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From: Marc Zyngier <marc.zyngier@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	Christoffer Dall <christoffer.dall@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	kvmarm@lists.cs.columbia.edu
Subject: [PATCH v3 00/23] arm64: Virtualization Host Extension support
Date: Wed,  3 Feb 2016 17:59:53 +0000	[thread overview]
Message-ID: <1454522416-6874-1-git-send-email-marc.zyngier@arm.com> (raw)

ARMv8.1 comes with the "Virtualization Host Extension" (VHE for
short), which enables simpler support of Type-2 hypervisors.

This extension allows the kernel to directly run at EL2, and
significantly reduces the number of system registers shared between
host and guest, reducing the overhead of virtualization.

In order to have the same kernel binary running on all versions of the
architecture, this series makes heavy use of runtime code patching.

The first 22 patches massage the KVM code to deal with VHE and enable
Linux to run at EL2. The last patch catches an ugly case when VHE
capable CPUs are paired with some of their less capable siblings. This
should never happen, but hey...

I have deliberately left out some of the more "advanced"
optimizations, as they are likely to distract the reviewer from the
core infrastructure, which is what I care about at the moment.

Note: GDB is currently busted on VHE systems, as it checks for version
      6 on the debug architecture, while VHE is version 7. The
      binutils people are on the case.

This has been tested on the FVP_Base_SLV-V8-A model, and based on
v4.5-rc2. I've put a branch out on:

git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git kvm-arm64/vhe

* From v2:
  - Added support for perf to count kernel events in EL2
  - Added support for EL2 breakpoints
  - Moved the VTCR_EL2 setup from assembly to C
  - Made the fault handling easier to understand (hopefuly)
  - Plenty of smaller fixups

* From v1:
  - Full rewrite now that the World Switch is written in C code.
  - Dropped the "early IRQ handling" for the moment.

Marc Zyngier (23):
  arm/arm64: KVM: Add hook for C-based stage2 init
  arm64: KVM: Switch to C-based stage2 init
  arm/arm64: Add new is_kernel_in_hyp_mode predicate
  arm64: Allow the arch timer to use the HYP timer
  arm64: Add ARM64_HAS_VIRT_HOST_EXTN feature
  arm64: KVM: Skip HYP setup when already running in HYP
  arm64: KVM: VHE: Patch out use of HVC
  arm64: KVM: VHE: Patch out kern_hyp_va
  arm64: KVM: VHE: Introduce unified system register accessors
  arm64: KVM: VHE: Differenciate host/guest sysreg save/restore
  arm64: KVM: VHE: Split save/restore of registers shared between guest
    and host
  arm64: KVM: VHE: Use unified system register accessors
  arm64: KVM: VHE: Enable minimal sysreg save/restore
  arm64: KVM: VHE: Make __fpsimd_enabled VHE aware
  arm64: KVM: VHE: Implement VHE activate/deactivate_traps
  arm64: KVM: VHE: Use unified sysreg accessors for timer
  arm64: KVM: VHE: Add fpsimd enabling on guest access
  arm64: KVM: VHE: Add alternative panic handling
  arm64: KVM: Move most of the fault decoding to C
  arm64: perf: Count EL2 events if the kernel is running in HYP
  arm64: hw_breakpoint: Allow EL2 breakpoints if running in HYP
  arm64: VHE: Add support for running Linux in EL2 mode
  arm64: Panic when VHE and non VHE CPUs coexist

 arch/arm/include/asm/kvm_host.h        |   4 +
 arch/arm/include/asm/virt.h            |   5 +
 arch/arm/kvm/arm.c                     | 174 +++++++++++++++++++----------
 arch/arm/kvm/mmu.c                     |   7 ++
 arch/arm64/Kconfig                     |  13 +++
 arch/arm64/include/asm/cpufeature.h    |   3 +-
 arch/arm64/include/asm/hw_breakpoint.h |  49 ++++++---
 arch/arm64/include/asm/kvm_arm.h       |   6 +-
 arch/arm64/include/asm/kvm_asm.h       |   2 +
 arch/arm64/include/asm/kvm_emulate.h   |   3 +
 arch/arm64/include/asm/kvm_host.h      |   6 +
 arch/arm64/include/asm/kvm_mmu.h       |  12 +-
 arch/arm64/include/asm/virt.h          |  27 +++++
 arch/arm64/kernel/asm-offsets.c        |   3 -
 arch/arm64/kernel/cpufeature.c         |  11 ++
 arch/arm64/kernel/head.S               |  48 +++++++-
 arch/arm64/kernel/perf_event.c         |  14 ++-
 arch/arm64/kernel/smp.c                |   3 +
 arch/arm64/kvm/hyp-init.S              |  18 ---
 arch/arm64/kvm/hyp.S                   |   7 ++
 arch/arm64/kvm/hyp/Makefile            |   1 +
 arch/arm64/kvm/hyp/entry.S             |   6 +
 arch/arm64/kvm/hyp/hyp-entry.S         | 109 ++++++------------
 arch/arm64/kvm/hyp/hyp.h               | 108 ++++++++++++++++--
 arch/arm64/kvm/hyp/s2-setup.c          |  44 ++++++++
 arch/arm64/kvm/hyp/switch.c            | 196 ++++++++++++++++++++++++++++++---
 arch/arm64/kvm/hyp/sysreg-sr.c         | 147 ++++++++++++++++---------
 arch/arm64/kvm/hyp/timer-sr.c          |  10 +-
 drivers/clocksource/arm_arch_timer.c   |  96 +++++++++-------
 29 files changed, 837 insertions(+), 295 deletions(-)
 create mode 100644 arch/arm64/kvm/hyp/s2-setup.c

-- 
2.1.4

             reply	other threads:[~2016-02-03 18:00 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-03 17:59 Marc Zyngier [this message]
2016-02-03 17:59 ` [PATCH v3 01/23] arm/arm64: KVM: Add hook for C-based stage2 init Marc Zyngier
2016-02-03 17:59 ` [PATCH v3 02/23] arm64: KVM: Switch to " Marc Zyngier
2016-02-03 17:59 ` [PATCH v3 03/23] arm/arm64: Add new is_kernel_in_hyp_mode predicate Marc Zyngier
2016-02-08 14:41   ` Catalin Marinas
2016-02-03 17:59 ` [PATCH v3 04/23] arm64: Allow the arch timer to use the HYP timer Marc Zyngier
2016-02-03 17:59 ` [PATCH v3 05/23] arm64: Add ARM64_HAS_VIRT_HOST_EXTN feature Marc Zyngier
2016-02-08 14:42   ` Catalin Marinas
2016-02-03 17:59 ` [PATCH v3 06/23] arm64: KVM: Skip HYP setup when already running in HYP Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 07/23] arm64: KVM: VHE: Patch out use of HVC Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 08/23] arm64: KVM: VHE: Patch out kern_hyp_va Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 09/23] arm64: KVM: VHE: Introduce unified system register accessors Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 10/23] arm64: KVM: VHE: Differenciate host/guest sysreg save/restore Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 11/23] arm64: KVM: VHE: Split save/restore of registers shared between guest and host Marc Zyngier
2016-02-04 19:15   ` Christoffer Dall
2016-02-03 18:00 ` [PATCH v3 12/23] arm64: KVM: VHE: Use unified system register accessors Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 13/23] arm64: KVM: VHE: Enable minimal sysreg save/restore Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 14/23] arm64: KVM: VHE: Make __fpsimd_enabled VHE aware Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 15/23] arm64: KVM: VHE: Implement VHE activate/deactivate_traps Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 16/23] arm64: KVM: VHE: Use unified sysreg accessors for timer Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 17/23] arm64: KVM: VHE: Add fpsimd enabling on guest access Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 18/23] arm64: KVM: VHE: Add alternative panic handling Marc Zyngier
2016-02-03 18:00 ` [PATCH v3 19/23] arm64: KVM: Move most of the fault decoding to C Marc Zyngier
2016-02-04 19:20   ` Christoffer Dall
2016-02-08 14:44   ` Catalin Marinas
2016-02-03 18:00 ` [PATCH v3 20/23] arm64: perf: Count EL2 events if the kernel is running in HYP Marc Zyngier
2016-02-04 19:23   ` Christoffer Dall
2016-02-05  9:02     ` Marc Zyngier
2016-02-08 14:48   ` Catalin Marinas
2016-02-03 18:00 ` [PATCH v3 21/23] arm64: hw_breakpoint: Allow EL2 breakpoints if " Marc Zyngier
2016-02-08 15:56   ` Catalin Marinas
2016-02-08 16:45     ` Marc Zyngier
2016-02-08 16:52       ` Catalin Marinas
2016-02-03 18:00 ` [PATCH v3 22/23] arm64: VHE: Add support for running Linux in EL2 mode Marc Zyngier
2016-02-04 19:25   ` Christoffer Dall
2016-02-08 15:58   ` Catalin Marinas
2016-02-03 18:00 ` [PATCH v3 23/23] arm64: Panic when VHE and non VHE CPUs coexist Marc Zyngier
2016-02-04 19:25   ` Christoffer Dall
2016-02-08 16:04   ` Catalin Marinas
2016-02-08 16:24     ` Mark Rutland
2016-02-09 12:02       ` Catalin Marinas
2016-02-04 19:26 ` [PATCH v3 00/23] arm64: Virtualization Host Extension support Christoffer Dall
2016-02-05  8:56   ` Marc Zyngier

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