Re: [PATCH 2/3] x86: Introduce new debug.c for debug register infrastructure

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 29/08/2023 3:10 pm, Jan Beulich wrote:
> On 29.08.2023 15:43, Andrew Cooper wrote:
>> Broken out of the subsequent patch for clarity.
>>
>> Add stub x86_adj_dr{6,7}_rsvd() functions which will be extended in the
>> following patch to fix bugs, and adjust debugreg.h to compile with a more
>> minimal set of includes.
>>
>> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
> Acked-by: Jan Beulich <jbeulich@suse.com>
> preferably with (nit) ...
>
>> --- a/xen/arch/x86/include/asm/debugreg.h
>> +++ b/xen/arch/x86/include/asm/debugreg.h
>> @@ -77,7 +77,18 @@
>>      asm volatile ( "mov %%db" #reg ",%0" : "=r" (__val) );  \
>>      __val;                                                  \
>>  })
>> +
>> +struct vcpu;
>>  long set_debugreg(struct vcpu *, unsigned int reg, unsigned long value);
>>  void activate_debugregs(const struct vcpu *);
>>  
>> +struct cpu_policy;
>> +
>> +/*
>> + * Architecturally dr6/7 are full GPR-width, but only the bottom 32 bits may
>> + * legally be non-zero.  We avoid avoid storing the upper bits when possible.
> ... one "avoid" dropped here.

Oops.  Will fix.

Thanks.

~Andrew