Re: [PATCH] nvmm: Fix support for stable version

[nia]

Ping? It would be very nice if this could make it into 6.2
so we don't have to continue patching around this.

On Tue, Nov 02, 2021 at 10:12:28AM +0100, Kamil Rytarowski wrote:
> Reviewed-by: Kamil Rytarowski <kamil@netbsd.org>
> 
> Paolo, could you please merge it?
> 
> On 13.10.2021 15:54, nia wrote:
> > NVMM user version 1 is the version being shipped with netbsd-9,
> > which is the most recent stable branch of NetBSD. This makes it
> > possible to use the NVMM accelerator on the most recent NetBSD
> > release, 9.2, which lacks nvmm_cpu_stop.
> > 
> > (CC'ing maintainers)
> > 
> > Signed-off-by: Nia Alarie <nia@NetBSD.org>
> > ---
> >  meson.build                 |  4 +---
> >  target/i386/nvmm/nvmm-all.c | 10 ++++++++++
> >  2 files changed, 11 insertions(+), 3 deletions(-)
> > 
> > diff --git a/meson.build b/meson.build
> > index 15ef4d3c41..6e4d9b919a 100644
> > --- a/meson.build
> > +++ b/meson.build
> > @@ -244,9 +244,7 @@ if not get_option('hax').disabled()
> >    endif
> >  endif
> >  if targetos == 'netbsd'
> > -  if cc.has_header_symbol('nvmm.h', 'nvmm_cpu_stop', required: 
> > get_option('nvmm'))
> > -    nvmm = cc.find_library('nvmm', required: get_option('nvmm'))
> > -  endif
> > +  nvmm = cc.find_library('nvmm', required: get_option('nvmm'))
> >    if nvmm.found()
> >      accelerators += 'CONFIG_NVMM'
> >    endif
> > diff --git a/target/i386/nvmm/nvmm-all.c b/target/i386/nvmm/nvmm-all.c
> > index a488b00e90..4a10412427 100644
> > --- a/target/i386/nvmm/nvmm-all.c
> > +++ b/target/i386/nvmm/nvmm-all.c
> > @@ -750,7 +750,11 @@ nvmm_vcpu_loop(CPUState *cpu)
> >          nvmm_vcpu_pre_run(cpu);
> >  
> >          if (qatomic_read(&cpu->exit_request)) {
> > +#if NVMM_USER_VERSION >= 2
> >              nvmm_vcpu_stop(vcpu);
> > +#else
> > +            qemu_cpu_kick_self();
> > +#endif
> >          }
> >  
> >          /* Read exit_request before the kernel reads the immediate exit 
> > flag */
> > @@ -767,6 +771,7 @@ nvmm_vcpu_loop(CPUState *cpu)
> >          switch (exit->reason) {
> >          case NVMM_VCPU_EXIT_NONE:
> >              break;
> > +#if NVMM_USER_VERSION >= 2
> >          case NVMM_VCPU_EXIT_STOPPED:
> >              /*
> >               * The kernel cleared the immediate exit flag; 
> > cpu->exit_request
> > @@ -775,6 +780,7 @@ nvmm_vcpu_loop(CPUState *cpu)
> >              smp_wmb();
> >              qcpu->stop = true;
> >              break;
> > +#endif
> >          case NVMM_VCPU_EXIT_MEMORY:
> >              ret = nvmm_handle_mem(mach, vcpu);
> >              break;
> > @@ -888,8 +894,12 @@ nvmm_ipi_signal(int sigcpu)
> >  {
> >      if (current_cpu) {
> >          struct qemu_vcpu *qcpu = get_qemu_vcpu(current_cpu);
> > +#if NVMM_USER_VERSION >= 2
> >          struct nvmm_vcpu *vcpu = &qcpu->vcpu;
> >          nvmm_vcpu_stop(vcpu);
> > +#else
> > +        qcpu->stop = true;
> > +#endif
> >      }
> >  }
> >  
> > 
>