From owner-dev-commits-src-all@freebsd.org Sun Jun 27 22:23:07 2021 Return-Path: Delivered-To: dev-commits-src-all@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 20E9664A169; Sun, 27 Jun 2021 22:23:07 +0000 (UTC) (envelope-from git@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) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GClcW0Gm0z3JPj; Sun, 27 Jun 2021 22:23:07 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id E640A19ECE; Sun, 27 Jun 2021 22:23:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 15RMN6L5030540; Sun, 27 Jun 2021 22:23:06 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 15RMN69Q030539; Sun, 27 Jun 2021 22:23:06 GMT (envelope-from git) Date: Sun, 27 Jun 2021 22:23:06 GMT Message-Id: <202106272223.15RMN69Q030539@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Chuck Tuffli Subject: git: 91064841d72b - main - bhyve: Fix NVMe iovec construction for large IOs MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: chuck X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 91064841d72b285a146a3f1c32cb447251e062ea Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 27 Jun 2021 22:23:07 -0000 The branch main has been updated by chuck: URL: https://cgit.FreeBSD.org/src/commit/?id=91064841d72b285a146a3f1c32cb447251e062ea commit 91064841d72b285a146a3f1c32cb447251e062ea Author: Chuck Tuffli AuthorDate: 2021-06-27 22:14:52 +0000 Commit: Chuck Tuffli CommitDate: 2021-06-27 22:14:52 +0000 bhyve: Fix NVMe iovec construction for large IOs The UEFI driver included with Rocky Linux 8.4 uncovered an existing bug in the NVMe emulation's construction of iovec's. By default, NVMe data transfer operations use a scatter-gather list in which all entries point to a fixed size memory region. For example, if the Memory Page Size is 4KiB, a 2MiB IO requires 512 entries. Lists themselves are also fixed size (default is 512 entries). Because the list size is fixed, the last entry is special. If the IO requires more than 512 entries, the last entry in the list contains the address of the next list of entries. But if the IO requires exactly 512 entries, the last entry points to data. The NVMe emulation missed this logic and unconditionally treated the last entry as a pointer to the next list. Fix is to check if the remaining data is greater than the page size before using the last entry as a pointer to the next list. PR: 256422 Reported by: dave@syix.com Tested by: jason@tubnor.net MFC after: 5 days Relnotes: yes Reviewed by: imp, grehan Differential Revision: https://reviews.freebsd.org/D30897 --- usr.sbin/bhyve/pci_nvme.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/usr.sbin/bhyve/pci_nvme.c b/usr.sbin/bhyve/pci_nvme.c index 414edabc2b7c..fa316fa285db 100644 --- a/usr.sbin/bhyve/pci_nvme.c +++ b/usr.sbin/bhyve/pci_nvme.c @@ -1976,7 +1976,7 @@ nvme_write_read_blockif(struct pci_nvme_softc *sc, /* PRP2 is pointer to a physical region page list */ while (bytes) { /* Last entry in list points to the next list */ - if (prp_list == last) { + if ((prp_list == last) && (bytes > PAGE_SIZE)) { uint64_t prp = *prp_list; prp_list = paddr_guest2host(vmctx, prp,