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From: CAI Qian <caiqian@redhat.com>
To: tj <tj@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Dave Chinner <david@fromorbit.com>,
	linux-xfs <linux-xfs@vger.kernel.org>,
	Jens Axboe <axboe@kernel.dk>, Nick Piggin <npiggin@gmail.com>,
	linux-fsdevel@vger.kernel.org
Subject: Re: local DoS - systemd hang or timeout (WAS: Re: [RFC][CFT] splice_read reworked)
Date: Wed, 5 Oct 2016 14:57:04 -0400 (EDT)
Message-ID: <874538236.682217.1475693824077.JavaMail.zimbra@redhat.com> (raw)
In-Reply-To: <270577901.647921.1475682888765.JavaMail.zimbra@redhat.com>



----- Original Message -----
> From: "CAI Qian" <caiqian@redhat.com>
> To: "tj" <tj@kernel.org>
> Cc: "Al Viro" <viro@ZenIV.linux.org.uk>, "Linus Torvalds" <torvalds@linux-foundation.org>, "Dave Chinner"
> <david@fromorbit.com>, "linux-xfs" <linux-xfs@vger.kernel.org>, "Jens Axboe" <axboe@kernel.dk>, "Nick Piggin"
> <npiggin@gmail.com>, linux-fsdevel@vger.kernel.org
> Sent: Wednesday, October 5, 2016 11:54:48 AM
> Subject: Re: local DoS - systemd hang or timeout (WAS: Re: [RFC][CFT] splice_read reworked)
> 
> 
> 
> ----- Original Message -----
> > From: "tj" <tj@kernel.org>
> > To: "CAI Qian" <caiqian@redhat.com>
> > Cc: "Al Viro" <viro@ZenIV.linux.org.uk>, "Linus Torvalds"
> > <torvalds@linux-foundation.org>, "Dave Chinner"
> > <david@fromorbit.com>, "linux-xfs" <linux-xfs@vger.kernel.org>, "Jens
> > Axboe" <axboe@kernel.dk>, "Nick Piggin"
> > <npiggin@gmail.com>, linux-fsdevel@vger.kernel.org
> > Sent: Wednesday, October 5, 2016 11:30:14 AM
> > Subject: Re: local DoS - systemd hang or timeout (WAS: Re: [RFC][CFT]
> > splice_read reworked)
> > 
> > Hello, CAI.
> > 
> > On Wed, Oct 05, 2016 at 10:09:39AM -0400, CAI Qian wrote:
> > > > This one seems to be the offender.  cgroup is trying to offline a
> > > > cpuset css, which takes place under cgroup_mutex.  The offlining ends
> > > > up trying to drain active usages of a sysctl table which apprently is
> > > > not happening.  Did something hang or crash while trying to generate
> > > > sysctl content?
> > >
> > > Hmm, I am not sure, since the trinity was running from an non-privileged
> > > user which can only read content from /proc or /sys.
> > 
> > So, userland, priviledged or not, can't cause this.  The ref is held
> > only while the kernel code is operating to generate content or
> > iterating, which shouldn't be affected by userland actions.  This is
> > caused by kernel code hanging or crashing while holding a ref.
> Right, the trinity calls many different random syscalls and options on those
> /proc/ and /sys/ files and generate lots of different errno. It is likely
> some of error-path out there causes hang or crash.
Tejun,

Not sure if this related, and there is always a lockdep regards procfs happened
below unless masking by other lockdep issues before the cgroup hang. Also, this
hang is always reproducible.

[ 4787.875980] 
[ 4787.877645] ======================================================
[ 4787.884540] [ INFO: possible circular locking dependency detected ]
[ 4787.891533] 4.8.0-rc8-usrns-scale+ #8 Tainted: G        W      
[ 4787.898138] -------------------------------------------------------
[ 4787.905130] trinity-c116/106905 is trying to acquire lock:
[ 4787.911251]  (&p->lock){+.+.+.}, at: [<ffffffff812aca8c>] seq_read+0x4c/0x3e0
[ 4787.919264] 
[ 4787.919264] but task is already holding lock:
[ 4787.925773]  (sb_writers#8){.+.+.+}, at: [<ffffffff81284367>] __sb_start_write+0xb7/0xf0
[ 4787.934854] 
[ 4787.934854] which lock already depends on the new lock.
[ 4787.934854] 
[ 4787.943981] 
[ 4787.943981] the existing dependency chain (in reverse order) is:
[ 4787.952333] 
-> #3 (sb_writers#8){.+.+.+}:
[ 4787.957050]        [<ffffffff810fd711>] __lock_acquire+0x3f1/0x7f0
[ 4787.963960]        [<ffffffff810fe166>] lock_acquire+0xd6/0x240
[ 4787.970577]        [<ffffffff810f769a>] percpu_down_read+0x4a/0xa0
[ 4787.977487]        [<ffffffff81284367>] __sb_start_write+0xb7/0xf0
[ 4787.984395]        [<ffffffff812a8974>] mnt_want_write+0x24/0x50
[ 4787.991110]        [<ffffffffa05049af>] ovl_want_write+0x1f/0x30 [overlay]
[ 4787.998799]        [<ffffffffa05070c2>] ovl_do_remove+0x42/0x4a0 [overlay]
[ 4788.006483]        [<ffffffffa0507536>] ovl_rmdir+0x16/0x20 [overlay]
[ 4788.013682]        [<ffffffff8128d357>] vfs_rmdir+0xb7/0x130
[ 4788.020009]        [<ffffffff81292ed3>] do_rmdir+0x183/0x1f0
[ 4788.026335]        [<ffffffff81293cf2>] SyS_unlinkat+0x22/0x30
[ 4788.032853]        [<ffffffff81003f8c>] do_syscall_64+0x6c/0x1e0
[ 4788.039576]        [<ffffffff817d927f>] return_from_SYSCALL_64+0x0/0x7a
[ 4788.046962] 
-> #2 (&sb->s_type->i_mutex_key#16){++++++}:
[ 4788.053140]        [<ffffffff810fd711>] __lock_acquire+0x3f1/0x7f0
[ 4788.060049]        [<ffffffff810fe166>] lock_acquire+0xd6/0x240
[ 4788.066664]        [<ffffffff817d60e7>] down_read+0x47/0x70
[ 4788.072893]        [<ffffffff8128ce79>] lookup_slow+0xc9/0x200
[ 4788.079410]        [<ffffffff81290b9c>] walk_component+0x1ec/0x310
[ 4788.086315]        [<ffffffff81290e5f>] link_path_walk+0x19f/0x5f0
[ 4788.093219]        [<ffffffff8129151d>] path_openat+0xdd/0xb80
[ 4788.099748]        [<ffffffff81293511>] do_filp_open+0x91/0x100
[ 4788.106362]        [<ffffffff81286f56>] do_open_execat+0x76/0x180
[ 4788.113186]        [<ffffffff8128747b>] open_exec+0x2b/0x50
[ 4788.119404]        [<ffffffff812ec61d>] load_elf_binary+0x28d/0x1120
[ 4788.126511]        [<ffffffff81288487>] search_binary_handler+0x97/0x1c0
[ 4788.134002]        [<ffffffff81289619>] do_execveat_common.isra.36+0x6a9/0x9f0
[ 4788.142071]        [<ffffffff81289c4a>] SyS_execve+0x3a/0x50
[ 4788.148398]        [<ffffffff81003f8c>] do_syscall_64+0x6c/0x1e0
[ 4788.155110]        [<ffffffff817d927f>] return_from_SYSCALL_64+0x0/0x7a
[ 4788.162502] 
-> #1 (&sig->cred_guard_mutex){+.+.+.}:
[ 4788.168179]        [<ffffffff810fd711>] __lock_acquire+0x3f1/0x7f0
[ 4788.175085]        [<ffffffff810fe166>] lock_acquire+0xd6/0x240
[ 4788.181712]        [<ffffffff817d4557>] mutex_lock_killable_nested+0x87/0x500
[ 4788.189695]        [<ffffffff81099599>] mm_access+0x29/0xa0
[ 4788.195924]        [<ffffffff81302b6c>] proc_pid_auxv+0x1c/0x70
[ 4788.202540]        [<ffffffff813039d0>] proc_single_show+0x50/0x90
[ 4788.209445]        [<ffffffff812acb48>] seq_read+0x108/0x3e0
[ 4788.215774]        [<ffffffff8127fb07>] __vfs_read+0x37/0x150
[ 4788.222198]        [<ffffffff81280d35>] vfs_read+0x95/0x140
[ 4788.228425]        [<ffffffff81282268>] SyS_read+0x58/0xc0
[ 4788.234557]        [<ffffffff81003f8c>] do_syscall_64+0x6c/0x1e0
[ 4788.241268]        [<ffffffff817d927f>] return_from_SYSCALL_64+0x0/0x7a
[ 4788.248660] 
-> #0 (&p->lock){+.+.+.}:
[ 4788.252987]        [<ffffffff810fc062>] validate_chain.isra.37+0xe72/0x1150
[ 4788.260769]        [<ffffffff810fd711>] __lock_acquire+0x3f1/0x7f0
[ 4788.267676]        [<ffffffff810fe166>] lock_acquire+0xd6/0x240
[ 4788.274302]        [<ffffffff817d3807>] mutex_lock_nested+0x77/0x430
[ 4788.281406]        [<ffffffff812aca8c>] seq_read+0x4c/0x3e0
[ 4788.287633]        [<ffffffff81316b39>] kernfs_fop_read+0x129/0x1b0
[ 4788.294659]        [<ffffffff8127fca3>] do_loop_readv_writev+0x83/0xc0
[ 4788.301954]        [<ffffffff812811a8>] do_readv_writev+0x218/0x240
[ 4788.308959]        [<ffffffff81281209>] vfs_readv+0x39/0x50
[ 4788.315188]        [<ffffffff812bc6b1>] default_file_splice_read+0x1a1/0x2b0
[ 4788.323070]        [<ffffffff812bc206>] do_splice_to+0x76/0x90
[ 4788.329587]        [<ffffffff812bc2db>] splice_direct_to_actor+0xbb/0x220
[ 4788.337173]        [<ffffffff812bc4d8>] do_splice_direct+0x98/0xd0
[ 4788.344078]        [<ffffffff81281dd1>] do_sendfile+0x1d1/0x3b0
[ 4788.350694]        [<ffffffff812829c9>] SyS_sendfile64+0xc9/0xd0
[ 4788.357405]        [<ffffffff81003f8c>] do_syscall_64+0x6c/0x1e0
[ 4788.364119]        [<ffffffff817d927f>] return_from_SYSCALL_64+0x0/0x7a
[ 4788.371511] 
[ 4788.371511] other info that might help us debug this:
[ 4788.371511] 
[ 4788.380443] Chain exists of:
  &p->lock --> &sb->s_type->i_mutex_key#16 --> sb_writers#8

[ 4788.389881]  Possible unsafe locking scenario:
[ 4788.389881] 
[ 4788.396497]        CPU0                    CPU1
[ 4788.401549]        ----                    ----
[ 4788.406614]   lock(sb_writers#8);
[ 4788.410352]                                lock(&sb->s_type->i_mutex_key#16);
[ 4788.418354]                                lock(sb_writers#8);
[ 4788.424902]   lock(&p->lock);
[ 4788.428229] 
[ 4788.428229]  *** DEADLOCK ***
[ 4788.428229] 
[ 4788.434836] 1 lock held by trinity-c116/106905:
[ 4788.439888]  #0:  (sb_writers#8){.+.+.+}, at: [<ffffffff81284367>] __sb_start_write+0xb7/0xf0
[ 4788.449473] 
[ 4788.449473] stack backtrace:
[ 4788.454334] CPU: 16 PID: 106905 Comm: trinity-c116 Tainted: G        W       4.8.0-rc8-usrns-scale+ #8
[ 4788.464719] Hardware name: Intel Corporation S2600WTT/S2600WTT, BIOS GRNDSDP1.86B.0044.R00.1501191641 01/19/2015
[ 4788.476076]  0000000000000086 00000000cbfc6314 ffff8803ce78b760 ffffffff813d5e93
[ 4788.484371]  ffffffff82a3fbd0 ffffffff82a94890 ffff8803ce78b7a0 ffffffff810fa6ec
[ 4788.492663]  ffff8803ce78b7e0 ffff8802ead08000 0000000000000001 ffff8802ead08ca0
[ 4788.500966] Call Trace:
[ 4788.503694]  [<ffffffff813d5e93>] dump_stack+0x85/0xc2
[ 4788.509426]  [<ffffffff810fa6ec>] print_circular_bug+0x1ec/0x260
[ 4788.516128]  [<ffffffff810fc062>] validate_chain.isra.37+0xe72/0x1150
[ 4788.523319]  [<ffffffff811d4491>] ? ___perf_sw_event+0x171/0x290
[ 4788.530022]  [<ffffffff810fd711>] __lock_acquire+0x3f1/0x7f0
[ 4788.536335]  [<ffffffff810fe166>] lock_acquire+0xd6/0x240
[ 4788.542359]  [<ffffffff812aca8c>] ? seq_read+0x4c/0x3e0
[ 4788.548188]  [<ffffffff812aca8c>] ? seq_read+0x4c/0x3e0
[ 4788.554019]  [<ffffffff817d3807>] mutex_lock_nested+0x77/0x430
[ 4788.560528]  [<ffffffff812aca8c>] ? seq_read+0x4c/0x3e0
[ 4788.566358]  [<ffffffff812aca8c>] seq_read+0x4c/0x3e0
[ 4788.571995]  [<ffffffff81316a10>] ? kernfs_fop_open+0x3a0/0x3a0
[ 4788.578600]  [<ffffffff81316b39>] kernfs_fop_read+0x129/0x1b0
[ 4788.585012]  [<ffffffff81316a10>] ? kernfs_fop_open+0x3a0/0x3a0
[ 4788.591617]  [<ffffffff8127fca3>] do_loop_readv_writev+0x83/0xc0
[ 4788.598318]  [<ffffffff81316a10>] ? kernfs_fop_open+0x3a0/0x3a0
[ 4788.604924]  [<ffffffff812811a8>] do_readv_writev+0x218/0x240
[ 4788.611347]  [<ffffffff813e9535>] ? push_pipe+0xd5/0x190
[ 4788.617278]  [<ffffffff813ecec0>] ? iov_iter_get_pages_alloc+0x250/0x400
[ 4788.624746]  [<ffffffff81281209>] vfs_readv+0x39/0x50
[ 4788.630381]  [<ffffffff812bc6b1>] default_file_splice_read+0x1a1/0x2b0
[ 4788.637668]  [<ffffffff8134ae20>] ? security_file_permission+0xa0/0xc0
[ 4788.644954]  [<ffffffff812bc206>] do_splice_to+0x76/0x90
[ 4788.650880]  [<ffffffff812bc2db>] splice_direct_to_actor+0xbb/0x220
[ 4788.657872]  [<ffffffff812bba80>] ? generic_pipe_buf_nosteal+0x10/0x10
[ 4788.665157]  [<ffffffff812bc4d8>] do_splice_direct+0x98/0xd0
[ 4788.671472]  [<ffffffff81281dd1>] do_sendfile+0x1d1/0x3b0
[ 4788.677499]  [<ffffffff812829c9>] SyS_sendfile64+0xc9/0xd0
[ 4788.683622]  [<ffffffff81003f8c>] do_syscall_64+0x6c/0x1e0
[ 4788.689744]  [<ffffffff817d927f>] entry_SYSCALL64_slow_path+0x25/0x25

  reply index

Thread overview: 101+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20160908235521.GL2356@ZenIV.linux.org.uk>
     [not found] ` <20160909015324.GD30056@dastard>
     [not found]   ` <CA+55aFzohsUXj_3BeFNr2t50Wm=G+7toRDEz=Tk7VJqP3n1hXQ@mail.gmail.com>
     [not found]     ` <CA+55aFxrqCng2Qxasc9pyMrKUGFjo==fEaFT1vkH9Lncte3RgQ@mail.gmail.com>
     [not found]       ` <20160909023452.GO2356@ZenIV.linux.org.uk>
     [not found]         ` <CA+55aFwHQMjO4-vtfB9-ytc=o+DRo-HXVGckvXLboUxgpwb7_g@mail.gmail.com>
     [not found]           ` <20160909221945.GQ2356@ZenIV.linux.org.uk>
     [not found]             ` <CA+55aFzTOOB6oEVaaGD0N7Uznk-W9+ULPwzsxS_L_oZqGVSeLA@mail.gmail.com>
     [not found]               ` <20160914031648.GB2356@ZenIV.linux.org.uk>
     [not found]                 ` <20160914133925.2fba4629@roar.ozlabs.ibm.com>
2016-09-18  5:33                   ` xfs_file_splice_read: possible circular locking dependency detected Al Viro
2016-09-19  3:08                     ` Nicholas Piggin
2016-09-19  6:11                       ` Al Viro
2016-09-19  7:26                         ` Nicholas Piggin
     [not found]                 ` <CA+55aFznQaOWoSMNphgGJJWZ=8-odrc0DAUMzfGPQe+_N4UgNA@mail.gmail.com>
     [not found]                   ` <20160914042559.GC2356@ZenIV.linux.org.uk>
     [not found]                     ` <20160917082007.GA6489@ZenIV.linux.org.uk>
     [not found]                       ` <20160917190023.GA8039@ZenIV.linux.org.uk>
2016-09-18 19:31                         ` skb_splice_bits() and large chunks in pipe (was " Al Viro
2016-09-18 20:12                           ` Linus Torvalds
2016-09-18 22:31                             ` Al Viro
2016-09-19  0:18                               ` Linus Torvalds
2016-09-23 19:00                         ` [RFC][CFT] splice_read reworked Al Viro
2016-09-23 19:01                           ` [PATCH 01/11] fix memory leaks in tracing_buffers_splice_read() Al Viro
2016-09-23 19:02                           ` [PATCH 02/11] splice_to_pipe(): don't open-code wakeup_pipe_readers() Al Viro
2016-09-23 19:02                           ` [PATCH 03/11] splice: switch get_iovec_page_array() to iov_iter Al Viro
2016-09-23 19:03                           ` [PATCH 04/11] splice: lift pipe_lock out of splice_to_pipe() Al Viro
2016-09-23 19:45                             ` Linus Torvalds
2016-09-23 20:10                               ` Al Viro
2016-09-23 20:36                                 ` Linus Torvalds
2016-09-24  3:59                                   ` Al Viro
2016-09-24 17:29                                     ` Al Viro
2016-09-27 15:38                                       ` Nicholas Piggin
2016-09-27 15:53                                       ` Chuck Lever
2016-09-24  3:59                                   ` [PATCH 04/12] " Al Viro
2016-09-26 13:35                                     ` Miklos Szeredi
2016-09-27  4:14                                       ` Al Viro
2016-12-17 19:54                                     ` Andreas Schwab
2016-12-18 19:28                                       ` Linus Torvalds
2016-12-18 19:57                                         ` Andreas Schwab
2016-12-18 20:12                                         ` Al Viro
2016-12-18 20:30                                           ` Al Viro
2016-12-18 22:10                                             ` Linus Torvalds
2016-12-18 22:18                                               ` Al Viro
2016-12-18 22:22                                                 ` Linus Torvalds
2016-12-18 22:49                                               ` Andreas Schwab
2016-12-21 18:56                                               ` Andreas Schwab
2016-12-21 19:12                                                 ` Linus Torvalds
2016-09-24  4:00                                   ` [PATCH 06/12] new helper: add_to_pipe() Al Viro
2016-09-26 13:49                                     ` Miklos Szeredi
2016-09-24  4:01                                   ` [PATCH 10/12] new iov_iter flavour: pipe-backed Al Viro
2016-09-29 20:53                                     ` Miklos Szeredi
2016-09-29 22:50                                       ` Al Viro
2016-09-30  7:30                                         ` Miklos Szeredi
2016-10-03  3:34                                           ` [RFC] O_DIRECT vs EFAULT (was Re: [PATCH 10/12] new iov_iter flavour: pipe-backed) Al Viro
2016-10-03 17:07                                             ` Linus Torvalds
2016-10-03 18:54                                               ` Al Viro
2016-09-24  4:01                                   ` [PATCH 11/12] switch generic_file_splice_read() to use of ->read_iter() Al Viro
2016-09-24  4:02                                   ` [PATCH 12/12] switch default_file_splice_read() to use of pipe-backed iov_iter Al Viro
2016-09-23 19:03                           ` [PATCH 05/11] skb_splice_bits(): get rid of callback Al Viro
2016-09-23 19:04                           ` [PATCH 06/11] new helper: add_to_pipe() Al Viro
2016-09-23 19:04                           ` [PATCH 07/11] fuse_dev_splice_read(): switch to add_to_pipe() Al Viro
2016-09-23 19:06                           ` [PATCH 08/11] cifs: don't use memcpy() to copy struct iov_iter Al Viro
2016-09-23 19:08                           ` [PATCH 09/11] fuse_ioctl_copy_user(): don't open-code copy_page_{to,from}_iter() Al Viro
2016-09-26  9:31                             ` Miklos Szeredi
2016-09-23 19:09                           ` [PATCH 10/11] new iov_iter flavour: pipe-backed Al Viro
2016-09-23 19:10                           ` [PATCH 11/11] switch generic_file_splice_read() to use of ->read_iter() Al Viro
2016-09-30 13:32                           ` [RFC][CFT] splice_read reworked CAI Qian
2016-09-30 17:42                             ` CAI Qian
2016-09-30 18:33                               ` CAI Qian
2016-10-03  1:37                                 ` Al Viro
2016-10-03 17:49                                   ` CAI Qian
2016-10-04 17:39                                     ` local DoS - systemd hang or timeout (WAS: Re: [RFC][CFT] splice_read reworked) CAI Qian
2016-10-04 21:42                                       ` tj
2016-10-05 14:09                                         ` CAI Qian
2016-10-05 15:30                                           ` tj
2016-10-05 15:54                                             ` CAI Qian
2016-10-05 18:57                                               ` CAI Qian [this message]
2016-10-05 20:05                                                 ` Al Viro
2016-10-06 12:20                                                   ` CAI Qian
2016-10-06 12:25                                                     ` CAI Qian
2016-10-06 16:11                                                       ` CAI Qian
2016-10-06 17:00                                                         ` Linus Torvalds
2016-10-06 18:12                                                           ` CAI Qian
2016-10-07  9:57                                                           ` Dave Chinner
2016-10-07 15:25                                                             ` Linus Torvalds
2016-10-07  7:08                                                       ` Jan Kara
2016-10-07 14:43                                                         ` CAI Qian
2016-10-07 15:27                                                           ` CAI Qian
2016-10-07 18:56                                                             ` CAI Qian
2016-10-09 21:54                                                               ` Dave Chinner
2016-10-10 14:10                                                                 ` CAI Qian
2016-10-10 20:14                                                                   ` CAI Qian
2016-10-10 21:57                                                                   ` Dave Chinner
2016-10-12 19:50                                                                     ` [bisected] " CAI Qian
2016-10-12 20:59                                                                       ` Dave Chinner
2016-10-13 16:25                                                                         ` CAI Qian
2016-10-13 20:49                                                                           ` Dave Chinner
2016-10-13 20:56                                                                             ` CAI Qian
2016-10-09 21:51                                                           ` Dave Chinner
2016-10-21 15:38                                                         ` [4.9-rc1+] overlayfs lockdep CAI Qian
2016-10-24 12:57                                                           ` Miklos Szeredi
2016-10-07  9:27                                                     ` local DoS - systemd hang or timeout (WAS: Re: [RFC][CFT] splice_read reworked) Dave Chinner
2016-10-03  1:42                               ` [RFC][CFT] splice_read reworked Al Viro
2016-10-03 14:06                                 ` CAI Qian
2016-10-03 15:20                                   ` CAI Qian
2016-10-03 21:12                                     ` Dave Chinner
2016-10-04 13:57                                       ` CAI Qian
2016-10-03 20:32                                   ` CAI Qian
2016-10-03 20:35                                     ` Al Viro
2016-10-04 13:29                                       ` CAI Qian
2016-10-04 14:28                                         ` Al Viro
2016-10-04 16:21                                           ` CAI Qian
2016-10-04 20:12                                             ` Al Viro
2016-10-05 14:30                                               ` CAI Qian
2016-10-05 16:07                                                 ` Al Viro
2016-09-19  0:22 skb_splice_bits() and large chunks in pipe (was Re: xfs_file_splice_read: possible circular locking dependency detected Al Viro
2016-09-20  9:51 ` Herbert Xu

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    --to=caiqian@redhat.com \
    --cc=axboe@kernel.dk \
    --cc=david@fromorbit.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-xfs@vger.kernel.org \
    --cc=npiggin@gmail.com \
    --cc=tj@kernel.org \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@ZenIV.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Fsdevel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-fsdevel/0 linux-fsdevel/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-fsdevel linux-fsdevel/ https://lore.kernel.org/linux-fsdevel \
		linux-fsdevel@vger.kernel.org
	public-inbox-index linux-fsdevel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-fsdevel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git