blktrace: Concurrent blktraces are not allowed on loop3
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Trying to write to read-only block-device loop3 (partno 0)
WARNING: CPU: 0 PID: 14255 at block/blk-core.c:705 bio_check_ro block/blk-core.c:705 [inline]
WARNING: CPU: 0 PID: 14255 at block/blk-core.c:705 submit_bio_checks+0x1577/0x18d0 block/blk-core.c:833
Modules linked in:
CPU: 0 PID: 14255 Comm: kmmpd-loop3 Not tainted 5.10.56 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:bio_check_ro block/blk-core.c:705 [inline]
RIP: 0010:submit_bio_checks+0x1577/0x18d0 block/blk-core.c:833
Code: 03 00 00 45 8b a4 24 64 05 00 00 48 89 ef 48 8d 74 24 50 e8 6b 36 fe ff 48 c7 c7 a0 51 3a 84 48 89 c6 44 89 e2 e8 18 ca d3 01 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 80 3c 02
RSP: 0018:ffff8880516a7ae8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 1ffff1100a2d4f63 RCX: 0000000000000000
RDX: ffff888051a28000 RSI: ffffffff812930d3 RDI: ffffed100a2d4f4f
RBP: ffff88804610a900 R08: 0000000000000001 R09: ffff88806ce2facf
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: ffff88800cdc8000 R14: ffff88804610a910 R15: ffff88804610a908
FS:  0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ad397c8680 CR3: 000000000d350000 CR4: 0000000000350ef0
Call Trace:
 submit_bio_noacct+0x7a/0xce0 block/blk-core.c:1045
 submit_bio+0xf3/0x4e0 block/blk-core.c:1130
 submit_bh_wbc.constprop.0+0x580/0x770 fs/buffer.c:3054
 write_mmp_block+0x2d0/0x650 fs/ext4/mmp.c:55
 kmmpd+0x3f8/0x9d0 fs/ext4/mmp.c:167
 kthread+0x38f/0x470 kernel/kthread.c:292
 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:296
irq event stamp: 1173
hardirqs last  enabled at (1181): [<ffffffff8128f659>] console_unlock+0x929/0xb30 kernel/printk/printk.c:2552
hardirqs last disabled at (1244): [<ffffffff8128f565>] console_unlock+0x835/0xb30 kernel/printk/printk.c:2467
softirqs last  enabled at (1242): [<ffffffff83e00f92>] asm_call_irq_on_stack+0x12/0x20
softirqs last disabled at (1191): [<ffffffff83e00f92>] asm_call_irq_on_stack+0x12/0x20
---[ end trace 6ae490934b4e6af3 ]---