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=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 92E60C43603 for ; Tue, 10 Dec 2019 22:10:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 671F22053B for ; Tue, 10 Dec 2019 22:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576015835; bh=PjSB7GqX3KOCz41p7Nnh/t7LH57Zj/kdpWXANMj9RTQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=161uGXtKjcQGiBb2R9SOwFUtOPZ7OCIrMKZUXn9dDQ3sjQwoma5uGAIifVY/TUf3Y NK0mUWN+hPMYyKyUxzKJ31t6kZlENNqDIj9Gso72Ei0mX246+Ux80yWltJl/Oh5cKs H019dn2fOwf7kgFlPet//7YOwUv+bynKSVe/ovjs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730266AbfLJWKa (ORCPT ); Tue, 10 Dec 2019 17:10:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:34812 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728548AbfLJWEK (ORCPT ); Tue, 10 Dec 2019 17:04:10 -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 56BA524654; Tue, 10 Dec 2019 22:04:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576015450; bh=PjSB7GqX3KOCz41p7Nnh/t7LH57Zj/kdpWXANMj9RTQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SvIQTMr91LjNmKY1f6WofvhPP/HyIP/TPpXYke2OQZ0L3nLfKpew4/uMVW+oLMT0X ZOikrToZggG91E9GA4NxO2s7gg2QXtFZzwBV49rCLleGH7DXKoeBLK9eVfDVq/nD48 zFpMMkP/XB5K9nvDcipX9M2OB1j6y8rfued/PZII= 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 4.14 057/130] x86/ioapic: Prevent inconsistent state when moving an interrupt Date: Tue, 10 Dec 2019 17:01:48 -0500 Message-Id: <20191210220301.13262-57-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210220301.13262-1-sashal@kernel.org> References: <20191210220301.13262-1-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 566b7bc5deaa0..2271adbc3c42a 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1690,9 +1690,10 @@ 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; @@ -1729,7 +1730,9 @@ 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