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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 AF4B5C10F11 for ; Wed, 10 Apr 2019 06:20:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7AAAF217D6 for ; Wed, 10 Apr 2019 06:20:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554877250; bh=8Cem24ody5j9vsJDLEovzkZOF5suymgugjLde+DwsVM=; h=From:To:Cc:Subject:Date:List-ID:From; b=2rCOYMHuRe2Zke5u0aRBiHsStLXjXa32MC+s1hdtQ8166oCwjZoxQPFnGGrabNKLQ y2Kn9F/obOR6KqRZ3qGCRybK3Kwngw/PSunllNEudo/x+TxdfkC+3wDxloDUMGLLZK KHbleITGRxJErHvT9YTk13PiNgNjW63a2mpOxPr4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727715AbfDJGUt (ORCPT ); Wed, 10 Apr 2019 02:20:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:45418 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726909AbfDJGUs (ORCPT ); Wed, 10 Apr 2019 02:20:48 -0400 Received: from localhost.localdomain (unknown [223.93.147.148]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CABF820850; Wed, 10 Apr 2019 06:20:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554877248; bh=8Cem24ody5j9vsJDLEovzkZOF5suymgugjLde+DwsVM=; h=From:To:Cc:Subject:Date:From; b=1Qn96GXGDpzr+Aqgjb5qZzIrw5+tmrBLr0WETqDuAeBz2lNX/bNjqepQNYOelpuu8 T5R8G7tBq4Jec+lNn294RL/hpCoeV3ZRzG5lgi1SeKJTYcFGFlSGVVPnicTDIRk9c6 /v2S9h6PkPC+KSnfD1Jv7RXzluzjSpo2IaloAw2A= From: guoren@kernel.org To: arnd@arndb.de Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Guo Ren Subject: [PATCH] csky: Fixup wrong update_mmu_cache implementation Date: Wed, 10 Apr 2019 14:18:19 +0800 Message-Id: <1554877099-30927-1-git-send-email-guoren@kernel.org> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Guo Ren In our stress test, we found some crash problem caused by: if (!(vma->vm_flags & VM_EXEC)) return; in update_mmu_cache(). Seems current update_mmu_cache implementation is wrong and we retread to the conservative implementation. Also the usage of kmap_atomic in update_mmu_cache is risky, page-virtual may be scheduled out and changed, so we must use preempt_disable & pagefault_disable which is called by kmap_atomic(). Signed-off-by: Guo Ren Cc: Arnd Bergmann --- arch/csky/abiv2/cacheflush.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/arch/csky/abiv2/cacheflush.c b/arch/csky/abiv2/cacheflush.c index d22c95f..5bb887b 100644 --- a/arch/csky/abiv2/cacheflush.c +++ b/arch/csky/abiv2/cacheflush.c @@ -34,10 +34,6 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, { unsigned long addr, pfn; struct page *page; - void *va; - - if (!(vma->vm_flags & VM_EXEC)) - return; pfn = pte_pfn(*pte); if (unlikely(!pfn_valid(pfn))) @@ -47,14 +43,9 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, if (page == ZERO_PAGE(0)) return; - va = page_address(page); - addr = (unsigned long) va; - - if (va == NULL && PageHighMem(page)) - addr = (unsigned long) kmap_atomic(page); + addr = (unsigned long) kmap_atomic(page); cache_wbinv_range(addr, addr + PAGE_SIZE); - if (va == NULL && PageHighMem(page)) - kunmap_atomic((void *) addr); + kunmap_atomic((void *) addr); } -- 2.7.4