Re: [Qemu-devel] 2 MiB alignment in qemu_vmalloc()

[Stefan Weil]

Am 12.10.2011 22:47, schrieb Alexander Graf:
> Well, yes, my point is that it's a bug in valgrind that should be 
> fixed. I don't think we should special-case QEMU because of bugs in 
> debugging software :)
>
> Alex

Yes, the valgrind bug should be fixed. I don't know why it isn't,
but that's not the point:

Valgrind is very valuable for finding certain kinds of bugs in QEMU
which we want to find and fix (I hope we agree on this).
Therefore developers should be able to use it.

Today, they cannot use Valgrind with QEMU out-of-the box,
because they get an assertion. Some developers will stop here.
Others will ask Google, look in Valgrind's code and spend some
time to find and fix the problem before they start using
Valgrind to find QEMU bugs.

They could have spent their time better.

I can try to make QEMU more useable with Valgrind by changing
the QEMU code (which was Valgrind compatible up to Avi's change).

I cannot change the Valgrind code, and even if I could, it would
take a lot of time until all Linux distributions would include a
fixed Valgrind :-(

If all existing gdb versions did not work with QEMU,
but there were a simple QEMU change which made them work,
what would you do?

Cheers,
Stefan