Re: [RFC 02/14] x86/apic: Initialize Secure AVIC APIC backing page

[Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>]

On 10/23/2024 10:06 PM, Borislav Petkov wrote:
> On Fri, Sep 13, 2024 at 05:06:53PM +0530, Neeraj Upadhyay wrote:
>> @@ -61,8 +65,30 @@ static void x2apic_savic_send_IPI_mask_allbutself(const struct cpumask *mask, in
>>  	__send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
>>  }
>>  
>> +static void x2apic_savic_setup(void)
>> +{
>> +	void *backing_page;
>> +	enum es_result ret;
>> +	unsigned long gpa;
>> +
>> +	if (this_cpu_read(savic_setup_done))
> 
> I'm sure you can get rid of that silly bool. Like check the apic_backing_page
> pointer instead and use that pointer to verify whether the per-CPU setup has
> been done successfully.
> 

Ok agree. In this patch version, APIC backing page allocation for all CPUs is done in
x2apic_savic_probe(). This is done to group the allocation together, so that these
backing pages are mapped using single 2M NPT and RMP entry.
I will move the APIC backing page setup to per-CPU setup (x2apic_savic_setup()) and
use that pointer to do the check.


- Neeraj