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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 892F6C433F5 for ; Thu, 23 Sep 2021 03:38:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6D0BF6113E for ; Thu, 23 Sep 2021 03:38:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239234AbhIWDkW (ORCPT ); Wed, 22 Sep 2021 23:40:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:40720 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239150AbhIWDkI (ORCPT ); Wed, 22 Sep 2021 23:40:08 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 59EBA61211; Thu, 23 Sep 2021 03:38:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1632368317; bh=R7lS05/W32gsVyE3040Km9s4BjDQi6uL083xRRWgUs8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c26SZeBCpomds+Q8XwVFcWrWpl8FdmgsN0R9KBH4xzctTyVQSthQXdQt5ZqfOq3VK 8b0ztQCVznKw0BHLkYzUrVHc/Fys1Uegg8GjiRJlW3yXCyktsq9Aue3YkRV9/wCoOl jdsZYui1ANcTOCMhl5fy29QYVLwW4JqxTPffPB89AVHvr25rzlmeSKDdXlyJBC/fWr syDIlj7H73PyjrUVLz1cMnIfV2HVNHao6OtwpFmSArH8MM3uzz53Tyh3YEaZaqmABO Awp6KbgE+MKQAETOuOkzV0V3uydx7pTaxcxWADRDPNgkszu/ovHRa1AqxOKOrdBhYE pjJxGz+aucv0Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Hamza Mahfooz , Jeremy Linton , Christoph Hellwig , Sasha Levin , Christoph@vger.kernel.org, m.szyprowski@samsung.com, iommu@lists.linux-foundation.org Subject: [PATCH AUTOSEL 5.14 08/34] dma-debug: prevent an error message from causing runtime problems Date: Wed, 22 Sep 2021 23:37:56 -0400 Message-Id: <20210923033823.1420814-8-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210923033823.1420814-1-sashal@kernel.org> References: <20210923033823.1420814-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hamza Mahfooz [ Upstream commit 510e1a724ab1bf38150be2c1acabb303f98d0047 ] For some drivers, that use the DMA API. This error message can be reached several millions of times per second, causing spam to the kernel's printk buffer and bringing the CPU usage up to 100% (so, it should be rate limited). However, since there is at least one driver that is in the mainline and suffers from the error condition, it is more useful to err_printk() here instead of just rate limiting the error message (in hopes that it will make it easier for other drivers that suffer from this issue to be spotted). Link: https://lkml.kernel.org/r/fd67fbac-64bf-f0ea-01e1-5938ccfab9d0@arm.com Reported-by: Jeremy Linton Signed-off-by: Hamza Mahfooz Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- kernel/dma/debug.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index f2faa13534e5..70519f67556f 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -567,7 +567,8 @@ static void add_dma_entry(struct dma_debug_entry *entry) pr_err("cacheline tracking ENOMEM, dma-debug disabled\n"); global_disable = true; } else if (rc == -EEXIST) { - pr_err("cacheline tracking EEXIST, overlapping mappings aren't supported\n"); + err_printk(entry->dev, entry, + "cacheline tracking EEXIST, overlapping mappings aren't supported\n"); } } -- 2.30.2