linux/arch/arm64/kernel/cpu_errata.c
Marc Zyngier e21da1c992 arm64: Relax ARM_SMCCC_ARCH_WORKAROUND_1 discovery
A recent update to the ARM SMCCC ARCH_WORKAROUND_1 specification
allows firmware to return a non zero, positive value to describe
that although the mitigation is implemented at the higher exception
level, the CPU on which the call is made is not affected.

Let's relax the check on the return value from ARCH_WORKAROUND_1
so that we only error out if the returned value is negative.

Fixes: b092201e00 ("arm64: Add ARM_SMCCC_ARCH_WORKAROUND_1 BP hardening support")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-03-09 17:52:07 +00:00

465 lines
12 KiB
C

/*
* Contains CPU specific errata definitions
*
* Copyright (C) 2014 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/types.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/cpufeature.h>
static bool __maybe_unused
is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope)
{
WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
return MIDR_IS_CPU_MODEL_RANGE(read_cpuid_id(), entry->midr_model,
entry->midr_range_min,
entry->midr_range_max);
}
static bool __maybe_unused
is_kryo_midr(const struct arm64_cpu_capabilities *entry, int scope)
{
u32 model;
WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
model = read_cpuid_id();
model &= MIDR_IMPLEMENTOR_MASK | (0xf00 << MIDR_PARTNUM_SHIFT) |
MIDR_ARCHITECTURE_MASK;
return model == entry->midr_model;
}
static bool
has_mismatched_cache_line_size(const struct arm64_cpu_capabilities *entry,
int scope)
{
WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
return (read_cpuid_cachetype() & arm64_ftr_reg_ctrel0.strict_mask) !=
(arm64_ftr_reg_ctrel0.sys_val & arm64_ftr_reg_ctrel0.strict_mask);
}
static int cpu_enable_trap_ctr_access(void *__unused)
{
/* Clear SCTLR_EL1.UCT */
config_sctlr_el1(SCTLR_EL1_UCT, 0);
return 0;
}
#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
#ifdef CONFIG_KVM
extern char __qcom_hyp_sanitize_link_stack_start[];
extern char __qcom_hyp_sanitize_link_stack_end[];
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)
{
void *dst = lm_alias(__bp_harden_hyp_vecs_start + slot * SZ_2K);
int i;
for (i = 0; i < SZ_2K; i += 0x80)
memcpy(dst + i, hyp_vecs_start, hyp_vecs_end - hyp_vecs_start);
flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K);
}
static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
const char *hyp_vecs_start,
const char *hyp_vecs_end)
{
static int last_slot = -1;
static DEFINE_SPINLOCK(bp_lock);
int cpu, slot = -1;
spin_lock(&bp_lock);
for_each_possible_cpu(cpu) {
if (per_cpu(bp_hardening_data.fn, cpu) == fn) {
slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu);
break;
}
}
if (slot == -1) {
last_slot++;
BUG_ON(((__bp_harden_hyp_vecs_end - __bp_harden_hyp_vecs_start)
/ SZ_2K) <= last_slot);
slot = last_slot;
__copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end);
}
__this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
__this_cpu_write(bp_hardening_data.fn, fn);
spin_unlock(&bp_lock);
}
#else
#define __qcom_hyp_sanitize_link_stack_start NULL
#define __qcom_hyp_sanitize_link_stack_end NULL
#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,
const char *hyp_vecs_end)
{
__this_cpu_write(bp_hardening_data.fn, fn);
}
#endif /* CONFIG_KVM */
static void install_bp_hardening_cb(const struct arm64_cpu_capabilities *entry,
bp_hardening_cb_t fn,
const char *hyp_vecs_start,
const char *hyp_vecs_end)
{
u64 pfr0;
if (!entry->matches(entry, SCOPE_LOCAL_CPU))
return;
pfr0 = read_cpuid(ID_AA64PFR0_EL1);
if (cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_CSV2_SHIFT))
return;
__install_bp_hardening_cb(fn, hyp_vecs_start, hyp_vecs_end);
}
#include <uapi/linux/psci.h>
#include <linux/arm-smccc.h>
#include <linux/psci.h>
