Re: [PATCH AUTOSEL 4.19 022/146] cpupower: Fix coredump on VMWare

[Sasha Levin]

On Thu, Nov 01, 2018 at 07:43:35AM -0400, Prarit Bhargava wrote:
> On 10/31/2018 07:03 PM, Sasha Levin wrote:
> > From: Prarit Bhargava <prarit@xxxxxxxxxx>
> >
> > [ Upstream commit f69ffc5d3db8f1f03fd6d1df5930f9a1fbd787b6 ]
> >
> > cpupower crashes on VMWare guests.  The guests have the AMD PStateDef MSR
> > (0xC0010064 + state number) set to zero.  As a result fid and did are zero
> > and the crash occurs because of a divide by zero (cof = fid/did).  This
> > can be prevented by checking the enable bit in the PStateDef MSR before
> > calculating cof.  By doing this the value of pstate[i] remains zero and
> > the value can be tested before displaying the active Pstates.
> >
> > Check the enable bit in the PstateDef register for all supported families
> > and only print out enabled Pstates.
>
> Hi Sasha,
>
> This patch, f69ffc5d3db8, depends on 8c22e2f69592 ("cpupower: Fix AMD Family
> 0x17 msr_pstate size").  Without 8c22e2f69592 the patch below will always read a
> value of "0" and not output the correct data.
>
> 8c22e2f69592 must be applied to any stable branch that f69ffc5d3db8 is applied to.

I'll grab it too, thank you.

--
Thanks,
Sasha