On 20/12/18 21:25, Sean Christopherson wrote:
> Despite all but one patch being KVM cleanup, that one outlier is the
> true catalyst for this series. The outlier, patch 3/11, removes an
> optimization tweak from the __noclone macro that was added by commit
> 95272c29378e ("compiler-gcc: disable -ftracer for __noclone functions")
> to workaround a compiler error in KVM's esoteric VMX assembly code.
>
> Unbeknownst at the time, using the __optimize__ attribute causes GCC
> to reset to -O2 optimization defaults, which has several unintended
> side effects including dropping -fno-omit-frame-pointer and preventing
> GCC from properly inlining function calls due to the functions having
> incompatible optimization attributes.
>
> Patches 1/11 and 2/11 fix the offending KVM code and eliminate its
> usage of __noclone, allowing patch 3/11 to remove "no-tracer" from the
> __noclone macro.
Very nice! I'm applying 1-3 right away, while the rest should wait for
4.22.
Paolo
