From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 415BFC432BE for ; Tue, 31 Aug 2021 12:16:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 239C360200 for ; Tue, 31 Aug 2021 12:16:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241566AbhHaMRI (ORCPT ); Tue, 31 Aug 2021 08:17:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241669AbhHaMQ7 (ORCPT ); Tue, 31 Aug 2021 08:16:59 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB8E7C02559A; Tue, 31 Aug 2021 05:13:10 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1630411989; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=SmjNz3mhJ0BePJvvOp7xQW1xRXoh88iEuf6wgamwsMk=; b=hYO+DpL016+ezqsk4QCzP3VZhKw8e1usy0SRkOeZUN6eHOpGUiZnnFwkPC3HaQbsmj3MxL vvXKBKAFS0Yvxa2xHf8CjUhEHds09Xs8zJZJnCAeGIGys5AYmWzKGXowIGq4ccgu/W2IHL QTpk2LdcccX3kdHkPripb5gnf5YMJp9tQNpCQwoyYkC9kUwd7FYng9DA8/iP8uMenp5tFD sDNFV0awiRY791VYFd2C45PfFUh6TpkpRgUP7df0SavZnbN9xyFhzc1x07rH/crVaZUc2B 0HJs/jFtkX5e01tKSqtlCvogiPwBNQ0JFyZoeTj+6yr4iF1uL4N57+YJsH39kg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1630411989; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=SmjNz3mhJ0BePJvvOp7xQW1xRXoh88iEuf6wgamwsMk=; b=4ZnA/q1td52wYvVQktzxACKLVnKy5m0UpBvadm/N2rv25B0KpAhwqtMko1L+c0YUNbV6Al H72RrE5KW0CD7JAA== To: Guenter Roeck , Xiaoming Ni Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, mingo@redhat.com, will@kernel.org, longman@redhat.com, boqun.feng@gmail.com, wangle6@huawei.com, xiaoqian9@huawei.com, shaolexi@huawei.com, linux-acpi@vger.kernel.org, Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Greg Kroah-Hartman Subject: Re: [PATCH] semaphore: Add might_sleep() to down_*() family In-Reply-To: <20210831111322.GA1687117@roeck-us.net> References: <20210809021215.19991-1-nixiaoming@huawei.com> <20210831111322.GA1687117@roeck-us.net> Date: Tue, 31 Aug 2021 14:13:08 +0200 Message-ID: <871r69ersb.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Tue, Aug 31 2021 at 04:13, Guenter Roeck wrote: > Hi, > > On Mon, Aug 09, 2021 at 10:12:15AM +0800, Xiaoming Ni wrote: >> Semaphore is sleeping lock. Add might_sleep() to down*() family >> (with exception of down_trylock()) to detect atomic context sleep. >> >> Previously discussed with Peter Zijlstra, see link: >> https://lore.kernel.org/lkml/20210806082320.GD22037@worktop.programming.kicks-ass.net >> >> Signed-off-by: Xiaoming Ni >> Acked-by: Will Deacon > > This patch results in the following traceback on all arm64 boots with > EFI BIOS. That's what this change was supposed to catch :) > The problem is only seen with CONFIG_ACPI_PPTT=y, and thus only on arm64. The below should fix this. Thanks, tglx --- Subject: drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION() From: Thomas Gleixner Date: Tue, 31 Aug 2021 13:48:34 +0200 DEFINE_SMP_CALL_CACHE_FUNCTION() was usefel before the CPU hotplug rework to ensure that the cache related functions are called on the upcoming CPU because the notifier itself could run on any online CPU. The hotplug state machine guarantees that the callbacks are invoked on the upcoming CPU. So there is no need to have this SMP function call obfuscation. That indirection was missed when the hotplug notifiers were converted. This also solves the problem of ARM64 init_cache_level() invoking ACPI functions which take a semaphore in that context. That's invalid as SMP function calls run with interrupts disabled. Running it just from the callback in context of the CPU hotplug thread solves this. Reported-by: Guenter Roeck Fixes: 8571890e1513 ("arm64: Add support for ACPI based firmware tables") Signed-off-by: Thomas Gleixner --- arch/arm64/kernel/cacheinfo.c | 7 ++----- arch/mips/kernel/cacheinfo.c | 7 ++----- arch/riscv/kernel/cacheinfo.c | 7 ++----- arch/x86/kernel/cpu/cacheinfo.c | 7 ++----- include/linux/cacheinfo.h | 18 ------------------ 5 files changed, 8 insertions(+), 38 