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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 59733C43381 for ; Tue, 12 Mar 2019 17:18:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 23F8E217D8 for ; Tue, 12 Mar 2019 17:18:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552411106; bh=EHodQHAv/IQtKTEYUT+Ji9MDxercDNCJe8JRWtSr36M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PuTSZCZDQ6nL+8od5XKTXj0J+3kys3uNZNr72XJfYQb9UsGmd4nxIwH/KncoGKhv4 Qe+6rhEZPPUhms10R3a3MyxvwwJj38IvJl5CFXdiywfX+q2/ebb3Y0Gtc+QH07bE4W x3Tmh0To1l8gzAslaKDdNDV/+Ix3owQrWIFJptzA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730075AbfCLRSY (ORCPT ); Tue, 12 Mar 2019 13:18:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:34290 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729770AbfCLRRu (ORCPT ); Tue, 12 Mar 2019 13:17:50 -0400 Received: from localhost (unknown [104.133.8.98]) (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 B94FC2183F; Tue, 12 Mar 2019 17:17:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552411069; bh=EHodQHAv/IQtKTEYUT+Ji9MDxercDNCJe8JRWtSr36M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xypoRC199sn9HOaaHQ4wxYLJV/uweh3+J15etd5g0Rf6OXlbUVkCUMZvZUQN6exAS jitkclkUkOqEU5dNOwg+qoukK8MFB2U2+OiwzkDRWOrfmtW5uHjRspfPGjQrnp9aVT W+yxQlvWt0qCEbYSc9RN8YDk3lX3yr++qM30pA4I= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Max Filippov , Sasha Levin Subject: [PATCH 4.9 42/96] xtensa: SMP: fix ccount_timer_shutdown Date: Tue, 12 Mar 2019 10:10:00 -0700 Message-Id: <20190312171037.701374612@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190312171034.530434962@linuxfoundation.org> References: <20190312171034.530434962@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 4fe8713b873fc881284722ce4ac47995de7cf62c ] ccount_timer_shutdown is called from the atomic context in the secondary_start_kernel, resulting in the following BUG: BUG: sleeping function called from invalid context in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1 Preemption disabled at: secondary_start_kernel+0xa1/0x130 Call Trace: ___might_sleep+0xe7/0xfc __might_sleep+0x41/0x44 synchronize_irq+0x24/0x64 disable_irq+0x11/0x14 ccount_timer_shutdown+0x12/0x20 clockevents_switch_state+0x82/0xb4 clockevents_exchange_device+0x54/0x60 tick_check_new_device+0x46/0x70 clockevents_register_device+0x8c/0xc8 clockevents_config_and_register+0x1d/0x2c local_timer_setup+0x75/0x7c secondary_start_kernel+0xb4/0x130 should_never_return+0x32/0x35 Use disable_irq_nosync instead of disable_irq to avoid it. This is safe because the ccount timer IRQ is per-CPU, and once IRQ is masked the ISR will not be called. Signed-off-by: Max Filippov Signed-off-by: Sasha Levin --- arch/xtensa/kernel/time.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/xtensa/kernel/time.c b/arch/xtensa/kernel/time.c index be81e69b25bc..2251a6e0973a 100644 --- a/arch/xtensa/kernel/time.c +++ b/arch/xtensa/kernel/time.c @@ -89,7 +89,7 @@ static int ccount_timer_shutdown(struct clock_event_device *evt) container_of(evt, struct ccount_timer, evt); if (timer->irq_enabled) { - disable_irq(evt->irq); + disable_irq_nosync(evt->irq); timer->irq_enabled = 0; } return 0; -- 2.19.1