Re: [PATCH 1/4] x86/mce: Define 'SUCCOR' cpuid bit

Aravind Gopalakrishnan
2015-05-01T14:54:31Z

On 5/1/2015 5:25 AM, Borislav Petkov wrote:
> On Thu, Apr 30, 2015 at 09:49:22AM -0500, Aravind Gopalakrishnan wrote:
>> SUCCOR stands for S/W UnCorrectable error COntainment and Recovery.
>> It indicates support for data poisoning in HW and deferred error
>> interrupts.
>>
>>
>>
>> struct mce_vendor_flags {
>> __u64 overflow_recov : 1, /* cpuid_ebx(80000007) */
>> - __reserved_0 : 63;
>> + succor : 1,
> Please add that CPUID bit definition from the commit message here too so
> that we know what it means.

Will do.

Shall I beef up comment regarding 'overflow_recov' too?
Something like 'overflow recovery cpuid bit indicates that overflow
conditions are not fatal'
would provide a better indication of the usage of the bit IMHO.

>> case X86_VENDOR_AMD:
>> mce_amd_feature_init(c);
>> mce_flags.overflow_recov = cpuid_ebx(0x80000007) & 0x1;
>> + mce_flags.succor = (cpuid_ebx(0x80000007) & 0x2) ? 1 : 0;
> mce_flags.succor = !!(cpuid_ebx(0x80000007) & BIT(1));
>
> is a common way of assigning truth values from bits in the kernel.
>
> You can change the above one to use BIT(0) too, while at it, and
> vertically align the assignments.
>
>

Ok, Will do.

Thanks,
-Aravind.