On Tue, Oct 13, 2015 at 8:45 AM, Kinglong Mee <kinglongmee@xxxxxxxxx> wrote: > ping ... > > What's your opinion about this problem ? > > If read/write of block layout file with bad length (res.count != arg.count), > should nfs retry? NFS try to call rpc_restart_call_prepare() right now, > that cause a panic with uninitialized task. The client should not be attempting to read more data than what was requested by the O_DIRECT read request. It should be strictly respecting the boundaries of the user buffer that was supplied. Any idea why this is happening? > > thanks, > Kinglong Mee > > On 9/21/2015 11:22, Kinglong Mee wrote: >> It caused by rpc_restart_call_prepare with an uninitialized task >> for the pnfs do I/O locally without sending any RPC to MDS. >> >> Some debug messages, >> >> [ 1004.001842] bl_read_pagelist enter nr_pages 1 offset 2048 count 2048 >> [ 1004.002110] bl_read_pagelist: pg_offset 2048 >> [ 1004.002370] bl_read_pagelist: pg_len 2048 is_dio >> [ 1004.002617] bl_read_pagelist: pg_len 2048 after do_add_page_to_bio >> [ 1004.002853] bl_read_pagelist: 2048 4096 "(isect << SECTOR_SHIFT) < header->inode->i_size" >> [ 1004.003774] NFS: nfs_pgio_result: 0, (status 0), tk_ops (null) >> [ 1004.003989] --> nfs4_read_done >> [ 1004.004224] nfs_readpage_done: 0 >> [ 1004.004459] nfs_pgio_result: 0 >> [ 1004.004691] nfs_readpage_result: eof 0, res.count 4096, args.count 2048 >> [ 1004.004926] nfs_readpage_retry: tk_ops (null) >> >> Panic messages as, >> >> [ 1004.005170] BUG: unable to handle kernel NULL pointer dereference at (null) >> [ 1004.005452] IP: [<ffffffffa0075f8a>] rpc_restart_call_prepare+0x2a/0x50 [sunrpc] >> [ 1004.005702] PGD 0 >> [ 1004.005937] Oops: 0000 [#1] >> [ 1004.006175] Modules linked in: blocklayoutdriver(OE) nfsv4(OE) nfs(OE) fscache(E) xfs libcrc32c btrfs coretemp crct10dif_pclmul ppdev crc32_pclmul crc32c_intel ghash_clmulni_intel vmw_balloon vmw_vmci parport_pc parport nfsd(OE) shpchp xor raid6_pq i2c_piix4 auth_rpcgss nfs_acl lockd(E) grace sunrpc(E) vmwgfx drm_kms_helper ttm drm serio_raw e1000 mptspi scsi_transport_spi mptscsih ata_generic mptbase pata_acpi [last unloaded: fscache] >> [ 1004.007611] CPU: 0 PID: 3489 Comm: kworker/0:2 Tainted: G OE 4.3.0-rc1+ #252 >> [ 1004.007920] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014 >> [ 1004.008571] Workqueue: events bl_read_cleanup [blocklayoutdriver] >> [ 1004.008917] task: ffff88006ceab080 ti: ffff880017700000 task.ti: ffff880017700000 >> [ 1004.009315] RIP: 0010:[<ffffffffa0075f8a>] [<ffffffffa0075f8a>] rpc_restart_call_prepare+0x2a/0x50 [sunrpc] >> [ 1004.010152] RSP: 0018:ffff880017703cc8 EFLAGS: 00010246 >> [ 1004.010589] RAX: 0000000000000000 RBX: ffff880017726000 RCX: 0000000000000006 >> [ 1004.011007] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8800177260d8 >> [ 1004.011428] RBP: ffff880017703cc8 R08: 0000000000000001 R09: 0000000000000000 >> [ 1004.011831] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8800177260d8 >> [ 1004.012237] R13: ffff8800686008b0 R14: 0000000000000000 R15: ffff880017726160 >> [ 1004.012666] FS: 0000000000000000(0000) GS:ffffffff81c29000(0000) knlGS:0000000000000000 >> [ 1004.013478] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 1004.013930] CR2: 0000000000000000 CR3: 000000006ccbe000 CR4: 00000000001406f0 >> [ 1004.014592] Stack: >> [ 1004.015103] ffff880017703cf0 ffffffffa04c436e ffff8800177260d8 ffff880017726000 >> [ 1004.015611] ffff8800686008b0 ffff880017703d18 ffffffffa04c2fb8 ffff880017726160 >> [ 1004.016105] ffff880017726000 ffff88007ff43100 ffff880017703d40 ffffffffa05349c4 >> [ 1004.016565] Call Trace: >> [ 1004.017071] [<ffffffffa04c436e>] nfs_readpage_result+0x11e/0x130 [nfs] >> [ 1004.017546] [<ffffffffa04c2fb8>] nfs_pgio_result+0x88/0xa0 [nfs] >> [ 1004.018009] [<ffffffffa05349c4>] pnfs_ld_read_done+0x44/0xf0 [nfsv4] >> [ 1004.018469] [<ffffffffa04a8532>] bl_read_cleanup+0x22/0x50 [blocklayoutdriver] >> [ 1004.018938] [<ffffffff810a388c>] process_one_work+0x21c/0x4c0 >> [ 1004.019406] [<ffffffff810a37dd>] ? process_one_work+0x16d/0x4c0 >> [ 1004.019876] [<ffffffff810a3b7a>] worker_thread+0x4a/0x440 >> [ 1004.020339] [<ffffffff810a3b30>] ? process_one_work+0x4c0/0x4c0 >> [ 1004.020795] [<ffffffff810a3b30>] ? process_one_work+0x4c0/0x4c0 >> [ 1004.021289] [<ffffffff810a8d85>] kthread+0xf5/0x110 >> [ 1004.021735] [<ffffffff810a8c90>] ? kthread_create_on_node+0x240/0x240 >> [ 1004.022177] [<ffffffff8172cd1f>] ret_from_fork+0x3f/0x70 >> [ 1004.022604] [<ffffffff810a8c90>] ? kthread_create_on_node+0x240/0x240 >> [ 1004.023025] Code: 00 0f 1f 44 00 00 31 c0 f6 87 e9 00 00 00 01 55 48 89 e5 75 29 48 8b 47 58 48 c7 47 50 80 42 07 a0 c7 87 e4 00 00 00 00 00 00 00 <48> 83 38 00 74 0f 48 c7 47 50 b0 f1 07 a0 b8 01 00 00 00 5d c3 >> [ 1004.024344] RIP [<ffffffffa0075f8a>] rpc_restart_call_prepare+0x2a/0x50 [sunrpc] >> [ 1004.024773] RSP <ffff880017703cc8> >> [ 1004.025228] CR2: 0000000000000000 >> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
