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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1EB2C433F5 for ; Mon, 28 Mar 2022 11:25:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241286AbiC1L1i (ORCPT ); Mon, 28 Mar 2022 07:27:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57502 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241610AbiC1LYB (ORCPT ); Mon, 28 Mar 2022 07:24:01 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE83D56C3D; Mon, 28 Mar 2022 04:21:19 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2E3E161126; Mon, 28 Mar 2022 11:21:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84CD6C340EC; Mon, 28 Mar 2022 11:21:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648466478; bh=TzN9S2c1jJpI9v8G0EpdcxObJsrqJKiqIfBV48VR++4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n8FvSGM0+snEAWToKQlnvF0Zn7MlCEujW2AOALzcjEOpadw6FpW4/4+WhpQR8GlKl nnRroaqzXrFR/vrFjM91UScFzNxqAEnP72ZImJkbqo61GS2F14FayIAomKNwk/k59/ iJP9qpsULYuw0XZVN5e8c9KeQxKDhPEXnNFrsgLzl0sVdHFiG7jKZKM2zdZ8rwIXca BZU8Ervq477KU6S1afP06RJH7cvsqsqoGozSZiupfdzM0mgn3ESqFuQXY+Aqkd4O5v rK+B4l7kBIgHoEwh8rkPcKjBUA+vxHlb8sw09qmvsZmrKe3WwUqt3NteefSjZwjP6M pHMpe9LvbXlBg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: John David Anglin , Helge Deller , Sasha Levin , James.Bottomley@HansenPartnership.com, svens@stackframe.org, ira.weiny@intel.com, akpm@linux-foundation.org, linux-parisc@vger.kernel.org Subject: [PATCH AUTOSEL 5.16 30/35] parisc: Fix non-access data TLB cache flush faults Date: Mon, 28 Mar 2022 07:20:06 -0400 Message-Id: <20220328112011.1555169-30-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220328112011.1555169-1-sashal@kernel.org> References: <20220328112011.1555169-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: John David Anglin [ Upstream commit f839e5f1cef36ce268950c387129b1bfefdaebc9 ] When a page is not present, we get non-access data TLB faults from the fdc and fic instructions in flush_user_dcache_range_asm and flush_user_icache_range_asm. When these occur, the cache line is not invalidated and potentially we get memory corruption. The problem was hidden by the nullification of the flush instructions. These faults also affect performance. With pa8800/pa8900 processors, there will be 32 faults per 4 KB page since the cache line is 128 bytes. There will be more faults with earlier processors. The problem is fixed by using flush_cache_pages(). It does the flush using a tmp alias mapping. The flush_cache_pages() call in flush_cache_range() flushed too large a range. V2: Remove unnecessary preempt_disable() and preempt_enable() calls. Signed-off-by: John David Anglin Signed-off-by: Helge Deller Signed-off-by: Sasha Levin --- arch/parisc/kernel/cache.c | 28 +--------------------------- 1 file changed, 1 insertion(+), 27 deletions(-) diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c index 94150b91c96f..bce71cefe572 100644 --- a/arch/parisc/kernel/cache.c +++ b/arch/parisc/kernel/cache.c @@ -558,15 +558,6 @@ static void flush_cache_pages(struct vm_area_struct *vma, struct mm_struct *mm, } } -static void flush_user_cache_tlb(struct vm_area_struct *vma, - unsigned long start, unsigned long end) -{ - flush_user_dcache_range_asm(start, end); - if (vma->vm_flags & VM_EXEC) - flush_user_icache_range_asm(start, end); - flush_tlb_range(vma, start, end); -} - void flush_cache_mm(struct mm_struct *mm) { struct vm_area_struct *vma; @@ -581,17 +572,8 @@ void flush_cache_mm(struct mm_struct *mm) return; } - preempt_disable(); - if (mm->context == mfsp(3)) { - for (vma = mm->mmap; vma; vma = vma->vm_next) - flush_user_cache_tlb(vma, vma->vm_start, vma->vm_end); - preempt_enable(); - return; - } - for (vma = mm->mmap; vma; vma = vma->vm_next) flush_cache_pages(vma, mm, vma->vm_start, vma->vm_end); - preempt_enable(); } void flush_cache_range(struct vm_area_struct *vma, @@ -605,15 +587,7 @@ void flush_cache_range(struct vm_area_struct *vma, return; } - preempt_disable(); - if (vma->vm_mm->context == mfsp(3)) { - flush_user_cache_tlb(vma, start, end); - preempt_enable(); - return; - } - - flush_cache_pages(vma, vma->vm_mm, vma->vm_start, vma->vm_end); - preempt_enable(); + flush_cache_pages(vma, vma->vm_mm, start, end); } void -- 2.34.1