Folks, this series is the KVM side of the ongoing quest to confine instrumentation to safe places and ensure that RCU and context tracking state is correct. The async #PF changes are in the tip tree already as they conflict with the entry code rework. The minimal set of commits to carry these have been isolated and tagged: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git noinstr-x86-kvm-2020-05-16 Paolo, please pull this into your next branch to avoid conflicts in next. The prerequisites for the following KVM specific changes come with that tag so that you have no merge dependencies. The tag has also been merged into git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/entry where the x86 core #PF entry code changes will be queued soon as well. The KVM specific patches which deal with the RCU and context tracking state and the protection against instrumentation in sensitive places have been split out from the larger entry/noinstr series: https://lore.kernel.org/r/20200505134112.272268764@xxxxxxxxxxxxx The patches deal with: - Placing the guest_enter/exit() calls at the correct place - Moving the sensitive VMENTER/EXIT code into the non-instrumentable code section. - Fixup the tracing code to comply with the non-instrumentation rules - Use native functions to access CR2 and the GS base MSR in the critical code pathes to prevent them from being instrumented. The patches apply on top of git://git.kernel.org/pub/scm/linux/kernel/git/kvm/kvm.git next with the noinstr-x86-kvm-2020-05-16 tag from the tip tree merged in. For reference the whole lot is available from: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git kvm/noinstr Thanks, tglx --- include/asm/hardirq.h | 4 +- include/asm/kvm_host.h | 8 +++++ kvm/svm/svm.c | 65 ++++++++++++++++++++++++++++++++++------ kvm/svm/vmenter.S | 2 - kvm/vmx/ops.h | 4 ++ kvm/vmx/vmenter.S | 5 ++- kvm/vmx/vmx.c | 78 ++++++++++++++++++++++++++++++++++++++----------- kvm/x86.c | 4 -- 8 files changed, 137 insertions(+), 33 deletions(-)
