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 99069C43603 for ; Tue, 10 Dec 2019 21:42:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D7A2205C9 for ; Tue, 10 Dec 2019 21:42:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576014167; bh=eQbFqYCDG+MMyMtiZdXRiT12afIA+0Y7URRm3YxhcdQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dsfMddI/SP5F8Zc9SDwMLhZqQcgpPTiiABJB+kuyvob6uQeaCgla40ZgqOXgz2355 9QlRANTTB26ox0Ibgq7v/H9zLOhH5SdXSX9wAg+vCJZORhxlzY+jnl/uOdbJz16lur 81aM1rNwWfsm8JeNghNpUmDKHwNQB8ftpQPWAWrk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728279AbfLJVmq (ORCPT ); Tue, 10 Dec 2019 16:42:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:38504 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728172AbfLJVdw (ORCPT ); Tue, 10 Dec 2019 16:33:52 -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 EB7202073B; Tue, 10 Dec 2019 21:33:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576013631; bh=eQbFqYCDG+MMyMtiZdXRiT12afIA+0Y7URRm3YxhcdQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dazgZCvCb/25mIERW1/CXUkxCRD0SPLbVRvVGkIJiePtu9S581MzePUgOUVhpfX68 dnFYpwaDHigxdzjgQ3n2U7zya34pMjwsFHSx46oXzFG8u5ZnomXKoz3w2pI/FjoAfs sga0cavIkzOjIGNtrbA12IFQwFFyVbtzlEMppQOA= 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 4.19 073/177] x86/ioapic: Prevent inconsistent state when moving an interrupt Date: Tue, 10 Dec 2019 16:30:37 -0500 Message-Id: <20191210213221.11921-73-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210213221.11921-1-sashal@kernel.org> References: <20191210213221.11921-1-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 ab22eded61d25..fa3b85b222e31 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1724,9 +1724,10 @@ 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; @@ -1763,7 +1764,9 @@ 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