On 2014/7/21 10:34, Rui Xiang wrote: > On 2014/7/18 17:10, Lukáš Czerner wrote: >> On Wed, 16 Jul 2014, Rui Xiang wrote: >> >>> Date: Wed, 16 Jul 2014 17:28:10 +0800 >>> From: Rui Xiang <rui.xiang@xxxxxxxxxx> >>> To: Lukáš Czerner <lczerner@xxxxxxxxxx> >>> Cc: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>, linux-ext4@xxxxxxxxxxxxxxx, >>> linux-fsdevel@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, >>> Li Zefan <lizefan@xxxxxxxxxx> >>> Subject: Re: testing result of loop-aio patchset on ext3 >>> >>> On 2014/7/16 15:58, Lukáš Czerner wrote: >>>> On Wed, 16 Jul 2014, Rui Xiang wrote: >>>> >>>>> Date: Wed, 16 Jul 2014 11:54:24 +0800 >>>>> From: Rui Xiang <rui.xiang@xxxxxxxxxx> >>>>> To: Lukáš Czerner <lczerner@xxxxxxxxxx> >>>>> Cc: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>, linux-ext4@xxxxxxxxxxxxxxx, >>>>> linux-fsdevel@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, >>>>> Li Zefan <lizefan@xxxxxxxxxx> >>>>> Subject: Re: testing result of loop-aio patchset on ext3 >>>>> >>>>> On 2014/7/14 17:51, Lukáš Czerner wrote: >>>>>> On Mon, 14 Jul 2014, Rui Xiang wrote: >>>>>> >>>>>>> Date: Mon, 14 Jul 2014 17:34:38 +0800 >>>>>>> From: Rui Xiang <rui.xiang@xxxxxxxxxx> >>>>>>> To: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>, linux-ext4@xxxxxxxxxxxxxxx >>>>>>> Cc: linux-fsdevel@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, >>>>>>> Li Zefan <lizefan@xxxxxxxxxx> >>>>>>> Subject: testing result of loop-aio patchset on ext3 >>>>>>> >>>>>>> Hi Dave, >>>>>>> >>>>>>> We export a container image file as a block device via loop device, but we >>>>>>> found it's very easy that the container rootfs gets corrupted due to power >>>>>>> loss. >>>>>>> >>>>>>> Your early version of loop-aio patchset said the patchset can make loop >>>>>>> mounted filesystems recoverable(lkml.org/lkml/2012/3/30/317), but we found >>>>>>> it doesn't help. >>>>>>> >>>>>>> Both the guest fs and host fs are ext3. >>>>>>> >>>>>>> The loop-aio patchset is from: >>>>>>> git://github.com/kleikamp/linux-shaggy.git aio_loop >>>>>>> >>>>>>> Steps: >>>>>>> 1. dd a 10G image, mkfs.ext3, >>>>>>> # dd if=/dev/zero of=./raw_image bs=1M count=10000 >>>>>>> # echo y | mkfs.ext3 raw_image >>>>>>> >>>>>>> 2. losetup a loop device, mount at ./test_dir >>>>>>> # losetup /dev/loop1 raw_image >>>>>>> # mount /dev/loop1 ./test_dir >>>>>>> >>>>>>> 3. copy fs_mark into test_dir and run >>>>>>> # ./fs_mark -d ./tmp/ -s 102400000 -n 80 >>>>>>> >>>>>>> 4. during runing fs_mark, make systerm reboot indirectly. >>>>>>> # echo b > /proc/sysrq-trigger >>>>>>> >>>>>>> After systerm booted up, sometimes fsck reported raw_image fs has been damaged. >>>>>>> >>>>>>> # fsck.ext3 -n raw_image >>>>>>> e2fsck 1.41.9 (22-Aug-2009) >>>>>>> Warning: skipping journal recovery because doing a read-only filesystem check. >>>>>>> raw_image contains a file system with errors, check forced. >>>>>>> Pass 1: Checking inodes, blocks, and sizes >>>>>>> Pass 2: Checking directory structure >>>>>>> Pass 3: Checking directory connectivity >>>>>>> Pass 4: Checking reference counts >>>>>>> Pass 5: Checking group summary information >>>>>>> Free blocks count wrong (2481348, counted=2480577). >>>>>>> Fix? no >>>>>>> Free inodes count wrong (640837, counted=640835). >>>>>>> Fix? no >>>>>>> raw_image: ********** WARNING: Filesystem still has errors ********** >>>>>>> raw_image: 11/640848 files (0.0% non-contiguous), 78652/2560000 blocks >>>>>> >>>>>> It's not damaged, this is expected result if you're using old >>>>>> e2fsprogs which still treats this as an error. >>>>>> >>>>>> It's not an error because we only update superblock summary at >>>>>> unmount time so with unclean shutdown it's likely that it does not >>>>>> match the reality, but e2fsck can and will easily fix that for you. >>>>>> >>>>>> Please try e2fsprogs v1.42.3 or newer. >>>>>> >>>>> >>>>> Hi Lukas, >>>>> >>>>> I updated e2fsprogs to v1.42.3, and user the newer fsck.ext3 to check raw_image. >>>>> Exactly, the result seemed normal. >>>> >>>> Now I can see that there are much more problems than before, that's >>>> weird. Sorry for not making this clear, but for this kind of >>>> reproducers please use the most recent e2fsprogs. Also , what is the >>>> kernel version you're using in this test ? >>>> >>> >>> I use the most recent e2fsprogs 1.42.11 to check, and the error info is same as >>> result fscked by v1.42.3. It seems that shouldn't be the reason. >>> >>> Otherwise, the kernel version in this test is stable 3.4. >> >> In that case, this is a problem somewhere else. I'll try to >> reproduce and see what I can see. >> >> I assume you're not able to reproduce this on a real device ? >> > > Yes, it only exits on a loop