Re: [Qemu-devel] [PULL 0/4] hmp queue

[Thomas Huth]

On 25.04.2017 15:13, Peter Maydell wrote:
> On 25 April 2017 at 11:41, Dr. David Alan Gilbert (git)
> <address@hidden> wrote:
>> From: "Dr. David Alan Gilbert" <address@hidden>
>>
>> The following changes since commit f4b5b021c847669b1c78050aea26fe9abceef6dd:
>>
>>   Merge remote-tracking branch 'remotes/cody/tags/block-pull-request' into 
>> staging (2017-04-25 09:21:54 +0100)
>>
>> are available in the git repository at:
>>
>>   git://github.com/dagrh/qemu.git tags/pull-hmp-20170425
>>
>> for you to fetch changes up to 1eb8e78dd1cd4e0b4170fd42f6d8882c867f334b:
>>
>>   tests: Add a tester for HMP commands (2017-04-25 11:26:52 +0100)
>>
>> ----------------------------------------------------------------
>> HMP pull with fixed test/strcmp case
>>
>> ----------------------------------------------------------------
> 
> test-hmp fails for me on OSX hosts:
> 
> TEST: tests/test-hmp... (pid=6008)
>   /aarch64/hmp/n810:
> qemu: qemu_mutex_lock: Invalid argument
> Broken pipe
> FAIL
> GTester: last random seed: R02Sd714920da46f8a0e37afec762c6ee23b
> (pid=6013)
>   /aarch64/hmp/tosa:
> qemu: qemu_mutex_lock: Invalid argument
> Broken pipe
> FAIL
> GTester: last random seed: R02Sf3025925b9db75bdfdd9f09cf3119ad5

What a bummer... does it only happen with aarch64 or also with the
other binaries?

> Can't do a backtrace, I'm afraid -- Apple's debugger doesn't seem
> to work if you're not root and the lack of X11 forwarding on the
> box I'm using remotely interacts really badly with qtest's
> desire to run qemu as a background process that it's hard to
> attach a debugger to. Something's probably not initializing
> a mutex, though -- Linux by default treats zeroes as a valid
> initialized mutex so it won't notice. You may be able to repro
> on Linux by using the Linux PTHREAD_MUTEX_ERRORCHECK_NP
> mutex attr, possibly.

I tried to set that attribute in qemu_mutex_init() (assuming that this
is what you meant), but it does not make a difference here on Linux -
the test always succeeds.

So another idea: Could you start the test in verbose mode like this:

V=2 QTEST_QEMU_BINARY=aarch64-softmmu/qemu-system-aarch64 tests/test-hmp

Maybe we get a hint which HMP command is causing the trouble here...

 Thomas