hi, Arvind Yadav, we know this commit is quite old, but it shows persistent low rate issue and parent keeps clean even when we run both this commit and parent up to ~300 times. the config to build both kernel is a randconfig as in https://download.01.org/0day-ci/archive/20230913/202309132239.70437559-oliver.sang@xxxxxxxxx c85d00d4fd8b98ea d62c43a953ce02d54521ec06217 ---------------- --------------------------- fail:runs %reproduction fail:runs | | | :300 6% 17:312 dmesg.BUG_mock_fence(Tainted:G_T):Objects_remaining_in_mock_fence_on__kmem_cache_shutdown() :300 11% 33:312 dmesg.EIP:kmem_cache_destroy :300 11% 33:312 dmesg.WARNING:at_mm/slab_common.c:#kmem_cache_destroy at the same time, as in below formal report mentioned, we still observed similar issue on latest linus/master and linux-next/master, so we just send out this report FYI. Hello, kernel test robot noticed "WARNING:at_mm/slab_common.c:#kmem_cache_destroy" on: commit: d62c43a953ce02d54521ec06217d0c2ed6d489af ("dma-buf: Enable signaling on fence for selftests") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master [test failed on linus/master 0bb80ecc33a8fb5a682236443c1e740d5c917d1d] [test failed on linux-next/master 3c13c772fc233a10342c8e1605ff0855dfdf0c89] in testcase: boot compiler: gcc-12 test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 4G (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@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-lkp/202309132239.70437559-oliver.sang@xxxxxxxxx [ 21.601153][ T1] ------------[ cut here ]------------ [ 21.693224][ T1] kmem_cache_destroy mock_fence: Slab cache still has objects when called from dma_fence_chain (drivers/dma-buf/st-dma-fence-chain.c:709) [ 21.693275][ T1] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:478 kmem_cache_destroy (mm/slab_common.c:478) [ 21.697039][ T1] Modules linked in: [ 21.697859][ T1] CPU: 0 PID: 1 Comm: swapper Tainted: G T 6.0.0-rc2-00744-gd62c43a953ce #1 26be6099e9dfaf1dc1fa091a1f5a61f95afa9121 [ 21.700290][ T1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 [ 21.702175][ T1] EIP: kmem_cache_destroy (mm/slab_common.c:478) [ 21.707576][ T1] Code: 00 ff 4b 2c 0f 85 b2 00 00 00 89 d8 e8 ea 4a 02 00 85 c0 74 1f ff 75 04 ff 73 40 68 6c ff 96 d7 68 7d 44 09 d8 e8 40 c8 da 00 <0f> 0b 83 c4 10 e9 88 00 00 00 8d 73 44 89 f0 e8 8a 8e 2e 00 84 c0 All code ======== 0: 00 ff add %bh,%bh 2: 4b 2c 0f rex.WXB sub $0xf,%al 5: 85 b2 00 00 00 89 test %esi,-0x77000000(%rdx) b: d8 e8 fsubr %st(0),%st d: ea (bad) e: 4a 02 00 rex.WX add (%rax),%al 11: 85 c0 test %eax,%eax 13: 74 1f je 0x34 15: ff 75 04 push 0x4(%rbp) 18: ff 73 40 push 0x40(%rbx) 1b: 68 6c ff 96 d7 push $0xffffffffd796ff6c 20: 68 7d 44 09 d8 push $0xffffffffd809447d 25: e8 40 c8 da 00 call 0xdac86a 2a:* 0f 0b ud2 <-- trapping instruction 2c: 83 c4 10 add $0x10,%esp 2f: e9 88 00 00 00 jmp 0xbc 34: 8d 73 44 lea 0x44(%rbx),%esi 37: 89 f0 mov %esi,%eax 39: e8 8a 8e 2e 00 call 0x2e8ec8 3e: 84 c0 test %al,%al Code starting with the faulting instruction =========================================== 0: 0f 0b ud2 2: 83 c4 10 add $0x10,%esp 5: e9 88 00 00 00 jmp 0x92 a: 8d 73 44 lea 0x44(%rbx),%esi d: 89 f0 mov %esi,%eax f: e8 8a 8e 2e 00 call 0x2e8e9e 14: 84 c0 test %al,%al [ 21.711048][ T1] EAX: 00000066 EBX: ee62b680 ECX: 00000001 EDX: 80000001 [ 21.712412][ T1] ESI: d87beb98 EDI: ffffffff EBP: c128dee8 ESP: c128decc [ 21.713723][ T1] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010292 [ 21.715192][ T1] CR0: 80050033 CR2: b7d07070 CR3: 189fe000 CR4: 00040690 [ 21.716533][ T1] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 21.717859][ T1] DR6: fffe0ff0 DR7: 00000400 [ 21.718792][ T1] Call Trace: [ 21.719488][ T1] ? dma_fence_chain (drivers/dma-buf/st-dma-fence-chain.c:709) [ 21.720419][ T1] dma_fence_chain (drivers/dma-buf/st-dma-fence-chain.c:709) [ 21.721327][ T1] st_init (drivers/dma-buf/selftest.c:141 drivers/dma-buf/selftest.c:155) [ 21.722117][ T1] ? udmabuf_dev_init (drivers/dma-buf/selftest.c:154) [ 21.723147][ T1] do_one_initcall (init/main.c:1296) [ 21.724108][ T1] do_initcalls (init/main.c:1368 init/main.c:1385) [ 21.725029][ T1] kernel_init_freeable (init/main.c:1615) [ 21.726030][ T1] ? rest_init (init/main.c:1492) [ 21.726907][ T1] kernel_init (init/main.c:1502) [ 21.727732][ T1] ret_from_fork (arch/x86/entry/entry_32.S:770) [ 21.728608][ T1] irq event stamp: 1964001 [ 21.729500][ T1] hardirqs last enabled at (1964011): __up_console_sem (arch/x86/include/asm/irqflags.h:29 (discriminator 1) arch/x86/include/asm/irqflags.h:70 (discriminator 1) arch/x86/include/asm/irqflags.h:130 (discriminator 1) kernel/printk/printk.c:264 (discriminator 1)) [ 21.731230][ T1] hardirqs last disabled at (1964020): __up_console_sem (kernel/printk/printk.c:262 (discriminator 1)) [ 21.735324][ T1] softirqs last enabled at (1963746): __do_softirq (arch/x86/include/asm/preempt.h:27 kernel/softirq.c:415 kernel/softirq.c:600) [ 21.736992][ T1] softirqs last disabled at (1963735): do_softirq_own_stack (arch/x86/kernel/irq_32.c:60 arch/x86/kernel/irq_32.c:150) [ 21.738743][ T1] ---[ end trace 0000000000000000 ]--- [ 21.739776][ T1] dma-buf: Running dma_fence_unwrap The kernel config and materials to reproduce are available at: https://download.01.org/0day-ci/archive/20230913/202309132239.70437559-oliver.sang@xxxxxxxxx -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki