FYI, we noticed the following commit: https://git.kernel.org/pub/scm/linux/kernel/git/luto/linux.git x86/vmap_stack commit a611d6b7d4bdf3f57cfc792a45eb1ea5f4b776eb ("x86/mm/64: Enable vmapped stacks") on test machine: 2 threads qemu-system-x86_64 -enable-kvm -cpu Nehalem with 320M memory caused below changes: +----------------------------------------------------------------+------------+------------+ | | 8518e11969 | a611d6b7d4 | +----------------------------------------------------------------+------------+------------+ | boot_successes | 0 | 0 | | boot_failures | 16 | 17 | | BUG:KASAN:stack-out-of-bounds_in_setjmp_pre_handler_at_addr | 16 | | | BUG:KASAN:stack-out-of-bounds_in_longjmp_break_handler_at_addr | 16 | | | backtrace:init_kprobes | 16 | | | backtrace:kernel_init_freeable | 16 | | | double_fault:#[##]PREEMPT_SMP_KASAN | 0 | 17 | | RIP:pud_offset | 0 | 17 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 17 | +----------------------------------------------------------------+------------+------------+ [ 0.024009] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0 [ 0.027432] Freeing SMP alternatives memory: 16K (ffffffff8a11e000 - ffffffff8a122000) [ 0.027432] Freeing SMP alternatives memory: 16K (ffffffff8a11e000 - ffffffff8a122000) [ 0.031457] double fault: 0000 [#1] PREEMPT SMP KASAN [ 0.031457] double fault: 0000 [#1] PREEMPT SMP KASAN [ 0.032000] Modules linked in: [ 0.032000] Modules linked in: [ 0.032000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.7.0-rc4-00037-ga611d6b #1 [ 0.032000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.7.0-rc4-00037-ga611d6b #1 [ 0.032000] task: ffffffff89a13900 ti: ffffffff89a00000 task.ti: ffffffff89a00000 [ 0.032000] task: ffffffff89a13900 ti: ffffffff89a00000 task.ti: ffffffff89a00000 [ 0.032000] RIP: 0010:[] [ 0.032000] RIP: 0010:[] [] pud_offset+0x6/0x5e [] pud_offset+0x6/0x5e [ 0.032000] RSP: 0000:ffffc90000018000 EFLAGS: 00010002 [ 0.032000] RSP: 0000:ffffc90000018000 EFLAGS: 00010002 [ 0.032000] RAX: dffffc0000000000 RBX: 0000000000000003 RCX: ffffffff893430b0 [ 0.032000] RAX: dffffc0000000000 RBX: 0000000000000003 RCX: ffffffff893430b0 [ 0.032000] RDX: 1ffffffff13415ea RSI: fffff52000003039 RDI: ffffffff89a0af50 [ 0.032000] RDX: 1ffffffff13415ea RSI: fffff52000003039 RDI: ffffffff89a0af50 [ 0.032000] RBP: ffffc90000018008 R08: 0000000000030001 R09: 0000000000000001 [ 0.032000] RBP: ffffc90000018008 R08: 0000000000030001 R09: 0000000000000001 [ 0.032000] R10: ffffffff89a07cb0 R11: ffffffff8a01c2df R12: ffffffff89a0af50 [ 0.032000] R10: ffffffff89a07cb0 R11: ffffffff8a01c2df R12: ffffffff89a0af50 [ 0.032000] R13: fffff52000003039 R14: 0000000000000000 R15: dffffc0000000000 [ 0.032000] R13: fffff52000003039 R14: 0000000000000000 R15: dffffc0000000000 [ 0.032000] FS: 0000000000000000(0000) GS:ffff88000ee00000(0000) knlGS:0000000000000000 [ 0.032000] FS: 0000000000000000(0000) GS:ffff88000ee00000(0000) knlGS:0000000000000000 [ 0.032000] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.032000] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.032000] CR2: ffffc90000017ff8 CR3: 0000000009a0a000 CR4: 00000000000006b0 [ 0.032000] CR2: ffffc90000017ff8 CR3: 0000000009a0a000 CR4: 00000000000006b0 [ 0.032000] Stack: [ 0.032000] Stack: [ 0.032000] [ 0.032000] [ 0.032000] Call Trace: [ 0.032000] Call Trace: [ 0.032000] [ 0.032000] [ 0.032000] Code: [ 0.032000] Code: 00 00 fc fc ff ff df df 80 80 3c 3c 02 02 00 00 74 74 05 05 e8 e8 5e 5e 0d 0d 1f 1f 00 00 48 48 8b 8b 83 83 88 88 0a 0a 00 00 00 00 48 48 c1 c1 e8 e8 08 08 83 83 e0 e0 01 01 0f 0f b6 b6 c0 c0 5b 5b 41 41 5c 5c 5d 5d c3 c3 55 55 48 48 89 89 e5 e5 41 41 54 54 <53> <53> 49 49 89 89 fc fc 48 48 c1 c1 ee ee 1b 1b 48 48 89 89 f3 f3 81 81 e3 e3 f8 f8 0f 0f 00 00 00 00 48 48 89 89 fa fa 48 48 [ 0.032000] RIP [ 0.032000] RIP [] pud_offset+0x6/0x5e [] pud_offset+0x6/0x5e [ 0.032000] RSP [ 0.032000] RSP [ 0.032000] ---[ end trace f29da57a14fc8712 ]--- [ 0.032000] ---[ end trace f29da57a14fc8712 ]--- FYI, raw QEMU command line is: qemu-system-x86_64 -enable-kvm -cpu Nehalem -kernel /pkg/linux/x86_64-randconfig-b0-06221247+CONFIG_DEBUG_INFO_REDUCED/gcc-6/a611d6b7d4bdf3f57cfc792a45eb1ea5f4b776eb/vmlinuz-4.7.0-rc4-00037-ga611d6b -append 'root=/dev/ram0 user=lkp job=/lkp/scheduled/vm-intel12-yocto-x86_64-2/bisect_boot-1-yocto-minimal-x86_64.cgz-x86_64-randconfig-b0-06221247+CONFIG_DEBUG_INFO_REDUCED-a611d6b7d4bdf3f57cfc792a45eb1ea5f4b776eb-20160626-94002-kf25ng-0.yaml ARCH=x86_64 kconfig=x86_64-randconfig-b0-06221247+CONFIG_DEBUG_INFO_REDUCED branch=luto/x86/vmap_stack commit=a611d6b7d4bdf3f57cfc792a45eb1ea5f4b776eb BOOT_IMAGE=/pkg/linux/x86_64-randconfig-b0-06221247+CONFIG_DEBUG_INFO_REDUCED/gcc-6/a611d6b7d4bdf3f57cfc792a45eb1ea5f4b776eb/vmlinuz-4.7.0-rc4-00037-ga611d6b max_uptime=600 RESULT_ROOT=/result/boot/1/vm-intel12-yocto-x86_64/yocto-minimal-x86_64.cgz/x86_64-randconfig-b0-06221247+CONFIG_DEBUG_INFO_REDUCED/gcc-6/a611d6b7d4bdf3f57cfc792a45eb1ea5f4b776eb/0 LKP_SERVER=inn earlyprintk=ttyS0,115200 systemd.log_level=err debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal rw ip=::::vm-intel12-yocto-x86_64-2::dhcp drbd.minor_count=8' -initrd /fs/KVM/initrd-vm-intel12-yocto-x86_64-2 -m 320 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -drive file=/fs/KVM/disk0-vm-intel12-yocto-x86_64-2,media=disk,if=virtio -drive file=/fs/KVM/disk1-vm-intel12-yocto-x86_64-2,media=disk,if=virtio -pidfile /dev/shm/kboot/pid-vm-intel12-yocto-x86_64-2 -serial file:/dev/shm/kboot/serial-vm-intel12-yocto-x86_64-2 -daemonize -display none -monitor null Thanks, Xiaolong