Re: [PATCH v2] xen/pv: Fix a boot up hang revealed by int3 self test

[Zhenzhong Duan]

On 2019/7/12 21:09, Peter Zijlstra wrote:
> On Fri, Jul 12, 2019 at 09:04:22PM +0800, Zhenzhong Duan wrote:
> > On 2019/7/12 20:06, Peter Zijlstra wrote:
> > > On Thu, Jul 11, 2019 at 04:15:21PM +0800, Zhenzhong Duan wrote:
> > > > diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
> > > > index 4722ba2..2138d69 100644
> > > > --- a/arch/x86/xen/enlighten_pv.c
> > > > +++ b/arch/x86/xen/enlighten_pv.c
> > > > @@ -596,7 +596,7 @@ struct trap_array_entry {
> > > >    static struct trap_array_entry trap_array[] = {
> > > >    	{ debug,                       xen_xendebug,                    true },
> > > > -	{ int3,                        xen_xenint3,                     true },
> > > > +	{ int3,                        xen_int3,                        true },
> > > >    	{ double_fault,                xen_double_fault,                true },
> > > >    #ifdef CONFIG_X86_MCE
> > > >    	{ machine_check,               xen_machine_check,               true },
> > > I'm confused on the purpose of trap_array[], could you elucidate me?
> > Used to replace trap handler addresses by Xen specific ones and sanity check
> >
> > if there's an unexpected IST-using fault handler.
> git grep xen_int3, failed me. Where does that symbol come from?

Generated by "xen_pv_trap int3" in arch/x86/xen/xen-asm_64.S

Zhenzhong