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Harding" , Kees Cook Subject: Re: [RFC PATCH v2] mm: slub: print kernel addresses in slub debug messages Message-ID: <20190809142617.GO5482@bombadil.infradead.org> References: <20190809010837.24166-1-miles.chen@mediatek.com> <20190809024644.GL5482@bombadil.infradead.org> <1565359918.12824.20.camel@mtkswgap22> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1565359918.12824.20.camel@mtkswgap22> User-Agent: Mutt/1.11.4 (2019-03-13) 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 Fri, Aug 09, 2019 at 10:11:58PM +0800, Miles Chen wrote: > On Thu, 2019-08-08 at 19:46 -0700, Matthew Wilcox wrote: > > On Fri, Aug 09, 2019 at 09:08:37AM +0800, miles.chen@mediatek.com wrote: > > > INFO: Slab 0x(____ptrval____) objects=25 used=10 fp=0x(____ptrval____) > > > > ... you don't have any randomness on your platform? > > We have randomized base on our platforms. Look at initialize_ptr_random(). If you have randomness, then you get a siphash_1u32() of the address. With no randomness, you get this ___ptrval___ string instead.