Re: [Qemu-devel] tpm-tis-test and tpm-crb-test crash on OSX

[Marc-André Lureau]

Hi

On Fri, Mar 16, 2018 at 3:08 PM, Stefan Berger
<address@hidden> wrote:
> On 03/16/2018 09:45 AM, Stefan Berger wrote:
>>
>> On 03/16/2018 09:41 AM, Marc-André Lureau wrote:
>>>
>>> Hi
>>>
>>> On Fri, Mar 16, 2018 at 2:37 PM, Marc-André Lureau
>>> <address@hidden> wrote:
>>>>
>>>> Hi
>>>>
>>>> On Fri, Mar 16, 2018 at 2:27 PM, Daniel P. Berrangé
>>>> <address@hidden> wrote:
>>>>>
>>>>> On Fri, Mar 16, 2018 at 01:24:53PM +0000, Peter Maydell wrote:
>>>>>>
>>>>>> On 16 March 2018 at 13:12, Peter Maydell <address@hidden>
>>>>>> wrote:
>>>>>>>
>>>>>>> On OSX host, I noticed that tpm-tis-test and tpm-crb-test
>>>>>>> both crash on OSX, hitting an error_abort case:
>>>>>>>
>>>>>>> (lldb) run
>>>>>>> Process 65115 launched:
>>>>>>> '/Users/pm215/src/qemu-for-merges/build/all/tests/tpm-tis-test'
>>>>>>> (x86_64)
>>>>>>> /i386/tpm-tis/test_check_localities: OK
>>>>>>> /i386/tpm-tis/test_check_access_reg: OK
>>>>>>> /i386/tpm-tis/test_check_access_reg_seize: OK
>>>>>>> /i386/tpm-tis/test_check_access_reg_release: OK
>>>>>>> /i386/tpm-tis/test_check_transmit: OK
>>>>>>> Unexpected error in qio_channel_socket_readv() at
>>>>>>> /Users/pm215/src/qemu-for-merges/io/channel-socket.c:494:
>>>>>>> Unable to read from socket: Bad file descriptor
>>>>>>>
>>>>>>> Here's a backtrace from tpm-tis-test:
>>>>>>
>>>>>> Dan suggested a race condition, which prompted me to get an
>>>>>> all-threads backtrace:
>>>>>>
>>>>>>    thread #1: tid = 0xb50f19, 0x00007fff7eb97502
>>>>>> libsystem_kernel.dylib`__wait4 + 10, queue = 'com.apple.main-thread'
>>>>>>      frame #0: 0x00007fff7eb97502 libsystem_kernel.dylib`__wait4 + 10
>>>>>>      frame #1: 0x000000010001b303 tpm-tis-test`qtest_quit [inlined]
>>>>>> kill_qemu(s=<unavailable>) + 99 at libqtest.c:107
>>>>>>      frame #2: 0x000000010001b2df
>>>>>> tpm-tis-test`qtest_quit(s=0x0000000100404c60) + 63 at libqtest.c:280
>>>>>>      frame #3: 0x0000000100001bd1 tpm-tis-test`main [inlined]
>>>>>> qtest_end
>>>>>> + 9 at libqtest.h:555
>>>>>>      frame #4: 0x0000000100001bc8
>>>>>> tpm-tis-test`main(argc=<unavailable>,
>>>>>> argv=<unavailable>) + 520 at tpm-tis-test.c:477
>>>>>>      frame #5: 0x00007fff7ea47115 libdyld.dylib`start + 1
>>>>>>      frame #6: 0x00007fff7ea47115 libdyld.dylib`start + 1
>>>>>>
>>>>>>    thread #3: tid = 0xb50f4a, 0x00007fff7eb977d2
>>>>>> libsystem_kernel.dylib`close + 10
>>>>>>      frame #0: 0x00007fff7eb977d2 libsystem_kernel.dylib`close + 10
>>>>>>      frame #1: 0x0000000100007def
>>>>>> tpm-tis-test`qio_channel_socket_close(ioc=<unavailable>,
>>>>>> errp=0x000000010006c930) + 63 at channel-socket.c:693
>>>>>>      frame #2: 0x00000001000039f9
>>>>>> tpm-tis-test`tpm_emu_ctrl_thread(data=0x00007ffeefbff0e8) + 713 at
>>>>>> tpm-emu.c:128
>>>>>>      frame #3: 0x00000001001b2ec0
>>>>>> libglib-2.0.0.dylib`g_thread_create_proxy + 191
>>>>>>      frame #4: 0x00007fff7ecd26c1
>>>>>> libsystem_pthread.dylib`_pthread_body + 340
>>>>>>      frame #5: 0x00007fff7ecd256d
>>>>>> libsystem_pthread.dylib`_pthread_start + 377
>>>>>>      frame #6: 0x00007fff7ecd1c5d libsystem_pthread.dylib`thread_start
>>>>>> + 13
>>>>>>
>>>>>> * thread #2: tid = 0xb50f50, 0x00007fff7eb96e3e
>>>>>> libsystem_kernel.dylib`__pthread_kill + 10
>>>>>>    * frame #0: 0x00007fff7eb96e3e
>>>>>> libsystem_kernel.dylib`__pthread_kill + 10
>>>>>>      frame #1: 0x00007fff7ecd5150 libsystem_pthread.dylib`pthread_kill
>>>>>> + 333
>>>>>>      frame #2: 0x00007fff7eaf3312 libsystem_c.dylib`abort + 127
>>>>>>      frame #3: 0x0000000100043431 tpm-tis-test`error_setv [inlined]
>>>>>> error_handle_fatal(errp=<unavailable>) + 43 at error.c:38
>>>>>>      frame #4: 0x0000000100043406
>>>>>> tpm-tis-test`error_setv(errp=<unavailable>, src=<unavailable>,
>>>>>> line=<unavailable>, func=<unavailable>,
>>>>>> err_class=ERROR_CLASS_GENERIC_ERROR, fmt=<unavailable>,
>>>>>> ap=<unavailable>, suffix=<unavailable>) + 246 at error.c:71
>>>>>>      frame #5: 0x00000001000435db
>>>>>> tpm-tis-test`error_setg_errno_internal(errp=0x000000010006c930,
>>>>>> src="/Users/pm215/src/qemu-for-merges/io/channel-socket.c", line=494,
>>>>>> func="qio_channel_socket_readv", os_errno=<unavailable>, fmt="Unable
>>>>>> to read from socket") + 219 at error.c:111
>>>>>>      frame #6: 0x0000000100007ba5
>>>>>> tpm-tis-test`qio_channel_socket_readv(ioc=<unavailable>,
>>>>>> iov=<unavailable>, niov=<unavailable>, fds=0x0000000000000000,
>>>>>> nfds=0x0000000000000000, errp=0x000000010006c930) + 341 at
>>>>>> channel-socket.c:493
>>>>>>      frame #7: 0x0000000100004717 tpm-tis-test`qio_channel_read
>>>>>> [inlined] qio_channel_readv_full(ioc=0x00000001007006b0,
>>>>>> iov=<unavailable>, niov=1, fds=<unavailable>, nfds=<unavailable>,
>>>>>> errp=0x000000010006c930) + 62 at channel.c:65
>>>>>>      frame #8: 0x00000001000046d9
>>>>>> tpm-tis-test`qio_channel_read(ioc=0x00000001007006b0,
>>>>>> buf=<unavailable>, buflen=<unavailable>, errp=<unavailable>) + 41 at
>>>>>> channel.c:216
>>>>>>      frame #9: 0x0000000100003dd1
>>>>>> tpm-tis-test`tpm_emu_tpm_thread(data=0x00007ffeefbff0e8) + 241 at
>>>>>> tpm-emu.c:41
>>>>>>      frame #10: 0x00000001001b2ec0
>>>>>> libglib-2.0.0.dylib`g_thread_create_proxy + 191
>>>>>>      frame #11: 0x00007fff7ecd26c1
>>>>>> libsystem_pthread.dylib`_pthread_body + 340
>>>>>>      frame #12: 0x00007fff7ecd256d
>>>>>> libsystem_pthread.dylib`_pthread_start + 377
>>>>>>      frame #13: 0x00007fff7ecd1c5d
>>>>>> libsystem_pthread.dylib`thread_start + 13
>>>>>>
>>>>>>
>>>>>> My guess is that the problem here is that the tpm_emu_ctrl_thread
>>>>>> (thread 3) is
>>>>>> forcibly closing the channel, which causes the tpm_emu_thread (thread
>>>>>> 2)
>>>>>> to abort because its read returned an error.
>>>>>
>>>>> At least the tpm_emu_tpm_thread() there is only something in the test
>>>>> suite, so the real system emulator code isn't at risk of crashing.
>>>>>
>>>>> Feels like the thread simply should *not* use error_abort, and instead
>>>>> have a more graceful way to exit when the socket closes
>>>>>
>>>> The code expects the read() to return 0 on disconnect, not an error.
>>>> Apparently this works on !osx. Should we adapt qio-channel-socket to
>>>> return 0 in this case on osx too?
>>>
>>> Oh I see, it calls close() on the same end, that's not correct. I
>>> wonder if shutdown would be better. Other suggestions?
>>>
>> We could send the thread a special message, like 0xff ff ff ff, and that
>> terminates it...
>
>
> ... wrong end of socket, so doesn't work. Other way would be to pass a pipe
> to the TPM emulator thread and have it poll on the pipefd and the channelfd
> and terminate upon pipefd reception...
>

Or close the other end on tpm_emulator_shutdown(), I am trying this
approach now.



-- 
Marc-André Lureau