On Wed Dec 14 11:35:32 2011, Casey Bodley wrote: > On Wed, Dec 14, 2011 at 9:33 AM, Bryan Schumaker <bjschuma@xxxxxxxxxx> wrote: >> On Wed Dec 14 09:07:44 2011, J. Bruce Fields wrote: >>> On Wed, Dec 14, 2011 at 08:42:18AM -0500, Bryan Schumaker wrote: >>>> On Tue Dec 13 17:12:09 2011, J. Bruce Fields wrote: >>>>> On Tue, Dec 13, 2011 at 04:35:58PM -0500, bjschuma@xxxxxxxxxx wrote: >>>>>> From: Bryan Schumaker <bjschuma@xxxxxxxxxx> >>>>>> >>>>>> unhash_delegation() will grab the recall lock before calling >>>>>> list_del_init() in each of these places. This patch removes the >>>>>> redundant calls. >>>>> >>>>> Looks right, thanks. (How did you happen across this?) >>>> >>>> I was looking over the fault injection stuff to see if I can figure out >>>> where an occasional oops was coming from. It seems to happen when I >>>> forget delegations, so I was looking at how other functions release >>>> delegations to see if there was something I missed. The oops doesn't >>>> happen often enough for me to know if this patch fixes it yet, though. >>> >>> Hm, OK. Could you post the oops? >> >> I don't see it in the logs on the server, but I'll keep looking. I'll >> post it the next time I come across it. > > I'm not sure if this is the same oops, but I'm able to reproduce it > consistently against Bruce's 3.2.0-rc1 tree with fault injection > enabled. I use the windows client to read a file, then 'echo 0 > > /sys/kernel/debug/nfsd/forget_delegations'. I just tested with the > patch above, and was able to reproduce the same oops: > > [ 1200.251735] NFSD Fault Injection: forget_delegations (all) > [ 1200.251830] general protection fault: 0000 [#1] SMP > [ 1200.252450] CPU 1 > [ 1200.252597] Modules linked in: > [ 1200.253062] > [ 1200.253256] Pid: 2004, comm: bash Not tainted 3.2.0-rc1+ #9 VMware, > Inc. VMware Virtual Platform/440BX Desktop Reference Platform > [ 1200.254102] RIP: 0010:[<ffffffff811ae7f5>] [<ffffffff811ae7f5>] > nfsd_process_n_delegations+0x3e/0xbe > [ 1200.254746] RSP: 0018:ffff88003b579e08 EFLAGS: 00010287 > [ 1200.255067] RAX: dead000000100100 RBX: 0000000000000000 RCX: 00000001802c002b > [ 1200.255458] RDX: ffff88003d2d3328 RSI: ffffffff811aa49e RDI: ffff88003d2d3308 > [ 1200.255842] RBP: ffff88003b579e58 R08: ffff88003b558000 R09: ffff88003d2d3480 > [ 1200.256226] R10: ffff88003b68b750 R11: 0000000000000040 R12: dead0000001000f8 > [ 1200.256610] R13: 0000000000000001 R14: 000000000000002b R15: 00000000000000d5 > [ 1200.257029] FS: 00007fbad1d44700(0000) GS:ffff88003fa20000(0000) > knlGS:0000000000000000 > [ 1200.257512] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 1200.257850] CR2: 00007fbad1d49000 CR3: 000000003b593000 CR4: 00000000000006e0 > [ 1200.258272] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 1200.258693] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > [ 1200.259083] Process bash (pid: 2004, threadinfo ffff88003b578000, > task ffff88003cc3dfe0) > [ 1200.259561] Stack: > [ 1200.259768] ffffffff811aa49e ffff88003d2d3308 ffffffff81be1560 > ffff88003d2d3328 > [ 1200.260553] ffff88003b579e88 ffffffff81a2b6a0 0000000000000000 > 0000000000000002 > [ 1200.261337] ffff88003d8c1550 ffff88003d8c1528 ffff88003b579e88 > ffffffff811ae897 > [ 1200.262121] Call Trace: > [ 1200.262346] [<ffffffff811aa49e>] ? nfs4_put_delegation+0x55/0x55 > [ 1200.262701] [<ffffffff811ae897>] nfsd_forget_delegations+0x22/0x40 > [ 1200.263119] [<ffffffff8119d3e7>] nfsd_inject_set+0x3f/0x46 > [ 1200.263470] [<ffffffff810fb878>] simple_attr_write+0x8a/0xb2 > [ 1200.263818] [<ffffffff810e0949>] vfs_write+0xa7/0xfa > [ 1200.264136] [<ffffffff810e0b41>] sys_write+0x45/0x69 > [ 1200.264483] [<ffffffff81450f3b>] system_call_fastpath+0x16/0x1b > [ 1200.264832] Code: 45 31 ed 41 54 53 48 89 fb 48 83 ec 28 49 63 c6 > 48 c1 e0 04 4c 8b a0 b0 12 be 81 48 05 b0 12 be 81 48 89 45 c0 49 83 > ec 08 eb 57 > [ 1200.270209] 8b 7c 24 28 49 8d 54 24 28 48 89 55 c8 48 83 ef 20 48 8b 47 > [ 1200.272534] RIP [<ffffffff811ae7f5>] nfsd_process_n_delegations+0x3e/0xbe > [ 1200.273007] RSP <ffff88003b579e08> > [ 1200.273331] ---[ end trace 0071bb3837d120e2 ]--- That's similar to the one I just got. Thanks for the test case! I had been opening two files in order to get a read delegation, I didn't think of trying with just one. Here is what I got: Dec 14 11:21:01 localhost -- MARK -- Dec 14 11:45:00 localhost kernel: [ 7716.735003] NFSD Fault Injection: forget_delegations (all) Dec 14 11:45:00 localhost kernel: [ 7716.735814] CPU 0 Dec 14 11:45:00 localhost kernel: [ 7716.735902] Modules linked in: dm_mod md5 nfsd exportfs nfs lockd fscache auth_rpcgss nfs_acl sunrpc ipv6 ext2 mbcache loop snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_timer psmouse snd serio_raw soundcore pcspkr snd_page_alloc virtio_balloon i2c_piix4 evdev i2c_core floppy processor button btrfs zlib_deflate crc32c libcrc32c sr_mod cdrom pata_acpi uhci_hcd ata_piix usbcore usb_common libata scsi_mod virtio_net virtio_pci virtio_blk virtio_ring virtio Dec 14 11:45:00 localhost kernel: [ 7716.737782] Dec 14 11:45:00 localhost kernel: [ 7716.737782] Pid: 17423, comm: bash Not tainted 3.2.0-rc1-BRYAN+ #1 Bochs Bochs Dec 14 11:45:00 localhost kernel: [ 7716.737782] RIP: 0010:[<ffffffffa0415533>] [<ffffffffa0415533>] nfsd_process_n_delegations+0x53/0xe0 [nfsd] Dec 14 11:45:00 localhost kernel: [ 7716.737782] RSP: 0018:ffff880034121e18 EFLAGS: 00010202 Dec 14 11:45:00 localhost kernel: [ 7716.737782] RAX: dead000000100100 RBX: 0000000000000000 RCX: 0000000000000200 Dec 14 11:45:00 localhost kernel: [ 7716.737782] RDX: dead0000001000f8 RSI: 000060ffc0001270 RDI: ffffea0000d93400 Dec 14 11:45:00 localhost kernel: [ 7716.737782] RBP: ffff880034121e68 R08: ffffffffa040fc26 R09: 0000000000000000 Dec 14 11:45:00 localhost kernel: [ 7716.737782] R10: ffff88002b206a90 R11: 0000000000000000 R12: ffff88002eed4188 Dec 14 11:45:00 localhost kernel: [ 7716.737782] R13: 0000000000000001 R14: ffff88002eed41a8 R15: ffffffffa040fcb0 Dec 14 11:45:00 localhost kernel: [ 7716.737782] FS: 00007f09bfb8c700(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000 Dec 14 11:45:00 localhost kernel: [ 7716.737782] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Dec 14 11:45:00 localhost kernel: [ 7716.737782] CR2: 00007f09bfb92000 CR3: 000000003a90f000 CR4: 00000000000006f0 Dec 14 11:45:00 localhost kernel: [ 7716.737782] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 Dec 14 11:45:00 localhost kernel: [ 7716.737782] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Dec 14 11:45:00 localhost kernel: [ 7716.737782] Process bash (pid: 17423, threadinfo ffff880034120000, task ffff88003c0064a0) Dec 14 11:45:00 localhost kernel: [ 7716.737782] ffffffffa041ffb0 00000000000000f7 ffffffffa04283b0 dead0000001000f8 Dec 14 11:45:00 localhost kernel: [ 7716.737782] ffff880034121e58 0000000000000000 ffffffffa041ffb0 ffff88002eed48d0 Dec 14 11:45:00 localhost kernel: [ 7716.737782] 0000000000000002 ffff88002eed48a8 ffff880034121e88 ffffffffa04155e5 Dec 14 11:45:00 localhost kernel: [ 7716.737782] [<ffffffffa04155e5>] nfsd_forget_delegations+0x25/0x50 [nfsd] Dec 14 11:45:00 localhost kernel: [ 7716.737782] [<ffffffffa03fd75c>] nfsd_inject_set+0x3c/0x70 [nfsd] Dec 14 11:45:00 localhost kernel: [ 7716.737782] [<ffffffff81186f22>] simple_attr_write+0xc2/0xe0 Dec 14 11:45:00 localhost kernel: [ 7716.737782] [<ffffffff811630ef>] vfs_write+0xaf/0x180 Dec 14 11:45:00 localhost kernel: [ 7716.737782] [<ffffffff8116341a>] sys_write+0x4a/0x90 Dec 14 11:45:00 localhost kernel: [ 7716.737782] [<ffffffff81417e42>] system_call_fastpath+0x16/0x1b Dec 14 11:45:00 localhost kernel: [ 7716.737782] RSP <ffff880034121e18> Dec 14 11:45:00 localhost kernel: [ 7716.754976] ---[ end trace f7471c4cb1a3a2f4 ]--- - Bryan > >> >> - Bryan >>> >>> --b. >> >> >> -- >> 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 -- 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
