From: Marc Zyngier <marc.zyngier@arm.com>
Date: Tue, 10 Apr 2018 11:36:44 +0100
Subject: arm64: Get rid of __smccc_workaround_1_hvc_*
Git-commit: 22765f30dbaf1118c6ff0fcb8b99c9f2b4d396d5
Patch-mainline: v4.17-rc1
References: bsc#1174547
The very existence of __smccc_workaround_1_hvc_* is a thinko, as
KVM will never use a HVC call to perform the branch prediction
invalidation. Even as a nested hypervisor, it would use an SMC
instruction.
Let's get rid of it.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
arch/arm64/kernel/bpi.S | 12 ++----------
arch/arm64/kernel/cpu_errata.c | 9 +++------
2 files changed, 5 insertions(+), 16 deletions(-)
--- a/arch/arm64/kernel/bpi.S
+++ b/arch/arm64/kernel/bpi.S
@@ -55,21 +55,13 @@ ENTRY(__bp_harden_hyp_vecs_start)
.endr
ENTRY(__bp_harden_hyp_vecs_end)
-.macro smccc_workaround_1 inst
+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
- \inst #0
+ smc #0
ldp x2, x3, [sp, #(8 * 0)]
ldp x0, x1, [sp, #(8 * 2)]
add sp, sp, #(8 * 4)
-.endm
-
-ENTRY(__smccc_workaround_1_smc_start)
- smccc_workaround_1 smc
ENTRY(__smccc_workaround_1_smc_end)
-
-ENTRY(__smccc_workaround_1_hvc_start)
- smccc_workaround_1 hvc
-ENTRY(__smccc_workaround_1_hvc_end)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -73,8 +73,6 @@ DEFINE_PER_CPU_READ_MOSTLY(struct bp_har
#ifdef CONFIG_KVM
extern char __smccc_workaround_1_smc_start[];
extern char __smccc_workaround_1_smc_end[];
-extern char __smccc_workaround_1_hvc_start[];
-extern char __smccc_workaround_1_hvc_end[];
static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
const char *hyp_vecs_end)
@@ -119,8 +117,6 @@ static void __install_bp_hardening_cb(bp
#else
#define __smccc_workaround_1_smc_start NULL
#define __smccc_workaround_1_smc_end NULL
-#define __smccc_workaround_1_hvc_start NULL
-#define __smccc_workaround_1_hvc_end NULL
static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
const char *hyp_vecs_start,
@@ -194,8 +190,9 @@ enable_smccc_arch_workaround_1(const str
if ((int)res.a0 < 0)
return;
cb = call_hvc_arch_workaround_1;
- smccc_start = __smccc_workaround_1_hvc_start;
- smccc_end = __smccc_workaround_1_hvc_end;
+ /* This is a guest, no need to patch KVM vectors */
+ smccc_start = NULL;
+ smccc_end = NULL;
break;
case PSCI_CONDUIT_SMC: