > Make SMB2 not print out an error when an oplock break is received for an
> > unknown handle, similar to SMB1.  The debug message which is printed for
> > these unknown handles may also be misleading, so fix that too.
> >
> > The SMB2 lease break path is not affected by this patch.
> >
> > Without this, a program which writes to a file from one thread, and
> > opens, reads, and writes the same file from another thread triggers the
> > below errors several times a minute when run against a Samba server
> > configured with "smb2 leases = no".
> >
> >   CIFS: VFS: \\192.168.0.1 No task to wake, unknown frame received! NumMids 2
> >   00000000: 424d53fe 00000040 00000000 00000012  .SMB@...........
> >   00000010: 00000001 00000000 ffffffff ffffffff  ................
> >   00000020: 00000000 00000000 00000000 00000000  ................
> >   00000030: 00000000 00000000 00000000 00000000  ................
> >
> > Signed-off-by: Vincent Whitchurch <vincent.whitchurch@...s.com>
> > ---
> >
> > Notes:
> >      v3:
> >      - Change debug print to Tom Talpey's suggestion
> >
> >      v2:
> >      - Drop change to lease break
> >      - Rewrite commit message
> >
> >   fs/cifs/smb2misc.c | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
> > index 60d4bd1eae2b..76cd05b8d53b 100644
> > --- a/fs/cifs/smb2misc.c
> > +++ b/fs/cifs/smb2misc.c
> > @@ -754,8 +754,8 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
> >               }
> >       }
> >       spin_unlock(&cifs_tcp_ses_lock);
> > -     cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
> > -     return false;
> > +     cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
> > +     return true;
> >   }
> >
> >   void
> >
>


-- 
Thanks,

Steve