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Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <20250313233341.1675324-1-dhowells@redhat.com> <20250313233341.1675324-7-dhowells@redhat.com> To: Viacheslav Dubeyko Cc: dhowells@redhat.com, Alex Markuze , "slava@dubeyko.com" , "linux-block@vger.kernel.org" , "idryomov@gmail.com" , "jlayton@kernel.org" , "linux-fsdevel@vger.kernel.org" , "ceph-devel@vger.kernel.org" , "dongsheng.yang@easystack.cn" , "linux-kernel@vger.kernel.org" Subject: Re: [RFC PATCH 06/35] rbd: Use ceph_databuf for rbd_obj_read_sync() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <2370586.1744379306.1@warthog.procyon.org.uk> Content-Transfer-Encoding: quoted-printable Date: Fri, 11 Apr 2025 14:48:26 +0100 Message-ID: <2370587.1744379306@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Viacheslav Dubeyko wrote: > > + dbuf =3D ceph_databuf_req_alloc(1, sizeof(*ondisk), GFP_KERNEL); > = > I am slightly worried about such using of ondisk variable. We have garba= ge as a > value of ondisk pointer on this step yet. And pointer dereferencing coul= d look > confusing here. Also, potentially, compiler and static analysis tools co= uld > complain. I don't see a problem here but anyway I am feeling worried. :) It's a sizeof() construction. We do this all the time: struct fred *p; p =3D kmalloc(sizeof(*p), GFP_KERNEL); David