In an effort to clarify and simplify the annotation of assembly functions
in the kernel new macros have been introduced. These replace ENTRY and
ENDPROC with separate annotations for standard C callable functions,
data and code with different calling conventions.
Using these for __smccc_workaround_1_smc is more involved than for most
symbols as this symbol is annotated quite unusually, rather than just have
the explicit symbol we define _start and _end symbols which we then use to
compute the length. This does not play at all nicely with the new style
macros. Instead define a constant for the size of the function and use that
in both the C code and for .org based size checks in the assembly code.
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_asm.h | 4 ++++
arch/arm64/kernel/cpu_errata.c | 14 ++++++--------
arch/arm64/kvm/hyp/hyp-entry.S | 6 ++++--
3 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 44a243754c1b..7c7eeeaab9fa 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -36,6 +36,8 @@
*/
#define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE)
+#define __SMCCC_WORKAROUND_1_SMC_SZ 36
+
#ifndef __ASSEMBLY__
#include <linux/mm.h>
@@ -75,6 +77,8 @@ extern void __vgic_v3_init_lrs(void);
extern u32 __kvm_get_mdcr_el2(void);
+extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
+
/* Home-grown __this_cpu_{ptr,read} variants that always work at HYP */
#define __hyp_this_cpu_ptr(sym) \
({ \
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 0af2201cefda..6a2ca339741c 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -11,6 +11,7 @@
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/cpufeature.h>
+#include <asm/kvm_asm.h>
#include <asm/smp_plat.h>
static bool __maybe_unused
@@ -113,9 +114,6 @@ 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_INDIRECT_VECTORS
-extern char __smccc_workaround_1_smc_start[];
-extern char __smccc_workaround_1_smc_end[];
-
static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
const char *hyp_vecs_end)
{
@@ -163,9 +161,6 @@ static void install_bp_hardening_cb(bp_hardening_cb_t fn,
raw_spin_unlock(&bp_lock);
}
#else
-#define __smccc_workaround_1_smc_start NULL
-#define __smccc_workaround_1_smc_end NULL
-
static void install_bp_hardening_cb(bp_hardening_cb_t fn,
const char *hyp_vecs_start,
const char *hyp_vecs_end)
@@ -239,11 +234,14 @@ static int detect_harden_bp_fw(void)
smccc_end = NULL;
break;
+#if IS_ENABLED(CONFIG_KVM_ARM_HOST)
case SMCCC_CONDUIT_SMC:
cb = call_smc_arch_workaround_1;
- smccc_start = __smccc_workaround_1_smc_start;
- smccc_end = __smccc_workaround_1_smc_end;
+ smccc_start = __smccc_workaround_1_smc;
+ smccc_end = __smccc_workaround_1_smc +
+ __SMCCC_WORKAROUND_1_SMC_SZ;
break;
+#endif
default:
return -1;
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index 1e2ab928a92f..c2a13ab3c471 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -322,7 +322,7 @@ SYM_CODE_END(__bp_harden_hyp_vecs)
.popsection
-ENTRY(__smccc_workaround_1_smc_start)
+SYM_CODE_START(__smccc_workaround_1_smc)
esb
sub sp, sp, #(8 * 4)
stp x2, x3, [sp, #(8 * 0)]
@@ -332,5 +332,7 @@ ENTRY(__smccc_workaround_1_smc_start)
ldp x2, x3, [sp, #(8 * 0)]
ldp x0, x1, [sp, #(8 * 2)]
add sp, sp, #(8 * 4)
-ENTRY(__smccc_workaround_1_smc_end)
+1: .org __smccc_workaround_1_smc + __SMCCC_WORKAROUND_1_SMC_SZ
+ .org 1b
+SYM_CODE_END(__smccc_workaround_1_smc)
#endif
--
2.20.1
