diff options
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 811773d1c1d0..ffb3e14dda60 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -726,6 +726,19 @@ static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused return is_kernel_in_hyp_mode(); } +static bool hyp_offset_low(const struct arm64_cpu_capabilities *entry, + int __unused) +{ + phys_addr_t idmap_addr = virt_to_phys(__hyp_idmap_text_start); + + /* + * Activate the lower HYP offset only if: + * - the idmap doesn't clash with it, + * - the kernel is not running at EL2. + */ + return idmap_addr > GENMASK(VA_BITS - 2, 0) && !is_kernel_in_hyp_mode(); +} + static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface", @@ -803,6 +816,12 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .field_pos = ID_AA64PFR0_EL0_SHIFT, .min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT, }, + { + .desc = "Reduced HYP mapping offset", + .capability = ARM64_HYP_OFFSET_LOW, + .def_scope = SCOPE_SYSTEM, + .matches = hyp_offset_low, + }, {}, }; |