Re: uninterruptible I/O wait on CIFS mounts on Amazon Linux 2 running latest kernel

[Pavel Shilovsky <piastryyy@gmail.com>]

There are only two changes between v4.14.114 and v4.4.121:

----------------------------------------
$ git diff v4.14.114 v4.14.121 -- fs/cifs
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 6fd4a6a75234..e7192ee7a89c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1730,6 +1730,10 @@ cifs_do_rename(const unsigned int xid, struct
dentry *from_dentry,
        if (rc == 0 || rc != -EBUSY)
                goto do_rename_exit;

+       /* Don't fall back to using SMB on SMB 2+ mount */
+       if (server->vals->protocol_id != 0)
+               goto do_rename_exit;
+
        /* open-file renames don't work across directories */
        if (to_dentry->d_parent != from_dentry->d_parent)
                goto do_rename_exit;
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index fd2d199dd413..7936eac5a38a 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2699,6 +2699,7 @@ SMB2_read(const unsigned int xid, struct
cifs_io_parms *io_parms,
                        cifs_dbg(VFS, "Send error in read = %d\n", rc);
                }
                free_rsp_buf(resp_buftype, rsp_iov.iov_base);
+               cifs_small_buf_release(req);
                return rc == -ENODATA ? 0 : rc;
        }

----------------------------------------

Both fixes seem to be legitimate and shouldn't cause the issue
directly. Please provide the logs (as mentioned by Aurelien above)
together with mount command options. If you have a small simple repro
setup/script/program that would help too.

--
Best regards,
Pavel Shilovsky

пт, 14 июн. 2019 г. в 06:23, Aurélien Aptel <aaptel@suse.com>:
>
> Hi Ben,
>
> Any chance we can get a verbose kernel log and network trace?
> See https://wiki.samba.org/index.php/Bug_Reporting#cifs.ko
> for instructions.
>
> --
> Aurélien Aptel / SUSE Labs Samba Team
> GPG: 1839 CB5F 9F5B FB9B AA97  8C99 03C8 A49B 521B D5D3
> SUSE Linux GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
> GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 21284 (AG Nürnberg)