FYI, we noticed the following commit: https://github.com/0day-ci/linux Manjeet-Pawar/arm64-swiotlb-Enable-only-when-Input-size-through-command-line/20160623-205508 commit 60edbdb955e718ac4ea403f13edc30d4dc31fbeb ("arm64:swiotlb:Enable only when Input size through command line") on test machine: vm-lkp-wsx03-4G: 2 threads qemu-system-x86_64 -enable-kvm -cpu host with 4G memory caused below changes: +----------------------------------------------------------------------------+----------+------------+ | | v4.7-rc4 | 60edbdb955 | +----------------------------------------------------------------------------+----------+------------+ | boot_successes | 5972 | 19 | | boot_failures | 87 | 20 | | Initramfs_unpacking_failed | 1 | | | Kernel_panic-not_syncing:VFS:Unable_to_mount_root_fs_on_unknown-block(#,#) | 1 | | | backtrace:prepare_namespace | 1 | | | backtrace:kernel_init_freeable | 14 | 4 | | kernel_BUG_at_fs/btrfs/ctree.c | 1 | | | invalid_opcode:#[##]SMP | 1 | | | RIP:btrfs_set_item_key_safe[btrfs] | 1 | | | Kernel_panic-not_syncing:Fatal_exception | 1 | 1 | | backtrace:vfs_write | 24 | | | backtrace:SyS_write | 23 | | | WARNING:at_drivers/gpu/drm/i915/intel_display.c:#intel_modeset_init[i915] | 5 | | | backtrace:intel_modeset_init | 5 | | | backtrace:warn_slowpath_fmt | 5 | | | backtrace:__pci_register_driver | 5 | | | backtrace:drm_pci_init | 5 | | | backtrace:i915_init | 5 | | | backtrace:do_init_module | 25 | | | backtrace:load_module | 24 | | | backtrace:SYSC_finit_module | 24 | | | backtrace:SyS_finit_module | 24 | | | drm:fw_domains_get[i915]] | 20 | | | drm:__gen6_gt_wait_for_thread_c0[i915]] | 20 | | | BUG:sleeping_function_called_from_invalid_context_at_kernel/irq/manage.c | 20 | | | backtrace:snb_uncore_imc_init_box | 20 | | | backtrace:register_console | 19 | | | backtrace:init_netconsole | 20 | | | backtrace:netpoll_poll_dev | 1 | | | invoked_oom-killer:gfp_mask=0x | 39 | | | Mem-Info | 39 | | | Out_of_memory:Kill_process | 26 | | | backtrace:_do_fork | 9 | | | backtrace:SyS_clone | 8 | | | backtrace:do_execveat_common | 2 | | | backtrace:SyS_execve | 2 | | | backtrace:kimage_load_segment | 3 | | | backtrace:SyS_kexec_load | 3 | | | WARNING:at_mm/early_ioremap.c:#__early_ioremap | 1 | | | backtrace:acpi_initialize_tables | 1 | | | backtrace:acpi_table_init | 1 | | | backtrace:acpi_boot_table_init | 1 | | | WARNING:at_arch/x86/events/intel/core.c:#intel_pmu_handle_irq | 6 | | | backtrace:pgd_alloc | 1 | | | backtrace:mm_init | 1 | | | WARNING:at_fs/xfs/xfs_file.c:#xfs_file_read_iter | 1 | | | WARNING:at_fs/xfs/xfs_file.c:#xfs_file_dio_aio_write | 2 | | | backtrace:vfs_read | 3 | | | backtrace:SyS_read | 3 | | | backtrace:SyS_pwrite64 | 1 | | | backtrace:vm_mmap_pgoff | 2 | | | backtrace:SyS_mmap_pgoff | 2 | | | backtrace:SyS_mmap | 2 | | | BUG:kernel_test_crashed | 4 | | | BUG:kernel_test_hang | 7 | | | Kernel_panic-not_syncing:Out_of_memory_and_no_killable_processes | 13 | | | backtrace:populate_rootfs | 13 | | | BUG:unable_to_handle_kernel | 0 | 20 | | Oops | 0 | 20 | | RIP:__memcpy | 0 | 15 | | Kernel_panic-not_syncing:Fatal_exception_in_interrupt | 0 | 19 | | backtrace:cpu_startup_entry | 0 | 4 | | backtrace:ip_auto_config | 0 | 4 | | RIP:clear_page | 0 | 1 | | backtrace:SYSC_newlstat | 0 | 1 | | backtrace:SyS_newlstat | 0 | 1 | | backtrace:nfs_create_rpc_client | 0 | 2 | | backtrace:nfs4_init_client | 0 | 2 | | backtrace:do_mount | 0 | 2 | | backtrace:SyS_mount | 0 | 2 | | backtrace:xs_tcp_setup_socket | 0 | 1 | | backtrace:addrconf_dad_work | 0 | 1 | | RIP:memcpy_orig | 0 | 4 | +----------------------------------------------------------------------------+----------+------------+ [ 5.237245] input: ImExPS/2 BYD TouchPad as /devices/platform/i8042/serio1/input/input3 [ 6.617721] e1000: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX [ 6.620309] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 6.624262] BUG: unable to handle kernel paging request at ffff8800bffe0000 [ 6.625923] IP: [<ffffffff81440f12>] __memcpy+0x12/0x20 [ 6.627251] PGD 23c0067 PUD 13ffff067 PMD 13fffe067 PTE 0 [ 6.628834] Oops: 0002 [#1] SMP [ 6.629816] Modules linked in: [ 6.630854] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.7.0-rc4-00001-g60edbdb #1 [ 6.632902] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 6.635146] task: ffffffff81e0d500 ti: ffffffff81e00000 task.ti: ffffffff81e00000 [ 6.637167] RIP: 0010:[<ffffffff81440f12>] [<ffffffff81440f12>] __memcpy+0x12/0x20 [ 6.639320] RSP: 0018:ffff88013fc03990 EFLAGS: 00010202 [ 6.640576] RAX: ffff8800bffe0000 RBX: 00000000bffe0000 RCX: 000000000000000b [ 6.642071] RDX: 0000000000000002 RSI: ffff8801328f3802 RDI: ffff8800bffe0000 [ 6.643567] RBP: ffff88013fc039f8 R08: 00000001328f3802 R09: 0000160000000000 [ 6.645069] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 6.646559] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000200000 [ 6.648066] FS: 0000000000000000(0000) GS:ffff88013fc00000(0000) knlGS:0000000000000000 [ 6.650171] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6.651483] CR2: ffff8800bffe0000 CR3: 0000000001e06000 CR4: 00000000000006f0 [ 6.652977] Stack: [ 6.653798] ffffffff8145b88e 0000000100000000 00000001328f3802 0000000000000001 [ 6.656135] 0000000000000202 ffff88013a5af0a0 000000000000005a 000000000017ffc0 [ 6.658459] 00000001328f3802 ffff88013a5af0a0 000000000000005a ffffc9000075e000 [ 6.660777] Call Trace: [ 6.661653] <IRQ> [ 6.661991] [<ffffffff8145b88e>] ? swiotlb_tbl_map_single+0x26e/0x2c0 [ 6.664004] [<ffffffff8145beb2>] swiotlb_map_page+0x82/0x1c0 [ 6.665325] [<ffffffff8161de31>] e1000_xmit_frame+0x351/0x1110 [ 6.666668] [<ffffffff817dbcd1>] dev_hard_start_xmit+0xa1/0x220 [ 6.668023] [<ffffffff81801c3c>] sch_direct_xmit+0xdc/0x1b0 [ 6.669320] [<ffffffff817dc381>] __dev_queue_xmit+0x3e1/0x640 [ 6.670639] [<ffffffff817e95d7>] ? __neigh_create+0x447/0x5a0 [ 6.671965] [<ffffffff817dc5f0>] dev_queue_xmit+0x10/0x20 [ 6.673242] [<ffffffff817e5f88>] neigh_resolve_output+0x118/0x1c0 [ 6.674622] [<ffffffff8188e2f8>] ip6_finish_output2+0x188/0x4a0 [ 6.675978] [<ffffffff813c6fea>] ? selinux_ipv6_postroute+0x1a/0x20 [ 6.677390] [<ffffffff8188f956>] ip6_finish_output+0xa6/0x100 [ 6.678712] [<ffffffff8188f9f8>] ip6_output+0x48/0xf0 [ 6.679956] [<ffffffff8188f8b0>] ? ip6_fragment+0x9c0/0x9c0 [ 6.681259] [<ffffffff818b1a70>] NF_HOOK_THRESH+0x30/0xa0 [ 6.682687] [<ffffffff8189f271>] ? icmp6_dst_alloc+0x121/0x170 [ 6.684060] [<ffffffff818b1c44>] mld_sendpack+0x164/0x210 [ 6.685335] [<ffffffff818b2eb3>] mld_ifc_timer_expire+0x193/0x2a0 [ 6.686699] [<ffffffff818b2d20>] ? mld_dad_timer_expire+0x60/0x60 [ 6.688072] [<ffffffff810ea575>] call_timer_fn+0x35/0x140 [ 6.689344] [<ffffffff818b2d20>] ? mld_dad_timer_expire+0x60/0x60 [ 6.690705] [<ffffffff810eb54d>] run_timer_softirq+0x23d/0x2e0 [ 6.692045] [<ffffffff8191a35f>] __do_softirq+0xff/0x2d2 [ 6.693309] [<ffffffff81083468>] irq_exit+0xe8/0xf0 [ 6.694531] [<ffffffff8191a152>] smp_apic_timer_interrupt+0x42/0x50 [ 6.695914] [<ffffffff8191829c>] apic_timer_interrupt+0x8c/0xa0 [ 6.697264] <EOI> [ 6.697596] [<ffffffff8105ff26>] ? native_safe_halt+0x6/0x10 [ 6.699487] [<ffffffff8103785e>] default_idle+0x1e/0xf0 [ 6.700731] [<ffffffff8103803f>] arch_cpu_idle+0xf/0x20 [ 6.701987] [<ffffffff810c2203>] default_idle_call+0x33/0x40 [ 6.703304] [<ffffffff810c24c3>] cpu_startup_entry+0x2b3/0x310 [ 6.704644] [<ffffffff8190a445>] rest_init+0x85/0x90 [ 6.705861] [<ffffffff81fe0f77>] start_kernel+0x42e/0x43b [ 6.707145] [<ffffffff81fe0120>] ? early_idt_handler_array+0x120/0x120 [ 6.708566] [<ffffffff81fe0481>] x86_64_start_reservations+0x2f/0x31 [ 6.724069] [<ffffffff81fe05be>] x86_64_start_kernel+0x13b/0x14a [ 6.725424] Code: 75 05 e8 72 fb ff ff 48 8b 43 60 48 2b 43 50 88 43 4e 5b 5d f3 c3 90 90 90 66 66 90 66 90 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 <f3> 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 f3 [ 6.734615] RIP [<ffffffff81440f12>] __memcpy+0x12/0x20 [ 6.735954] RSP <ffff88013fc03990> [ 6.736965] CR2: ffff8800bffe0000 [ 6.737955] ---[ end trace 711199b99b33e43a ]--- [ 6.739120] Kernel panic - not syncing: Fatal exception in interrupt FYI, raw QEMU command line is: qemu-system-x86_64 -enable-kvm -cpu host -kernel /pkg/linux/x86_64-rhel/gcc-4.9/60edbdb955e718ac4ea403f13edc30d4dc31fbeb/vmlinuz-4.7.0-rc4-00001-g60edbdb -append 'root=/dev/ram0 user=lkp job=/lkp/scheduled/vm-lkp-wsx03-4G-5/bisect_boot-1-debian-x86_64-2015-02-07.cgz-x86_64-rhel-60edbdb955e718ac4ea403f13edc30d4dc31fbeb-20160627-118234-1szxl6h-0.yaml ARCH=x86_64 kconfig=x86_64-rhel branch=linux-devel/devel-hourly-2016062408 commit=60edbdb955e718ac4ea403f13edc30d4dc31fbeb BOOT_IMAGE=/pkg/linux/x86_64-rhel/gcc-4.9/60edbdb955e718ac4ea403f13edc30d4dc31fbeb/vmlinuz-4.7.0-rc4-00001-g60edbdb max_uptime=600 RESULT_ROOT=/result/boot/1/vm-lkp-wsx03-4G/debian-x86_64-2015-02-07.cgz/x86_64-rhel/gcc-4.9/60edbdb955e718ac4ea403f13edc30d4dc31fbeb/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-lkp-wsx03-4G-5::dhcp' -initrd /fs/sdc1/initrd-vm-lkp-wsx03-4G-5 -m 4096 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0,hostfwd=tcp::23644-:22 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -drive file=/fs/sdc1/disk0-vm-lkp-wsx03-4G-5,media=disk,if=virtio -drive file=/fs/sdc1/disk1-vm-lkp-wsx03-4G-5,media=disk,if=virtio -pidfile /dev/shm/kboot/pid-vm-lkp-wsx03-4G-5 -serial file:/dev/shm/kboot/serial-vm-lkp-wsx03-4G-5 -daemonize -display none -monitor null Thanks, Xiaolong