Moritz asked that this mainline patch be applied to 3.13-stable: 92a5655 nfs: Don't busy-wait on SIGKILL in __nfs_iocounter_wait Looks like 3.14-stable and 3.16-stable need it too. (3.12 already carries it). My context backport (posted as a follow-up to this) applies to 3.14 and 3.16. Thanks, Moritz and David! -Kamal -------- Forwarded Message -------- From: Moritz Mühlenhoff <muehlenhoff@xxxxxxxxxxxxx> To: Kamal Mostafa <kamal@xxxxxxxxxxxxx> Subject: Patch submission for 3.13.x LTS series Date: Mon, 1 Dec 2014 15:52:30 +0100 Hi Kamal, I saw on LWN that you're the current maintainer of the 3.13 long term kernel, so I'm forwarding this to you: I would like to recommend to merge upstream 92a56555bd576c61b27a5cab9f38a33a1e9a1df5 into the next 3.13 kernel (which applies cleanly). We have a customer who's using home directories stored on NFS file servers running Ubunu 14.04/Trusty. They ran into frequent soft lockups (several times a day) with call traces like this: Sep 5 09:06:33 eg-ts1 kernel: [84231.083825] Call Trace: Sep 5 09:06:33 eg-ts1 kernel: [84231.083832] [<c1090f88>] prepare_to_wait+0x48/0x70 Sep 5 09:06:33 eg-ts1 kernel: [84231.083848] [<f8eccd0f>] nfs_iocounter_wait+0x7f/0xa0 [nfs] Sep 5 09:06:33 eg-ts1 kernel: [84231.083851] [<c1091280>] ? autoremove_wake_function+0x40/0x40 Sep 5 09:06:33 eg-ts1 kernel: [84231.083859] [<f8ec340f>] do_unlk+0x3f/0xb0 [nfs] Sep 5 09:06:33 eg-ts1 kernel: [84231.083868] [<f8ec367d>] nfs_lock+0x11d/0x190 [nfs] Sep 5 09:06:33 eg-ts1 kernel: [84231.083873] [<c1180440>] ? pipe_write+0x330/0x480 Sep 5 09:06:33 eg-ts1 kernel: [84231.083881] [<f8ec3560>] ? do_setlk+0xe0/0xe0 [nfs] Sep 5 09:06:33 eg-ts1 kernel: [84231.083884] [<c11bedb8>] vfs_lock_file+0x18/0x40 Sep 5 09:06:33 eg-ts1 kernel: [84231.083887] [<c11bef10>] do_lock_file_wait.part.19+0x30/0xb0 Sep 5 09:06:33 eg-ts1 kernel: [84231.083889] [<c11c0430>] fcntl_setlk64+0xf0/0x1d0 Sep 5 09:06:33 eg-ts1 kernel: [84231.083893] [<c10b1cd8>] ? ktime_get_ts+0x48/0x140 Sep 5 09:06:33 eg-ts1 kernel: [84231.083896] [<c1188c16>] SyS_fcntl64+0x66/0xd0 Sep 5 09:06:33 eg-ts1 kernel: [84231.083899] [<c165d9cd>] sysenter_do_call+0x12/0x28 Sep 5 09:06:33 eg-ts1 kernel: [84231.083900] Code: 83 e8 01 75 f2 89 c8 89 f2 66 66 90 66 66 90 eb e1 66 90 55 89 e5 53 66 66 66 66 90 89 d3 e9 10 00 00 00 f0 80 00 02 89 d8 50 9d <66> 66 66 90 5b 5d c3 90 0f b7 10 f0 80 00 02 f6 40 01 01 74 e7 Merging 92a56555bd576c61b27a5cab9f38a33a1e9a1df5 into a local build has fixed these problems. The fix by Trond wasn't CCed to stable@kernel, so this might have fallen through the cracks. Cheers, Moritz -- Moritz Mühlenhoff Open Source Software Engineer Univention GmbH be open. Mary-Somerville-Str.1 28359 Bremen Tel. : +49 421 22232-0 [.....] Fax : +49 421 22232-99 muehlenhoff@xxxxxxxxxxxxx http://www.univention.de Geschäftsführer: Peter H. Ganten HRB 20755 Amtsgericht Bremen Steuer-Nr.: 71-597-02876 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html