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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 4B20CC43603 for ; Tue, 10 Dec 2019 22:34:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1B57D20828 for ; Tue, 10 Dec 2019 22:34:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576017255; bh=dSAmDi5K/TDVYc2keDhij+3vb2QweI89i+JjWfeGopI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uXpO16xABt2uzpAZVD37NCMhCAyVJNFEmRwyAVK2wsHuGYxXq8F2BrSAbqznRy8fF hFm50jcd9qVXO3KVTCzgbdlOT52v2zisvwTZ7jPq43ek3h1VJq2IonrWLKqDbFB2OG eatjeCHbg8m04JoiwkhS4Mblj3glCPemxiJURIy0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730188AbfLJWeN (ORCPT ); Tue, 10 Dec 2019 17:34:13 -0500 Received: from mail.kernel.org ([198.145.29.99]:55012 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730042AbfLJWdy (ORCPT ); Tue, 10 Dec 2019 17:33:54 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DD50424653; Tue, 10 Dec 2019 22:33:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576017233; bh=dSAmDi5K/TDVYc2keDhij+3vb2QweI89i+JjWfeGopI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cPpUtubC2qhv8fpQF6Z+D8KWRlqN6lUckRybfRpN5vMke2Eg8lh6b/A33YEO95DFY 1XvUDLyTddzwvZK1Sdr4lugfDp7+0BY6D6MLdheoRepEv2MRN53WYzqPG84BKRh9KP 25tCDekIIrWXiy85n4ov103y/Och9MBW5VC2UJec= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Thomas Gleixner , Andy Shevchenko , Linus Torvalds , Peter Zijlstra , Sebastian Siewior , Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL 4.4 31/71] x86/ioapic: Prevent inconsistent state when moving an interrupt Date: Tue, 10 Dec 2019 17:32:36 -0500 Message-Id: <20191210223316.14988-31-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210223316.14988-1-sashal@kernel.org> References: <20191210223316.14988-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner [ Upstream commit df4393424af3fbdcd5c404077176082a8ce459c4 ] There is an issue with threaded interrupts which are marked ONESHOT and using the fasteoi handler: if (IS_ONESHOT()) mask_irq(); .... cond_unmask_eoi_irq() chip->irq_eoi(); if (setaffinity_pending) { mask_ioapic(); ... move_affinity(); unmask_ioapic(); } So if setaffinity is pending the interrupt will be moved and then unconditionally unmasked at the ioapic level, which is wrong in two aspects: 1) It should be kept masked up to the point where the threaded handler finished. 2) The physical chip state and the software masked state are inconsistent Guard both the mask and the unmask with a check for the software masked state. If the line is marked masked then the ioapic line is also masked, so both mask_ioapic() and unmask_ioapic() can be skipped safely. Signed-off-by: Thomas Gleixner Cc: Andy Shevchenko Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Sebastian Siewior Fixes: 3aa551c9b4c4 ("genirq: add threaded interrupt handler support") Link: https://lkml.kernel.org/r/20191017101938.321393687@linutronix.de Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- arch/x86/kernel/apic/io_apic.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 4d5e8ff3b5e5c..5e8fc9809da3f 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1710,9 +1710,10 @@ static bool io_apic_level_ack_pending(struct mp_chip_data *data) static inline bool ioapic_irqd_mask(struct irq_data *data) { - /* If we are moving the irq we need to mask it */ + /* If we are moving the IRQ we need to mask it */ if (unlikely(irqd_is_setaffinity_pending(data))) { - mask_ioapic_irq(data); + if (!irqd_irq_masked(data)) + mask_ioapic_irq(data); return true; } return false; @@ -1749,7 +1750,9 @@ static inline void ioapic_irqd_unmask(struct irq_data *data, bool masked) */ if (!io_apic_level_ack_pending(data->chip_data)) irq_move_masked_irq(data); - unmask_ioapic_irq(data); + /* If the IRQ is masked in the core, leave it: */ + if (!irqd_irq_masked(data)) + unmask_ioapic_irq(data); } } #else -- 2.20.1