On Tue, Jun 10, 2008 at 7:15 PM, Larry Finger <Larry.Finger@xxxxxxxxxxxx> wrote: > Miles Lane wrote: >> >> I got a slightly different BUG with this patch applied: >> >> BUG: unable to handle kernel NULL pointer dereference at 00000000 >> IP: [<f89e3d41>] :b43:b43_dma_mapping_error+0x16/0x97 >> *pde = 00000000 >> Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC >> last sysfs file: >> >> /sys/devices/pci0000:00/0000:00:08.0/0000:01:06.0/ssb0:0/firmware/ssb0:0/loading >> Modules linked in: sbs sbshc wmi battery iptable_filter ip_tables >> x_tables ac sbp2 rtc arc4 ecb crypto_blkcipher cryptomgr crypto_algapi >> b43 mac80211 cfg80211 led_class snd_intel8x0 snd_ac97_codec ac97_bus >> snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss >> snd_seq_midi_event snd_seq snd_timer snd_seq_device snd soundcore >> snd_page_alloc i2c_nforce2 i2c_core button ohci1394 3c59x ieee1394 >> forcedeth ehci_hcd ohci_hcd usbcore thermal processor fan thermal_sys > > Miles, > > If you have time, please cd to the kernel root directory and run the command > 'objdump -d -l drivers/net/wireless/b43/dma.o > dmadump'. You may have to > install the objdump package. In the file dmadump, find the line that > contains b43_dma_mapping_error. On my system it is 0000000000000085 > <b43_dma_mapping_error>: Note, I use x86_64 and yours will likely be > different. > > Note the address (0x85 in my case), add the offset (0x16) and find the line > with the error. You can use KCalc in hexadecimal mode if you are not > comfortable with doing addition in base 16. Please report the source line > and instruction that failed. For me, the line is: "000000ab <b43_dma_mapping_error>:" so, 0xab + 0x16 = 0xc1 and here's the dump giving some context around that line: b43_dma_mapping_error(): ab: 55 push %ebp ac: 89 e5 mov %esp,%ebp ae: 57 push %edi af: 89 d7 mov %edx,%edi b1: 56 push %esi b2: 89 ce mov %ecx,%esi b4: 53 push %ebx b5: 83 ec 08 sub $0x8,%esp b8: 8a 55 08 mov 0x8(%ebp),%dl bb: 88 55 ef mov %dl,-0x11(%ebp) be: 8b 50 58 mov 0x58(%eax),%edx c1: 8b 12 mov (%edx),%edx c3: 8b 52 08 mov 0x8(%edx),%edx c6: 89 55 f0 mov %edx,-0x10(%ebp) c9: 8b 40 34 mov 0x34(%eax),%eax cc: 83 f8 1e cmp $0x1e,%eax cf: 74 07 je d8 <b43_dma_mapping_error+0x2d> d1: 83 f8 20 cmp $0x20,%eax d4: 75 5b jne 131 <b43_dma_mapping_error+0x86> d6: eb 15 jmp ed <b43_dma_mapping_error+0x42> I hope this helps. Miles -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html