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=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=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 88FBBC28D19 for ; Wed, 5 Jun 2019 20:32:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63EA32075B for ; Wed, 5 Jun 2019 20:32:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=duncanthrax.net header.i=@duncanthrax.net header.b="SddVfVGp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726502AbfFEUc1 (ORCPT ); Wed, 5 Jun 2019 16:32:27 -0400 Received: from smtp.duncanthrax.net ([89.31.1.170]:36729 "EHLO smtp.duncanthrax.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726528AbfFEUc0 (ORCPT ); Wed, 5 Jun 2019 16:32:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=duncanthrax.net; s=dkim; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=5YGYDUkYdAUpfT0Xr+s3BY3YgmF/shWOzJW/ii8TAfo=; b=SddVfVGpM7HMbFx5sKAqj02f/Q TkkAdt2eh1cGJxCtQ78ECmmYRGq0tCAQKRvFdlYaycLYT+DcFiP8Pnd5Q/TNnHmsjdkXeN3+OW0bm Mh4jVanAHsBd3DjyPXGy+wUb3e3o/Bvf8it4RyYmphhtGGiHRAbCW6dT10TM+DNnt85E=; Received: from [134.3.44.134] (helo=t470p.stackframe.org) by smtp.eurescom.eu with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1hYca8-0004ei-WD; Wed, 05 Jun 2019 22:32:25 +0200 From: Sven Schnelle To: deller@gmx.de Cc: linux-parisc@vger.kernel.org, Sven Schnelle Subject: [PATCH v3 3/6] parisc: add WARN_ON() to clear_fixmap Date: Wed, 5 Jun 2019 22:32:19 +0200 Message-Id: <20190605203222.6194-4-svens@stackframe.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190605203222.6194-1-svens@stackframe.org> References: <20190605203222.6194-1-svens@stackframe.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org Calling clear_fixmap() on an already cleared fixed mapping is a bad thing to do. Add a WARN_ON() to catch such issues. Signed-off-by: Sven Schnelle --- arch/parisc/mm/fixmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/parisc/mm/fixmap.c b/arch/parisc/mm/fixmap.c index c8d41b54fb19..36321bcd75ba 100644 --- a/arch/parisc/mm/fixmap.c +++ b/arch/parisc/mm/fixmap.c @@ -35,6 +35,9 @@ void clear_fixmap(enum fixed_addresses idx) pmd_t *pmd = pmd_offset(pgd, vaddr); pte_t *pte = pte_offset_kernel(pmd, vaddr); + if (WARN_ON(pte_none(*pte))) + return; + pte_clear(&init_mm, vaddr, pte); flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE); -- 2.20.1