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arm64: Move the content of bpi.S to hyp-entry.S 

bpi.S was introduced as we were starting to build the Spectre v2
mitigation framework, and it was rather unclear that it would
become strictly KVM specific.

Now that the picture is a lot clearer, let's move the content
of that file to hyp-entry.S, where it actually belong.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
hifive-unleashed-5.1
Marc Zyngier 2018-04-10 11:36:45 +01:00 committed by Will Deacon
parent 22765f30db
commit e8b22d0f45
4 changed files with 65 additions and 91 deletions
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2
arch/arm64/kernel/Makefile
View File

@ -55,8 +55,6 @@ arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o
arm64-obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
arm64-obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o
arm64-obj-$(CONFIG_KVM_INDIRECT_VECTORS)+= bpi.o
obj-y += $(arm64-obj-y) vdso/ probes/
obj-m += $(arm64-obj-m)
head-y := head.o

86
arch/arm64/kernel/bpi.S
View File

@ -1,86 +0,0 @@
/*
* Contains CPU specific branch predictor invalidation sequences
*
* Copyright (C) 2018 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/linkage.h>
#include <linux/arm-smccc.h>
#include <asm/alternative.h>
#include <asm/mmu.h>
.macro hyp_ventry
.align 7
1: .rept 27
nop
.endr
/*
* The default sequence is to directly branch to the KVM vectors,
* using the computed offset. This applies for VHE as well as
* !ARM64_HARDEN_EL2_VECTORS.
*
* For ARM64_HARDEN_EL2_VECTORS configurations, this gets replaced
* with:
*
* stp x0, x1, [sp, #-16]!
* movz x0, #(addr & 0xffff)
* movk x0, #((addr >> 16) & 0xffff), lsl #16
* movk x0, #((addr >> 32) & 0xffff), lsl #32
* br x0
*
* Where addr = kern_hyp_va(__kvm_hyp_vector) + vector-offset + 4.
* See kvm_patch_vector_branch for details.
*/
alternative_cb kvm_patch_vector_branch
b __kvm_hyp_vector + (1b - 0b)
nop
nop
nop
nop
alternative_cb_end
.endm
.macro generate_vectors
0:
.rept 16
hyp_ventry
.endr
.org 0b + SZ_2K // Safety measure
.endm
.text
.pushsection .hyp.text, "ax"
.align 11
ENTRY(__bp_harden_hyp_vecs_start)
.rept BP_HARDEN_EL2_SLOTS
generate_vectors
.endr
ENTRY(__bp_harden_hyp_vecs_end)
.popsection
ENTRY(__smccc_workaround_1_smc_start)
sub sp, sp, #(8 * 4)
stp x2, x3, [sp, #(8 * 0)]
stp x0, x1, [sp, #(8 * 2)]
mov w0, #ARM_SMCCC_ARCH_WORKAROUND_1
smc #0
ldp x2, x3, [sp, #(8 * 0)]
ldp x0, x1, [sp, #(8 * 2)]
add sp, sp, #(8 * 4)
ENTRY(__smccc_workaround_1_smc_end)

4
arch/arm64/kernel/cpu_errata.c
View File

@ -86,7 +86,7 @@ atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1);
DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
#ifdef CONFIG_KVM
#ifdef CONFIG_KVM_INDIRECT_VECTORS
extern char __smccc_workaround_1_smc_start[];
extern char __smccc_workaround_1_smc_end[];
@ -137,7 +137,7 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
{
__this_cpu_write(bp_hardening_data.fn, fn);
}
#endif /* CONFIG_KVM */
#endif /* CONFIG_KVM_INDIRECT_VECTORS */
static void install_bp_hardening_cb(const struct arm64_cpu_capabilities *entry,
bp_hardening_cb_t fn,

64
arch/arm64/kvm/hyp/hyp-entry.S
View File

@ -1,5 +1,5 @@
/*
* Copyright (C) 2015 - ARM Ltd
* Copyright (C) 2015-2018 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
@ -24,6 +24,7 @@
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>
#include <asm/mmu.h>
.text
.pushsection .hyp.text, "ax"
@ -237,3 +238,64 @@ ENTRY(__kvm_hyp_vector)
invalid_vect el1_fiq_invalid // FIQ 32-bit EL1
valid_vect el1_error // Error 32-bit EL1
ENDPROC(__kvm_hyp_vector)
#ifdef CONFIG_KVM_INDIRECT_VECTORS
.macro hyp_ventry
.align 7
1: .rept 27
nop
.endr
/*
* The default sequence is to directly branch to the KVM vectors,
* using the computed offset. This applies for VHE as well as
* !ARM64_HARDEN_EL2_VECTORS.
*
* For ARM64_HARDEN_EL2_VECTORS configurations, this gets replaced
* with:
*
* stp x0, x1, [sp, #-16]!
* movz x0, #(addr & 0xffff)
* movk x0, #((addr >> 16) & 0xffff), lsl #16
* movk x0, #((addr >> 32) & 0xffff), lsl #32
* br x0
*
* Where addr = kern_hyp_va(__kvm_hyp_vector) + vector-offset + 4.
* See kvm_patch_vector_branch for details.
*/
alternative_cb kvm_patch_vector_branch
b __kvm_hyp_vector + (1b - 0b)
nop
nop
nop
nop
alternative_cb_end
.endm
.macro generate_vectors
0:
.rept 16
hyp_ventry
.endr
.org 0b + SZ_2K // Safety measure
.endm
.align 11
ENTRY(__bp_harden_hyp_vecs_start)
.rept BP_HARDEN_EL2_SLOTS
generate_vectors
.endr
ENTRY(__bp_harden_hyp_vecs_end)
.popsection
ENTRY(__smccc_workaround_1_smc_start)
sub sp, sp, #(8 * 4)
stp x2, x3, [sp, #(8 * 0)]
stp x0, x1, [sp, #(8 * 2)]
mov w0, #ARM_SMCCC_ARCH_WORKAROUND_1
smc #0
ldp x2, x3, [sp, #(8 * 0)]
ldp x0, x1, [sp, #(8 * 2)]
add sp, sp, #(8 * 4)
ENTRY(__smccc_workaround_1_smc_end)
#endif