sync issues in 4.3-rc1?
From: Artem Bityutskiy
Date: Fri Sep 18 2015 - 12:46:17 EST
Hi,
I observe a problem in 4.3-rc1 which looks like there are issues with
sync - it does not really sync all.
It is Firday night here, and I am dropping a quick report, I did not
spend much time investigating it.
Symptoms:
1. I Run v4.3-rc1 + Fedora 22, most FC22 services disabled, no GUI,
minimal FC22 system, quite silent.
2. I copy a directory with a bunch of files, let's call it "dir". In
my case this is just the kernel modules tree (produces with 'make
modules_install').
3. Run 'halt' or 'poweroff'
4. After the system boots up, very often, but not always, "dir" is
corrupted.
I did not do strict verification, but corruption seems to be that
files are there, but some are corrupted. I checked one file - xfs.ko -
it starts with a bunch of zero bytes, while the original does not
start with zeroes.
I've done this quick test - run the following short shell script with
4.3-rc1 and in 4.2 and get different results. The system is otherwise
the same just kernel is different.
$ while true; do rm -rf ~/4.3.0-rc1/; cp -r /usr/lib/modules/4.3.0-rc1
~/ && sync && grep Dirty /proc/meminfo; done
I get 0's more consistently in case of v4.2. It does not necessary mean
anything, but looks suspicious.
Here are the numbers.
v4.2
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 116 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 456 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 160 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 456 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 72 kB
Dirty: 0 kB
Dirty: 12 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
v4.3-rc1
Dirty: 752 kB
Dirty: 752 kB
Dirty: 60 kB
Dirty: 812 kB
Dirty: 688 kB
Dirty: 0 kB
Dirty: 424 kB
Dirty: 0 kB
Dirty: 632 kB
Dirty: 0 kB
Dirty: 272 kB
Dirty: 272 kB
Dirty: 0 kB
Dirty: 188 kB
Dirty: 940 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 1624 kB
Dirty: 0 kB
Dirty: 424 kB
Dirty: 316 kB
Dirty: 1068 kB
Dirty: 316 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 448 kB
Dirty: 0 kB
Dirty: 752 kB
Dirty: 0 kB
Dirty: 424 kB
Dirty: 0 kB
Dirty: 804 kB
Dirty: 804 kB
Dirty: 804 kB
Dirty: 840 kB
Dirty: 840 kB
Dirty: 888 kB
Dirty: 0 kB
Dirty: 424 kB
Dirty: 112 kB
Dirty: 112 kB
Dirty: 112 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 224 kB
Dirty: 276 kB
Dirty: 276 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 752 kB
Dirty: 872 kB
Dirty: 752 kB
Dirty: 0 kB
Dirty: 448 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 544 kB
Dirty: 544 kB
Dirty: 216 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 448 kB
Dirty: 0 kB
Dirty: 0 kB
Dirty: 0 kB
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/