From patchwork Sat Jul 14 04:50:11 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 10524555 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2AF5160627 for ; Sat, 14 Jul 2018 05:00:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 19231295BF for ; Sat, 14 Jul 2018 05:00:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0D9802959F; Sat, 14 Jul 2018 05:00:48 +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=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable 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 5A95E295AA for ; Sat, 14 Jul 2018 05:00:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730301AbeGNFSZ (ORCPT ); Sat, 14 Jul 2018 01:18:25 -0400 Received: from mga05.intel.com ([192.55.52.43]:36407 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725880AbeGNFSZ (ORCPT ); Sat, 14 Jul 2018 01:18:25 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Jul 2018 22:00:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,350,1526367600"; d="scan'208";a="66866182" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by orsmga003.jf.intel.com with ESMTP; 13 Jul 2018 22:00:09 -0700 Subject: [PATCH v6 08/13] mm, memory_failure: Collect mapping size in collect_procs() From: Dan Williams To: linux-nvdimm@lists.01.org Cc: Naoya Horiguchi , hch@lst.de, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Fri, 13 Jul 2018 21:50:11 -0700 Message-ID: <153154381163.34503.9922261445330906942.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <153154376846.34503.15480221419473501643.stgit@dwillia2-desk3.amr.corp.intel.com> References: <153154376846.34503.15480221419473501643.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-2-gc94f MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In preparation for supporting memory_failure() for dax mappings, teach collect_procs() to also determine the mapping size. Unlike typical mappings the dax mapping size is determined by walking page-table entries rather than using the compound-page accounting for THP pages. Acked-by: Naoya Horiguchi Signed-off-by: Dan Williams --- mm/memory-failure.c | 81 +++++++++++++++++++++++++-------------------------- 1 file changed, 40 insertions(+), 41 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 988f977db3d2..8a81680d00dd 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -174,22 +174,51 @@ int hwpoison_filter(struct page *p) EXPORT_SYMBOL_GPL(hwpoison_filter); /* + * Kill all processes that have a poisoned page mapped and then isolate + * the page. + * + * General strategy: + * Find all processes having the page mapped and kill them. + * But we keep a page reference around so that the page is not + * actually freed yet. + * Then stash the page away + * + * There's no convenient way to get back to mapped processes + * from the VMAs. So do a brute-force search over all + * running processes. + * + * Remember that machine checks are not common (or rather + * if they are common you have other problems), so this shouldn't + * be a performance issue. + * + * Also there are some races possible while we get from the + * error detection to actually handle it. + */ + +struct to_kill { + struct list_head nd; + struct task_struct *tsk; + unsigned long addr; + short size_shift; + char addr_valid; +}; + +/* * Send all the processes who have the page mapped a signal. * ``action optional'' if they are not immediately affected by the error * ``action required'' if error happened in current execution context */ -static int kill_proc(struct task_struct *t, unsigned long addr, - unsigned long pfn, struct page *page, int flags) +static int kill_proc(struct to_kill *tk, unsigned long pfn, int flags) { - short addr_lsb; + struct task_struct *t = tk->tsk; + short addr_lsb = tk->size_shift; int ret; pr_err("Memory failure: %#lx: Killing %s:%d due to hardware memory corruption\n", pfn, t->comm, t->pid); - addr_lsb = compound_order(compound_head(page)) + PAGE_SHIFT; if ((flags & MF_ACTION_REQUIRED) && t->mm == current->mm) { - ret = force_sig_mceerr(BUS_MCEERR_AR, (void __user *)addr, + ret = force_sig_mceerr(BUS_MCEERR_AR, (void __user *)tk->addr, addr_lsb, current); } else { /* @@ -198,7 +227,7 @@ static int kill_proc(struct task_struct *t, unsigned long addr, * This could cause a loop when the user sets SIGBUS * to SIG_IGN, but hopefully no one will do that? */ - ret = send_sig_mceerr(BUS_MCEERR_AO, (void __user *)addr, + ret = send_sig_mceerr(BUS_MCEERR_AO, (void __user *)tk->addr, addr_lsb, t); /* synchronous? */ } if (ret < 0) @@ -235,35 +264,6 @@ void shake_page(struct page *p, int access) EXPORT_SYMBOL_GPL(shake_page); /* - * Kill all processes that have a poisoned page mapped and then isolate - * the page. - * - * General strategy: - * Find all processes having the page mapped and kill them. - * But we keep a page reference around so that the page is not - * actually freed yet. - * Then stash the page away - * - * There's no convenient way to get back to mapped processes - * from the VMAs. So do a brute-force search over all - * running processes. - * - * Remember that machine checks are not common (or rather - * if they are common you have other problems), so this shouldn't - * be a performance issue. - * - * Also there are some races possible while we get from the - * error detection to actually handle it. - */ - -struct to_kill { - struct list_head nd; - struct task_struct *tsk; - unsigned long addr; - char addr_valid; -}; - -/* * Failure handling: if we can't find or can't kill a process there's * not much we can do. We just print a message and ignore otherwise. */ @@ -292,6 +292,7 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, } tk->addr = page_address_in_vma(p, vma); tk->addr_valid = 1; + tk->size_shift = compound_order(compound_head(p)) + PAGE_SHIFT; /* * In theory we don't have to kill when the page was @@ -317,9 +318,8 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, * Also when FAIL is set do a force kill because something went * wrong earlier. */ -static void kill_procs(struct list_head *to_kill, int forcekill, - bool fail, struct page *page, unsigned long pfn, - int flags) +static void kill_procs(struct list_head *to_kill, int forcekill, bool fail, + unsigned long pfn, int flags) { struct to_kill *tk, *next; @@ -342,8 +342,7 @@ static void kill_procs(struct list_head *to_kill, int forcekill, * check for that, but we need to tell the * process anyways. */ - else if (kill_proc(tk->tsk, tk->addr, - pfn, page, flags) < 0) + else if (kill_proc(tk, pfn, flags) < 0) pr_err("Memory failure: %#lx: Cannot send advisory machine check signal to %s:%d\n", pfn, tk->tsk->comm, tk->tsk->pid); } @@ -1012,7 +1011,7 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, * any accesses to the poisoned memory. */ forcekill = PageDirty(hpage) || (flags & MF_MUST_KILL); - kill_procs(&tokill, forcekill, !unmap_success, p, pfn, flags); + kill_procs(&tokill, forcekill, !unmap_success, pfn, flags); return unmap_success; }