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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73B7EC43334 for ; Fri, 15 Jul 2022 10:26:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232501AbiGOK0W (ORCPT ); Fri, 15 Jul 2022 06:26:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231508AbiGOK0T (ORCPT ); Fri, 15 Jul 2022 06:26:19 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 74379796A6 for ; Fri, 15 Jul 2022 03:26:18 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 942BD1474; Fri, 15 Jul 2022 03:26:18 -0700 (PDT) Received: from usa.arm.com (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id C99223F792; Fri, 15 Jul 2022 03:26:16 -0700 (PDT) From: Sudeep Holla To: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Conor Dooley Cc: Sudeep Holla , Vincent Guittot , Dietmar Eggemann , Ionela Voinescu , Pierre Gondois , linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org Subject: [PATCH -next v2 1/2] cacheinfo: Use atomic allocation for percpu cache attributes Date: Fri, 15 Jul 2022 11:26:08 +0100 Message-Id: <20220715102609.2160689-1-sudeep.holla@arm.com> X-Mailer: git-send-email 2.37.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On couple of architectures like RISC-V and ARM64, we need to detect cache attribues quite early during the boot when the secondary CPUs start. So we will call detect_cache_attributes in the atomic context and since use of normal allocation can sleep, we will end up getting "sleeping in the atomic context" bug splat. In order avoid that, move the allocation to use atomic version in preparation to move the actual detection of cache attributes in the CPU hotplug path which is atomic. Cc: Ionela Voinescu Tested-by: Conor Dooley Signed-off-by: Sudeep Holla --- drivers/base/cacheinfo.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Hi Greg, Can you apply these couple of patches directly if and when you are happy with them ? Regards, Sudeep v1->v2: This was added in v2 diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 65d566ff24c4..4b5cd08c5a65 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -356,7 +356,7 @@ int detect_cache_attributes(unsigned int cpu) return -ENOENT; per_cpu_cacheinfo(cpu) = kcalloc(cache_leaves(cpu), - sizeof(struct cacheinfo), GFP_KERNEL); + sizeof(struct cacheinfo), GFP_ATOMIC); if (per_cpu_cacheinfo(cpu) == NULL) { cache_leaves(cpu) = 0; return -ENOMEM; -- 2.37.1