diff options
author | Andrew Scull <ascull@google.com> | 2020-09-15 13:46:36 +0300 |
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committer | Marc Zyngier <maz@kernel.org> | 2020-09-15 20:39:03 +0300 |
commit | 4e3393a969a0bdaae83263918b6824b2d08c3996 (patch) | |
tree | 327744162b7e9be685044a5ca25fb24914380c0c /arch/arm64/kvm/hyp/nvhe/hyp-main.c | |
parent | 603d2bdaa57e48a33d57eeb88971b88fbe5875d6 (diff) | |
download | linux-4e3393a969a0bdaae83263918b6824b2d08c3996.tar.xz |
KVM: arm64: nVHE: Switch to hyp context for EL2
Save and restore the host context when switching to and from hyp. This
gives hyp its own context that the host will not see as a step towards a
full trust boundary between the two.
SP_EL0 and pointer authentication keys are currently shared between the
host and hyp so don't need to be switched yet.
Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-13-ascull@google.com
Diffstat (limited to 'arch/arm64/kvm/hyp/nvhe/hyp-main.c')
-rw-r--r-- | arch/arm64/kvm/hyp/nvhe/hyp-main.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c new file mode 100644 index 000000000000..570c3896f42e --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 - Google Inc + * Author: Andrew Scull <ascull@google.com> + */ + +#include <hyp/switch.h> + +#include <asm/kvm_asm.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_host.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> + +typedef unsigned long (*hypcall_fn_t) + (unsigned long, unsigned long, unsigned long); + +void handle_trap(struct kvm_cpu_context *host_ctxt) +{ + u64 esr = read_sysreg_el2(SYS_ESR); + hypcall_fn_t func; + unsigned long ret; + + if (ESR_ELx_EC(esr) != ESR_ELx_EC_HVC64) + hyp_panic(); + + /* + * __kvm_call_hyp takes a pointer in the host address space and + * up to three arguments. + */ + func = (hypcall_fn_t)kern_hyp_va(host_ctxt->regs.regs[0]); + ret = func(host_ctxt->regs.regs[1], + host_ctxt->regs.regs[2], + host_ctxt->regs.regs[3]); + host_ctxt->regs.regs[0] = ret; +} |