Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail1.start.ca ([64.140.120.57]:46968 "EHLO mail1.start.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752300AbaDCQx6 (ORCPT ); Thu, 3 Apr 2014 12:53:58 -0400 Message-ID: <533D921E.4030001@pobox.com> Date: Thu, 03 Apr 2014 12:53:50 -0400 From: Mark Lord MIME-Version: 1.0 To: Albert Fluegel , "J. Bruce Fields" CC: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: linux-3.14 nfsd regression References: <533D8D73.1090603@pobox.com> <533D8FE9.80309@pobox.com> In-Reply-To: <533D8FE9.80309@pobox.com> Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: Mark Lord wrote: > On 14-04-03 12:33 PM, Mark Lord wrote: >> This commit from linux-3.14 breaks our NFS-root clients here: >> >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6e14b46b91fee8a049b0940333ce13a820beaaa5 >> >> >> - *p++ = htonl((u32) stat->mode); >> + *p++ = htonl((u32) (stat->mode & S_IALLUGO)); >> >> >> Reverting the one-liner above (on the server) fixes it for us, >> as does reverting back to linux-3.13.8 on the server. >> >> The NFS-root clients are on PowerPC (big-endian) architecture, >> running linux-3.12.16. The NFS server is on an Intel PC running linux-3.14. >> >> ACL is completely disabled on server and client, >> and we're using NFSv2/v3. No support for v4. >> >> I instrumented the function to see what other bits were being cleared >> by the (stat->mode & S_IALLUGO) masking. The results are attached. > .. > > > Looking into the (previously attached) trace, the bits that seem to be > getting chopped most often are S_IFREG (0x8000) and S_IFDIR (0x4000). > It appears that one/both of those are needed for mounting nfsroot. > > > [ 2733.823753] encode_fattr: mode=0x000041ed mask=0x00000fff > [ 2733.824217] encode_fattr: mode=0x000041ed mask=0x00000fff > [ 2733.838769] encode_fattr: mode=0x000041ed mask=0x00000fff > [ 2733.839175] encode_fattr: mode=0x0000a1ff mask=0x00000fff > [ 2733.839895] encode_fattr: mode=0x000081ed mask=0x00000fff ... Okay, the NFS root filesystem mounts and appears to work if I use this: *p++ = htonl((u32) (stat->mode & (S_IALLUGO | S_IFDIR | S_IFREG | S_IFCHR))); But I suspect it may also need S_IFBLK for block device accesses as well. Cheers