kernel warning in get_more_resources

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: d8b15e15 tests/linux: use Akaros's CFLAGS
git tree: akaros
console output: https://syzkaller.appspot.com/x/log.txt?x=107db868d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b018fab5edd31b3
dashboard link: https://syzkaller.appspot.com/bug?extid=09668b5f272c17408f23

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+09668b...@syzkaller.appspotmail.com

kernel warning at kern/src/arena.c:803, from core 1: Excessively rare failure, tell brho
Stack Backtrace on Core 1:
#01 [<0xffffffffc200aa6c>] in backtrace at src/kdebug.c:235
#02 [<0xffffffffc200a294>] in _warn at src/init.c:333
#03 [<0xffffffffc2002d38>] in get_more_resources at src/arena.c:803
#04 [<0xffffffffc200250b>] in arena_alloc at src/arena.c:863
#05 [< [inline] >] in kmem_cache_grow at src/slab.c:852
#05 [<0xffffffffc205409e>] in __kmem_alloc_from_slab at src/slab.c:608
#06 [<0xffffffffc20548da>] in kmem_cache_alloc at src/slab.c:696
#07 [<0xffffffffc2002497>] in arena_alloc at src/arena.c:839
#08 [<0xffffffffc2046675>] in kpages_alloc at src/page_alloc.c:80
#09 [<0xffffffffc200af5e>] in kmalloc at src/kmalloc.c:65
#10 [<0xffffffffc200b01f>] in kzmalloc at src/kmalloc.c:91
#11 [<0xffffffffc207fa69>] in mntralloc at drivers/dev/mnt.c:1120
#12 [<0xffffffffc207fb73>] in mntflushalloc at drivers/dev/mnt.c:1058
#13 [<0xffffffffc2080010>] in mountio at drivers/dev/mnt.c:854
#14 [<0xffffffffc2080105>] in mountrpc at drivers/dev/mnt.c:783
#15 [<0xffffffffc2080f3b>] in mntwalk at drivers/dev/mnt.c:475
#16 [<0xffffffffc2033bcb>] in walk at src/ns/chan.c:800
#17 [<0xffffffffc2034039>] in __namec_from at src/ns/chan.c:1138
#18 [<0xffffffffc2034c43>] in namec at src/ns/chan.c:1530
#19 [<0xffffffffc2041ddd>] in sysopenat at src/ns/sysfile.c:585
#20 [<0xffffffffc20592de>] in sys_openat at src/syscall.c:1826
kernel panic at kern/src/arena.c:810, from core 0: OOM!
Stack Backtrace on Core 0:
#01 [<0xffffffffc200aa6c>] in backtrace at src/kdebug.c:235
#02 [<0xffffffffc200a205>] in _panic at src/init.c:275
#03 [<0xffffffffc2002d17>] in get_more_resources at src/arena.c:810
#04 [<0xffffffffc200250b>] in arena_alloc at src/arena.c:863
#05 [<0xffffffffc2002cb6>] in get_more_resources at src/arena.c:797
#06 [<0xffffffffc200250b>] in arena_alloc at src/arena.c:863
#07 [<0xffffffffc2046675>] in kpages_alloc at src/page_alloc.c:80
#08 [<0xffffffffc20070d0>] in env_setup_vm at src/env.c:50
#09 [<0xffffffffc204b0fe>] in proc_alloc at src/process.c:381
#10 [<0xffffffffc205a423>] in sys_fork at src/syscall.c:897
#11 [<0xffffffffc205a249>] in syscall at src/syscall.c:2582
#12 [<0xffffffffc205add8>] in run_local_syscall at src/syscall.c:2619
#13 [<0xffffffffc205b319>] in prep_syscalls at src/syscall.c:2639
#14 [<0xffffffffc20b7a92>] in sysenter_callwrapper at arch/x86/trap.c:932
kernel panic at kern/src/slab.c:658, from core 1: [German Accent]: OOM for a small slab growth!!!
Stack Backtrace on Core 1:
#01 [<0xffffffffc200aa6c>] in backtrace at src/kdebug.c:235
#02 [<0xffffffffc200a205>] in _panic at src/init.c:275
#03 [<0xffffffffc2053ef4>] in __kmem_alloc_from_slab at src/slab.c:658
#04 [<0xffffffffc20548da>] in kmem_cache_alloc at src/slab.c:696
#05 [<0xffffffffc2002497>] in arena_alloc at src/arena.c:839
#06 [<0xffffffffc2046675>] in kpages_alloc at src/page_alloc.c:80
#07 [<0xffffffffc200af5e>] in kmalloc at src/kmalloc.c:65
#08 [<0xffffffffc200b01f>] in kzmalloc at src/kmalloc.c:91
#09 [<0xffffffffc207fa69>] in mntralloc at drivers/dev/mnt.c:1120
#10 [<0xffffffffc207fb73>] in mntflushalloc at drivers/dev/mnt.c:1058
#11 [<0xffffffffc2080010>] in mountio at drivers/dev/mnt.c:854
#12 [<0xffffffffc2080105>] in mountrpc at drivers/dev/mnt.c:783
#13 [<0xffffffffc2080f3b>] in mntwalk at drivers/dev/mnt.c:475
#14 [<0xffffffffc2033bcb>] in walk at src/ns/chan.c:800
#15 [<0xffffffffc2034039>] in __namec_from at src/ns/chan.c:1138
#16 [<0xffffffffc2034c43>] in namec at src/ns/chan.c:1530
#17 [<0xffffffffc2041ddd>] in sysopenat at src/ns/sysfile.c:585
#18 [<0xffffffffc20592de>] in sys_openat at src/syscall.c:1826
#19 [<0xffffffffc205a249>] in syscall at src/syscall.c:2582
#20 [<0xffffffffc205add8>] in run_local_syscall at src/syscall.c:2619


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.