BUG: x86-64 VT crash backtrace

[Rik van Riel <riel@redhat.com>]

Hi Jun,

here is the x86-64 VT crash backtrace, as promised.  I can trigger it 
within minutes by simply starting up a 64 bit VT domain on a 64 bit system.

(XEN) ----[ Xen-3.0-unstable    Not tainted ]----
(XEN) CPU:    1
(XEN) RIP:    e010:[<ffff830000153cc8>] __cpus_subset+0x0/0x25
(XEN) RFLAGS: 0000000000010082   CONTEXT: hypervisor
(XEN) rax: 0000000000000001   rbx: ffff830000ff7068   rcx: 0000000000000020
(XEN) rdx: 0000000000000020   rsi: ffff83000024db08   rdi: ffff830000ff7010
(XEN) rbp: ffff830000ff7018   rsp: ffff830000ff7000   r8:  0000000000000000
(XEN) r9:  0000010010bc7bc8   r10: 0000000000000004   r11: 00000000006bc6b0
(XEN) r12: ffffffff804bc220   r13: 00000100108e8230   r14: ffffffff804bc1a0
(XEN) r15: 00000004a0c7d6d9   cr0: 000000008005003b   cr3: 0000000041137000
(XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: 0000   cs: e010
(XEN) Xen stack trace from rsp=ffff830000ff7000:
(XEN)    ffff830000153c20 0000000000000000 0000000000000001 ffff830000ff7058
(XEN)    ffff830000153ba8 000000fc00ff7068 0000000000000001 ffff830000ff7058
(XEN)    0000000000000001 0000002000ff7068 ffff830000ff7068 ffff830000ff7078
(XEN)    ffff830000154489 0000000000000001 000000000001053d ffff830000ff70a8
(XEN)    ffff83000011da63 0000000100ff70a8 0000000000000001 0000002000ff70c8
(XEN)    0000002000ff70c8 ffff830000ff70d8 ffff83000011d81e ffff830000268d80
(XEN)    0000000000ffee80 0000000000000001 ffff830000ffed80 ffff830000ff7108
(XEN)    ffff83000011d516 000000125d845e14 ffff830000fee080 ffff830000268d80
(XEN)    000000000001053d ffff830000ff7138 ffff830000123e40 ffff830000fee138
(XEN)    ffff830000fee080 0000000000000000 0000000000000086 ffff830000ff7158
(XEN)    ffff83000010c60b ffff830000fee138 ffff830000fee080 ffff830000ff7188
(XEN)    ffff83000010c595 ffff83000020b000 ffff830000fee080 0000001000000000
(XEN)    0000000000000000 ffff830000ff71a8 ffff83000010c566 0000000000000000
(XEN)    ffff830000fee080 ffff830000ff71d8 ffff83000010c471 0000000f00000000
(XEN)    ffff830000fee080 ffff830000268080 ffff83000020b000 ffff830000ff7208
(XEN)    ffff83000010c85e 0000001500268408 ffff830000268080 0000000f00208c88
(XEN)    ffff8300002031e8 ffff830000ff7258 ffff830000141399 ffff830000ff7238
(XEN)    000000c00012d383 0000001500ff7258 ffff83000023cf80 ffff830000208c80
(XEN)    ffff830000268080 000000000a4011c4 0000000100000000 ffff830000ff7298
(XEN)    ffff830000140cbf fdb3830000f77020 ffff830000ff72a8 0000000000000004
(XEN) Xen call trace:
(XEN)    [<ffff830000153cc8>] __cpus_subset+0x0/0x25
(XEN)    [<ffff830000153ba8>] send_IPI_mask_flat+0x20/0x77
(XEN)    [<ffff830000154489>] smp_send_event_check_mask+0x51/0x58
(XEN)    [<ffff83000011da63>] cpumask_raise_softirq+0x74/0x76
(XEN)    [<ffff83000011d81e>] __runq_tickle+0x192/0x194
(XEN)    [<ffff83000011d516>] csched_vcpu_wake+0xf5/0xf7
(XEN)    [<ffff830000123e40>] vcpu_wake+0x68/0xf9
(XEN)    [<ffff83000010c60b>] vcpu_unblock+0x2e/0x30
(XEN)    [<ffff83000010c595>] vcpu_kick+0x2d/0x51
(XEN)    [<ffff83000010c566>] vcpu_mark_events_pending+0x2e/0x30
(XEN)    [<ffff83000010c471>] evtchn_set_pending+0x87/0x107
(XEN)    [<ffff83000010c85e>] send_guest_pirq+0xce/0xd0
(XEN)    [<ffff830000141399>] __do_IRQ_guest+0x2f6/0x30b
(XEN)    [<ffff830000140cbf>] do_IRQ+0x65/0x1bf
(XEN)    [<ffff83000013c196>] common_interrupt+0x26/0x30
(XEN)    [<ffff830000117cd6>] free_heap_pages+0x330/0x3b0
(XEN)    [<ffff8300001198e3>] free_domheap_pages+0x54f/0x57b
(XEN)    [<ffff83000016e9bb>] free_shadow_page+0x3d3/0x3da
(XEN)    [<ffff83000016e23f>] put_shadow_ref+0x16f/0x171
(XEN)    [<ffff83000016e0b2>] shadow_free_snapshot+0x2e3/0x2e5
(XEN)    [<ffff83000016e31a>] release_out_of_sync_entry+0xd9/0xdb
(XEN)    [<ffff83000016e4fc>] remove_out_of_sync_entries+0xac/0xf0
(XEN)    [<ffff83000016f41e>] shadow_demote+0x120/0x122
(XEN)    [<ffff83000016e80d>] free_shadow_page+0x225/0x3da
(XEN)    [<ffff83000016e23f>] put_shadow_ref+0x16f/0x171
(XEN)    [<ffff83000016f7b6>] free_shadow_tables+0x1c3/0x294
(XEN)    [<ffff83000016e85e>] free_shadow_page+0x276/0x3da
(XEN)    [<ffff83000016e23f>] put_shadow_ref+0x16f/0x171
(XEN)    [<ffff83000016f7b6>] free_shadow_tables+0x1c3/0x294
(XEN)    [<ffff83000016e85e>] free_shadow_page+0x276/0x3da
(XEN)    [<ffff830000167346>] put_shadow_ref+0x16f/0x171
(XEN)    [<ffff830000167466>] validate_entry_change+0x11e/0x130
(XEN)    [<ffff8300001683b0>] resync_all+0xa56/0xc47
(XEN)    [<ffff830000168839>] resync_all_levels_guest_page+0x9a/0xa2
(XEN)    [<ffff830000168a1a>] sync_all+0x1d9/0x218
(XEN)    [<ffff83000016d8d1>] __shadow_sync_all+0x21/0x23
(XEN)    [<ffff8300001b276b>] shadow_sync_all+0xa3/0x1b5
(XEN)    [<ffff8300001b406e>] mov_to_cr+0x4e7/0xb70
(XEN)    [<ffff8300001b4c1b>] vmx_cr_access+0x114/0x4d5
(XEN)    [<ffff8300001b5ea3>] vmx_vmexit_handler+0xbd3/0x1101
(XEN)
(XEN) ************************************
(XEN) CPU1 FATAL TRAP 8 (double fault), ERROR_CODE 0000, IN INTERRUPT 
CONTEXT.
(XEN) System shutting down -- need manual reset.
(XEN) ************************************


-- 
"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are,
by definition, not smart enough to debug it." - Brian W. Kernighan