freebsd stable - Feb 2018 - stable/11 r329462 - Meltdown/Spectre MFC questions

On Sun, Feb 18, 2018 at 05:04:55PM +0100, David Marec
wrote:
> On 17.02.2018 20:47, Jeremy Chadwick wrote:
> > hw.ibrs_disable
> >    - Description: Disable Indirect Branch Restricted Speculation
> >    - Loader tunable and sysctl tunable (read-write)
> >    - Integer
> >    - Default value: unsure.  Variable declaration has 1 but
> >      SYSCTL_PROC() macro has 0.
> > 
> 
> 
> Strange thing is that tweaking `hw.ibrs_disable` has no effect on
> `hw.ibrs_active` on my side.
Did you install the latest Intel microcode update?

Thanks,

-- 
Shawn Webb
Cofounder and Security Engineer
HardenedBSD

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On 18.02.2018 17:50, Shawn Webb wrote:
>>
>> Strange thing is that tweaking `hw.ibrs_disable` has no effect on
>> `hw.ibrs_active` on my side.
> 
> Did you install the latest Intel microcode update?
> 
Hum, I thought I did, but I don't know actually if the following is the 
latest revision of the microcode:

#cpucontrol -u -v /dev/cpuctl0
cpucontrol: skipping /usr/local/share/cpucontrol/m32306c3_00000022.fw of 
rev 0x22: up to date




-- 
David Marec
https://lapinbilly.eu/