From owner-svn-src-head@freebsd.org Fri Mar 20 11:51:09 2020 Return-Path: Delivered-To: svn-src-head@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 7D5EA264162; Fri, 20 Mar 2020 11:51:09 +0000 (UTC) (envelope-from alfredo@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48kMYS73NFz3JZD; Fri, 20 Mar 2020 11:51:08 +0000 (UTC) (envelope-from alfredo@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id ED28123228; Fri, 20 Mar 2020 11:51:08 +0000 (UTC) (envelope-from alfredo@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 02KBp8Gg012159; Fri, 20 Mar 2020 11:51:08 GMT (envelope-from alfredo@FreeBSD.org) Received: (from alfredo@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 02KBp8Sd012158; Fri, 20 Mar 2020 11:51:08 GMT (envelope-from alfredo@FreeBSD.org) Message-Id: <202003201151.02KBp8Sd012158@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: alfredo set sender to alfredo@FreeBSD.org using -f From: "Alfredo Dal'Ava Junior" Date: Fri, 20 Mar 2020 11:51:08 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r359160 - head/sys/powerpc/powerpc X-SVN-Group: head X-SVN-Commit-Author: alfredo X-SVN-Commit-Paths: head/sys/powerpc/powerpc X-SVN-Commit-Revision: 359160 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Mar 2020 11:51:09 -0000 Author: alfredo Date: Fri Mar 20 11:51:08 2020 New Revision: 359160 URL: https://svnweb.freebsd.org/changeset/base/359160 Log: [PowerPC] fix panic reading /dev/kmem on !DMAP machines This fixes /dev/kmem causing panic on machines not using DMAP. Found when running libkvm Kyua test case on QEMU VM with no Huge Pages support. Reviewed by: jhibbits, luporl Approved by: jhibbits (mentor) Sponsored by: Eldorado Research Institute (eldorado.org.br) Differential Revision: https://reviews.freebsd.org/D23776 Modified: head/sys/powerpc/powerpc/mem.c Modified: head/sys/powerpc/powerpc/mem.c ============================================================================== --- head/sys/powerpc/powerpc/mem.c Fri Mar 20 05:12:16 2020 (r359159) +++ head/sys/powerpc/powerpc/mem.c Fri Mar 20 11:51:08 2020 (r359160) @@ -98,9 +98,11 @@ memrw(struct cdev *dev, struct uio *uio, int flags) struct vm_page m; vm_page_t marr; vm_size_t cnt; + ssize_t orig_resid; cnt = 0; error = 0; + orig_resid = uio->uio_resid; while (uio->uio_resid > 0 && !error) { iov = uio->uio_iov; @@ -137,7 +139,8 @@ kmem_direct_mapped: off = v & PAGE_MASK; else if (dev2unit(dev) == CDEV_MINOR_KMEM) { va = uio->uio_offset; - if ((va < VM_MIN_KERNEL_ADDRESS) || (va > virtual_end)) { + if (hw_direct_map && + ((va < VM_MIN_KERNEL_ADDRESS) || (va > virtual_end))) { v = DMAP_TO_PHYS(va); goto kmem_direct_mapped; } @@ -151,24 +154,34 @@ kmem_direct_mapped: off = v & PAGE_MASK; * so that we don't create any zero-fill pages. */ - for (; va < eva; va += PAGE_SIZE) - if (pmap_extract(kernel_pmap, va) == 0) - return (EFAULT); + for (; va < eva; va += PAGE_SIZE) { + if (pmap_extract(kernel_pmap, va) == 0) { + error = EFAULT; + break; + } + } + if (error != 0) + break; prot = (uio->uio_rw == UIO_READ) ? VM_PROT_READ : VM_PROT_WRITE; va = uio->uio_offset; - if (kernacc((void *) va, iov->iov_len, prot) - == FALSE) - return (EFAULT); + if (((va >= VM_MIN_KERNEL_ADDRESS) && (va <= virtual_end)) && + !kernacc((void *) va, iov->iov_len, prot)) { + error = EFAULT; + break; + } error = uiomove((void *)va, iov->iov_len, uio); - - continue; } } - + /* + * Don't return error if any byte was written. Read and write + * can return error only if no i/o was performed. + */ + if (uio->uio_resid != orig_resid) + error = 0; return (error); }