device in my test. > > Otherwise, There was another case in this test: > > I fsck the err image with "-n", the result contains 7 issues. > > # fsck.ext3 -n image1 > Warning: skipping journal recovery because doing a read-only filesystem check. > image1 has been mounted 36 times without being checked, check forced. > Pass 1: Checking inodes, blocks, and sizes > *Inode 16407, i_size is 643005, should be 647168. Fix? no > *Inode 16407, i_blocks is 1264, should be 1272. Fix? no > *Inode 409941, i_blocks is 200208, should be 16688. Fix? no > Pass 2: Checking directory structure > Pass 3: Checking directory connectivity > Pass 4: Checking reference counts > Pass 5: Checking group summary information > *Block bitmap differences: -1643951 +1644741 -(1646592--1646598) +(1648640--1648646) -(1657079--1658102) -(1658104--1659127) -(1659129--1660152) -(1660154--1661177) -(1661179--1662202) -(1662204--1663227) -(1663229--1664252) -(1664254--1665277) -(1665279--1666302) -(1666304--1667327) -(1667329--1668352) -(1668354--1669377) -(1669379--1670402) -(1670404--1671167) -(1671688--1671947) -(1671949--1672972) -(1672974--1673997) -(1673999--1675022) -(1675024--1676047) -(1676049--1677072) -(1677074--1678097) -(1678099--1679122) -(1679124--1680147) -(1680149--1680560) > Fix? no > *Free blocks count wrong for group #2 (31522, counted=31520). > Fix? no > *Free blocks count wrong for group #43 (15870, counted=15871). > Fix? no > *Free blocks count wrong for group #45 (398, counted=396). > Fix? no > *Free blocks count wrong (2203971, counted=2203968). > Fix? no > image1: ********** WARNING: Filesystem still has errors ********** > image1: 13008/655360 files (0.3% non-contiguous), 417469/2621440 blocks > > When I "fsck -y" the image, it seems that only fixes 1 issue. > > # fsck.ext3 -y image1 > image1: recovering journal > image1 has been mounted 36 times without being checked, check forced. > Pass 1: Checking inodes, blocks, and sizes > Pass 2: Checking directory structure > Pass 3: Checking directory connectivity > Pass 4: Checking reference counts > Pass 5: Checking group summary information > *Free blocks count wrong (2203971, counted=2203968). > Fix<y>? yes > image1: ***** FILE SYSTEM WAS MODIFIED ***** > image1: 13008/655360 files (0.3% non-contiguous), 417472/2621440 blocks > > So, I assume journal is revocered before fs checking while doing > "fsck -y", and other issues are fixed during fs revovering journal, > is that? > Hi Lukas, > Thanks! > >> Thanks! >> -Lukas >> >>> >>> >>> Thanks! >>> >>>> Thanks! >>>> -Lukas >>>> >>>>> >>>>> Then, I continue my previous test. And after testing 35 times, "fsck -n" reported image fs >>>>> had been damaged, too. >>>>> >>>>> # fsck.ext3 -n image1 >>>>> e2fsck 1.42.3.wc1 (28-May-2012) >>>>> Warning: skipping journal recovery because doing a read-only filesystem check. >>>>> image1 has been mounted 36 times without being checked, check forced. >>>>> Pass 1: Checking inodes, blocks, and sizes >>>>> Inode 16407, i_size is 597447, should be 602112. Fix? no >>>>> Inode 16407, i_blocks is 1176, should be 1184. Fix? no >>>>> Inode 409941, i_blocks is 200208, should be 112. Fix? no >>>>> Pass 2: Checking directory structure >>>>> Pass 3: Checking directory connectivity >>>>> Pass 4: Checking reference counts >>>>> Pass 5: Checking group summary information >>>>> Block bitmap differences: -1506836 -1506843 -(1506859--1506860) -(1660941--1661964) -(1661966--1671167) -(1671688--1686473) >>>>> Fix? no >>>>> Free blocks count wrong for group #2 (31558, counted=31556). >>>>> Fix? no >>>>> Free blocks count wrong for group #43 (15871, counted=15867). >>>>> Fix? no >>>>> Free blocks count wrong (2204041, counted=2204035). >>>>> Fix? no >>>>> image1: ********** WARNING: Filesystem still has errors ********** >>>>> image1: 13008/655360 files (0.3% non-contiguous), 417399/2621440 blocks >>>>> >>>>> I backup the image to image_bk, and then mount the image to a dir, and cat all files in the image. >>>>> Steps: >>>>> # dd if=image1 of=image_bk >>>>> # mount image1 err_dir >>>>> # find -name '*' -exec cat > /dev/null {} \; >>>>> >>>>> There are no issues during catting, and no err in dmesg too. >>>>> >>>>> *But when I umount the image1 from err_dir, The fsck result didn't show any fs corruption info. >>>>> >>>>> I mount image_bk to err_dir and umount it with no operation directly. The result is same to iamge1. >>>>> >>>>> *So, is fs in the image as a block device via loop device damaged really, or does it have some others issues? >>>>> Could you give me some opinions? >>>>> >>>>> >>>>> Thanks. >>>>> >>>>> >>>>> -- >>>>> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in >>>>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html