From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f72.google.com (mail-pg0-f72.google.com [74.125.83.72]) by kanga.kvack.org (Postfix) with ESMTP id 2A0C86B0003 for ; Tue, 20 Feb 2018 15:54:50 -0500 (EST) Received: by mail-pg0-f72.google.com with SMTP id q15so2430679pgv.2 for ; Tue, 20 Feb 2018 12:54:50 -0800 (PST) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id b4-v6si335709plb.648.2018.02.20.12.54.48 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 20 Feb 2018 12:54:49 -0800 (PST) Date: Tue, 20 Feb 2018 12:54:42 -0800 From: Matthew Wilcox Subject: Re: [PATCH 3/6] struct page: add field for vm_struct Message-ID: <20180220205442.GA15973@bombadil.infradead.org> References: <20180211031920.3424-1-igor.stoppa@huawei.com> <20180211031920.3424-4-igor.stoppa@huawei.com> <20180211211646.GC4680@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Igor Stoppa Cc: rdunlap@infradead.org, corbet@lwn.net, keescook@chromium.org, mhocko@kernel.org, labbott@redhat.com, jglisse@redhat.com, hch@infradead.org, cl@linux.com, linux-security-module@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com On Tue, Feb 20, 2018 at 09:53:30PM +0200, Igor Stoppa wrote: > The patch relies on the function vmalloc_to_page ... which will return > NULL when applied to huge mappings, while the original implementation > will still work. Huh? vmalloc_to_page() should work for huge mappings... > It was found while testing on a configuration with framebuffer. ... ah. You tried to use vmalloc_to_page() on something which wasn't backed by a struct page. That's *supposed* to return NULL, but my guess is that after this patch it returned garbage. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org