Greeting, FYI, we noticed the following commit (built with gcc-9): commit: e242a269fa4b7aee0b157ce5b1d7d12179fc3c44 ("[PATCH 5/6] tlb: mmu_gather: Introduce tlb_gather_mmu_fullmm()") url: https://github.com/0day-ci/linux/commits/Will-Deacon/tlb-Fix-access-and-soft-dirty-bit-management/20201120-223809 base: https://git.kernel.org/cgit/linux/kernel/git/arm64/linux.git for-next/core in testcase: locktorture version: with following parameters: runtime: 300s test: default test-description: This torture test consists of creating a number of kernel threads which acquire the lock and hold it for specific amount of time, thus simulating different critical region behaviors. test-url: https://www.kernel.org/doc/Documentation/locking/locktorture.txt on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +----------------------------------------------------------------------------+------------+------------+ | | 8303731515 | e242a269fa | +----------------------------------------------------------------------------+------------+------------+ | boot_successes | 4 | 0 | | boot_failures | 0 | 28 | | WARNING:at_mm/mmu_gather.c:#tlb_gather_mmu | 0 | 28 | | RIP:tlb_gather_mmu | 0 | 28 | +----------------------------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot [ 14.182822] WARNING: CPU: 0 PID: 1 at mm/mmu_gather.c:293 tlb_gather_mmu+0x40/0x99 [ 14.184719] Modules linked in: [ 14.185638] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc3-00061-ge242a269fa4b #2 [ 14.186126] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 14.188226] RIP: 0010:tlb_gather_mmu+0x40/0x99 [ 14.189429] Code: 3c 25 00 91 01 00 4c 8b 07 41 0f ba e0 1d 73 15 f6 87 ab 08 00 00 08 b8 00 00 00 c0 bf 00 e0 ff ff 48 0f 44 c7 48 39 c8 73 02 <0f> 0b 48 ff c1 48 89 33 48 89 df 48 09 d1 8a 53 20 48 c7 43 30 00 [ 14.189467] RSP: 0000:ffff8881002b3a30 EFLAGS: 00010207 [ 14.190751] RAX: 00007ffffffff000 RBX: ffff8881002b3a40 RCX: ffff888000000000 [ 14.192368] RDX: ffff880000000000 RSI: ffff8881002a0640 RDI: ffff8881002a8000 [ 14.192790] RBP: ffff8881002a0640 R08: 0000000000004000 R09: ffff8881002a8ca8 [ 14.194615] R10: ffff8881002b3b58 R11: 0000000000000000 R12: ffff8881002a07a0 [ 14.196127] R13: ffff888100835000 R14: 0000000000000000 R15: 0000000000000000 [ 14.197900] FS: 0000000000000000(0000) GS:ffff888237a00000(0000) knlGS:0000000000000000 [ 14.199456] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 14.200897] CR2: 0000000000000000 CR3: 0000000002628000 CR4: 00000000000406b0 [ 14.202629] Call Trace: [ 14.202838] free_ldt_pgtables+0x3c/0x85 [ 14.204130] ? hlock_class+0x1a/0x5d [ 14.205173] ? kvm_clock_read+0x14/0x1c [ 14.206122] ? kvm_sched_clock_read+0x5/0xd [ 14.207226] ? paravirt_sched_clock+0x11/0x14 [ 14.208351] ? sched_clock_local+0xc/0x75 [ 14.209454] ? sched_clock_cpu+0x9f/0xaf [ 14.210435] ? hlock_class+0x1a/0x5d [ 14.211370] exit_mmap+0xb9/0x16b [ 14.212349] ? __mutex_unlock_slowpath+0x43/0x20d [ 14.212794] __mmput+0x37/0xbf [ 