Admitedly, passing id_aa64mmfr1.vh=0 on the command-line isn't that easy to understand, and it is likely that users would much prefer write "kvm-arm.mode=nvhe", or "...=protected".
So here you go. This has the added advantage that we can now always honor the "kvm-arm.mode=protected" option, even when booting on a VHE system. Signed-off-by: Marc Zyngier <m...@kernel.org> Acked-by: Catalin Marinas <catalin.mari...@arm.com> Acked-by: David Brazdil <dbraz...@google.com> --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ arch/arm64/kernel/idreg-override.c | 2 ++ arch/arm64/kvm/arm.c | 3 +++ 3 files changed, 8 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9e3cdb271d06..2786fd39a047 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2257,6 +2257,9 @@ kvm-arm.mode= [KVM,ARM] Select one of KVM/arm64's modes of operation. + nvhe: Standard nVHE-based mode, without support for + protected guests. + protected: nVHE-based mode with support for guests whose state is kept private from the host. Not valid if the kernel is running in EL2. diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index 4fad3fc4d104..cbb8eaa48742 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -39,6 +39,8 @@ static const struct { const char *alias; const char *feature; } aliases[] __initdata = { + { "kvm-arm.mode=nvhe", "id_aa64mmfr1.vh=0" }, + { "kvm-arm.mode=protected", "id_aa64mmfr1.vh=0" }, }; static char *cmdline_contains_option(const char *cmdline, const char *option) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 04c44853b103..597565a65ca2 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1966,6 +1966,9 @@ static int __init early_kvm_mode_cfg(char *arg) return 0; } + if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) + return 0; + return -EINVAL; } early_param("kvm-arm.mode", early_kvm_mode_cfg); -- 2.29.2 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm