Re: [Xen-devel] [PATCH 6/7] xen/arm: vsmc: The function identifier is always 32-bit

[Stefano Stabellini <sstabellini@kernel.org>]

On Fri, 26 Jul 2019, Volodymyr Babchuk wrote:
> Julien Grall writes:
> 
> > On Arm64, the SMCCC function identifier is always stored in the first 32-bit
> > of x0 register. The rest of the bits are not defined and should be
> > ignored.
> >
> > This means the variable funcid should be an uint32_t rather than
> > register_t.
> >
> > Signed-off-by: Julien Grall <julien.grall@arm.com>
> Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

> > ---
> >  xen/arch/arm/vsmc.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/xen/arch/arm/vsmc.c b/xen/arch/arm/vsmc.c
> > index f8e350311d..a36db15fff 100644
> > --- a/xen/arch/arm/vsmc.c
> > +++ b/xen/arch/arm/vsmc.c
> > @@ -220,7 +220,7 @@ static bool vsmccc_handle_call(struct cpu_user_regs *regs)
> >  {
> >      bool handled = false;
> >      const union hsr hsr = { .bits = regs->hsr };
> > -    register_t funcid = get_user_reg(regs, 0);
> > +    uint32_t funcid = get_user_reg(regs, 0);
> >  
> >      /*
> >       * Check immediate value for HVC32, HVC64 and SMC64.
> > @@ -286,7 +286,7 @@ static bool vsmccc_handle_call(struct cpu_user_regs *regs)
> >  
> >      if ( !handled )
> >      {
> > -        gprintk(XENLOG_INFO, "Unhandled SMC/HVC: %08"PRIregister"\n", funcid);
> > +        gprintk(XENLOG_INFO, "Unhandled SMC/HVC: %#x\n", funcid);
> >  
> >          /* Inform caller that function is not supported. */
> >          set_user_reg(regs, 0, ARM_SMCCC_ERR_UNKNOWN_FUNCTION);
> 
> 
> -- 
> Volodymyr Babchuk at EPAM

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel