* Borislav Petkov <b...@alien8.de> wrote:
> On Tue, Feb 20, 2018 at 01:29:56PM -0600, Josh Poimboeuf wrote:
> > > Maybe this series already has this side-effect, but I'd really love to
> > > see oopses show the code bytes for each kernel entry, not just the
> > > innermode one. We already dump full regs including RIP -- adding
> > > Code: should be easy and would be very helpful.
> >
> > Just to clarify, I think you want to show the Code: around regs->ip
> > every time we show the registers?
>
> It is an easy change to always dump Code: section when we dump RIP:.
> I.e., something like this:
>
> [ 33.192733] BUG: unable to handle kernel NULL pointer dereference at
> (null)
> [ 33.196510] IP: sysrq_handle_crash+0x17/0x20
> [ 33.196691] PGD 78b12067 P4D 78b12067 PUD 78b7f067 PMD 0
> [ 33.196691] Oops: 0002 [#1] PREEMPT SMP
> [ 33.196691] Modules linked in:
> [ 33.196691] CPU: 6 PID: 3686 Comm: bash Not tainted 4.16.0-rc1+ #5
> [ 33.196691] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.10.2-1 04/01/2014
> [ 33.196691] RIP: 0010:sysrq_handle_crash+0x17/0x20
> [ 33.196691] RSP: 0018:ffffc9000054bdf0 EFLAGS: 00010246
> [ 33.196691] Code: eb d1 e8 5d 17 b7 ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00
> 00 0f 1f 44 00 00 e8 c6 24 bd ff c7 05 24 a2 19 01 01 00 00 00 0f ae f8 <c6>
> 04 25 00 00 00 00 01 c3 0f 1f 44 00 00 e8 86 21 c2 ff fb e9
> [ 33.196691] RAX: 0000000000000000 RBX: 0000000000000063 RCX:
> 0000000000000000
> [ 33.196691] RDX: 0000000000000000 RSI: ffffffff8110145a RDI:
> 0000000000000063
> [ 33.196691] RBP: ffffffff82271400 R08: 0000000000000183 R09:
> 000000000002e771
> [ 33.196691] R10: 0000000000000000 R11: 0000000000000000 R12:
> 000000000000000a
> [ 33.196691] R13: 0000000000000000 R14: 0000000000000000 R15:
> 0000000000000000
> [ 33.196691] FS: 00007ffff7fdb700(0000) GS:ffff88007ed80000(0000)
> knlGS:0000000000000000
> [ 33.196691] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 33.196691] CR2: 0000000000000000 CR3: 000000007aa9e000 CR4:
> 00000000000406e0
> [ 33.196691] Call Trace:
> [ 33.196691] __handle_sysrq+0x9e/0x160
> [ 33.196691] write_sysrq_trigger+0x2b/0x30
> [ 33.196691] proc_reg_write+0x38/0x70
> [ 33.196691] __vfs_write+0x36/0x160
> [ 33.196691] ? __fd_install+0x69/0x110
> [ 33.196691] ? preempt_count_add+0x74/0xb0
> [ 33.196691] ? _raw_spin_lock+0x13/0x30
> [ 33.196691] ? set_close_on_exec+0x41/0x80
> [ 33.196691] ? preempt_count_sub+0xa8/0x100
> [ 33.196691] vfs_write+0xc0/0x190
> [ 33.196691] SyS_write+0x64/0xe0
> [ 33.196691] ? trace_hardirqs_off_thunk+0x1a/0x1c
> [ 33.196691] do_syscall_64+0x70/0x130
> [ 33.196691] entry_SYSCALL_64_after_hwframe+0x42/0xb7
> [ 33.196691] RIP: 0033:0x7ffff74b9620
> [ 33.196691] RSP: 002b:00007fffffffe7a8 EFLAGS: 00000246
> [ 33.196691] Code: ff 73 01 c3 48 8b 0d 68 98 2c 00 f7 d8 64 89 01 48 83 c8
> ff c3 66 0f 1f 44 00 00 83 3d bd f1 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48>
> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ce 8f 01 00 48 89 04
> [ 33.196691] ORIG_RAX: 0000000000000001
> [ 33.196691] RAX: ffffffffffffffda RBX: 0000000000000002 RCX:
> 00007ffff74b9620
> [ 33.196691] RDX: 0000000000000002 RSI: 0000000000705408 RDI:
> 0000000000000001
> [ 33.196691] RBP: 0000000000705408 R08: 000000000000000a R09:
> 00007ffff7fdb700
> [ 33.196691] R10: 00007ffff77826a0 R11: 0000000000000246 R12:
> 00007ffff77842a0
> [ 33.196691] R13: 0000000000000002 R14: 0000000000000001 R15:
> 0000000000000000
> [ 33.196691] Code: eb d1 e8 5d 17 b7 ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00
> 00 0f 1f 44 00 00 e8 c6 24 bd ff c7 05 24 a2 19 01 01 00 00 00 0f ae f8 <c6>
> 04 25 00 00 00 00 01 c3 0f 1f 44 00 00 e8 86 21 c2 ff fb e9
> [ 33.196691] RIP: sysrq_handle_crash+0x17/0x20 RSP: ffffc9000054bdf0
> [ 33.196691] CR2: 0000000000000000
> [ 33.301033] ---[ end trace b97275941de8c6f4 ]---
> [ 33.302600] Kernel panic - not syncing: Fatal exception
> [ 33.304529] Kernel Offset: disabled
> [ 33.304973] ---[ end Kernel panic - not syncing: Fatal exception
That looks really useful!
Thanks,
Ingo
