KVM: arm64: Move __smccc_workaround_1_smc to .rodata

This snippet of assembly is used by cpu_errata.c to overwrite parts of KVM hyp
vector. Move it to its own source file and change its ELF section to .rodata.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-3-dbrazdil@google.com

diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile
index 8c988078383907cd99d42b2a9b0813123964827e..5d8357ddc2344594c152c1d5bfcbee527d9cbab4 100644 (file)
--- a/arch/arm64/kvm/hyp/Makefile
+++ b/arch/arm64/kvm/hyp/Makefile
@@ -7,6 +7,7 @@ ccflags-y += -fno-stack-protector -DDISABLE_BRANCH_PROFILING \
                $(DISABLE_STACKLEAK_PLUGIN)
 
 obj-$(CONFIG_KVM) += hyp.o
+obj-$(CONFIG_KVM_INDIRECT_VECTORS) += smccc_wa.o
 
 hyp-y := vgic-v3-sr.o timer-sr.o aarch32.o vgic-v2-cpuif-proxy.o sysreg-sr.o \
         debug-sr.o entry.o switch.o fpsimd.o tlb.o hyp-entry.o

diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index 9c5cfb04170ee531c2f3e3fd80a8ab77f6fe4174..d362fad97cc83e35299c5601c188075ffb9906fa 100644 (file)
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -318,20 +318,4 @@ SYM_CODE_START(__bp_harden_hyp_vecs)
 1:     .org __bp_harden_hyp_vecs + __BP_HARDEN_HYP_VECS_SZ
        .org 1b
 SYM_CODE_END(__bp_harden_hyp_vecs)
-
-       .popsection
-
-SYM_CODE_START(__smccc_workaround_1_smc)
-       esb
-       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)
-1:     .org __smccc_workaround_1_smc + __SMCCC_WORKAROUND_1_SMC_SZ
-       .org 1b
-SYM_CODE_END(__smccc_workaround_1_smc)
 #endif

diff --git a/arch/arm64/kvm/hyp/smccc_wa.S b/arch/arm64/kvm/hyp/smccc_wa.S
new file mode 100644 (file)
index 0000000..b0441db
--- /dev/null
+++ b/arch/arm64/kvm/hyp/smccc_wa.S
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2015-2018 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/linkage.h>
+
+#include <asm/kvm_asm.h>
+#include <asm/kvm_mmu.h>
+
+       /*
+        * This is not executed directly and is instead copied into the vectors
+        * by install_bp_hardening_cb().
+        */
+       .data
+       .pushsection    .rodata
+       .global         __smccc_workaround_1_smc
+SYM_DATA_START(__smccc_workaround_1_smc)
+       esb
+       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)
+1:     .org __smccc_workaround_1_smc + __SMCCC_WORKAROUND_1_SMC_SZ
+       .org 1b
+SYM_DATA_END(__smccc_workaround_1_smc)