一段时间以来，我遇到了一个问题，即我的服务器在没有任何可识别原因的情况下崩溃了。昨天，我终于能够“捕获我的服务器”崩溃并防止日志在重新启动时被擦除。我发现了以下内容：
Sep 1 19:04:30 DebianHomeServer kernel: [11437.330427] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
Sep 1 19:04:30 DebianHomeServer kernel: [11437.330597] IP: [<ffffffffc06bec04>] ext4_file_open+0x24/0x280 [ext4]
Sep 1 19:04:30 DebianHomeServer kernel: [11437.333407] PGD 0
Sep 1 19:04:30 DebianHomeServer kernel: [11437.333451]
Sep 1 19:04:30 DebianHomeServer kernel: [11437.333553] Oops: 0002 [#808] SMP
Sep 1 19:04:30 DebianHomeServer kernel: [11437.333615] Modules linked in: ipt_REJECT nf_reject_ipv4 xt_multiport iptable_filter edac_mce_amd edac_core snd_hda_codec_realtek kvm snd_hda_codec_hdmi joydev snd_hda_codec_generic evdev snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep irqbypass serio_raw snd_pcm pcspkr snd_timer k10temp snd sg soundcore shpchp wmi sp5100_tco button acpi_cpufreq nvidia_drm(PO) drm_kms_helper drm nvidia_modeset(PO) nvidia(PO) ipmi_msghandler it87 hwmon_vid ip_tables x_tables autofs4 ext4 crc16 jbd2 fscrypto ecb glue_helper lrw gf128mul ablk_helper cryptd aes_x86_64 mbcache raid10 raid1 raid0 multipath linear raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic hid_generic usbhid hid md_mod sd_mod ohci_pci firewire_ohci ata_generic xhci_pci ehci_pci xhci_hcd ohci_hcd
Sep 1 19:04:30 DebianHomeServer kernel: [11437.337130] ehci_hcd firewire_core crc_itu_t i2c_piix4 pata_atiixp usbcore usb_common r8169 mii ahci libahci pata_jmicron libata scsi_mod floppy
Sep 1 19:04:30 DebianHomeServer kernel: [11437.337824] CPU: 2 PID: 16273 Comm: apache2 Tainted: P D O 4.9.0-9-amd64 #1 Debian 4.9.168-1+deb9u5
Sep 1 19:04:30 DebianHomeServer kernel: [11437.337911] Hardware name: Gigabyte Technology Co., Ltd. GA-890XA-UD3/GA-890XA-UD3, BIOS FA 04/13/2010
Sep 1 19:04:30 DebianHomeServer kernel: [11437.337996] task: ffff9debe5b30e40 task.stack: ffffb75800b84000
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338062] RIP: 0010:[<ffffffffc06bec04>] [<ffffffffc06bec04>] ext4_file_open+0x24/0x280 [ext4]
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338219] RSP: 0018:ffffb75800b87dd0 EFLAGS: 00010206
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338284] RAX: 0000000000000048 RBX: ffff9debea20cbc8 RCX: 000000009b45f3a4
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338352] RDX: 39aa73a454b04281 RSI: 000000009b45f3a4 RDI: 0000000000000000
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338421] RBP: ffffb75800b87e80 R08: 0000000000000000 R09: ffff9debea1b02d8
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338489] R10: ffff9debe630e400 R11: 000000000000000c R12: ffff9debea20cbc8
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338557] R13: ffffb75800b87ed0 R14: ffff9deb8aec9e80 R15: ffff9debc4830300
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338627] FS: 00007fd7bc4f1040(0000) GS:ffff9debefc80000(0000) knlGS:0000000000000000
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338710] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338776] CR2: 0000000000000048 CR3: 000000012353e000 CR4: 00000000000006f0
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338843] Stack:
Sep 1 19:04:30 DebianHomeServer kernel: [11437.338902] 8b2a0dff7c28f1f0 ffff9debeab0f000 00000000024000c0 ffff9debe295d400
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339145] ffff9debea20cbc8 0002000000000000 0000000000000000 ffff9debc4830300
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339386] ffff9debe61d5800 0000000000000000 8000000100000000 ffff9deb00000000
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339627] Call Trace:
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339696] [<ffffffffa6e20b37>] ? iterate_dir+0x177/0x1a0
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339765] [<ffffffffa6e21028>] ? SyS_getdents+0x98/0x120
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339832] [<ffffffffa6e20d90>] ? fillonedir+0xe0/0xe0
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339901] [<ffffffffa6c03b7d>] ? do_syscall_64+0x8d/0x100
Sep 1 19:04:30 DebianHomeServer kernel: [11437.339970] [<ffffffffa721b80e>] ? entry_SYSCALL_64_after_swapgs+0x58/0xc6
Sep 1 19:04:30 DebianHomeServer kernel: [11437.340038] Code: 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 41 55 41 54 55 53 48 89 f5 48 89 fb 48 83 ec 60 4c 8b 6f 28 65 48 8b 04 25 28 00 <00> 00 48 89 44 24 58 31 c0 4d 8b bd 60 04 00 00 41 8b 97 80 00
Sep 1 19:04:30 DebianHomeServer kernel: [11437.342767] RIP [<ffffffffc06bec04>] ext4_file_open+0x24/0x280 [ext4]
Sep 1 19:04:30 DebianHomeServer kernel: [11437.342905] RSP <ffffb75800b87dd0>
Sep 1 19:04:30 DebianHomeServer kernel: [11437.342966] CR2: 0000000000000048
Sep 1 19:04:30 DebianHomeServer kernel: [11437.343094] ---[ end trace 0fc6e2d0e65772fc ]---
我使用的是 Debian 9.9，内核版本为 Linux 4.9.0-9-amd64 #1 SMP Debian 4.9.168-1+deb9u5 日志比上面的摘录长得多，但我无法在此处粘贴所有详细信息因为有近 80,000 行。第一个完整条目是
Sep 1 01:09:06 DebianHomeServer kernel: [481098.461181] Fixing recursive fault but reboot is needed!
Sep 1 01:09:06 DebianHomeServer kernel: [481098.461188] BUG: unable to handle kernel NULL pointer dereference at (null)
Sep 1 01:09:06 DebianHomeServer kernel: [481098.461193] IP: [<ffffffffa3b095c4>] blk_flush_plug_list+0x74/0x230
Sep 1 01:09:06 DebianHomeServer kernel: [481098.461201] PGD 0
Oops: 0002 [#4715] SMP
如果需要，我可以提供更多详细信息，但如果我能得到一些有关问题所在的反馈，我真的非常非常感激。