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

Sasha Levin
2018-11-01T15:47:21Z

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@redhat.com>
>>
>> [ 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