Re: [mm] aae2359b1a: BUG:Bad_rss-counter_state_mm:#type:MM_ANONPAGES_val

[Hugh Dickins]

On Fri, 11 Mar 2022, kernel test robot wrote:
> 
> Greeting,
> 
> FYI, we noticed the following commit (built with gcc-9):
> 
> commit: aae2359b1a514180633c4a4e6666c91e44a928c8 ("mm: thp: don't have to lock page anymore when splitting PMD")

Yes, known bad patch, replaced by good patch a day or two later.

> url: https://github.com/0day-ci/linux/commits/Qianggui-Song/arm64-dts-meson-s4-add-gpio_intc-node/20220310-172923
> 
> in testcase: trinity
> version: trinity-static-i386-x86_64-f93256fb_2019-08-28
> with following parameters:
> 
> 	runtime: 300s
> 	group: group-01
> 
> test-description: Trinity is a linux system call fuzz tester.
> test-url: http://codemonkey.org.uk/projects/trinity/
> 
> 
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
> 
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
> 
> 
> 
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> 
> 
> [   20.947643][ T4079] mm/pgtable-generic.c:51: bad pmd e7d8e333(8000000433c000c5)
> [   20.949757][  T427] BUG: Bad rss-counter state mm:84638533 type:MM_ANONPAGES val:512
> [   20.951030][  T427] BUG: non-zero pgtables_bytes on freeing mm: 4096
> [   20.960329][ T4080] mm/pgtable-generic.c:51: bad pmd 6dc594d8(8000000433c000c5)
> [   20.961775][  T427] BUG: Bad rss-counter state mm:bf324b3f type:MM_ANONPAGES val:512
> [   20.963109][  T427] BUG: non-zero pgtables_bytes on freeing mm: 4096
> [   20.974600][ T4081] mm/pgtable-generic.c:51: bad pmd d1c9ec63(8000000433c000c5)
> [   20.977758][  T427] BUG: Bad rss-counter state mm:e038d31c type:MM_ANONPAGES val:512
> [   20.978918][  T427] BUG: non-zero pgtables_bytes on freeing mm: 4096
> [   20.982960][ T4082] mm/pgtable-generic.c:51: bad pmd 8d2043e0(8000000433c000c5)
> [   20.994138][ T4083] BUG: Bad rss-counter state mm:890a50d8 type:MM_ANONPAGES val:512
> [   20.995441][ T4083] BUG: non-zero pgtables_bytes on freeing mm: 4096
> [   20.997140][ T4083] mm/pgtable-generic.c:51: bad pmd 78b279e7(8000000433c000c5)
> [   21.088268][ T3649] BUG: Bad rss-counter state mm:10e6eb4f type:MM_ANONPAGES val:512
> [   21.089552][ T3649] BUG: non-zero pgtables_bytes on freeing mm: 4096