14.213596] dma_resv_lockdep+0x240/0x265 [ 14.214699] ? sched_clock_local+0xc/0x75 [ 14.215866] ? dma_resv_lockdep+0x124/0x265 [ 14.216125] ? hlock_class+0x1a/0x5d [ 14.217141] ? dma_resv_lockdep+0x186/0x265 [ 14.218305] ? dma_buf_init+0xca/0xca [ 14.219361] do_one_initcall+0xa2/0x1c8 [ 14.219461] kernel_init_freeable+0x203/0x248 [ 14.220614] ? rest_init+0xcd/0xcd [ 14.221619] kernel_init+0xa/0xfa [ 14.222657] ret_from_fork+0x1f/0x30 [ 14.222793] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc3-00061-ge242a269fa4b #2 [ 14.224914] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 14.226096] Call Trace: [ 14.226096] dump_stack+0x57/0x6a [ 14.226096] __warn+0xbb/0xe7 [ 14.226096] ? tlb_gather_mmu+0x40/0x99 [ 14.226096] report_bug+0x96/0xd6 [ 14.226096] handle_bug+0x3c/0x5d [ 14.226096] exc_invalid_op+0x14/0x61 [ 14.226096] asm_exc_invalid_op+0x12/0x20 [ 14.226096] RIP: 0010:tlb_gather_mmu+0x40/0x99 [ 14.226096] Code: 3c 25 00 91 01 00 4c 8b 07 41 0f ba e0 1d 73 15 f6 87 ab 08 00 00 08 b8 00 00 00 c0 bf 00 e0 ff ff 48 0f 44 c7 48 39 c8 73 02 <0f> 0b 48 ff c1 48 89 33 48 89 df 48 09 d1 8a 53 20 48 c7 43 30 00 [ 14.226096] RSP: 0000:ffff8881002b3a30 EFLAGS: 00010207 [ 14.226096] RAX: 00007ffffffff000 RBX: ffff8881002b3a40 RCX: ffff888000000000 [ 14.226096] RDX: ffff880000000000 RSI: ffff8881002a0640 RDI: ffff8881002a8000 [ 14.226096] RBP: ffff8881002a0640 R08: 0000000000004000 R09: ffff8881002a8ca8 [ 14.226096] R10: ffff8881002b3b58 R11: 0000000000000000 R12: ffff8881002a07a0 [ 14.226096] R13: ffff888100835000 R14: 0000000000000000 R15: 0000000000000000 [ 14.226096] free_ldt_pgtables+0x3c/0x85 [ 14.226096] ? hlock_class+0x1a/0x5d [ 14.226096] ? kvm_clock_read+0x14/0x1c [ 14.226096] ? kvm_sched_clock_read+0x5/0xd [ 14.226096] ? paravirt_sched_clock+0x11/0x14 [ 14.226096] ? sched_clock_local+0xc/0x75 [ 14.226096] ? sched_clock_cpu+0x9f/0xaf [ 14.226096] ? hlock_class+0x1a/0x5d [ 14.226096] exit_mmap+0xb9/0x16b [ 14.226096] ? __mutex_unlock_slowpath+0x43/0x20d [ 14.226096] __mmput+0x37/0xbf [ 14.226096] dma_resv_lockdep+0x240/0x265 [ 14.226096] ? sched_clock_local+0xc/0x75 [ 14.226096] ? dma_resv_lockdep+0x124/0x265 [ 14.226096] ? hlock_class+0x1a/0x5d [ 14.226096] ? dma_resv_lockdep+0x186/0x265 [ 14.226096] ? dma_buf_init+0xca/0xca [ 14.226096] do_one_initcall+0xa2/0x1c8 [ 14.226096] kernel_init_freeable+0x203/0x248 [ 14.226096] ? rest_init+0xcd/0xcd [ 14.226096] kernel_init+0xa/0xfa [ 14.226096] ret_from_fork+0x1f/0x30 [ 14.226125] ---[ end trace b1a6193bbc625c98 ]--- To reproduce: # build kernel cd linux cp config-5.10.0-rc3-00061-ge242a269fa4b .config make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage modules make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 INSTALL_MOD_PATH= modules_install cd find lib/ | cpio -o -H newc --quiet | gzip > modules.cgz git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k -m modules.cgz job-script # job-script is attached in this email Thanks, Oliver Sang