KDL in messaging command processor

[kallisti5]

Not sure of the cause, but got the following KDL with the following configuration:

• hrev49658 x86_64
• libvirtd vm under linux kvm
• virtio block storage
• boot machine
• eventually see kdl below

KDL

kdebug> bt
stack trace for thread 313 "messaging command processor"
    kernel stack: 0xffffffff818b6000 to 0xffffffff818bb000
      user stack: 0x00007f11ab200000 to 0x00007f11ab240000
frame                       caller             <image>:function + offset
 0 ffffffff818ba468 (+  32) ffffffff800a38f9   <kernel_x86_64> invoke_command_trampoline(void*) + 0x19
 1 ffffffff818ba488 (+  24) ffffffff801308bc   <kernel_x86_64> arch_debug_call_with_fault_handler + 0x16
 2 ffffffff818ba4a0 (+  96) ffffffff800a10ac   <kernel_x86_64> debug_call_with_fault_handler + 0x68
 3 ffffffff818ba500 (+  96) ffffffff800a3acb   <kernel_x86_64> invoke_debugger_command + 0xcf
 4 ffffffff818ba560 (+  80) ffffffff800a3c0c   <kernel_x86_64> invoke_pipe_segment(debugger_command_pipe*, int, char*) + 0x81
 5 ffffffff818ba5b0 (+  80) ffffffff800a3ced   <kernel_x86_64> invoke_debugger_command_pipe + 0xa0
 6 ffffffff818ba600 (+  80) ffffffff800a804d   <kernel_x86_64> ExpressionParser::_ParseCommandPipe(int&) + 0xdbf
 7 ffffffff818ba650 (+  96) ffffffff800ae234   <kernel_x86_64> ExpressionParser::EvaluateCommand(char const*, int&) + 0xba2
 8 ffffffff818ba6b0 (+ 240) ffffffff800af4b3   <kernel_x86_64> evaluate_debug_command + 0x99
 9 ffffffff818ba7a0 (+  96) ffffffff800a2132   <kernel_x86_64> kernel_debugger_loop(char const*, char const*, __va_list_tag*, int) + 0x2fd
10 ffffffff818ba800 (+  80) ffffffff800a22fa   <kernel_x86_64> kernel_debugger_internal(char const*, char const*, __va_list_tag*, int) + 0x132
11 ffffffff818ba850 (+ 240) ffffffff800a256e   <kernel_x86_64> panic + 0xc1
12 ffffffff818ba940 (+ 272) ffffffff8011c5c5   <kernel_x86_64> vm_page_fault + 0x15a
13 ffffffff818baa50 (+  64) ffffffff8013980c   <kernel_x86_64> x86_page_fault_exception + 0x1bb
14 ffffffff818baa90 (+ 536) ffffffff801326ef   <kernel_x86_64> int_bottom + 0x56
kernel iframe at 0xffffffff818baca8 (end = 0xffffffff818bad70)
 rax 0x0                   rbx 0xffffffff82007510    rcx 0xf6
 rdx 0xffffffff            rsi 0xffffffff82007558    rdi 0xffffffff82007558
 rbp 0xffffffff818bada0     r8 0xc6                   r9 0x80000009
 r10 0xc6                  r11 0x3246                r12 0xffffffff878c0fc8
 r13 0x0                   r14 0xffffffff82007548    r15 0x1
 rip 0xffffffff8010c968    rsp 0xffffffff818bad70 rflags 0x13282
 vector: 0xe, error code: 0x0
15 ffffffff818baca8 (+ 248) ffffffff8010c968   <kernel_x86_64> object_cache_alloc + 0x1a8
16 ffffffff818bada0 (+  64) ffffffff8010506f   <kernel_x86_64> block_alloc(unsigned long, unsigned long, unsigned int) + 0x83
17 ffffffff818bade0 (+  16) ffffffff80105383   <kernel_x86_64> malloc + 0x13
18 ffffffff818badf0 (+ 208) ffffffff8006c6c3   <kernel_x86_64> writev_port_etc + 0x41a
19 ffffffff818baec0 (+  96) ffffffff8006d044   <kernel_x86_64> _user_write_port_etc + 0xc7
20 ffffffff818baf20 (+  24) ffffffff80132995   <kernel_x86_64> x86_64_syscall_entry + 0xfb
user iframe at 0xffffffff818baf38 (end = 0xffffffff818bb000)
 rax 0xdc                  rbx 0x2108804ffe0         rcx 0x1719aa5fb24
 rdx 0x2108804ffe0         rsi 0x706a7070            rdi 0x77
 rbp 0x7f11ab23f510         r8 0x8                    r9 0x0
 r10 0xc6                  r11 0x3246                r12 0x77
 r13 0x0                   r14 0xc6                  r15 0x7f11ab23f630
 rip 0x1719aa5fb24         rsp 0x7f11ab23f508     rflags 0x3246
 vector: 0x63, error code: 0x0
21 ffffffff818baf38 (+139715983984088) 000001719aa5fb24   <libroot.so> _kern_write_port_etc + 0x0c
22 00007f11ab23f510 (+  48) 0000019b29eb6f67   <libbe.so> BMessage::_SendFlattenedMessage(void*, int, int, int, long) + 0x73
23 00007f11ab23f540 (+  16) 0000002aeb6ba1c9   <_APP_> MessageDeliverer::_SendMessage(MessageDeliverer::Message*, int, int) + 0x19
24 00007f11ab23f550 (+ 208) 0000002aeb6ba9bf   <_APP_> MessageDeliverer::DeliverMessage(void const*, int, MessagingTargetSet&, long) + 0x169
25 00007f11ab23f620 (+  64) 0000002aeb6bd7cc   <_APP_> MessagingService::DefaultSendCommandHandler::HandleMessagingCommand(unsigned int, void const*, int) + 0x48
26 00007f11ab23f660 (+  96) 0000002aeb6bcfc1   <_APP_> MessagingService::_CommandProcessor() + 0xbb
27 00007f11ab23f6c0 (+  16) 0000002aeb6bd0f5   <_APP_> MessagingService::_CommandProcessorEntry(void*) + 0x09
28 00007f11ab23f6d0 (+  32) 000001719aa5e988   <libroot.so> _thread_do_exit_work (nearest) + 0x72
29 00007f11ab23f6f0 (+   0) 00007f9cf7952260   <commpage> commpage_thread_exit + 0x00

[kallisti5]

If anyone is interested in debugging, you can access the machine right now :-)

spicec --host hinansho.net --port 5901

[waddlesplash]

Anyone seen this since?

[waddlesplash]

Apparently it does still occur; Diver got it in #15259.