Re: [RFC PATCH V3 12/16] x86/sev: Add a #HV exception handler

[Gupta, Pankaj]

On 2/3/2023 8:27 AM, Tianyu Lan wrote:
> On 1/23/2023 3:33 PM, Gupta, Pankaj wrote:
> > > + */
> > > +.macro idtentry_hv vector asmsym cfunc
> > > +SYM_CODE_START(\asmsym)
> > > +    UNWIND_HINT_IRET_REGS
> > > +    ASM_CLAC
> >
> > Did you get a chance to review the new instructions
> > added at the start similar to idtentry_vc and comments
> > added assuggested here?
> >
> > https://lore.kernel.org/lkml/16e50239-39b2-4fb4-5110-18f13ba197fe@xxxxxxx/
>
> Hi Pankaj:
>      Thanks for your reminder. Yes, CLD should be add after ASM_CLAC. 
> Will fix it.

Also it looks ENDBR also needs to be added before ASM_CLAC? as I also 
get this:

vmlinux.o: warning: objtool: asm_exc_hv_injection+0x0: 
UNWIND_HINT_IRET_REGS without ENDBR
vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from 
callable instruction with modified stack frame
vmlinux.o: warning: objtool: ibt_selftest+0x1e: return with modified 
stack frame
vmlinux.o: warning: objtool: def_idts+0x1d8: data relocation to !ENDBR: 
asm_exc_hv_injection+0x0

Thanks,
Pankaj