On 07/22/2015 05:15 AM, Richard Weinberger wrote:
Am 21.07.2015 um 10:37 schrieb Dongsheng Yang:
Hi Atem, Richard and others,
This is a patchset to add quota supporting in ubifs.
[1/25] - [7/25] are working to make quotactl to support filesystems
which are running on char device.
Others are about making ubifs to support quota
Please help to review or test it. Any comment is welcome :).
Hi Jan Kara,
I am not sure I am using the quota APIs correctly, please
help to correct me if I am wrong.
Also you can get the code from:
https://github.com/yangdongsheng/linux.git ubifs_quota_v1
My simple testing is shown as below:
I get this lockdep splat. Have you seen it too?
OMG, could you share the script to trigger it?
[ 63.779453]
[ 63.779633] ======================================================
[ 63.780006] [ INFO: possible circular locking dependency detected ]
[ 63.780006] 4.2.0-rc3+ #45 Not tainted
[ 63.780006] -------------------------------------------------------
[ 63.780006] dd/2668 is trying to acquire lock:
[ 63.780006] (&type->s_umount_key#28){+++++.}, at: [<ffffffff81306031>] ubifs_budget_space+0x2c1/0x660
[ 63.780006]
[ 63.780006] but task is already holding lock:
[ 63.780006] (&sb->s_type->i_mutex_key#12){+.+.+.}, at: [<ffffffff811434c5>] generic_file_write_iter+0x35/0x1f0
[ 63.780006]
[ 63.780006] which lock already depends on the new lock.
[ 63.780006]
[ 63.780006]
[ 63.780006] the existing dependency chain (in reverse order) is:
[ 63.780006]
-> #2 (&sb->s_type->i_mutex_key#12){+.+.+.}:
[ 63.780006] [<ffffffff810a2103>] lock_acquire+0xd3/0x270
[ 63.780006] [<ffffffff819cee7b>] mutex_lock_nested+0x6b/0x3a0
[ 63.780006] [<ffffffff81202d23>] vfs_load_quota_inode+0x4f3/0x560
[ 63.780006] [<ffffffff81203203>] dquot_quota_on+0x53/0x60
[ 63.780006] [<ffffffff8120786a>] SyS_quotactl+0x66a/0x890
[ 63.780006] [<ffffffff819d2d57>] entry_SYSCALL_64_fastpath+0x12/0x6f
[ 63.780006]
-> #1 (&s->s_dquot.dqonoff_mutex){+.+...}:
[ 63.780006] [<ffffffff810a2103>] lock_acquire+0xd3/0x270
[ 63.780006] [<ffffffff819cee7b>] mutex_lock_nested+0x6b/0x3a0
[ 63.780006] [<ffffffff81203603>] dquot_writeback_dquots+0x33/0x280
[ 63.780006] [<ffffffff812f2e3e>] ubifs_sync_fs+0x2e/0xb0
[ 63.780006] [<ffffffff811d0d54>] sync_filesystem+0x74/0xb0
[ 63.780006] [<ffffffff8119cf5f>] generic_shutdown_super+0x2f/0x100
[ 63.780006] [<ffffffff8119d281>] kill_anon_super+0x11/0x20
[ 63.780006] [<ffffffff812f22d5>] kill_ubifs_super+0x15/0x30
[ 63.780006] [<ffffffff8119d709>] deactivate_locked_super+0x39/0x70
[ 63.780006] [<ffffffff8119deb9>] deactivate_super+0x49/0x70
[ 63.780006] [<ffffffff811bcb4e>] cleanup_mnt+0x3e/0x90
[ 63.780006] [<ffffffff811bcbed>] __cleanup_mnt+0xd/0x10
[ 63.780006] [<ffffffff81076258>] task_work_run+0x88/0xb0
[ 63.780006] [<ffffffff81003abd>] do_notify_resume+0x3d/0x50
[ 63.780006] [<ffffffff819d2f2c>] int_signal+0x12/0x17
[ 63.780006]
-> #0 (&type->s_umount_key#28){+++++.}:
[ 63.780006] [<ffffffff810a1a17>] __lock_acquire+0x1907/0x1ea0
[ 63.780006] [<ffffffff810a2103>] lock_acquire+0xd3/0x270
[ 63.780006] [<ffffffff819d03cc>] down_read+0x4c/0xa0
[ 63.780006] [<ffffffff81306031>] ubifs_budget_space+0x2c1/0x660
[ 63.780006] [<ffffffff812eef5d>] ubifs_write_begin+0x23d/0x500
[ 63.780006] [<ffffffff81140bda>] generic_perform_write+0xaa/0x1a0
[ 63.780006] [<ffffffff81143433>] __generic_file_write_iter+0x183/0x1e0
[ 63.780006] [<ffffffff81143574>] generic_file_write_iter+0xe4/0x1f0
[ 63.780006] [<ffffffff812eda96>] ubifs_write_iter+0xc6/0x180
[ 63.780006] [<ffffffff8119a958>] __vfs_write+0xa8/0xe0
[ 63.780006] [<ffffffff8119afb7>] vfs_write+0xa7/0x190
[ 63.780006] [<ffffffff8119bcf4>] SyS_write+0x44/0xa0
[ 63.780006] [<ffffffff819d2d57>] entry_SYSCALL_64_fastpath+0x12/0x6f
[ 63.780006]
[ 63.780006] other info that might help us debug this:
[ 63.780006]
[ 63.780006] Chain exists of:
&type->s_umount_key#28 --> &s->s_dquot.dqonoff_mutex --> &sb->s_type->i_mutex_key#12
[ 63.780006] Possible unsafe locking scenario:
[ 63.780006]
[ 63.780006] CPU0 CPU1
[ 63.780006] ---- ----
[ 63.780006] lock(&sb->s_type->i_mutex_key#12);
[ 63.780006] lock(&s->s_dquot.dqonoff_mutex);
[ 63.780006] lock(&sb->s_type->i_mutex_key#12);
[ 63.780006] lock(&type->s_umount_key#28);
[ 63.780006]
[ 63.780006] *** DEADLOCK ***
[ 63.780006]
[ 63.780006] 2 locks held by dd/2668:
[ 63.780006] #0: (sb_writers#8){.+.+.+}, at: [<ffffffff8119b086>] vfs_write+0x176/0x190
[ 63.780006] #1: (&sb->s_type->i_mutex_key#12){+.+.+.}, at: [<ffffffff811434c5>] generic_file_write_iter+0x35/0x1f0
[ 63.780006]
[ 63.780006] stack backtrace:
[ 63.780006] CPU: 2 PID: 2668 Comm: dd Not tainted 4.2.0-rc3+ #45
[ 63.780006] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140816_022509-build35 04/01/2014
[ 63.780006] ffffffff829ef340 ffff880000037988 ffffffff819c4998 0000000000000000
[ 63.780006] ffffffff829f6f40 ffff8800000379d8 ffffffff819c0647 0000000000000002
[ 63.780006] ffff880000037a28 ffff8800000379d8 ffff8800798b97c0 ffff8800798b9fd8
[ 63.780006] Call Trace:
[ 63.780006] [<ffffffff819c4998>] dump_stack+0x4c/0x65
[ 63.780006] [<ffffffff819c0647>] print_circular_bug+0x202/0x213
[ 63.780006] [<ffffffff810a1a17>] __lock_acquire+0x1907/0x1ea0
[ 63.780006] [<ffffffff810a2103>] lock_acquire+0xd3/0x270
[ 63.780006] [<ffffffff81306031>] ? ubifs_budget_space+0x2c1/0x660
[ 63.780006] [<ffffffff819d03cc>] down_read+0x4c/0xa0
[ 63.780006] [<ffffffff81306031>] ? ubifs_budget_space+0x2c1/0x660
[ 63.780006] [<ffffffff819d23c6>] ? _raw_spin_unlock+0x26/0x40
[ 63.780006] [<ffffffff81306031>] ubifs_budget_space+0x2c1/0x660
[ 63.780006] [<ffffffff819cf25b>] ? __mutex_unlock_slowpath+0xab/0x160
[ 63.780006] [<ffffffff812eef5d>] ubifs_write_begin+0x23d/0x500
[ 63.780006] [<ffffffff81140bda>] generic_perform_write+0xaa/0x1a0
[ 63.780006] [<ffffffff81143433>] __generic_file_write_iter+0x183/0x1e0
[ 63.780006] [<ffffffff81143574>] generic_file_write_iter+0xe4/0x1f0
[ 63.780006] [<ffffffff812eda96>] ubifs_write_iter+0xc6/0x180
[ 63.780006] [<ffffffff8119a958>] __vfs_write+0xa8/0xe0
[ 63.780006] [<ffffffff8119afb7>] vfs_write+0xa7/0x190
[ 63.780006] [<ffffffff8119bcf4>] SyS_write+0x44/0xa0
[ 63.780006] [<ffffffff819d2d57>] entry_SYSCALL_64_fastpath+0x12/0x6f
Thanks,
//richard
.
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