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=-15.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 14615C48BDF for ; Tue, 15 Jun 2021 18:16:03 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CC987611CE for ; Tue, 15 Jun 2021 18:16:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC987611CE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:CC:To:Subject:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=xPQdVPTjmT5CfqdqsDk9ydYxH4Hpq8laoN1aTwi3Tm8=; b=W05Gx8vPk5cW21jV7+wKYs795r vNeAxYbY2MeOMa1KMiClS31kdn1SI2ZFishvgGwi9V38hJCRPUp4yYjxcTJvNP+vJb1cBuMszSPvG p29rbFHIQSXLFux9adSk0mrNxCU19UKiHIrwptmEfpgPsapx/QiqI5WDKKtW/7mtEWsKYe5Zz2C7P kEddkuM8M/JEf8OQ6Em3Vq1ErsRAsf1Z8XQtMlJgv/hlt4fEbhkvjwOF/yWFzUgzFPqEUy83UIBOs HZDgN4kK0kmTsAIhzwZ/5yUepY79vIT9KbGvMGurSjRLD4YQDpaPWhkXK32xBnwAiacYtXAwDVIUr SINtEHeA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ltDZd-0022Gk-A0; Tue, 15 Jun 2021 18:14:05 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lt9Fq-000ByJ-6R for linux-arm-kernel@bombadil.infradead.org; Tue, 15 Jun 2021 13:37:23 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:Content-Type :In-Reply-To:MIME-Version:Date:Message-ID:From:References:CC:To:Subject: Sender:Reply-To:Content-ID:Content-Description; bh=meXDxRRx4LxDf0GQT/IAhUqQ5Ay9MXjBR8qzdqnR1og=; b=HFIRgFSxdsm8M392kIYSbihjB0 qFN7pWeAWgGE2dFBgbOCPwiv/7iuQs7PN+iTy9rzm832+mWWUpq5jUnirX5id69nrcviv2qeOMDaB rb52+Qna2vtoIVwXV4GCTW4X7Nk0ktVvdcuM/4QNG/ocJpyFW1v1MtYRFhwZo/o7yAiYLThKIn6/T X6TUTCFEsy02oTgOBWgVi29d613WGnDgvtkTOkyXVbYkLThVGVo7AjpCnIYTH8o9F5HNqqfu+aTCM +bqwIpUc6C59wju3o0L1ga5w5YAy3BOvk/S0XNpAlMCNEbCvnjtwRlj7fcDxb1uffQ9wtpvwVcN+C ZWk/+kiA==; Received: from szxga01-in.huawei.com ([45.249.212.187]) by desiato.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lt798-007lpl-Fl for linux-arm-kernel@lists.infradead.org; Tue, 15 Jun 2021 11:22:27 +0000 Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4G45Ph1HSczXg8K; Tue, 15 Jun 2021 19:17:12 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 15 Jun 2021 19:22:12 +0800 Received: from [127.0.0.1] (10.174.179.0) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 15 Jun 2021 19:22:11 +0800 Subject: Re: [PATCH 1/1] iommu/arm-smmu-v3: remove unnecessary oom message To: Will Deacon CC: Robin Murphy , linux-arm-kernel , Joerg Roedel , iommu References: <20210609125438.14369-1-thunder.leizhen@huawei.com> <20210611103220.GB15274@willie-the-truck> From: "Leizhen (ThunderTown)" Message-ID: <2a0b7f37-156a-775f-ade4-015cade472c6@huawei.com> Date: Tue, 15 Jun 2021 19:22:10 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20210611103220.GB15274@willie-the-truck> Content-Language: en-US X-Originating-IP: [10.174.179.0] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210615_122225_879401_DEDEDF54 X-CRM114-Status: GOOD ( 18.05 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2021/6/11 18:32, Will Deacon wrote: > On Wed, Jun 09, 2021 at 08:54:38PM +0800, Zhen Lei wrote: >> Fixes scripts/checkpatch.pl warning: >> WARNING: Possible unnecessary 'out of memory' message >> >> Remove it can help us save a bit of memory. >> >> Signed-off-by: Zhen Lei >> --- >> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 ++------ >> 1 file changed, 2 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> index 2ddc3cd5a7d1..fd7c55b44881 100644 >> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c >> @@ -2787,10 +2787,8 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) >> void *strtab = smmu->strtab_cfg.strtab; >> >> cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL); >> - if (!cfg->l1_desc) { >> - dev_err(smmu->dev, "failed to allocate l1 stream table desc\n"); >> + if (!cfg->l1_desc) > > What error do you get if devm_kzalloc() fails? I'd like to make sure it's > easy to track down _which_ allocation failed in that case -- does it give > you a line number, for example? When devm_kzalloc() fails, the OOM information is printed. No line number information, but the size(order) and call stack is printed. It doesn't matter which allocation failed, the failure is caused by insufficient system memory rather than the fault of the SMMU driver. Therefore, the current printing is not helpful for locating the problem of insufficient memory. After all, when memory allocation fails, the SMMU driver cannot work at a lower specification. [ 44.126661] swapper/0 invoked oom-killer: gfp_mask=0x40cc0(GFP_KERNEL|__GFP_COMP), order=1, oom_score_adj=0 [ 44.136381] CPU: 26 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc6-00001-g0d973bf828c8 #1 [ 44.144436] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B220.02 03/27/2020 [ 44.153266] Call trace: [ 44.155703] dump_backtrace+0x0/0x1c0 [ 44.159355] show_stack+0x18/0x68 [ 44.162658] dump_stack+0xd8/0x134 [ 44.166047] dump_header+0x44/0x208 [ 44.169524] out_of_memory+0x530/0x580 [ 44.173256] __alloc_pages_slowpath.constprop.120+0x85c/0xac0 [ 44.178976] __alloc_pages+0x238/0x300 [ 44.182709] allocate_slab+0x3bc/0x3d8 [ 44.186440] ___slab_alloc+0x508/0x6b0 [ 44.190172] __slab_alloc.isra.100+0x2c/0x58 [ 44.194422] __kmalloc_node_track_caller+0x138/0x2e8 [ 44.199365] devm_kmalloc+0x58/0x100 [ 44.202926] arm_smmu_device_probe+0x858/0x1150 [ 44.207437] platform_probe+0x68/0xe0 > > Will > > . > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel