RE: [PATCH v12 10/18] x86/fsgsbase/64: Enable FSGSBASE instructions in helper functions

[Thomas Gleixner]

David Laight <David.Laight@xxxxxxxxxx> writes:
> From: Sasha Levin
>> >> +		native_swapgs();
>> >> +		gsbase = rdgsbase();
>> >> +		native_swapgs();
>
> Does local_irq_save() even do anything useful here.
> You need to actually execute CLI, not just set a
> flag that indicates interrupts shouldn't happen.
> (Which is what I think local_irq_save() might do.)

  local_irq_save()
    raw_local_irq_save()
      arch_local_irq_save()
        arch_local_irq_disable()
          native_irq_disable()
            asm("CLI")

> You also (probably) need to disable NMIs.

The NMI entry can deal with that obviously.

Thanks,

        tglx