static void call_smc_arch_workaround_1(void)
{
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
}
static void call_hvc_arch_workaround_1(void)
{
arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
}
static int enable_smccc_arch_workaround_1(void *data)
{
const struct arm64_cpu_capabilities *entry = data;
bp_hardening_cb_t cb;
void *smccc_start, *smccc_end;
struct arm_smccc_res res;
if (!entry->matches(entry, SCOPE_LOCAL_CPU))
return 0;
if (psci_ops.smccc_version == SMCCC_VERSION_1_0)
return 0;
switch (psci_ops.conduit) {
case PSCI_CONDUIT_HVC:
arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_ARCH_WORKAROUND_1, &res);
if ((int)res.a0 < 0)
return 0;
cb = call_hvc_arch_workaround_1;
smccc_start = __smccc_workaround_1_hvc_start;
smccc_end = __smccc_workaround_1_hvc_end;
break;
case PSCI_CONDUIT_SMC:
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_ARCH_WORKAROUND_1, &res);
if ((int)res.a0 < 0)
return 0;
cb = call_smc_arch_workaround_1;
smccc_start = __smccc_workaround_1_smc_start;
smccc_end = __smccc_workaround_1_smc_end;
break;
default:
return 0;
}
install_bp_hardening_cb(entry, cb, smccc_start, smccc_end);
return 0;
}
static void qcom_link_stack_sanitization(void)
{
u64 tmp;
asm volatile("mov %0, x30 \n"
".rept 16 \n"
"bl . + 4 \n"
".endr \n"
"mov x30, %0 \n"
: "=&r" (tmp));
}
static int qcom_enable_link_stack_sanitization(void *data)
{
const struct arm64_cpu_capabilities *entry = data;
install_bp_hardening_cb(entry, qcom_link_stack_sanitization,
__qcom_hyp_sanitize_link_stack_start,
__qcom_hyp_sanitize_link_stack_end);
return 0;
}
#endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */
#define MIDR_RANGE(model, min, max) \
.def_scope = SCOPE_LOCAL_CPU, \
.matches = is_affected_midr_range, \
.midr_model = model, \
.midr_range_min = min, \
.midr_range_max = max
#define MIDR_ALL_VERSIONS(model) \
.def_scope = SCOPE_LOCAL_CPU, \
.matches = is_affected_midr_range, \
.midr_model = model, \
.midr_range_min = 0, \
.midr_range_max = (MIDR_VARIANT_MASK | MIDR_REVISION_MASK)
const struct arm64_cpu_capabilities arm64_errata[] = {
#if defined(CONFIG_ARM64_ERRATUM_826319) || \
defined(CONFIG_ARM64_ERRATUM_827319) || \
defined(CONFIG_ARM64_ERRATUM_824069)
{
/* Cortex-A53 r0p[012] */
.desc = "ARM errata 826319, 827319, 824069",
.capability = ARM64_WORKAROUND_CLEAN_CACHE,
MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x02),
.enable = cpu_enable_cache_maint_trap,
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_819472
{
/* Cortex-A53 r0p[01] */
.desc = "ARM errata 819472",
.capability = ARM64_WORKAROUND_CLEAN_CACHE,
MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x01),
.enable = cpu_enable_cache_maint_trap,
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_832075
{
/* Cortex-A57 r0p0 - r1p2 */
.desc = "ARM erratum 832075",
.capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE,
MIDR_RANGE(MIDR_CORTEX_A57,
MIDR_CPU_VAR_REV(0, 0),
MIDR_CPU_VAR_REV(1, 2)),
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_834220
{
/* Cortex-A57 r0p0 - r1p2 */
.desc = "ARM erratum 834220",
.capability = ARM64_WORKAROUND_834220,
MIDR_RANGE(MIDR_CORTEX_A57,
MIDR_CPU_VAR_REV(0, 0),
MIDR_CPU_VAR_REV(1, 2)),
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_845719
{
/* Cortex-A53 r0p[01234] */
.desc = "ARM erratum 845719",
.capability = ARM64_WORKAROUND_845719,
MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x04),
},
#endif
#ifdef CONFIG_CAVIUM_ERRATUM_23154
{
/* Cavium ThunderX, pass 1.x */
.desc = "Cavium erratum 23154",
.capability = ARM64_WORKAROUND_CAVIUM_23154,
MIDR_RANGE(MIDR_THUNDERX, 0x00, 0x01),
},
#endif
#ifdef CONFIG_CAVIUM_ERRATUM_27456
{
/* Cavium ThunderX, T88 pass 1.x - 2.1 */
.desc = "Cavium erratum 27456",
.capability = ARM64_WORKAROUND_CAVIUM_27456,
MIDR_RANGE(MIDR_THUNDERX,
MIDR_CPU_VAR_REV(0, 0),
MIDR_CPU_VAR_REV(1, 1)),
},
{
/* Cavium ThunderX, T81 pass 1.0 */
.desc = "Cavium erratum 27456",
.capability = ARM64_WORKAROUND_CAVIUM_27456,
MIDR_RANGE(MIDR_THUNDERX_81XX, 0x00, 0x00),
},
#endif
#ifdef CONFIG_CAVIUM_ERRATUM_30115
{
/* Cavium ThunderX, T88 pass 1.x - 2.2 */
.desc = "Cavium erratum 30115",
.capability = ARM64_WORKAROUND_CAVIUM_30115,
MIDR_RANGE(MIDR_THUNDERX, 0x00,
(1 << MIDR_VARIANT_SHIFT) | 2),
},
{
/* Cavium ThunderX, T81 pass 1.0 - 1.2 */
.desc = "Cavium erratum 30115",
.capability = ARM64_WORKAROUND_CAVIUM_30115,
MIDR_RANGE(MIDR_THUNDERX_81XX, 0x00, 0x02),
},
{
/* Cavium ThunderX, T83 pass 1.0 */
.desc = "Cavium erratum 30115",
.capability = ARM64_WORKAROUND_CAVIUM_30115,
MIDR_RANGE(MIDR_THUNDERX_83XX, 0x00, 0x00),
},
#endif
{
.desc = "Mismatched cache line size",
.capability = ARM64_MISMATCHED_CACHE_LINE_SIZE,
.matches = has_mismatched_cache_line_size,
.def_scope = SCOPE_LOCAL_CPU,
.enable = cpu_enable_trap_ctr_access,
},
#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1003
{
.desc = "Qualcomm Technologies Falkor erratum 1003",
.capability = ARM64_WORKAROUND_QCOM_FALKOR_E1003,
MIDR_RANGE(MIDR_QCOM_FALKOR_V1,
MIDR_CPU_VAR_REV(0, 0),
MIDR_CPU_VAR_REV(0, 0)),
},
{
.desc = "Qualcomm Technologies Kryo erratum 1003",
.capability = ARM64_WORKAROUND_QCOM_FALKOR_E1003,
.def_scope = SCOPE_LOCAL_CPU,
.midr_model = MIDR_QCOM_KRYO,
.matches = is_kryo_midr,
},
#endif
#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1009
{
.desc = "Qualcomm Technologies Falkor erratum 1009",
.capability = ARM64_WORKAROUND_REPEAT_TLBI,
MIDR_RANGE(MIDR_QCOM_FALKOR_V1,
MIDR_CPU_VAR_REV(0, 0),
MIDR_CPU_VAR_REV(0, 0)),
},
#endif
#ifdef CONFIG_ARM64_ERRATUM_858921
{
/* Cortex-A73 all versions */
.desc = "ARM erratum 858921",
.capability = ARM64_WORKAROUND_858921,
MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
},
#endif
#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
.enable = enable_smccc_arch_workaround_1,
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
.enable = enable_smccc_arch_workaround_1,
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
.enable = enable_smccc_arch_workaround_1,
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
.enable = enable_smccc_arch_workaround_1,
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR_V1),
.enable = qcom_enable_link_stack_sanitization,
},
{
.capability = ARM64_HARDEN_BP_POST_GUEST_EXIT,
MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR_V1),
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR),
.enable = qcom_enable_link_stack_sanitization,
},
{
.capability = ARM64_HARDEN_BP_POST_GUEST_EXIT,
MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR),
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN),
.enable = enable_smccc_arch_workaround_1,
},
{
.capability = ARM64_HARDEN_BRANCH_PREDICTOR,
MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2),
.enable = enable_smccc_arch_workaround_1,
},
#endif
{
}
};
/*
* The CPU Errata work arounds are detected and applied at boot time
* and the related information is freed soon after. If the new CPU requires
* an errata not detected at boot, fail this CPU.
*/
void verify_local_cpu_errata_workarounds(void)
{
const struct arm64_cpu_capabilities *caps = arm64_errata;
for (; caps->matches; caps++) {
if (cpus_have_cap(caps->capability)) {
if (caps->enable)
caps->enable((void *)caps);
} else if (caps->matches(caps, SCOPE_LOCAL_CPU)) {
pr_crit("CPU%d: Requires work around for %s, not detected"
" at boot time\n",
smp_processor_id(),
caps->desc ? : "an erratum");
cpu_die_early();
}
}
}
void update_cpu_errata_workarounds(void)
{
update_cpu_capabilities(arm64_errata, "enabling workaround for");
}
void __init enable_errata_workarounds(void)
{
enable_cpu_capabilities(arm64_errata);
}