[loop]efcfec579: BUG:blk_update_request: I/O error, dev loop6, sector 49674 op 0x9:(WRITE_ZEROES)

[loop]efcfec579: BUG:blk_update_request: I/O error, dev loop6, sector 49674 op 0x9:(WRITE_ZEROES)

[Xu, Yanfei]

Hi,

After operating the /dev/loop which losetup with an image placed in tmpfs,

I got the following ERROR messages:

----------------[cut here]---------------------

[  183.110770] blk_update_request: I/O error, dev loop6, sector 524160 
op 0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.123949] blk_update_request: I/O error, dev loop6, sector 522 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.137123] blk_update_request: I/O error, dev loop6, sector 16906 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.150314] blk_update_request: I/O error, dev loop6, sector 32774 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.163551] blk_update_request: I/O error, dev loop6, sector 49674 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.176824] blk_update_request: I/O error, dev loop6, sector 65542 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.190029] blk_update_request: I/O error, dev loop6, sector 82442 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.203281] blk_update_request: I/O error, dev loop6, sector 98310 op 
0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.216531] blk_update_request: I/O error, dev loop6, sector 115210 
op 0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0
[  183.229914] blk_update_request: I/O error, dev loop6, sector 131078 
op 0x9:(WRITE_ZEROES) flags 0x1000800 phys_seg 0 prio class 0


I have found the commit which introduce this issue by git bisect :

     commit :efcfec57[loop: fix no-unmap write-zeroes request behavior]


Kernrel version: Linux version 5.6.0

Frequency: every time

steps to reproduce:

   1.git clone mainline kernel

   2.compile kernel with ARCH=x86_64, and then boot the system with it

     (seems other arch also can reproduce it )

   3.make an image by "dd of=/tmp/image if=/dev/zero bs=1M count=256"

   4.place the image in tmpfs directory

   5.losetup /dev/loop6 /PATH/image

   6.mkfs.ext2 /dev/loop6


Any comments will be appreciated.


Thanks,

Yanfei