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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 082DDC5517A for ; Tue, 27 Oct 2020 15:13:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD2992225C for ; Tue, 27 Oct 2020 15:13:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603811620; bh=3w4MIXeh8IKYH+mUDyfUlU+z15dNC+PVjEr1TiFW/rw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=JUQ5ZgRS2/xZ0mH0qKUUMpuwLaqMjl6BSlowsJZYiVGix8yABCmrp2SxjYybAnWt2 KqFcbaqcrcERyuZ9683/mbKZ5vxL3p8ML0k61Uw043H9a25M+QKpBFA+J3XKQIpsEw r8DjiIl5ZOgL56pI6J0/7s7MLPkkkxGyhtRgBeso= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1794784AbgJ0PNc (ORCPT ); Tue, 27 Oct 2020 11:13:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:40328 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1792705AbgJ0PGJ (ORCPT ); Tue, 27 Oct 2020 11:06:09 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7529321707; Tue, 27 Oct 2020 15:06:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603811169; bh=3w4MIXeh8IKYH+mUDyfUlU+z15dNC+PVjEr1TiFW/rw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UPHhYJpbLEL2XuKUL5uUOPFTPHTPZmQOqQ7v2f951imaXFzAXm9Wmj/vM4oJrhsC9 sGfvWIWJEsJVK1CKNrjjw2i49UJustN3+0dyMQLu+8eUg86ZgaG3vUfcE7Ksf8WJI9 M0S/tAuYQ5GTJm/LtzxJGayAuhO9MRRIVxd9ZSt8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Piggin , Michael Ellerman , Sasha Levin Subject: [PATCH 5.8 397/633] powerpc/64: fix irq replay missing preempt Date: Tue, 27 Oct 2020 14:52:20 +0100 Message-Id: <20201027135541.336660495@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027135522.655719020@linuxfoundation.org> References: <20201027135522.655719020@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nicholas Piggin [ Upstream commit 903fd31d3212ab72d564c68f6cfb5d04db68773e ] Prior to commit 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C"), replayed interrupts returned by the regular interrupt exit code, which performs preemption in case an interrupt had set need_resched. This logic was missed by the conversion. Adding preempt_disable/enable around the interrupt replay and final irq enable will reschedule if needed. Fixes: 3282a3da25bd ("powerpc/64: Implement soft interrupt replay in C") Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200915114650.3980244-1-npiggin@gmail.com Signed-off-by: Sasha Levin --- arch/powerpc/kernel/irq.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 05b1cc0e009e4..297ee79febc6c 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -368,6 +368,12 @@ notrace void arch_local_irq_restore(unsigned long mask) } } + /* + * Disable preempt here, so that the below preempt_enable will + * perform resched if required (a replayed interrupt may set + * need_resched). + */ + preempt_disable(); irq_soft_mask_set(IRQS_ALL_DISABLED); trace_hardirqs_off(); @@ -377,6 +383,7 @@ notrace void arch_local_irq_restore(unsigned long mask) trace_hardirqs_on(); irq_soft_mask_set(IRQS_ENABLED); __hard_irq_enable(); + preempt_enable(); } EXPORT_SYMBOL(arch_local_irq_restore); -- 2.25.1