releases/4.20.4/arm64-kvm-consistently-handle-host-hcr_el2-flags.patch

   1 From cfc22a22ef038242b76b463a279801a96b544244 Mon Sep 17 00:00:00 2001
   2 From: Mark Rutland <mark.rutland@arm.com>
   3 Date: Fri, 7 Dec 2018 18:39:21 +0000
   4 Subject: arm64/kvm: consistently handle host HCR_EL2 flags
   5
   6 [ Upstream commit 4eaed6aa2c628101246bcabc91b203bfac1193f8 ]
   7
   8 In KVM we define the configuration of HCR_EL2 for a VHE HOST in
   9 HCR_HOST_VHE_FLAGS, but we don't have a similar definition for the
  10 non-VHE host flags, and open-code HCR_RW. Further, in head.S we
  11 open-code the flags for VHE and non-VHE configurations.
  12
  13 In future, we're going to want to configure more flags for the host, so
  14 lets add a HCR_HOST_NVHE_FLAGS defintion, and consistently use both
  15 HCR_HOST_VHE_FLAGS and HCR_HOST_NVHE_FLAGS in the kvm code and head.S.
  16
  17 We now use mov_q to generate the HCR_EL2 value, as we use when
  18 configuring other registers in head.S.
  19
  20 Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
  21 Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
  22 Signed-off-by: Mark Rutland <mark.rutland@arm.com>
  23 Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
  24 Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
  25 Cc: Catalin Marinas <catalin.marinas@arm.com>
  26 Cc: Marc Zyngier <marc.zyngier@arm.com>
  27 Cc: Will Deacon <will.deacon@arm.com>
  28 Cc: kvmarm@lists.cs.columbia.edu
  29 Signed-off-by: Will Deacon <will.deacon@arm.com>
  30 Signed-off-by: Sasha Levin <sashal@kernel.org>
  31 ---
  32  arch/arm64/include/asm/kvm_arm.h | 1 +
  33  arch/arm64/kernel/head.S         | 5 ++---
  34  arch/arm64/kvm/hyp/switch.c      | 2 +-
  35  3 files changed, 4 insertions(+), 4 deletions(-)
  36
  37 diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
  38 index 2dafd936d84d..7b914c6fb855 100644
  39 --- a/arch/arm64/include/asm/kvm_arm.h
  40 +++ b/arch/arm64/include/asm/kvm_arm.h
  41 @@ -87,6 +87,7 @@
  42                          HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW | HCR_TLOR | \
  43                          HCR_FMO | HCR_IMO)
  44  #define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF)
  45 +#define HCR_HOST_NVHE_FLAGS (HCR_RW)
  46  #define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H)
  47
  48  /* TCR_EL2 Registers bits */
  49 diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
  50 index 4471f570a295..b207a2ce4bc6 100644
  51 --- a/arch/arm64/kernel/head.S
  52 +++ b/arch/arm64/kernel/head.S
  53 @@ -496,10 +496,9 @@ ENTRY(el2_setup)
  54  #endif
  55
  56         /* Hyp configuration. */
  57 -       mov     x0, #HCR_RW                     // 64-bit EL1
  58 +       mov_q   x0, HCR_HOST_NVHE_FLAGS
  59         cbz     x2, set_hcr
  60 -       orr     x0, x0, #HCR_TGE                // Enable Host Extensions
  61 -       orr     x0, x0, #HCR_E2H
  62 +       mov_q   x0, HCR_HOST_VHE_FLAGS
  63  set_hcr:
  64         msr     hcr_el2, x0
  65         isb
  66 diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
  67 index 7cc175c88a37..f6e02cc4d856 100644
  68 --- a/arch/arm64/kvm/hyp/switch.c
  69 +++ b/arch/arm64/kvm/hyp/switch.c
  70 @@ -157,7 +157,7 @@ static void __hyp_text __deactivate_traps_nvhe(void)
  71         mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
  72
  73         write_sysreg(mdcr_el2, mdcr_el2);
  74 -       write_sysreg(HCR_RW, hcr_el2);
  75 +       write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2);
  76         write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
  77  }
  78
  79 --
  80 2.19.1
  81