[linux-next:master] [slub] d543c8fb9c: BUG_filp(Not_tainted):Bulk_free_expected#objects_but_found

[linux-next:master] [slub] d543c8fb9c: BUG_filp(Not_tainted):Bulk_free_expected#objects_but_found

[kernel test robot]

hi, Jann Horn,

we reported "WARNING:possible_circular_locking_dependency_detected"
issue upon v3 of this patch in
https://lore.kernel.org/all/202407291014.2ead1e72-oliver.sang@intel.com/
several days ago.

at that time, you said that real issue should be something like
"BUG filp (Not tainted): Bulk free expected 1 objects but found 2"
and you will send a fix.

now we noticed this patch in in linux-next/master, but not sure the version.

we found there are still similar issues so just send report to you FYI.



Hello,

kernel test robot noticed "BUG_filp(Not_tainted):Bulk_free_expected#objects_but_found" on:

commit: d543c8fb9c4caa95cd2799b9d3b6f6354140f4f4 ("slub: introduce CONFIG_SLUB_RCU_DEBUG")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master

[test failed on linux-next/master cd19ac2f903276b820f5d0d89de0c896c27036ed]

in testcase: rcutorture
version: 
with following parameters:

	runtime: 300s
	test: cpuhotplug
	torture_type: srcud



compiler: gcc-13
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

(please refer to attached dmesg/kmsg for entire log/backtrace)



If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202407311019.5ea52390-lkp@intel.com


[  243.911590][    T0] masked ExtINT on CPU#1
[  244.087218][    T9] smpboot: CPU 1 is now offline
[  244.154988][  T435] smpboot: Booting Node 0 Processor 1 APIC 0x1
[  244.155553][    T0] masked ExtINT on CPU#1
[  244.226610][    C1] =============================================================================
[  244.227574][    C1] BUG filp (Not tainted): Bulk free expected 1 objects but found 2
[  244.227574][    C1]
[  244.228097][    C1] -----------------------------------------------------------------------------
[  244.228097][    C1]
[  244.228665][    C1] Slab 0xffffea0005dac500 objects=23 used=23 fp=0x0000000000000000 flags=0x8000000000000040(head|zone=2)
[  244.229241][    C1] CPU: 1 UID: 0 PID: 22 Comm: cpuhp/1 Not tainted 6.10.0-12959-gd543c8fb9c4c #1
[  244.229725][    C1] Call Trace:
[  244.229909][    C1]  <IRQ>
[ 244.230069][ C1] dump_stack_lvl (kbuild/src/consumer/lib/dump_stack.c:122) 
[ 244.230337][ C1] slab_err (kbuild/src/consumer/mm/slub.c:1149) 
[ 244.230606][ C1] ? check_object (kbuild/src/consumer/mm/slub.c:1293 kbuild/src/consumer/mm/slub.c:1391) 
[ 244.230925][ C1] free_debug_processing (kbuild/src/consumer/mm/slub.c:3378) 


The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20240731/202407311019.5ea52390-lkp@intel.com



-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [linux-next:master] [slub] d543c8fb9c: BUG_filp(Not_tainted):Bulk_free_expected#objects_but_found

[Jann Horn]

Hi!

On Wed, Jul 31, 2024 at 7:27 AM kernel test robot <oliver.sang@intel.com> wrote:
> hi, Jann Horn,
>
> we reported "WARNING:possible_circular_locking_dependency_detected"
> issue upon v3 of this patch in
> https://lore.kernel.org/all/202407291014.2ead1e72-oliver.sang@intel.com/
> several days ago.
>
> at that time, you said that real issue should be something like
> "BUG filp (Not tainted): Bulk free expected 1 objects but found 2"
> and you will send a fix.
>
> now we noticed this patch in in linux-next/master, but not sure the version.
>
> we found there are still similar issues so just send report to you FYI.

Right, that's still v2 of the patch - you can tell from the "Link:
https://lkml.kernel.org/r/20240724-kasan-tsbrcu-v2-2-45f898064468@google.com"
line in the commit message, which contains "v2" and links to an email
with subject "[PATCH v2 2/2] slub: Introduce CONFIG_SLUB_RCU_DEBUG".

And yeah, that seems like the same issue that I fixed in v4 of the
patch (https://lore.kernel.org/all/20240729-kasan-tsbrcu-v4-2-57ec85ef80c6@google.com/).
v5 is now in the mm tree, so I think once the next version of
linux-next is built, the issue should go away.

Have a nice day,
Jann