From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751559AbeAWM2l (ORCPT ); Tue, 23 Jan 2018 07:28:41 -0500 Received: from foss.arm.com ([217.140.101.70]:40626 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751161AbeAWM2g (ORCPT ); Tue, 23 Jan 2018 07:28:36 -0500 From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, ard.biesheuvel@linaro.org, will.deacon@arm.com, mark.rutland@arm.com, marc.zyngier@arm.com, catalin.marinas@arm.com, ckadabi@codeaurora.org, jnair@caviumnetworks.com, Suzuki K Poulose Subject: [PATCH 06/16] arm64: capabilities: Unify the verification Date: Tue, 23 Jan 2018 12:27:59 +0000 Message-Id: <20180123122809.16269-7-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.13.6 In-Reply-To: <20180123122809.16269-1-suzuki.poulose@arm.com> References: <20180123122809.16269-1-suzuki.poulose@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that each capability describes how to treat the conflicts of CPU cap state vs System wide cap state, we can unify the verification logic to a single place. Signed-off-by: Suzuki K Poulose --- arch/arm64/kernel/cpufeature.c | 87 ++++++++++++++++++++++++++---------------- 1 file changed, 54 insertions(+), 33 deletions(-) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 43c7e992d784..79737034a628 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1228,6 +1228,54 @@ static void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities * } /* + * Run through the list of capabilities to check for conflicts. + * Returns "false" on conflicts. + */ +static bool __verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps_list) +{ + bool cpu_has_cap, system_has_cap; + const struct arm64_cpu_capabilities *caps = caps_list; + + for (; caps->matches; caps++) { + cpu_has_cap = __this_cpu_has_cap(caps_list, caps->capability); + system_has_cap = cpus_have_cap(caps->capability); + + if (system_has_cap) { + /* + * Check if the new CPU misses an advertised feature, which is not + * safe to miss. + */ + if (!cpu_has_cap && !cpucap_late_cpu_missing_cap_safe(caps)) + break; + /* + * We have to issue enable() irrespective of whether the CPU + * has it or not, as it is enabeld system wide. It is upto + * the call back to take appropriate action on this CPU. + */ + if (caps->enable) + caps->enable(caps); + } else { + /* + * Check if the CPU has this capability if it isn't safe to + * have when the system doesn't. + */ + if (cpu_has_cap && !cpucap_late_cpu_have_cap_safe(caps)) + break; + } + } + + if (caps->matches) { + pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n", + smp_processor_id(), caps->capability, + caps->desc ? : "no description", + system_has_cap, cpu_has_cap); + return false; + } + + return true; +} + +/* * Check for CPU features that are used in early boot * based on the Boot CPU value. */ @@ -1249,25 +1297,10 @@ verify_local_elf_hwcaps(const struct arm64_cpu_capabilities *caps) } } -static void -verify_local_cpu_features(const struct arm64_cpu_capabilities *caps_list) +static void verify_local_cpu_features(void) { - const struct arm64_cpu_capabilities *caps = caps_list; - for (; caps->matches; caps++) { - if (!cpus_have_cap(caps->capability)) - continue; - /* - * If the new CPU misses an advertised feature, we cannot proceed - * further, park the cpu. - */ - if (!__this_cpu_has_cap(caps_list, caps->capability)) { - pr_crit("CPU%d: missing feature: %s\n", - smp_processor_id(), caps->desc); - cpu_die_early(); - } - if (caps->enable) - caps->enable(caps); - } + if (!__verify_local_cpu_caps(arm64_features)) + cpu_die_early(); } static void verify_sve_features(void) @@ -1294,20 +1327,8 @@ static void verify_sve_features(void) */ static 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(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(); - } - } + if (__verify_local_cpu_caps(arm64_errata)) + cpu_die_early(); } static void update_cpu_errata_workarounds(void) @@ -1331,7 +1352,7 @@ static void __init enable_errata_workarounds(void) static void verify_local_cpu_capabilities(void) { verify_local_cpu_errata_workarounds(); - verify_local_cpu_features(arm64_features); + verify_local_cpu_features(); verify_local_elf_hwcaps(arm64_elf_hwcaps); if (system_supports_32bit_el0()) -- 2.13.6