• Weston Andros Adamson's avatar
    pnfs: fix race in filelayout commit path · d201c4de
    Weston Andros Adamson authored
    Hold the lock while modifying commit info dataserver buckets.
    
    The following oops can be reproduced by running iozone for a while against
    a 2 DS pynfs filelayout server.
    
    general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
    Modules linked in: nfs_layout_nfsv41_files rpcsec_gss_krb5 nfsv4 nfs fscache
    CPU: 0 PID: 903 Comm: iozone Not tainted 3.15.0-rc1-branch-dros_testing+ #44
    Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference
    task: ffff880078164480 ti: ffff88006e972000 task.ti: ffff88006e972000
    RIP: 0010:[<ffffffffa01936e1>]  [<ffffffffa01936e1>] nfs_init_commit+0x22/0x
    RSP: 0018:ffff88006e973d30  EFLAGS: 00010246
    RAX: ffff88006e973e00 RBX: ffff88006e828800 RCX: ffff88006e973e10
    RDX: 0000000000000000 RSI: ffff88006e973e00 RDI: dead4ead00000000
    RBP: ffff88006e973d38 R08: ffff88006e8289d8 R09: 0000000000000000
    R10: ffff88006e8289d8 R11: 0000000000016988 R12: ffff88006e973b98
    R13: ffff88007a0a6648 R14: ffff88006e973e10 R15: ffff88006e828800
    FS:  00007f2ce396b740(0000) GS:ffff88007f200000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007f03278a1000 CR3: 0000000079043000 CR4: 00000000001407f0
    Stack:
    ffff88006e8289d8 ffff88006e973da8 ffffffffa00f144f ffff88006e9478c0
    ffff88006e973e00 ffff88006de21080 0000000100000002 ffff880079be6c48
    ffff88006e973d70 ffff88006e973d70 ffff88006e973e10 ffff88006de21080
    Call Trace:
    [<ffffffffa00f144f>] filelayout_commit_pagelist+0x1ae/0x34a [nfs_layout_nfsv
    [<ffffffffa0194f72>] nfs_generic_commit_list+0x92/0xc4 [nfs]
    [<ffffffffa0195053>] nfs_commit_inode+0xaf/0x114 [nfs]
    [<ffffffffa01892bd>] nfs_file_fsync_commit+0x82/0xbe [nfs]
    [<ffffffffa01ceb0d>] nfs4_file_fsync+0x59/0x9b [nfsv4]
    [<ffffffff8114ee3c>] vfs_fsync_range+0x18/0x20
    [<ffffffff8114ee60>] vfs_fsync+0x1c/0x1e
    [<ffffffffa01891c2>] nfs_file_flush+0x7f/0x84 [nfs]
    [<ffffffff81127a43>] filp_close+0x3c/0x72
    [<ffffffff81140e12>] __close_fd+0x82/0x9a
    [<ffffffff81127a9c>] SyS_close+0x23/0x4c
    [<ffffffff814acd12>] system_call_fastpath+0x16/0x1b
    Code: 5b 41 5c 41 5d 41 5e 5d c3 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 8
    RIP  [<ffffffffa01936e1>] nfs_init_commit+0x22/0xe1 [nfs]
    RSP <ffff88006e973d30>
    ---[ end trace 732fe6419b235e2f ]---
    Suggested-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
    Signed-off-by: default avatarWeston Andros Adamson <dros@primarydata.com>
    Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
    d201c4de
nfs4filelayout.c 37.6 KB