[Qemu-devel] make check breakage on 32 bit hosts

[Qemu-devel] make check breakage on 32 bit hosts

[Blue Swirl]

I get this on i386 chroot for make check:

GTESTER tests/test-qmp-output-visitor
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S559792e7c8d0762d9a2ee153fba8896c
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S525fa86060d45f6d4299653ffb5dd904
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S7ae707c4805ddbba77d7d41893ebf867
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:633:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S38f6b432c1499bbd11f431efcf631a46

The same happens on an ARM host:

GTESTER tests/test-qmp-output-visitor
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02Sb86519e4b02345f084b2b23eb7deb24b
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S5207cd8bf70d0fd158dd531ad3b3b127
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S1805df984bcb85d0f11bc0d66e94630e
**
ERROR:/src/qemu/tests/test-qmp-output-visitor.c:633:check_native_list:
assertion failed: (tmp)
GTester: last random seed: R02S9a6b4dd63a8e370a262925d5b130a79b

Re: [Qemu-devel] make check breakage on 32 bit hosts

[mdroth]

On Sun, May 26, 2013 at 12:00:57PM +0000, Blue Swirl wrote:
> I get this on i386 chroot for make check:
> 
> GTESTER tests/test-qmp-output-visitor
> **
> ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
> assertion failed: (tmp)
> GTester: last random seed: R02S559792e7c8d0762d9a2ee153fba8896c
> **

Tests case looks correct, problem seems to be that we cast list node to
GenericList, which expects the 'value' field to be a pointer type. With
native lists types these are in some cases non-pointer types, like
intList, where 'value' is an int64_t. On 32-bit archs this cast leads to
use uses incorrect offset when trying to traverse the list.

Don't see a way to fix this outside of making the code generators do
a bit of massaging for these cases rather than a cast. Looking at it
now, but might not be able to send a patch till later.

Re: [Qemu-devel] make check breakage on 32 bit hosts

[mdroth]

On Sun, May 26, 2013 at 10:26:48AM -0500, mdroth wrote:
> On Sun, May 26, 2013 at 12:00:57PM +0000, Blue Swirl wrote:
> > I get this on i386 chroot for make check:
> > 
> > GTESTER tests/test-qmp-output-visitor
> > **
> > ERROR:/src/qemu/tests/test-qmp-output-visitor.c:595:check_native_list:
> > assertion failed: (tmp)
> > GTester: last random seed: R02S559792e7c8d0762d9a2ee153fba8896c
> > **
> 
> Tests case looks correct, problem seems to be that we cast list node to
> GenericList, which expects the 'value' field to be a pointer type. With
> native lists types these are in some cases non-pointer types, like
> intList, where 'value' is an int64_t. On 32-bit archs this cast leads to
> use uses incorrect offset when trying to traverse the list.
> 
> Don't see a way to fix this outside of making the code generators do
> a bit of massaging for these cases rather than a cast. Looking at it
> now, but might not be able to send a patch till later.

Patch sent:

http://article.gmane.org/gmane.comp.emulators.qemu/213202

Teaching code generators to be smarter didn't work out so well
since visitor implementations allocate storage of list types based
on GenericList, so ended up relying on padding to 64-bit instead.