----- "Reinoud Koornstra" <koornstra@xxxxxx> wrote: > > -----Original Message----- > > From: crash-utility-bounces@xxxxxxxxxx [mailto:crash-utility- > > bounces@xxxxxxxxxx] On Behalf Of Dave Anderson > > Sent: Thursday, August 12, 2010 12:18 PM > > To: Discussion list for crash utility usage, maintenance and > > development > > Subject: Re: crash: invalid structure member offset > > > > > > ----- "Reinoud Koornstra" <koornstra@xxxxxx> wrote: > > > > > Thanks, > > > > > > Using crash 5.0.6 worked nicely. > > > However, I can't really look at a lot because of a bad EIP code. > > > > > > [ 726.601381] 802.1Q VLAN Support v1.8 Ben Greear <greearb@xxxxxxxxxxxxxxx> > > > [ 726.601384] All bugs added by David S. Miller <davem@xxxxxxxxxx> > > > [ 726.646757] BUG: unable to handle kernel NULL pointer dereference at 00000000 > > > [ 726.732410] IP: [<00000000>] > > > [ 726.766933] *pdpt = 0000000000431001 *pde = 0000000000000000 > > > [ 726.766937] Oops: 0010 [#1] SMP > > > [ 726.790844] Modules linked in: 8021q iptable_filter ip_tables > > > x_tables ip_gre af_packet i2c_dev i2c_qs i2c_algo_bit i2c_core garp > > > stp llc ixgbe inet_lro psmouse serio_raw intel_agp shpchp iTCO_wdt > > > pci_hotplug iTCO_vendor_support agpgart ext3 jbd mbcache sd_mod > > > crc_t10dif sg ata_piix ata_generic ahci libata scsi_mod ehci_hcd > > > uhci_hcd usbcore [last unloaded: 8021q] > > > [ 726.790844] > > > [ 726.790844] Pid: 4, comm: ksoftirqd/0 Tainted: P (2.6.27) > > > [ 726.790844] EIP: 0060:[<00000000>] EFLAGS: 00010202 CPU: 0 > > > [ 726.790844] EIP is at 0x0 > > > [ 726.790844] EAX: e7f4c498 EBX: 00000000 ECX: 77470000 EDX: e7f4c498 > > > [ 726.790844] ESI: 4bd1d300 EDI: 00000007 EBP: f784df88 ESP: f784df78 > > > [ 726.790844] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 > > > [ 726.790844] Process ksoftirqd/0 (pid: 4, ti=f784c000 task=f783a5b0 task.ti=f784c000) > > > [ 726.790844] Stack: 40168080 00000001 403daaa0 4042c500 f784df90 401681bf f784dfb0 4012fe92 > > > [ 726.790844] 0000000a 00000000 40429340 00000246 00000000 40130120 f784dfbc 4012ff55 > > > [ 726.790844] 4042c500 f784dfcc 40130182 fffffffc 00000000 > > f784dfe0 4013e707 4013e6c0 > > > [ 726.790844] Call Trace: > > > [ 726.790844] [<40168080>] ? __rcu_process_callbacks+0x70/0x190 > > > [ 726.790844] [<401681bf>] ? rcu_process_callbacks+0x1f/0x40 > > > [ 726.790844] [<4012fe92>] ? __do_softirq+0x82/0x100 > > > [ 726.790844] [<40130120>] ? ksoftirqd+0x0/0xe0 > > > [ 726.790844] [<4012ff55>] ? do_softirq+0x45/0x50 > > > [ 726.790844] [<40130182>] ? ksoftirqd+0x62/0xe0 > > > [ 726.790844] [<4013e707>] ? kthread+0x47/0x80 > > > [ 726.790844] [<4013e6c0>] ? kthread+0x0/0x80 > > > [ 726.790844] [<4010494f>] ? kernel_thread_helper+0x7/0x10 > > > [ 726.790844] ======================= > > > [ 726.790844] Code: Bad EIP value. > > > [ 726.790844] EIP: [<00000000>] 0x0 SS:ESP 0068:f784df78 > > > > > > So now I can't figure out the piece of code where this dereferencing > > > occurred. :( > > > > Yeah, I don't know why the exception frame didn't displayed below in the > > bt output, but I think it may have been confusion due the kernel text > > region starting a 4000000 (instead of the typical 3G/1G user/kernel virtual > > address split). I'm guessing your kernel is configured as 1G/3G user-kernel? > > That's right, the kernel is configured as 1G/3G user/kernel. > > > (I've never seen that before...) > > It's a weird config indeed. I'll try rewriting some stuff so it > consumes way less memory so a normal kernel/user split can be used. > Never the less, why the pointer became null remains unsolved for the moment. :-) > Would the user/kernel split also be an issue in 64 bit? I wouldn't expect you'd ever need to modify the user-kernel split in x86_64, if that's what you're asking? The 64-bit virtual address range is so vast that it's hard to conceive of a need to do anything like that. Dave -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility
