Re: [RFC][PATCH 05/10] x86/mm: do not auto-massage page protections

[Dave Hansen]

On 02/22/2018 01:46 PM, Nadav Amit wrote:
>>
>> +static inline pgprotval_t check_pgprot(pgprot_t pgprot)
>> +{
>> +	pgprotval_t massaged_val = massage_pgprot(pgprot);
>> +
>> +	WARN_ONCE(pgprot_val(pgprot) != massaged_val,
>> +		  "attempted to set unsupported pgprot: %016lx "
>> +		  "bits: %016lx supported: %016lx\n",
>> +		  pgprot_val(pgprot),
>> +		  pgprot_val(pgprot) ^ massaged_val,
>> +		  __supported_pte_mask);
> Perhaps use VM_WARN_ONCE instead to avoid any overhead on production
> systems?

Sounds sane enough.  I'll change it.