On Tue, Nov 13, 2007 at 11:04:00PM -0800, Chris Wedgwood wrote: > With 2.6.24-rc2 (amd64) I sometimes (usually but perhaps not always) > see a hang when accessing some NFS exported XFS filesystems. Local > access to these filesystems ahead of time works without problems. > > This does not occur with 2.6.23.1. The filesystem does not appear to > be corrupt. >
> [ 1462.911360] ffffffff80744020 ffffffff80746dc0 ffff81010129c140 > ffff8101000ad100 > [ 1462.911391] Call Trace: > [ 1462.911417] [<ffffffff8052e638>] __down+0xe9/0x101 > [ 1462.911437] [<ffffffff8022cc80>] default_wake_function+0x0/0xe > [ 1462.911458] [<ffffffff8052e275>] __down_failed+0x35/0x3a > [ 1462.911480] [<ffffffff8035ac25>] _xfs_buf_find+0x84/0x24d > [ 1462.911501] [<ffffffff8035ad34>] _xfs_buf_find+0x193/0x24d > [ 1462.911522] [<ffffffff803599b1>] xfs_buf_lock+0x43/0x45 this is bp->b_sema which lookup wants. > [ 1462.915534] [<ffffffff8032b6da>] xfs_readdir+0x91/0xb6 > [ 1462.915557] [<ffffffff8030415b>] nfs3svc_encode_entry_plus+0x0/0x13 > [ 1462.915579] [<ffffffff8035be9d>] xfs_file_readdir+0x31/0x40 > [ 1462.915599] [<ffffffff8028c9f8>] vfs_readdir+0x61/0x93 > [ 1462.915619] [<ffffffff8030415b>] nfs3svc_encode_entry_plus+0x0/0x13 > [ 1462.915642] [<ffffffff802fc78e>] nfsd_readdir+0x6d/0xc5 and this is the nasty nfsd case where a filldir callback calls back into lookup. I suspect we're somehow holding b_sema already. Previously this was okay because we weren't inside the actualy readdir code when calling filldir but operate on a copy of the data. This gem has bitten other filesystem before, I'll see if I can find a way around it. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
