From owner-freebsd-net@freebsd.org Tue Jan 28 10:15:11 2020 Return-Path: Delivered-To: freebsd-net@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 89D7B1FD1B9 for ; Tue, 28 Jan 2020 10:15:11 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (mailman.nyi.freebsd.org [IPv6:2610:1c1:1:606c::50:13]) by mx1.freebsd.org (Postfix) with ESMTP id 486Mtl39gxz3DL5 for ; Tue, 28 Jan 2020 10:15:11 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id 6CE8C1FD1B8; Tue, 28 Jan 2020 10:15:11 +0000 (UTC) Delivered-To: net@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 6CAC71FD1B7 for ; Tue, 28 Jan 2020 10:15:11 +0000 (UTC) (envelope-from bugzilla-noreply@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 486Mtl2JQDz3DL4 for ; Tue, 28 Jan 2020 10:15:11 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4A916215C7 for ; Tue, 28 Jan 2020 10:15:11 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 00SAFBu7072200 for ; Tue, 28 Jan 2020 10:15:11 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 00SAFBJU072199 for net@FreeBSD.org; Tue, 28 Jan 2020 10:15:11 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 243392] if_vmx(4): Input buffer corruption Date: Tue, 28 Jan 2020 10:15:11 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 12.1-RELEASE X-Bugzilla-Keywords: needs-qa X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: avg@FreeBSD.org X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: net@FreeBSD.org X-Bugzilla-Flags: mfc-stable12? X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Jan 2020 10:15:11 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D243392 --- Comment #6 from Andriy Gapon --- I probably should open a new bug for my side of the things as my problem ca= n be different from the original problem reported here. But for the moment here is a new bit of information. I tried to gather a little bit more of information with tcpdump and I got a very surprising result. If I run tcpdump on the vmx side, then the copy speed never degrades. If I start copying before starting tcpdump then the speed can degrade, but = as soon as I start tcpdump (on the vmx side) the speed immediately recovers. I have tested that many times with the same result. It seems that enabling bpf changes the packet processing flow and works aro= und whatever problem there is. Does anyone have an idea what that change could be and where to dig further? Thanks! --=20 You are receiving this mail because: You are the assignee for the bug.=