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| author | Marc Zyngier <maz@kernel.org> | 2020-06-15 23:03:30 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2020-06-22 13:42:50 +0300 |
| commit | 11ac16a4290b72efa8328cb144b727f3cbbdfa6a (patch) | |
| tree | f62037ce0c8d03ca86024806ad751c0d5c0314dd /arch/arm64/include/asm/kvm_ptrauth.h | |
| parent | 655169cec7bbf84f59faa9f824edb581eaecf78d (diff) | |
| download | linux-11ac16a4290b72efa8328cb144b727f3cbbdfa6a.tar.xz | |
KVM: arm64: Simplify PtrAuth alternative patching
We currently decide to execute the PtrAuth save/restore code based
on a set of branches that evaluate as (ARM64_HAS_ADDRESS_AUTH_ARCH ||
ARM64_HAS_ADDRESS_AUTH_IMP_DEF). This can be easily replaced by
a much simpler test as the ARM64_HAS_ADDRESS_AUTH capability is
exactly this expression.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/kvm_ptrauth.h')
| -rw-r--r-- | arch/arm64/include/asm/kvm_ptrauth.h | 30 |
1 files changed, 11 insertions, 19 deletions
diff --git a/arch/arm64/include/asm/kvm_ptrauth.h b/arch/arm64/include/asm/kvm_ptrauth.h index f1830173fa9e..0ddf98c3ba9f 100644 --- a/arch/arm64/include/asm/kvm_ptrauth.h +++ b/arch/arm64/include/asm/kvm_ptrauth.h @@ -61,44 +61,36 @@ /* * Both ptrauth_switch_to_guest and ptrauth_switch_to_host macros will - * check for the presence of one of the cpufeature flag - * ARM64_HAS_ADDRESS_AUTH_ARCH or ARM64_HAS_ADDRESS_AUTH_IMP_DEF and + * check for the presence ARM64_HAS_ADDRESS_AUTH, which is defined as + * (ARM64_HAS_ADDRESS_AUTH_ARCH || ARM64_HAS_ADDRESS_AUTH_IMP_DEF) and * then proceed ahead with the save/restore of Pointer Authentication - * key registers. + * key registers if enabled for the guest. */ .macro ptrauth_switch_to_guest g_ctxt, reg1, reg2, reg3 -alternative_if ARM64_HAS_ADDRESS_AUTH_ARCH - b 1000f +alternative_if_not ARM64_HAS_ADDRESS_AUTH + b .L__skip_switch\@ alternative_else_nop_endif -alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF - b 1001f -alternative_else_nop_endif -1000: mrs \reg1, hcr_el2 and \reg1, \reg1, #(HCR_API | HCR_APK) - cbz \reg1, 1001f + cbz \reg1, .L__skip_switch\@ add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 ptrauth_restore_state \reg1, \reg2, \reg3 -1001: +.L__skip_switch\@: .endm .macro ptrauth_switch_to_host g_ctxt, h_ctxt, reg1, reg2, reg3 -alternative_if ARM64_HAS_ADDRESS_AUTH_ARCH - b 2000f -alternative_else_nop_endif -alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF - b 2001f +alternative_if_not ARM64_HAS_ADDRESS_AUTH + b .L__skip_switch\@ alternative_else_nop_endif -2000: mrs \reg1, hcr_el2 and \reg1, \reg1, #(HCR_API | HCR_APK) - cbz \reg1, 2001f + cbz \reg1, .L__skip_switch\@ add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 ptrauth_save_state \reg1, \reg2, \reg3 add \reg1, \h_ctxt, #CPU_APIAKEYLO_EL1 ptrauth_restore_state \reg1, \reg2, \reg3 isb -2001: +.L__skip_switch\@: .endm #else /* !CONFIG_ARM64_PTR_AUTH */ |