FYI, we noticed the following commit (built with gcc-7): commit: 0830cf62f5290b2f878faacc2b6f32e77bc2ea12 ("x86/unwind: Add hardcoded ORC entry for NULL") https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable-rc.git linux-5.0.y in testcase: trinity with following parameters: runtime: 300s 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 2G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +------------------------------------+------------+------------+ | | 0312f3032e | 0830cf62f5 | +------------------------------------+------------+------------+ | boot_successes | 66 | 52 | | boot_failures | 0 | 14 | | BUG:KASAN:stack-out-of-bounds_in_u | 0 | 14 | | RIP:__x86_indirect_thunk_rdx | 0 | 14 | +------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <rong.a.chen(a)intel.com&gt; [ 176.470970] BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x1361/0x1b20 [ 176.473005] Read of size 8 at addr ffff88805723f878 by task trinity-main/605 [ 176.474776] [ 176.475424] CPU: 1 PID: 605 Comm: trinity-main Not tainted 5.0.4-00048-g0830cf6 #1 [ 176.477513] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 176.479754] Call Trace: [ 176.480590] <IRQ> [ 176.481344] dump_stack+0x5b/0x8b [ 176.482358] ? unwind_next_frame+0x1361/0x1b20 [ 176.483598] print_address_description+0x6a/0x290 [ 176.484893] ? unwind_next_frame+0x1361/0x1b20 [ 176.486126] ? unwind_next_frame+0x1361/0x1b20 [ 176.487370] kasan_report+0x139/0x199 [ 176.488450] ? unwind_next_frame+0x1361/0x1b20 [ 176.489690] unwind_next_frame+0x1361/0x1b20 [ 176.490893] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.492288] ? unwind_get_return_address_ptr+0xb0/0xb0 [ 176.493662] ? rcu_dynticks_curr_cpu_in_eqs+0x54/0xb0 [ 176.495016] ? rcu_is_watching+0xc/0x20 [ 176.496131] ? rcu_is_watching+0xc/0x20 [ 176.497251] ? kernel_text_address+0x68/0x90 [ 176.498454] __save_stack_trace+0x73/0xd0 [ 176.499607] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.500995] save_stack+0x32/0xb0 [ 176.502003] ? __kasan_slab_free+0x130/0x180 [ 176.503204] ? kfree+0xaa/0x1e0 [ 176.504176] ? rcu_process_callbacks+0x4b5/0xd00 [ 176.505467] ? __do_softirq+0x1bc/0x6d9 [ 176.506590] ? irq_exit+0x10f/0x130 [ 176.507644] ? smp_apic_timer_interrupt+0x176/0x400 [ 176.508994] ? apic_timer_interrupt+0xf/0x20 [ 176.510220] ? __x86_indirect_thunk_rcx+0x20/0x20 [ 176.511515] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.512935] ? check_preempt_wakeup+0x2b4/0x690 [ 176.514233] ? probe_sched_switch+0x30/0x30 [ 176.515442] ? tracing_record_taskinfo_skip+0x56/0x70 [ 176.516824] ? tracing_record_taskinfo+0x14/0x1a0 [ 176.518156] ? ttwu_do_wakeup+0x3a1/0x530 [ 176.519304] ? _raw_spin_unlock_irqrestore+0x18/0x30 [ 176.520561] ? try_to_wake_up+0xc5/0x11e0 [ 176.521635] ? __migrate_task+0x140/0x140 [ 176.522705] ? _raw_spin_lock_irqsave+0x84/0xd0 [ 176.523957] ? _raw_spin_lock_irq+0xd0/0xd0 [ 176.525146] __kasan_slab_free+0x130/0x180 [ 176.526311] ? rcu_process_callbacks+0x4b5/0xd00 [ 176.527578] kfree+0xaa/0x1e0 [ 176.528515] rcu_process_callbacks+0x4b5/0xd00 [ 176.529708] ? rcu_read_unlock_special+0xf0/0xf0 [ 176.530908] ? sched_clock_cpu+0x31/0x1e0 [ 176.531934] __do_softirq+0x1bc/0x6d9 [ 176.532851] irq_exit+0x10f/0x130 [ 176.533709] smp_apic_timer_interrupt+0x176/0x400 [ 