Arch Linux

When trying to unlock an encrypted partition kcryptd dies with a NULL pointer dereference. This happens like every second try.


BUG: unable to handle kernel NULL pointer dereference at virtual address 0000000d
printing eip:
c015d4d8
*pde = 00000000
Oops: 0000 [#1]
PREEMPT SMP
Modules linked in: wacom nvidia(P) ipv6 capability commoncap sha256 nls_cp437 vfat fat ext2 ppdev lp usb_storage ide_core analog hisax crc_ccitt isdn pcspkr ppp_generic parport_pc parport rtc_cmos slhc ns558 rtc_core rtc_lib psmouse serio_raw k8temp emu10k1_gp gameport i2c_ali15x3 i2c_ali1535 sg amd64_agp ali_agp agpgart shpchp pci_hotplug i2c_ali1563 i2c_core thermal tsdev fan joydev evdev button battery ac aes dm_crypt dm_mod usbhid hid ff_memless snd_seq_oss cpufreq_ondemand powernow_k8 freq_table processor snd_seq_midi_event snd_seq snd_emu10k1 snd_pcm_oss snd_mixer_oss snd_rawmidi snd_ac97_codec ac97_bus snd_pcm snd_seq_device snd_timer snd_page_alloc snd_util_mem snd_hwdep snd soundcore uli526x ext3 jbd mbcache ehci_hcd sr_mod cdrom ohci_hcd usbcore sd_mod ahci ata_generic pata_ali libata
CPU: 0
EIP: 0060:[<c015d4d8>] Tainted: P VLI
EFLAGS: 00010282 (2.6.22-ARCH #1)
EIP is at mempool_free+0x18/0xa0
eax: f7578894 ebx: 00000001 ecx: 00000000 edx: 00000001
esi: f75a0bc0 edi: f7578894 ebp: f8970920 esp: f7e4fef4
ds: 007b es: 007b fs: 00d8 gs: 0000 ss: 0068
Process kcryptd/0 (pid: 1869, ti=f7e4e000 task=dfc77030 task.ti=f7e4e000)
Stack: f8970920 f8b38080 f75a0bc0 f7e4ff4c f8970c46 f79179c0 000000f9 00000000
00000000 f7578894 c035269f f7e4ffa8 c03526c1 00000002 f7e4ff94 f7e4ff90
00000000 dfc77030 037615e9 c046aa00 c046aa00 61e96712 f79179c0 f79179c0
Call Trace:
[<f8970920>] kcryptd_do_work+0x0/0x360 [dm_crypt]
[<f8970c46>] kcryptd_do_work+0x326/0x360 [dm_crypt]
[<c035269f>] schedule+0x2cf/0x8e0
[<c03526c1>] schedule+0x2f1/0x8e0
[<f8970920>] kcryptd_do_work+0x0/0x360 [dm_crypt]
[<c013b906>] run_workqueue+0x86/0x110
[<c013c2c0>] worker_thread+0x0/0xe0
[<c013c344>] worker_thread+0x84/0xe0
[<c013f460>] autoremove_wake_function+0x0/0x40
[<c013c2c0>] worker_thread+0x0/0xe0
[<c013f192>] kthread+0x42/0x70
[<c013f150>] kthread+0x0/0x70
[<c0104fff>] kernel_thread_helper+0x7/0x18
=======================
Code: 74 26 00 89 d1 89 c2 89 c8 e9 25 9a 01 00 90 8d 74 26 00 83 ec 10 89 5c 24 04 89 d3 89 7c 24 0c 89 c7 89 74 24 08 0f ae f0 66 90 <8b> 42 0c 3b 42 08 7d 59 89 d0 e8 49 78 1f 00 89 c6 8b 43 0c 3b
EIP: [<c015d4d8>] mempool_free+0x18/0xa0 SS:ESP 0068:f7e4fef4


According to http://bugzilla.kernel.org/show_bug.cgi?id=7388 this is a known problem. The attached patch fixes it for me.