Re: [Xen-devel] So I tried to use xentrace...

[Jeremy Fitzhardinge <jeremy@xxxxxxxx>]

On 05/07/2010 01:48 PM, George Dunlap wrote:
> Hmm, -S 256 is an obsolete size; it should be something more like -S 32.
>
> However, I added a patch that was supposed to do appropriate
> bounds-checking and return an error if the number was too high.  Looks
> like it's not working properly for some reason...  I'll take a look.
>
>  -George
>
> On Fri, Apr 30, 2010 at 4:34 PM, Jeremy Fitzhardinge <jeremy@xxxxxxxx> wrote:
>   
>> When I ran "xentrace -D -S 256 -e all /tmp/test.trace" from the
>> xenanalyze documentation, Xen immediately crashed with:
>>
>> (XEN) tbuf_size 256
>> (XEN) p0 mfn 106a00 offset 64
>> (XEN) p1 mfn 115700 offset 320
>> (XEN) p2 mfn 113f00 offset 576
>> (XEN) p3 mfn 113e00 offset 832
>> (XEN) Xen trace buffers: initialized
>> (XEN) ----[ Xen-4.1-unstable  x86_64  debug=y  Not tainted ]----
>> (XEN) CPU:    1
>> (XEN) RIP:    e008:[<ffff82c4801215b3>] check_lock+0x1b/0x45
>>     

This suggests the problem is with misusing a lock in the wrong interrupt
context, rather than anything to do with sizes.

    J

>> (XEN) RFLAGS: 0000000000010246   CONTEXT: hypervisor
>> (XEN) rax: 0000000000000001   rbx: 0000000000000028   rcx: 0000000000000000
>> (XEN) rdx: 0000000000000000   rsi: 00000000c3fc8050   rdi: 000000000000002c
>> (XEN) rbp: ffff83013ff2fc60   rsp: ffff83013ff2fc60   r8:  ffff8300bf78a000
>> (XEN) r9:  ffff83013ff60000   r10: 0080000000000001   r11: ffff82f60164b930
>> (XEN) r12: 00000000c3fc8050   r13: 00000000c3fc8050   r14: 0000000000000028
>> (XEN) r15: 0000000000800627   cr0: 000000008005003b   cr4: 00000000000026f0
>> (XEN) cr3: 00000000b2fa0000   cr2: 000000000000002c
>> (XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: e010   cs: e008
>> (XEN) Xen stack trace from rsp=ffff83013ff2fc60:
>> (XEN)    ffff83013ff2fc78 ffff82c480121993 0000000000000000 ffff83013ff2fca8
>> (XEN)    ffff82c480117fe0 ffff83013fee0000 80000c3fc8050627 00000000c3fc8050
>> (XEN)    ffff83013ff60000 ffff83013ff2fd28 ffff82c48016538c ffff8800aec97b08
>> (XEN)    ffff83013ff2fcf0 00000000000b25c9 0000000000000100 ffff8300bf78a000
>> (XEN)    0000000000000206 0000000000000000 ffff830e7f900a00 ffff83013ff2fd28
>> (XEN)    ffff8300b25c9228 ffff8300bf78a000 0000000000800627 0000000000000000
>> (XEN)    0000000000000000 ffff83013ff2fdb8 ffff82c48016a9f7 ffff83013fee0018
>> (XEN)    00007ff03ff2ff28 0000000000000000 00000000000b25c9 ffff83013fee0000
>> (XEN)    80000c3fc8050627 80000c3fc8050627 ffff83013ff60000 ffff83013ff2fdb8
>> (XEN)    0000000180162c10 ffff83013ff2fdd8 0000000000000000 0000000000000000
>> (XEN)    ffff8800aec97bb8 ffff83013ff2ff28 ffff83013ff2ff28 ffff83013ff2ff08
>> (XEN)    ffff82c48016b2a9 0000000000000000 0000000000000000 0000000000000000
>> (XEN)    00000000bf78a000 0000000000000006 00000000b2e55067 ffff83013ff2ff28
>> (XEN)    ffff83013ff2ff28 ffff83013ff2ff28 ffff83013ff2ff28 ffff83013ff2ff28
>> (XEN)    ffff83013ff2ff28 ffff83013ff2ff28 ffff83013ff2ff28 0000000000000000
>> (XEN)    00007ff200000082 ffff83013ff2fe68 80000c3fc8050627 ffff8300bf78a000
>> (XEN)    ffff8300b25c9228 ffff83013ff2fee8 ffff82f60164b920 ffff83013fee0000
>> (XEN)    000000000003e6b8 00000000000b25c9 00000001032cc060 ffff83013ff60000
>> (XEN)    0000000000000000 aaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaa 00000001aaaaaaaa
>> (XEN)    0000000000000001 00000000b25c9228 80000c3fc8050627 ffff8800aec97bb8
>> (XEN) Xen call trace:
>> (XEN)    [<ffff82c4801215b3>] check_lock+0x1b/0x45
>> (XEN)    [<ffff82c480121993>] _spin_lock+0x11/0x3f
>> (XEN)    [<ffff82c480117fe0>] rangeset_contains_range+0x44/0x82
>> (XEN)    [<ffff82c48016538c>] get_page_from_l1e+0x24c/0x47f
>> (XEN)    [<ffff82c48016a9f7>] mod_l1_entry+0x47f/0x64e
>> (XEN)    [<ffff82c48016b2a9>] do_mmu_update+0x6e3/0x1962
>> (XEN)    [<ffff82c4801f71bf>] syscall_enter+0xef/0x149
>> (XEN)
>> (XEN) Pagetable walk from 000000000000002c:
>> (XEN)  L4[0x000] = 00000000b2c3a067 00000000000aecc5
>> (XEN)  L3[0x000] = 00000000b2c70067 00000000000aec8f
>> (XEN)  L2[0x000] = 0000000000000000 ffffffffffffffff
>> (XEN)
>> (XEN) ****************************************
>> (XEN) Panic on CPU 1:
>> (XEN) FATAL PAGE FAULT
>> (XEN) [error_code=0000]
>> (XEN) Faulting linear address: 000000000000002c
>> (XEN) ****************************************
>> (XEN)
>> (XEN) Reboot in five seconds...
>>
>>        J
>>
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>> http://lists.xensource.com/xen-devel
>>
>>     
>   


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel