From patchwork Tue Jun 4 18:34:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Schnelle X-Patchwork-Id: 10975919 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AD2E03A3F for ; Tue, 4 Jun 2019 18:35:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9C48827BA5 for ; Tue, 4 Jun 2019 18:35:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 900FB286F3; Tue, 4 Jun 2019 18:35:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 188B528455 for ; Tue, 4 Jun 2019 18:34:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725933AbfFDSem (ORCPT ); Tue, 4 Jun 2019 14:34:42 -0400 Received: from smtp.duncanthrax.net ([89.31.1.170]:51206 "EHLO smtp.duncanthrax.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726460AbfFDSem (ORCPT ); Tue, 4 Jun 2019 14:34:42 -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=EVoMMHiVAJoqDnkt5TfQGDGQiJ iLV0jj5v1vHzsMLMK5pUEcwhTB57giD/TaMZv/+j9g+lAC9NrE2TIJppFsnXK9QmMSYtODLwQg7lC pWvGbNduRFECRDG1QYACb9t48wHs73z5Q/yBza1KrFeYRMTNLSMYXUz/tezn78Yx6RHs=; 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 1hYEGe-0002tN-PM; Tue, 04 Jun 2019 20:34:40 +0200 From: Sven Schnelle To: deller@gmx.de Cc: linux-parisc@vger.kernel.org, Sven Schnelle Subject: [PATCH v2 3/6] parisc: add WARN_ON() to clear_fixmap Date: Tue, 4 Jun 2019 20:34:32 +0200 Message-Id: <20190604183435.20175-4-svens@stackframe.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190604183435.20175-1-svens@stackframe.org> References: <20190604183435.20175-1-svens@stackframe.org> MIME-Version: 1.0 Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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);