Re: x86/mce: suspicious RCU usage in 4.13.4

[Luck, Tony]

On Wed, Nov 01, 2017 at 05:47:54PM +0100, Borislav Petkov wrote:
> On Wed, Nov 01, 2017 at 07:56:20AM -0700, Laura Abbott wrote:
> > Did these get queued up somewhere? I know last week was OSSEU/Ksummit
> > so people may still be playing catch-up.
> 
> Ah, thanks for the reminder.
> 
> /me goes and dusts it off.
> 
> Ok, here it is, injecting some MCEs in a guest seems to work fine,
> mcelog logs them.
> 
> Tony?

Yup. I did a bit more testing on bare metal with injection:

1) Just one error
	Worked
2) "kill -STOP `pgrep mcelog`" ; inject 5 errors ; "kill -CONT `pgrep mcelog`"
	Worked (all five errors reported correctly)
3) "kill -STOP `pgrep mcelog`" ; inject 35 errors ; "kill -CONT `pgrep mcelog`"
	mcelog reported Warning: MCE buffer is overflowed.
	First 32 (MCE_LOG_LEN) errors reported correctly.

Reviewed-and-tested-by: Tony Luck <tony.luck@xxxxxxxxx>

-Tony