Bug 118041
Summary: | My tricky script involving zram and device mapper hangs on "mount" | ||
---|---|---|---|
Product: | File System | Reporter: | _Vi (vi0oss) |
Component: | ext4 | Assignee: | fs_ext4 (fs_ext4) |
Status: | NEW --- | ||
Severity: | normal | CC: | navinp1912 |
Priority: | P1 | ||
Hardware: | All | ||
OS: | Linux | ||
Kernel Version: | 4.4.8-grsec,4.1.9 | Subsystem: | |
Regression: | No | Bisected commit-id: | |
Attachments: | Stand-alone version of the script which crashes my system |
Description
_Vi
2016-05-11 21:22:20 UTC
What is cryptie4-ff ? it is linear or raid setup for dmsetup. What is hashed_update. Seems like only part of the script is posted. Can you please get a working standalone independent script ? cryptie4-ff: 0 3072000 linear 251:0 672802816 Maybe I'll try to make special stand-alone script for demonstrating the problem. Created attachment 216451 [details]
Stand-alone version of the script which crashes my system
Added the script
Not related to ext4 . I can reproduce this with below script and i think dm-devel@redhat.com should be contacted. I tested on Linux junk-foo 4.2.0-35-generic from Ubuntu (15.10 ) x64. Linux junk-foo 4.2.0-35-generic #40-Ubuntu SMP Tue Mar 15 22:15:45 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux Here is a script that crashes the kernel for me with out of memory. Looks to be a dm problem because it occurs with dd,mkfs.xfs,mkfs.vat ,without zram ie with losetup. Here is the script.Should be run as root for losetup and dmsetup permissions. #!/bin/bash fallocate -l 50M 50M_file_unused fallocate -l 60M 60M_file_unused losetup /dev/loop4 50M_file_unused losetup /dev/loop5 60M_file_unused MS=$(blockdev --getsize /dev/loop4) WS=$(blockdev --getsize /dev/loop5) echo "0 $MS linear /dev/loop4 0 \n $MS $WS linear /dev/loop5 0" | dmsetup create cryptie4-ff DS=$(blockdev --getsize /dev/mapper/cryptie4-ff) MN=$(printf '%d:%d' `stat -Lc '0x%t 0x%T' /dev/loop4`) WN=$(printf '%d:%d' `stat -Lc '0x%t 0x%T' /dev/loop5`) DN=$(printf '%d:%d' `stat -Lc '0x%t 0x%T' /dev/mapper/cryptie4-ff`) #pv /dev/mapper/cryptie4-ff | hashed_update /dev/stdin NULL /dev/zram0 /tmp/ff.md5 65536 pv /dev/mapper/cryptie4-ff dmsetup create ff --table "0 $MS snapshot-origin $MN" After this doing this dd if=/dev/zero of=/dev/mapper/ff or mkfs.xfs /mkfs.ext4 on /dev/mapper/ff will fail. |