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arm64: cpufeatures: Drop the ARM64_HYP_OFFSET_LOW feature flag

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Now that we can dynamically compute the kernek/hyp VA mask, there
is no need for a feature flag to trigger the alternative patching.
Let's drop the flag and everything that depends on it.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
This commit is contained in:
Marc Zyngier 2017-12-03 17:42:37 +00:00
parent 2b4d1606aa
commit a1efdff442
2 changed files with 1 additions and 20 deletions
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2
arch/arm64/include/asm/cpucaps.h
View File

@ -32,7 +32,7 @@
#define ARM64_HAS_VIRT_HOST_EXTN 11
#define ARM64_WORKAROUND_CAVIUM_27456 12
#define ARM64_HAS_32BIT_EL0 13
#define ARM64_HYP_OFFSET_LOW 14
/* #define ARM64_UNALLOCATED_ENTRY 14 */
#define ARM64_MISMATCHED_CACHE_LINE_SIZE 15
#define ARM64_HAS_NO_FPSIMD 16
#define ARM64_WORKAROUND_REPEAT_TLBI 17

19
arch/arm64/kernel/cpufeature.c
View File

@ -831,19 +831,6 @@ 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 = __pa_symbol(__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 bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unused)
{
u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
@ -1029,12 +1016,6 @@ 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,
},
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
{
.desc = "Kernel page table isolation (KPTI)",