Re: [Qemu-devel] [PATCH v3 for-3.0] tests/libqtest: Improve kill_qemu()

[Thomas Huth <thuth@redhat.com>]

On 07/31/2018 12:08 AM, Eric Blake wrote:
> In kill_qemu() we have an assert that checks that the QEMU process
> didn't dump core:
>             assert(!WCOREDUMP(wstatus));
> 
> Unfortunately the WCOREDUMP macro here means the resulting message
> is not very easy to comprehend on at least some systems:
> 
> ahci-test: tests/libqtest.c:113: kill_qemu: Assertion `!(((__extension__ (((union { __typeof(wstatus) __in; int __i; }) { .__in = (wstatus) }).__i))) & 0x80)' failed.
> 
> and it doesn't identify what signal the process took.
> 
> Furthermore, we are NOT detecting EINTR (while EINTR shouldn't be
> happening if we didn't install signal handlers, it's still better
> to always be robust), and also want to log unexpected non-zero status
> that was not accompanied by a core dump.
> 
> Instead of using a raw assert, print the information in an
> easier to understand way:
> 
> /i386/ahci/sanity: tests/libqtest.c:119: kill_qemu() detected QEMU death with core dump from signal 11 (Segmentation fault)
> Aborted (core dumped)
> 
> (Of course, the really useful information would be why the QEMU
> process dumped core in the first place, but we don't have that
> by the time the test program has picked up the exit status.)
> 
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Eric Blake <eblake@redhat.com>

Reviewed-by: Thomas Huth <thuth@redhat.com>