On Tue, Jun 07, 2022 at 06:51:27AM +0530, Naresh Kamboju wrote:
On Mon, 6 Jun 2022 at 23:06, Minchan Kim minchan@kernel.org wrote:
On Thu, Jun 02, 2022 at 02:19:34PM +0530, Naresh Kamboju wrote:
The following kernel crash reported while running selftests: zram: zram.sh test case on qemu-arm with Linux mainline v5.18.0 kernel version.
Reported-by: Linux Kernel Functional Testing lkft@linaro.org
Started noticing from kernel crash from BAD: git_sha: cdeffe87f790dfd1baa193020411ce9a538446d7 GOOD: git_sha: babf0bb978e3c9fce6c4eba6b744c8754fd43d8e
# git log --oneline babf0bb978e3c9fce6c4eba6b744c8754fd43d8e..cdeffe87f790dfd1baa193020411ce9a538446d7 -- drivers/block/ 98931dd95fd4 Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 6140ae41effe zram: fix Kconfig dependency warning b3fbd58fcbb1 mm: Kconfig: simplify zswap configuration e7be8d1dd983 zram: remove double compression logic a2ad63daa88b VFS: add FMODE_CAN_ODIRECT file flag 30226b69f876 zram: add a huge_idle writeback mode
Hi Nalesh,
Thanks for the reporting the bug!
I locally ran the test in my x86 KVM machine but couldn't reproduce it. How is it easy to reproduce? Could you help to bisect it?
It works on qemu_x86-64 It is always reproducible in qemu arm32 environment.
steps to reproduce: # Please download and use this rootfs and kernel zImage
rootfs: https://oebuilds.tuxbuild.com/29zhlbEc3EWq2wod9Uy964Bp27q/images/am57xx-evm/... kernel: https://builds.tuxbuild.com/29zhqJJizU2Y7Ka7ArhryUOrNDC/zImage
Boot command, /usr/bin/qemu-system-aarch64 -cpu host,aarch64=off -machine virt-2.10,accel=kvm -nographic -net nic,model=virtio,maaacaddr=BA:DD:AD:CC:09:04 -net tap -m 2048 -monitor none -kernel kernel/zImage --append "console=ttyAMA0 root=/dev/vda rw" -hda rootfs/rpb-console-image-lkft-am57xx-evm-20220601222434.rootfs.ext4 -m 4096 -smp 2
# cd /opt/kselftests/default-in-kernel/zram # ./zram.sh
Allow me sometime I will try to bisect this problem.
Thanks for sharing the info.
I managed to work your rootfs with my local arm build based on the problematic git tip. However, I couldn't suceed to reproduce it.
I needed to build zsmalloc/zram built-in instead of modules Is it related? Hmm,
Yeah, It would be very helpful if you could help to bisect it. Thanks!
=== &< ==== create '1' zram device(s) zram modules already loaded, kernel supports zram-control interface [ 936.188541] zram: Added device: zram1 all zram devices (/dev/zram1~1 successfully created set max_comp_streams to zram device(s) The device attribute max_comp_streams was deprecated in 4.7 set disk size to zram device(s) /sys/block/zram1/disksize = '1048576' zram set disksizes: OK set memory limit to zram device(s) [ 936.214438] zram1: detected capacity change from 0 to 2048 /sys/block/zram1/mem_limit = '1M' zram set memory limit: OK make swap with zram device(s) [ 936.608854] Adding 1020k swap on /dev/zram1. Priority:-2 extents:1 across:1020k SS done with /dev/zram1 zram making zram mkswap and swapon: OK zram swapoff: OK zram cleanup [ 937.063416] zram1: detected capacity change from 2048 to 0 [ 937.189223] zram: Removed device: zram1 zram02 : [PASS] root@am57xx-evm:/opt/kselftests/default-in-kernel/zram# uname -r 5.18.0-11934-g54eb8462f21f