Bugzilla – Bug 1185352
exfat: ERROR: invalid VBR checksum 0xc746d7e6 (expected 0x8122115) on zram test
Last modified: 2021-05-04 16:34:06 UTC
Created attachment 848788 [details]
dmesg from failing machine (https://openqa.opensuse.org/tests/1713946/file/serial0.txt)
LTP zram01 test triggers failure on exfat :
FUSE exfat 1.3.0
ERROR: invalid VBR checksum 0xc746d7e6 (expected 0x8122115).
zram01 6 TBROK: mount /dev/zram6 zram6 failed
I don't see anything suspicious in dmesg, not in test output.
I can provide strace (or whatever you need).
Test started to fail since it's introduction in build 20210419.
Created attachment 848789 [details]
test output (https://openqa.opensuse.org/tests/1713946/file/serial_terminal.txt)
So this is about fuse-exfat, not the exfat module in the kernel, right?
Adding Goldwyn to Cc, as this is a filesystem matter.
(In reply to Takashi Iwai from comment #2)
> So this is about fuse-exfat, not the exfat module in the kernel, right?
> Adding Goldwyn to Cc, as this is a filesystem matter.
Created attachment 849017 [details]
strace of failing command (ROD mount /dev/zram$i zram$i)
Unlike of #1185546 this bug is reproducible, thus I added strace.
Also adding a quicker reproducer example than using LTP:
# modprobe -v zram
# zramctl --size 25M /dev/zram0
# mkfs.exfat /dev/zram0
exfatprogs version : 1.1.0
Creating exFAT filesystem(/dev/zram0, cluster size=4096)
Writing volume boot record: done
Writing backup volume boot record: done
Fat table creation: done
Allocation bitmap creation: done
Upcase table creation: done
Writing root directory entry: done
exFAT format complete!
# mount /dev/zram0 /mnt/
FUSE exfat 1.3.0
ERROR: invalid VBR checksum 0xc74161e6 (expected 0x71fe3afd).
NOTE: I was not able to reproduce it on my laptop with 5.12.1-1.g9bb8944-default using FUSE exfat 1.3.0, maybe it has been fixed in 5.12 (but haven't find anything obvious in kernel git).
I am unable to reproduce this on older kernel either. So I am not sure what was wrong here. There were a couple of changes in zram writebacks which could be the reason.
Closing as UPSTREAM.