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 67D5DC433EF for ; Fri, 3 Dec 2021 08:30:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379197AbhLCIdd (ORCPT ); Fri, 3 Dec 2021 03:33:33 -0500 Received: from smtp-out2.suse.de ([195.135.220.29]:43908 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244052AbhLCIdb (ORCPT ); Fri, 3 Dec 2021 03:33:31 -0500 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id CF2341FD3C; Fri, 3 Dec 2021 08:30:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1638520206; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Paxz2PbJ3ABf+QoTLmxZAgh9n+0xzk9SrTohSl7pwkk=; b=kSucru1oKEfVRiHRu1oP/o1hAlmjYzR6N1aqQkXeKPmOgQxONBO1VjrJZQAHUHF5fE52yK MlZRkecJY7d5lWC5Pj5O8+F2xOTZMG+lFeiTFyBp7s+ZshnszmlL2we/O/jv8uGCjB1+HY YbDQFyl2bgCxEWZ+bbn9RmPUJ+qxu2w= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1638520206; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Paxz2PbJ3ABf+QoTLmxZAgh9n+0xzk9SrTohSl7pwkk=; b=DVfinWFywF5kZKWZWEwp8ExveJDu/qnzWEOkQDaS4mxPYupKcKpenuxvsa0c/qmmgyaU66 2teZ3yw2Pff/IBAw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 6883B13CF5; Fri, 3 Dec 2021 08:30:06 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id Di5XF47VqWGRWQAAMHmgww (envelope-from ); Fri, 03 Dec 2021 08:30:06 +0000 Date: Fri, 3 Dec 2021 09:30:05 +0100 From: Jean Delvare To: Sasha Levin Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Jarkko Nikula , ck+kernelbugzilla@bl4ckb0x.de, stephane.poignant@protonmail.com, Wolfram Sang , linux-i2c@vger.kernel.org Subject: Re: [PATCH AUTOSEL 5.15 35/68] i2c: i801: Fix interrupt storm from SMB_ALERT signal Message-ID: <20211203093005.4337dfde@endymion> In-Reply-To: <20211130144707.944580-35-sashal@kernel.org> References: <20211130144707.944580-1-sashal@kernel.org> <20211130144707.944580-35-sashal@kernel.org> Organization: SUSE Linux X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.32; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sasha, On Tue, 30 Nov 2021 09:46:31 -0500, Sasha Levin wrote: > From: Jarkko Nikula > > [ Upstream commit 03a976c9afb5e3c4f8260c6c08a27d723b279c92 ] > > Currently interrupt storm will occur from i2c-i801 after first > transaction if SMB_ALERT signal is enabled and ever asserted. It is > enough if the signal is asserted once even before the driver is loaded > and does not recover because that interrupt is not acknowledged. > > This fix aims to fix it by two ways: > - Add acknowledging for the SMB_ALERT interrupt status > - Disable the SMB_ALERT interrupt on platforms where possible since the > driver currently does not make use for it > > Acknowledging resets the SMB_ALERT interrupt status on all platforms and > also should help to avoid interrupt storm on older platforms where the > SMB_ALERT interrupt disabling is not available. > > For simplicity this fix reuses the host notify feature for disabling and > restoring original register value. > (...) If you are backporting this, then I think you should also include: commit 9b5bf5878138293fb5b14a48a7a17b6ede6bea25 Author: Jean Delvare Date: Tue Nov 9 16:02:57 2021 +0100 i2c: i801: Restore INTREN on unload which is the first half of the fix for the same bug. Jarkko's patch fixes the interrupt storm while the driver is loaded, mine fixes it after the driver is unloaded (or when the device is handed over to the BIOS, at suspend or reboot). -- Jean Delvare SUSE L3 Support