Re: [Qemu-devel] [PATCH v2] target-sh4: add atomic tas

[Paolo Bonzini]

On 04/11/2016 11:00, John Paul Adrian Glaubitz wrote:
> On 11/04/2016 10:53 AM, Laurent Vivier wrote:
>> I think it's more likely a linux-user bug than a target-sh4 bug.
>>
>> As you report in a mail to me in February, "do_futex()" must be
>> protected against parallel execution for some futex commands.
> 
> FWIW, it works fine on qemu-user-armel last time I tested. I could
> build GHC completely on qemu-user for armel without any issues.
> 
> Btw, if anyone wants to test themselves:
> 
> $ wget http://users.physik.fu-berlin.de/~glaubitz/sid-sh4-sbuild-ghc.tgz
> $ tar xf sid-sh4-sbuild-ghc.tgz
> (compile qemu with --target-list=sh4-linux-user --static)
> $ cp -av qemu-sh4 sid-sh4-sbuild-ghc/usr/bin/qemu-sh4-static
> $ chroot sid-sh4-sbuild-ghc
> (in chroot):
> $ cd /root/ghc-7.8.4/utils/ghc-pwd
> $ ghc Main.hs

If Haskell is compiled to use the "negative sp" trick that Richard
mentioned, it would rely on the SH machine being uniprocessor.  Try
running chroot with "taskset -c 0".

Paolo