FYI, we noticed the below changes on https://github.com/0day-ci/linux SF-Markus-Elfring/net-scm-Delete-an-unnecessary-check-before-the-function-call-kfree/20151118-004536 commit 0581888c8c2bba0b9a906a38198edb064da95947 ("net-scm: Delete an unnecessary check before the function call "kfree"") +------------------------------------------+------------+------------+ | | c5a37883f4 | 0581888c8c | +------------------------------------------+------------+------------+ | boot_successes | 375 | 16 | | boot_failures | 35 | 7 | | BUG:unable_to_handle_kernel | 31 | 6 | | Oops | 31 | 6 | | RIP:drm_calc_timestamping_constants[drm] | 31 | | | Kernel_panic-not_syncing:Fatal_exception | 31 | 6 | | backtrace:drm_fb_helper_initial_config | 31 | | | backtrace:mgag200_fbdev_init | 31 | | | backtrace:mgag200_modeset_init | 31 | | | backtrace:__pci_register_driver | 22 | | | backtrace:drm_pci_init | 22 | | | backtrace:mgag200_init | 22 | | | backtrace:do_init_module | 22 | | | backtrace:load_module | 22 | | | backtrace:SyS_finit_module | 22 | | | backtrace:work_for_cpu_fn | 9 | | | backtrace:vc_resize | 20 | | | backtrace:fbcon_init | 20 | | | backtrace:visual_init | 20 | | | BUG:kernel_test_crashed | 2 | 1 | | page_allocation_failure:order:#,mode | 2 | | | warn_alloc_failed+0x | 2 | | | Mem-Info | 2 | | | backtrace:blk_mq_run_work_fn | 1 | | | backtrace:wb_workfn | 1 | | | RIP:__scm_send | 0 | 6 | | backtrace:__sys_sendmsg | 0 | 6 | | backtrace:SyS_sendmsg | 0 | 6 | +------------------------------------------+------------+------------+ [ 19.225937] systemd-journald[129]: Compressed data object 889 -> 592 [ 19.254790] systemd-journald[129]: Compressed data object 896 -> 596 [ 19.339352] systemd-journald[129]: systemd-journald running as pid 129 [ 19.369988] BUG: unable to handle kernel NULL pointer dereference at (null) [ 19.372715] IP: [] __scm_send+0xd9/0x400 [ 19.380400] PGD 0 [ 19.381544] Oops: 0000 [#1] SMP [ 19.385130] Modules linked in: [ 19.386531] CPU: 2 PID: 129 Comm: systemd-journal Not tainted 4.3.0-11482-g0581888 #1 [ 19.400858] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 19.400861] task: ffff88013289a400 ti: ffff88007f7c8000 task.ti: ffff88007f7c8000 [ 19.400870] RIP: 0010:[] [] __scm_send+0xd9/0x400 [ 19.400871] RSP: 0018:ffff88007f7cbbf8 EFLAGS: 00010283 [ 19.400873] RAX: ffff88007f7cbd58 RBX: ffff88007f7cbec8 RCX: 0000000000000000 [ 19.400874] RDX: 000000000000001c RSI: 0000000000000030 RDI: 0000000000000000 [ 19.400874] RBP: ffff88007f7cbc60 R08: 0000000000000000 R09: 0000000000000001 [ 19.400875] R10: ffff88007f75e5c0 R11: ffff88013289a400 R12: 0000000000000000 [ 19.400876] R13: ffff88007f7cbcb8 R14: ffff88013a6e1f80 R15: ffff88007f7cbd78 [ 19.400878] FS: 00007fed50157840(0000) GS:ffff88013fd00000(0000) knlGS:0000000000000000 [ 19.400879] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 19.400880] CR2: 0000000000000000 CR3: 000000007f680000 CR4: 00000000000006e0 [ 19.400884] Stack: [ 19.400887] 0000000000000000 ffff88013289a400 ffff88013289a400 ffff88013289a400 [ 19.400889] ffff88013289a400 ffff880137f64280 ffffffff00000000 ffff880000000075 [ 19.400890] ffff880137f64280 ffff8801328d4380 ffff88007f7cbec8 0000000000000000 [ 19.400891] Call Trace: [ 19.400900] [] unix_dgram_sendmsg+0x294/0x5d0 [ 19.400906] [] ? rw_copy_check_uvector+0x91/0x130 [ 19.400910] [] sock_sendmsg+0x38/0x50 [ 19.400912] [] ___sys_sendmsg+0x285/0x290 [ 19.400916] [] ? filemap_map_pages+0x221/0x230 [ 19.400919] [] ? handle_mm_fault+0xedf/0x1940 [ 19.400921] [] ? unmap_region+0xd3/0x100 [ 19.400925] [] ? __might_sleep+0x52/0xb0 [ 19.400927] [] __sys_sendmsg+0x42/0x80 [ 19.400929] [] SyS_sendmsg+0x12/0x20 [ 19.400933] [] entry_SYSCALL_64_fastpath+0x12/0x71 [ 19.400952] Code: 7f 08 01 74 40 49 8b 07 48 8b 53 40 48 83 c0 07 48 83 e0 f8 49 01 c7 48 8b 43 38 49 8d 77 10 48 29 c6 48 39 f2 73 b6 49 8b 7d 08 <66> 83 3f 00 75 0d e8 ec a3 a4 ff 49 c7 45 08 00 00 00 00 31 db [ 19.400954] RIP [] __scm_send+0xd9/0x400 [ 19.400954] RSP [ 19.400955] CR2: 0000000000000000 [ 19.400995] ---[ end trace 49b061cf3619cad8 ]--- [ 19.400996] Kernel panic - not syncing: Fatal exception Thanks, Ying Huang