APPLIED: [LP 1851709] Cannot launch KVM guests if EPT is disabled

[Thomas Lamprecht]

On 11/12/19 11:32 AM, Stefan Bader wrote:
> On 12.11.19 10:16, Thadeu Lima de Souza Cascardo wrote:
>> It has been reported as failure to launch 64-bit linux VMs when kvm-intel
>> ept module parameter is off. It is off by default on old Intel CPUs.
>>
>> The bionic revert has been tested as works fine. kvm-unit-tests has been
>> run there as well and no regressions found.
>>
>>
>>
> Applied to disco+bionic/master-next. Thanks.
> 

Why did you go the revert route and not the "backport the missing
pieces"[0] one? For Disco cherry-picking upstream commit
bf03d4f9334728bf7c8ffc7de787df48abd6340e is enough (tested here).  For
disco the backport for 4.14[0] should be a working (did not tested yet).
The patch which made problem show up was not a issue itself, and a valid
fix, older kernel just missed some supporting fix, i.e., [0]. So, FWIWW,
IMO it would be better to backport that instead of reverting.

cheers,
Thomas

[0]: https://lore.kernel.org/stable/20191111233718.28438-1-sean.j.christopherson@intel.com/T/