From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.wl.linuxfoundation.org ([198.145.29.98]:54202 "EHLO mail.wl.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726289AbeLPUrn (ORCPT ); Sun, 16 Dec 2018 15:47:43 -0500 Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 32A5328800 for ; Sun, 16 Dec 2018 20:47:43 +0000 (UTC) From: bugzilla-daemon@bugzilla.kernel.org To: linux-ext4@vger.kernel.org Subject: [Bug 201631] WARNING: CPU: 11 PID: 29593 at fs/ext4/inode.c:3927 .ext4_set_page_dirty+0x70/0xb0 Date: Sun, 16 Dec 2018 20:47:42 +0000 Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-ext4-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=201631 --- Comment #11 from Benjamin Herrenschmidt (benh@kernel.crashing.org) --- Jan, I don't know for sure what problems triggers it here, but there definitely is a HW bug on POWER9 with the "NestMMU" (the MMU that services coprocessors and the nvlink), which can cause a dirty bit to be set on a read-only PTE if it races with the PTE update & invalidation. It was "assumed" this was ok. If not I don't know how to work around it. However, at least in the above cases, I don't see how we would be setting dirty if we don't have RW access permission. A PowerMac G5 uses the hash MMU, we set dirty atomically with checking the PTE permission when hashing a PTE in. -- You are receiving this mail because: You are watching the assignee of the bug.