deletions(-) --- a/arch/arm64/kernel/cacheinfo.c +++ b/arch/arm64/kernel/cacheinfo.c @@ -43,7 +43,7 @@ static void ci_leaf_init(struct cacheinf this_leaf->type = type; } -static int __init_cache_level(unsigned int cpu) +int init_cache_level(unsigned int cpu) { unsigned int ctype, level, leaves, fw_level; struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); @@ -78,7 +78,7 @@ static int __init_cache_level(unsigned i return 0; } -static int __populate_cache_leaves(unsigned int cpu) +int populate_cache_leaves(unsigned int cpu) { unsigned int level, idx; enum cache_type type; @@ -97,6 +97,3 @@ static int __populate_cache_leaves(unsig } return 0; } - -DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level) -DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves) --- a/arch/mips/kernel/cacheinfo.c +++ b/arch/mips/kernel/cacheinfo.c @@ -17,7 +17,7 @@ do { \ leaf++; \ } while (0) -static int __init_cache_level(unsigned int cpu) +int init_cache_level(unsigned int cpu) { struct cpuinfo_mips *c = ¤t_cpu_data; struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); @@ -74,7 +74,7 @@ static void fill_cpumask_cluster(int cpu cpumask_set_cpu(cpu1, cpu_map); } -static int __populate_cache_leaves(unsigned int cpu) +int populate_cache_leaves(unsigned int cpu) { struct cpuinfo_mips *c = ¤t_cpu_data; struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); @@ -114,6 +114,3 @@ static int __populate_cache_leaves(unsig return 0; } - -DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level) -DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves) --- a/arch/riscv/kernel/cacheinfo.c +++ b/arch/riscv/kernel/cacheinfo.c @@ -113,7 +113,7 @@ static void fill_cacheinfo(struct cachei } } -static int __init_cache_level(unsigned int cpu) +int init_cache_level(unsigned int cpu) { struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); struct device_node *np = of_cpu_device_node_get(cpu); @@ -155,7 +155,7 @@ static int __init_cache_level(unsigned i return 0; } -static int __populate_cache_leaves(unsigned int cpu) +int populate_cache_leaves(unsigned int cpu) { struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); struct cacheinfo *this_leaf = this_cpu_ci->info_list; @@ -187,6 +187,3 @@ static int __populate_cache_leaves(unsig return 0; } - -DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level) -DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves) --- a/arch/x86/kernel/cpu/cacheinfo.c +++ b/arch/x86/kernel/cpu/cacheinfo.c @@ -985,7 +985,7 @@ static void ci_leaf_init(struct cacheinf this_leaf->priv = base->nb; } -static int __init_cache_level(unsigned int cpu) +int init_cache_level(unsigned int cpu) { struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); @@ -1014,7 +1014,7 @@ static void get_cache_id(int cpu, struct id4_regs->id = c->apicid >> index_msb; } -static int __populate_cache_leaves(unsigned int cpu) +int populate_cache_leaves(unsigned int cpu) { unsigned int idx, ret; struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); @@ -1033,6 +1033,3 @@ static int __populate_cache_leaves(unsig return 0; } - -DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level) -DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves) --- a/include/linux/cacheinfo.h +++ b/include/linux/cacheinfo.h @@ -79,24 +79,6 @@ struct cpu_cacheinfo { bool cpu_map_populated; }; -/* - * Helpers to make sure "func" is executed on the cpu whose cache - * attributes are being detected - */ -#define DEFINE_SMP_CALL_CACHE_FUNCTION(func) \ -static inline void _##func(void *ret) \ -{ \ - int cpu = smp_processor_id(); \ - *(int *)ret = __##func(cpu); \ -} \ - \ -int func(unsigned int cpu) \ -{ \ - int ret; \ - smp_call_function_single(cpu, _##func, &ret, true); \ - return ret; \ -} - struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu); int init_cache_level(unsigned int cpu); int populate_cache_leaves(unsigned int cpu);