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=-2.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, 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 3243DC6778F for ; Wed, 25 Jul 2018 15:48:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF39220882 for ; Wed, 25 Jul 2018 15:48:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=8bytes.org header.i=@8bytes.org header.b="pQwHZjV+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF39220882 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729160AbeGYRAh (ORCPT ); Wed, 25 Jul 2018 13:00:37 -0400 Received: from 8bytes.org ([81.169.241.247]:40166 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728503AbeGYRAg (ORCPT ); Wed, 25 Jul 2018 13:00:36 -0400 Received: by theia.8bytes.org (Postfix, from userid 1000) id A25381EB; Wed, 25 Jul 2018 17:48:19 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=8bytes.org; s=mail-1; t=1532533699; bh=ykRHdAWzkL9irMORgQ3yCGBj8VygOYQR3zKjFy1te0g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pQwHZjV+Hsuy/UbgSaVcSi+/79PBz/0jUAGxon4xT3VYFfAELiMBFwtdhiEFS3k1I SaCSLOQLHLrxHDMlUeepWNNwDcka98DxxWd6GSKwnHJDTz8DMnYK1AoY5op7DdlSTT cZ9Utz6IpkmJIbUo2jerBINddG4/P489XP228bM3tPjkPs5KZ7ZBwj7ybO/DwwIc6Q IBS/g3pxjlfkCDp9HXcX9udwzhbODpSQ03oqGyEwDpOPkaZVS0f979VnKR9JrjSo/X o/NJcYMrEIJJsMJo23ZVTsVHhYvMPTUQT5btkkVSJjUVLTDW7u0yarxS2d4fT0a0MX Ml+mp/m7n1wmw== From: Joerg Roedel To: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Linus Torvalds , Andy Lutomirski , Dave Hansen , Josh Poimboeuf , Juergen Gross , Peter Zijlstra , Borislav Petkov , Jiri Kosina , Boris Ostrovsky , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , Greg KH , Will Deacon , aliguori@amazon.com, daniel.gruss@iaik.tugraz.at, hughd@google.com, keescook@google.com, Andrea Arcangeli , Waiman Long , Pavel Machek , "David H . Gutteridge" , jroedel@suse.de, Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Namhyung Kim , joro@8bytes.org Subject: [PATCH 2/3] Revert "perf/core: Make sure the ring-buffer is mapped in all page-tables" Date: Wed, 25 Jul 2018 17:48:02 +0200 Message-Id: <1532533683-5988-3-git-send-email-joro@8bytes.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1532533683-5988-1-git-send-email-joro@8bytes.org> References: <1532533683-5988-1-git-send-email-joro@8bytes.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joerg Roedel This reverts commit 77754cfa09a6c528c38cbca9ee4cc4f7cf6ad6f2. The patch was necessary to silence a WARN_ON_ONCE(in_nmi()) that triggered in the vmalloc_fault() function when PTI was enabled on x86-32. Faulting in an NMI handler turned out to be safe and the warning in vmalloc_fault() is gone now. So the above patch can be reverted. Signed-off-by: Joerg Roedel --- kernel/events/ring_buffer.c | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index df2d8cf..5d3cf40 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -814,13 +814,6 @@ static void rb_free_work(struct work_struct *work) vfree(base); kfree(rb); - - /* - * FIXME: PAE workaround for vmalloc_fault(): Make sure buffer is - * unmapped in all page-tables. - */ - if (IS_ENABLED(CONFIG_X86_PAE)) - vmalloc_sync_all(); } void rb_free(struct ring_buffer *rb) @@ -847,15 +840,6 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) if (!all_buf) goto fail_all_buf; - /* - * FIXME: PAE workaround for vmalloc_fault(): The buffer is - * accessed in NMI handlers, make sure it is mapped in all - * page-tables in the system so that we don't fault on the range in - * an NMI handler. - */ - if (IS_ENABLED(CONFIG_X86_PAE)) - vmalloc_sync_all(); - rb->user_page = all_buf; rb->data_pages[0] = all_buf + PAGE_SIZE; if (nr_pages) { -- 2.7.4