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 364DDCA0FE1 for ; Thu, 31 Aug 2023 23:08:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347745AbjHaXIe (ORCPT ); Thu, 31 Aug 2023 19:08:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233548AbjHaXId (ORCPT ); Thu, 31 Aug 2023 19:08:33 -0400 Received: from mail-oa1-x33.google.com (mail-oa1-x33.google.com [IPv6:2001:4860:4864:20::33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22426FD; Thu, 31 Aug 2023 16:08:30 -0700 (PDT) Received: by mail-oa1-x33.google.com with SMTP id 586e51a60fabf-1c4c5375329so879411fac.2; Thu, 31 Aug 2023 16:08:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1693523309; x=1694128109; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=hAkL29w30IBhvvJdHJX9nCTc0zMhLdBZUZnVSQ/ZN/4=; b=O4VegZeV/fwj/XtGWWvqZSOoMCF2Wwx77aV5ZjNmQQM7U5p1occ2pJ9nNpAXmames/ O0KycrPiK9RpRsl6ZHm9uq6aJTkuaRG+46eMYVp9L1f5TIbTeKyPDd1jDIcALfZOuIGx EK8lPSx1m+fi0Wa1V6ubnB5ePbjdR4sMSfING2T3iKD9wvSv37dMpOhLuaCLqn7HZIPD O/4dZmY7UB8JHyGpmQIUN8llKzbqlg5NAeyHyQOc+ZU9rAEsoz7ljadj4bzGS3HQejLa 5cBEjPAEtMtwgOILpVSHqy2pK5hw6ndWuUhhcIfm2V6UFeHbnkxY6nN3YKbnDdxH36OM 4/Iw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693523309; x=1694128109; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=hAkL29w30IBhvvJdHJX9nCTc0zMhLdBZUZnVSQ/ZN/4=; b=UNjt+1eIgqfS8BXuOUJPfzqMm+aKJ6dYBOAv7YhwM6aYcDRw9aAxFN2armlbbVA+Dv ++mt7mh9w2hwyYHrSqAB4Xi+2Zo6/Qz8O5LatyI+Gq8NxidgNtWq5sRB2yH1I3VElz8+ SCW79AeFSrNOqNXNUMt57/53cKeCYLLIxqCPx/OazJwAW/Yn8b+87C9SbHXcYiW1kh7N kgPsmSvDEP+F1i3wyVWNkHqHaxFree5IMfEoS4vi9LQvedUNy2ms567/9so+p2sjFz6S y84rN5ilciVnENxQsqtc4fd0RIvVOl9n0DF5cW1K9IbIhFy3bBWkKG4/ZBe3IysohHGT wcUQ== X-Gm-Message-State: AOJu0Yy/0VtyjllWgYPsbb/AaIhZ1OWH+jfoC8Wvuu2qcot/KgruLDHy SJ1Mdc3Gd6LbAFfhn0Q9q9Y= X-Google-Smtp-Source: AGHT+IH9UFscX0xilqqMkKi9iMSnO4T6uBbGhY42CzpADPjsgKOguQZm/EO+fSGK/CCUfJCr0mruGQ== X-Received: by 2002:a05:6870:b687:b0:1bf:8a8:dfa with SMTP id cy7-20020a056870b68700b001bf08a80dfamr1004284oab.11.1693523309257; Thu, 31 Aug 2023 16:08:29 -0700 (PDT) Received: from [10.67.48.245] ([192.19.223.252]) by smtp.googlemail.com with ESMTPSA id d4-20020a0cdb04000000b0064f378f89a7sm977651qvk.73.2023.08.31.16.08.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 31 Aug 2023 16:08:28 -0700 (PDT) Message-ID: <48812e7c-1bbf-0084-41be-f62d2cc60231@gmail.com> Date: Thu, 31 Aug 2023 16:08:17 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH v1 1/1] serial: 8250_port: Check IRQ data before use Content-Language: en-US To: Andy Shevchenko , Greg Kroah-Hartman , =?UTF-8?Q?Ilpo_J=c3=a4rvinen?= , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org Cc: Jiri Slaby References: <20230831222555.614426-1-andriy.shevchenko@linux.intel.com> From: Florian Fainelli In-Reply-To: <20230831222555.614426-1-andriy.shevchenko@linux.intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/31/23 15:25, Andy Shevchenko wrote: > In case the leaf driver wants to use IRQ polling (irq = 0) and > IIR register shows that an interrupt happened in the 8250 hardware > the IRQ data can be NULL. In such a case we need to skip the wake > event as we came to this path from the timer interrupt and quite > likely system is already awake. I suppose that is fair to say. > > Without this fix we have got an Oops: > > serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A > ... > BUG: kernel NULL pointer dereference, address: 0000000000000010 > RIP: 0010:serial8250_handle_irq+0x7c/0x240 > Call Trace: > ? serial8250_handle_irq+0x7c/0x240 > ? __pfx_serial8250_timeout+0x10/0x10 > > Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting") > Signed-off-by: Andy Shevchenko Reviewed-by: Florian Fainelli Thanks Andy! -- Florian