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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 4B701C433DF for ; Mon, 3 Aug 2020 22:52:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3BA912073E for ; Mon, 3 Aug 2020 22:52:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="dkPCs+mr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3BA912073E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 920EA8D0119; Mon, 3 Aug 2020 18:52:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8F7338D0081; Mon, 3 Aug 2020 18:52:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 834298D0119; Mon, 3 Aug 2020 18:52:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0178.hostedemail.com [216.40.44.178]) by kanga.kvack.org (Postfix) with ESMTP id 6DBD68D0081 for ; Mon, 3 Aug 2020 18:52:43 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 27AE78248047 for ; Mon, 3 Aug 2020 22:52:43 +0000 (UTC) X-FDA: 77110758606.16.spade92_601865826fa1 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin16.hostedemail.com (Postfix) with ESMTP id E5612100E6903 for ; Mon, 3 Aug 2020 22:52:42 +0000 (UTC) X-HE-Tag: spade92_601865826fa1 X-Filterd-Recvd-Size: 2558 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf43.hostedemail.com (Postfix) with ESMTP for ; Mon, 3 Aug 2020 22:52:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=b+URD2kuuxPvQN0WgLKZwbxYQpwUjRiQmsZqq1/8gQs=; b=dkPCs+mrjBgij3TZqvL8qsr16Y IazgD9Jl2F9O87Yk9A4tJ3yTMOx8XVdgwrulePxCaZb2jkP8S1Lrj/3NnKzYdEBSr8USXuFf0WKNI dmdAqWJlxSyoUoTI5+KddVB5aeVeN/yHmb5JQoirM3m/rbmRarVgyZB2rXMIwJv53dsQt0/vYq9Xm src4tTj+2BwAPXXjIcabkGedEMXvjFGnmj+18v6UaDktuwbWFwl8gDN75XXlZ0D+pEbY562LIK0iP uynQizi3Zc7DMKmZxkZU+bSNGXqbVj3GWaBoSiH57EB8ZyNhkF1DxmKCU9DbhQMj9g/b8vQhwRmLd 5elqjUww==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1k2jJq-0005tT-Au; Mon, 03 Aug 2020 22:52:34 +0000 Date: Mon, 3 Aug 2020 23:52:34 +0100 From: Matthew Wilcox To: Mike Kravetz Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Hugh Dickins , Naoya Horiguchi , "Aneesh Kumar K . V" , Andrea Arcangeli , "Kirill A . Shutemov" , Davidlohr Bueso , Prakash Sangappa , Andrew Morton , stable@vger.kernel.org Subject: Re: [PATCH] hugetlbfs: remove call to huge_pte_alloc without i_mmap_rwsem Message-ID: <20200803225234.GD23808@casper.infradead.org> References: <20200803224335.55794-1-mike.kravetz@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200803224335.55794-1-mike.kravetz@oracle.com> X-Rspamd-Queue-Id: E5612100E6903 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Aug 03, 2020 at 03:43:35PM -0700, Mike Kravetz wrote: > Commit c0d0381ade79 ("hugetlbfs: use i_mmap_rwsem for more pmd sharing > synchronization") requires callers of huge_pte_alloc to hold i_mmap_rwsem > in at least read mode. This is because the explicit locking in > huge_pmd_share (called by huge_pte_alloc) was removed. When restructuring > the code, the call to huge_pte_alloc in the else block at the beginning > of hugetlb_fault was missed. Should we have a call to mmap_assert_locked() in huge_pte_alloc(), at least the generic one?