On Wed, 8 Sep 2021 20:17:17 +1000, Nicholas Piggin wrote:
> The rfscv instruction does not work correctly with the fake-suspend mode
> in POWER9, which can end up with the hypervisor restoring an incorrect
> checkpoint.
>
> Work around this by setting the _TIF_RESTOREALL flag if a system call
> returns to a transaction active state, causing rfid to be used instead
> of rfscv to return, which will do the right thing. The contents of the
> registers are irrelevant because they will be overwritten in this case
> anyway.
>
> [...]
Applied to powerpc/fixes.
[1/2] powerpc/64s: system call rfscv workaround for TM bugs
https://git.kernel.org/powerpc/c/ae7aaecc3f2f78b76ab3a8d6178610f55aadfa56
[2/2] KVM: PPC: Book3S HV: Tolerate treclaim. in fake-suspend mode changing registers
https://git.kernel.org/powerpc/c/267cdfa21385d78c794768233678756e32b39ead
cheers
