On 11/22/2023 1:24 PM, Borislav Petkov wrote:
On Sat, Nov 18, 2023 at 01:32:30PM -0600, Yazen Ghannam wrote:
+void mce_setup_global(struct mce *m)
We usually call those things "common":
mce_setup_common().
+{
+ memset(m, 0, sizeof(struct mce));
+
+ m->cpuid = cpuid_eax(1);
+ m->cpuvendor = boot_cpu_data.x86_vendor;
+ m->mcgcap = __rdmsr(MSR_IA32_MCG_CAP);
+ /* need the internal __ version to avoid deadlocks */
+ m->time = __ktime_get_real_seconds();
+}
+
+void mce_setup_per_cpu(struct mce *m)
And call this
mce_setup_for_cpu(unsigned int cpu, struct mce *m);
so that it doesn't look like some per_cpu helper.
And yes, you should supply the CPU number as an argument. Because
otherwise, when you look at your next change:
+ mce_setup_global(&m);
+ m.cpu = m.extcpu = cpu;
+ mce_setup_per_cpu(&m);
This contains the "hidden" requirement that m.extcpu happens *always*
*before* the mce_setup_per_cpu() call and that is flaky and error prone.
So make that:
mce_setup_common(&m);
mce_setup_for_cpu(m.extcpu, &m);
and do m.cpu = m.extcpu = cpu inside the second function.
And then it JustWorks(tm) and you can't "forget" assigning m.extcpu and
there's no subtlety.
Ok?
Yep, understood. Thanks!
-Yazen
