Re: [PATCH 5/5] x86: don't build unused entry code when !PV32

[Jan Beulich <jbeulich@xxxxxxxx>]

On 01.04.2021 16:31, Andrew Cooper wrote:
> On 25/11/2020 08:51, Jan Beulich wrote:
>> @@ -102,19 +102,21 @@ void __dummy__(void)
>>      BLANK();
>>  #endif
>>  
>> -#ifdef CONFIG_PV
>> +#ifdef CONFIG_PV32
>>      OFFSET(DOMAIN_is_32bit_pv, struct domain, arch.pv.is_32bit);
> 
> Even if PV32 is compiled out, the is_32bit field still exists, and is
> still necessary for crash analysis.  XCA parses this offset information
> as part of dissecting /proc/vmcore.
> 
> It's one single bool in a fixed size allocation which we've got plenty
> of room in.  It can and should stay to avoid impacting the existing
> diagnostic tools.

I'm afraid I don't understand at all: I'm not removing the field.
All I'm removing is the entry for it in asm-offsets.h. I'm also
unaware that the offset information gets added anywhere in the
binary, except encoded in instructions. If a tool needs to know
the offset, it ought to parse debug info?

Jan