176.534800] apic_timer_interrupt+0xf/0x20 [ 176.535789] </IRQ> [ 176.536434] RIP: 0010:__x86_indirect_thunk_rdx+0x0/0x20 [ 176.537618] Code: 84 00 00 00 00 00 0f 1f 40 00 e8 07 00 00 00 f3 90 0f ae e8 eb f9 48 89 0c 24 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <e8> 07 00 00 00 f3 90 0f ae e8 eb f9 48 89 14 24 c3 66 66 2e 0f 1f [ 176.541507] RSP: 0018:ffff88805723f7f0 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13 [ 176.543287] RAX: 0000000000000005 RBX: ffff88805723f8c8 RCX: 0000000000000000 [ 176.545047] RDX: ffffffff968efe39 RSI: 0000000000000001 RDI: 0000000000000001 [ 176.546782] RBP: 1ffff1100ae47f06 R08: ffffffff9d146598 R09: ffffffff9d14659c [ 176.548526] R10: 00000000000ebfb5 R11: ffff88805723f8fd R12: 0000000000000001 [ 176.550261] R13: ffff88805723f910 R14: ffff88805723f900 R15: ffff88805723f918 [ 176.554447] ? unwind_next_frame+0x8b9/0x1b20 [ 176.555638] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.556907] RIP: 5bd3e400:0x2 [ 176.557788] Code: Bad RIP value. [ 176.558712] RSP: 5723f940:ffff88805723f950 EFLAGS: 1010000000000 ORIG_RAX: 0000000000000000 [ 176.560829] RAX: ffff88805723f8d0 RBX: ffff88805723f8d8 RCX: ffff88805723ff58 [ 176.562513] RDX: 0000000000000001 RSI: ffff888057238000 RDI: ffff888057240000 [ 176.564191] RBP: ffffffff9cbbef86 R08: ffffffff968ef580 R09: ffffffff9b9d951c [ 176.565852] R10: 0000000041b58ab3 R11: ffffffff96a0e86e R12: ffff88805723f8fd [ 176.567548] R13: ffffffff9cbbef82 R14: ffff88805723f8fd R15: ffff88805723ff58 [ 176.569293] ? __kernel_text_address+0xe/0x30 [ 176.570492] ? unwind_get_return_address_ptr+0xb0/0xb0 [ 176.571848] ? __save_stack_trace+0x73/0xd0 [ 176.573048] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.574368] ? save_stack+0x32/0xb0 [ 176.575362] ? __kasan_kmalloc+0xa0/0xd0 [ 176.576631] ? kmem_cache_alloc+0xb7/0x1b0 [ 176.577739] ? anon_vma_fork+0xcf/0x5b0 [ 176.578800] ? copy_process+0x4f25/0x5a90 [ 176.580208] ? _do_fork+0x13f/0x840 [ 176.581224] ? do_syscall_64+0x96/0x8fb [ 176.582300] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.583654] ? kmem_cache_alloc+0xb7/0x1b0 [ 176.584804] ? vm_area_dup+0x1e/0x180 [ 176.585884] ? copy_process+0x4b1b/0x5a90 [ 176.587146] ? _do_fork+0x13f/0x840 [ 176.588159] ? do_syscall_64+0x96/0x8fb [ 176.589221] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 176.590549] ? copy_page_range+0xe56/0x1ad0 [ 176.591711] ? kasan_unpoison_shadow+0x30/0x40 [ 176.592933] ? __kasan_kmalloc+0xa0/0xd0 [ 176.594114] ? kasan_unpoison_shadow+0x30/0x40 [ 176.595168] ? __kasan_kmalloc+0xa0/0xd0 [ 176.596302] ? anon_vma_fork+0xcf/0x5b0 [ 176.597241] ? kmem_cache_alloc+0xb7/0x1b0 [ 176.598225] ? anon_vma_fork+0xcf/0x5b0 [ 176.599168] ? copy_process+0x4f25/0x5a90 [ 176.600255] ? __cleanup_sighand+0x40/0x40 [ 176.601240] ? __might_fault+0x87/0xb0 To reproduce: # build kernel cd linux cp config-5.0.4-00048-g0830cf6 .config make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 olddefconfig make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 prepare make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 modules_prepare make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 SHELL=/bin/bash make HOSTCC=gcc-7 CC=gcc-7 ARCH=x86_64 bzImage git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email Thanks, Rong Chen