[RESEND][SRU][Xenial][PATCH 0/1] KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread

[Joseph Salisbury]

If possible, can this SRU request be reviewed?

Thanks,

Joe


On 11/03/2017 01:05 PM, Joseph Salisbury wrote:
> BugLink: http://bugs.launchpad.net/bugs/1727331
>
> == SRU Justification ==
> Xenial does not include the patch: 
> "KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread", 
> which is commit 88b02cf97bb7 in the upstream Linux kernel repository. The 
> symptom of not having this patch is that guests running with threads > 1 
> (that is, in SMT2, SMT4 or SMT8 mode) can give spurious soft-lockup messages 
> when they are not in fact locked up, if the guest kernel uses the VTB 
> (virtual timebase) register in its softlockup detector code.
>
> IBM provided this backport of commit 88b02cf97bb7.
>     
> == Fix ==
> commit 88b02cf97bb7e742db3e31671d54177e3e19fd89
> Author: Paul Mackerras <paulus at ozlabs.org>
> Date:   Thu Sep 15 13:42:52 2016 +1000
>
>     KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
>
> == Regression Potential ==
> This patch is specific to powerpc.  It was provided by and tested by IBM.
>
> == Test Case ==
> A test kernel was built with this patch and tested by the original bug reporter.
> The bug reporter states the test kernel resolved the bug.
>
> Paul Mackerras (1):
>   KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
>
>  arch/powerpc/include/asm/kvm_book3s.h   |  1 +
>  arch/powerpc/include/asm/kvm_host.h     |  2 +-
>  arch/powerpc/kernel/asm-offsets.c       |  2 +-
>  arch/powerpc/kvm/book3s.c               |  6 ------
>  arch/powerpc/kvm/book3s_emulate.c       |  2 +-
>  arch/powerpc/kvm/book3s_hv.c            | 14 +++++++++++---
>  arch/powerpc/kvm/book3s_hv_rmhandlers.S | 14 +++++++-------
>  arch/powerpc/kvm/book3s_pr.c            |  8 +++++++-
>  8 files changed, 29 insertions(+), 20 deletions(-)
>