Re: [Qemu-devel] RDMA wrongly detected as being supported on FreeBSD

[Marcel Apfelbaum]

Hi,

On 08/06/2018 11:51 AM, Thomas Huth wrote:
> On 07/28/2018 05:50 AM, Rebecca Cran wrote:
> > On 7/25/18 5:14 AM, Thomas Huth wrote:
> >
> > > Note that the error has been reported to happen on FreeBSD - so I doubt
> > > that this <linux/types.h> header should be here.
> > >
> > > Anyway, our include/standard-headers/linux/types.h is also empty ... so
> > > could you try whether it compiles if you simply remove this #include
> > > line, Rebecca?
> >
> > Sorry for the delay, I'm just getting back to this. Removing the include
> > causes it to fail later on, with:
> >
> > /home/bcran/workspace/qemu/hw/rdma/vmw/pvrdma_cmd.c:60:17: warning:
> > implicit declaration of function 'mremap' is invalid in C99
> > [-Wimplicit-function-declaration]
> >      host_virt = mremap(curr_page, 0, length, MREMAP_MAYMOVE);
> OK, thanks for checking. According to
>
>   https://www.freebsd.org/cgi/man.cgi?query=mremap&manpath=NetBSD+5.0
>
> that syscall should also be available on FreeBSD. So could you please do
> one more test and see whether it works when you add the following line
> somewhere at the beginning of the file:
>
>    #include <sys/mman.h>

It took some time, but I finally have a FreeBSD VM with RDMA enabled.

My findings:
- The RDMA libraries are there, so the flag  "RDMA"=yes is set correctly.
- include of <linux/types.h> is not needed, I will remove it.
- In FreeBSD mremap is not implemented in all configurations, it depends
  on some SANITIZER_LINUX flag (Linux emulation?), I think;
  so pvrdma cannot be compiled.  I think we should have a different 
QEMU configuration
  flag --enable-pvrdma that will specifically check it is not a "bsd" 
platform.
  I'll send a patch for that too.

Thanks,
Marcel


>   Thanks,
>    Thomas