Re: [PATCH v1 07/17] xen/riscv: introduce vCPU AIA initialization

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 8/13/26 11:47 AM, Jan Beulich wrote:
> On 13.08.2026 11:24, Baptiste Le Duc wrote:
> > > --- a/xen/arch/riscv/aia.c
> > > +++ b/xen/arch/riscv/aia.c
> > > @@ -14,6 +14,7 @@
> > >   #include <asm/cpufeature.h>
> > >   #include <asm/csr.h>
> > >   #include <asm/current.h>
> > > +#include <asm/imsic.h>
> > >   
> > >   struct vgein_ctrl {
> > >       unsigned long bmp;
> > > @@ -36,6 +37,35 @@ bool aia_usable(void)
> > >       return _aia_usable;
> > >   }
> > >   
> > > +void vcpu_aia_init(struct vcpu *v)
> > > +{
> > > +    unsigned int new_vsfile_id;
> > > +    int rc;
> > > +
> > > +    if ( !aia_usable() )
> > > +        return;
> > > +
> > > +    new_vsfile_id = vgein_assign(v);
> > > +
> > > +    /*
> > > +     * vgein_assign() returns 0 when no free h/w guest interrupt file is
> > > +     * available (including GEILEN == 0); imsic_map_guest_file() maps nothing
> > > +     * in that case.
> > > +     */
> > > +    rc = imsic_map_guest_file(v, new_vsfile_id);
> > > +    if ( rc )
> > > +    {
> > > +        /* Can't continue w/o correctly mapped IMSIC interrupt file */
> > > +        domain_crash(v->domain);
> > The vgein id assigned a few lines up is not released here. The domain is dying
> > anyway, but the guest interrupt file stays marked in use on that pCPU forever,
> > since nothing else ever calls vgein_release(). A vgein_release(v,
> > new_vsfile_id) before the domain_crash() would fix it.
> Instead of (or in addition to) doing that here, wouldn't releasing better be 
> part
> of the normal cleanup path? Whether "instead of" or "in addition to" depends on
> the implications of deferring the release. But to guarantee no leak, domain
> cleanup will want to either do the release, or have an explicit check that is 
> was
> done.
I think vgein_release() should be here, as when the IMSIC software 
interrupt file is supported, it will mean that domain_crash() can 
generally be dropped (there is no need to call imsic_map_guest_file() 
for s/w IMSIC interrupt file) and the vCPU can use the software 
interrupt file instead of killing the domain.
~ Oleksii