Re: Meltdown workaround enabled?

On Tue, Mar 13, 2018 at 2:29 AM, Mike Larkin <mlarkin@azathoth.net> wrote:
> On Sun, Mar 11, 2018 at 04:33:49PM -0500, Brian Camp wrote:
>> I have two systems running 6.2-stable with the meltdown syspatch
>> installed. I noticed that while one of them lists "MELTDOWN" in the
>> CPU flags, the other does not. The one that does not has a Celeron
>> J3455, which Intel lists as affected by meltdown.
>>
>> Does the absence of the MELTDOWN flag mean that the workaround isn't
>> functioning on this machine? Dmesg below.
>>
>>
>> Thanks
>>
>> -Brian
>>
>
> Odd. Two of us have looked at the detection code again and we can't see any
> issues. Can you please do the following to help diagnose?
>
> 1. install the "cpuid" port package?
>
> pkg_add cpuid
>
> 2. send the output of:
>
> cpuid 0x0
> cpuid 0x7
>
> On each of the two machines? (Make sure to say which is the working one
> and which is the one where meltdown isn't properly being detected).
>
> Thanks.
>
> -ml

Sure thing.

Working (i5-4690) -

bcamp@z97x-sli:~ (OpenBSD 6.2)
$ cpuid 0x0
eax = 0x0000000d 13 "????"
ebx = 0x756e6547 1970169159 "Genu"
ecx = 0x6c65746e 1818588270 "ntel"
edx = 0x49656e69 1231384169 "ineI"
bcamp@z97x-sli:~ (OpenBSD 6.2)
$ cpuid 0x7
eax = 0x00000000 0 "????"
ebx = 0x000027ab 10155 "?'??"
ecx = 0x00000000 0 "????"
edx = 0x00000000 0 "????"
bcamp@z97x-sli:~ (OpenBSD 6.2)
$

Non-working (Celeron J3455) -

bcamp@nuc6cayh:~ (OpenBSD 6.2)
$ cpuid 0x0
eax = 0x00000015 21 "????"
ebx = 0x756e6547 1970169159 "Genu"
ecx = 0x6c65746e 1818588270 "ntel"
edx = 0x49656e69 1231384169 "ineI"
bcamp@nuc6cayh:~ (OpenBSD 6.2)
$ cpuid 0x7
eax = 0x00000000 0 "????"
ebx = 0x2294e283 580182659 "???""
ecx = 0x00000000 0 "????"
edx = 0x2c000000 738197504 "???,"
bcamp@nuc6cayh:~ (OpenBSD 6.2)
$


-Brian