Messages in this thread | | | Subject | Re: [PATCH] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled | From | Jürgen Groß <> | Date | Tue, 26 Jan 2021 06:12:42 +0100 |
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On 25.01.21 18:26, Andrew Cooper wrote: > On 25/01/2021 14:00, Juergen Gross wrote: >> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c >> index 4409306364dc..82948251f57b 100644 >> --- a/arch/x86/xen/enlighten_pv.c >> +++ b/arch/x86/xen/enlighten_pv.c >> @@ -583,6 +583,14 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug) >> exc_debug(regs); >> } >> >> +#ifdef CONFIG_AMD_MEM_ENCRYPT >> +DEFINE_IDTENTRY_RAW(xenpv_exc_vmm_communication) >> +{ >> + /* This should never happen and there is no way to handle it. */ >> + panic("X86_TRAP_VC in Xen PV mode."); > > Honestly, exactly the same is true of #VE, #HV and #SX. > > What we do in the hypervisor is wire up one handler for all unknown > exceptions (to avoid potential future #DF issues) leading to a panic. > Wouldn't it be better to do this unconditionally, especially as #GP/#NP > doesn't work for PV guests for unregistered callbacks, rather than > fixing up piecewise like this?
I agree it would be better to have a "catch all unknown" handler.
I'll have a try how this would look like.
Juergen
[unhandled content-type:application/pgp-keys][unhandled content-type:application/pgp-signature] | |