Re: [patch v2 1/2] x86,module: Detect VMX modules and disable Split-Lock-Detect

[Nadav Amit]

> On Apr 2, 2020, at 9:25 AM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> 
> 
> Learn to trim your replies already!
> 
> On Fri, Apr 03, 2020 at 12:20:08AM +0800, Xiaoyao Li wrote:
>> On 4/2/2020 11:23 PM, Peter Zijlstra wrote:
> 
>>> +bad_module:
>>> +	pr_warn("disabled due to VMX in module: %s\n", me->name);
>>> +	sld_state = sld_off;
>> 
>> shouldn't we remove the __ro_after_init of sld_state?
> 
> Oh, that's probably a good idea. I can't actually test this due to no
> hardware.

Just wondering, since I lack hardware as well: can the performance counter
LOCK_CYCLES.SPLIT_LOCK_UC_LOCK_DURATION be used to detect split-locks
similarly to SLD (although it would be after the split-lock event)?