From owner-freebsd-hackers@FreeBSD.ORG Wed Apr 14 21:22:24 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 7837C1065670 for ; Wed, 14 Apr 2010 21:22:24 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 48C1F8FC1B for ; Wed, 14 Apr 2010 21:22:24 +0000 (UTC) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id F025546B8B; Wed, 14 Apr 2010 17:22:23 -0400 (EDT) Received: from jhbbsd.localnet (smtp.hudson-trading.com [209.249.190.9]) by bigwig.baldwin.cx (Postfix) with ESMTPA id 4B2328A01F; Wed, 14 Apr 2010 17:22:23 -0400 (EDT) From: John Baldwin To: freebsd-hackers@freebsd.org Date: Wed, 14 Apr 2010 17:21:00 -0400 User-Agent: KMail/1.12.1 (FreeBSD/7.3-CBSD-20100217; KDE/4.3.1; amd64; ; ) References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message-Id: <201004141721.00254.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0.1 (bigwig.baldwin.cx); Wed, 14 Apr 2010 17:22:23 -0400 (EDT) X-Virus-Scanned: clamav-milter 0.95.1 at bigwig.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-1.8 required=4.2 tests=AWL,BAYES_00 autolearn=ham version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on bigwig.baldwin.cx Cc: Fernando =?iso-8859-1?q?Apestegu=EDa?= Subject: Re: Understanding proc_rwmem X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Apr 2010 21:22:24 -0000 On Wednesday 14 April 2010 4:22:56 pm Fernando Apestegu=EDa wrote: > Hi all, >=20 > I'm trying to read process memory other than the current process in > kernel. I was told to use the proc_rwmem function, however I can't get > it working properly. At first, I'm trying to read how many elements > the environment variables vector has. To do this I tried this from a > linprocfs filler function: >=20 >=20 > struct iovec iov; > struct uio tmp_uio; > struct ps_strings *pss; > int ret_code; >=20 > buff =3D malloc(sizeof(struct ps_strings), M_TEMP, M_WAITOK); > memset(buff, 0, sizeof(struct ps_strings)); >=20 > PROC_LOCK_ASSERT(td->td_proc, MA_NOTOWNED); > iov.iov_base =3D (caddr_t) buff; > iov.iov_len =3D sizeof(struct ps_strings); > tmp_uio.uio_iov =3D &iov; > tmp_uio.uio_iovcnt =3D 1; > tmp_uio.uio_offset =3D (off_t)(p->p_sysent->sv_psstrings); > tmp_uio.uio_resid =3D sizeof(struct ps_strings); > tmp_uio.uio_segflg =3D UIO_USERSPACE; > tmp_uio.uio_rw =3D UIO_READ; > tmp_uio.uio_td =3D td; > ret_code =3D proc_rwmem(td->td_proc, &tmp_uio); I think you want to use 'p' instead of 'td->td_proc' here. As it is you ar= e=20 reading from the current process instead of the target process I believe. =2D-=20 John Baldwin