From owner-freebsd-fs@freebsd.org Wed Jun 5 16:53:57 2019 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 98B4D15B32F9 for ; Wed, 5 Jun 2019 16:53:57 +0000 (UTC) (envelope-from asomers@gmail.com) Received: from mail-lf1-f46.google.com (mail-lf1-f46.google.com [209.85.167.46]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 7F77A8ACB6 for ; Wed, 5 Jun 2019 16:53:56 +0000 (UTC) (envelope-from asomers@gmail.com) Received: by mail-lf1-f46.google.com with SMTP id m15so19620605lfh.4 for ; Wed, 05 Jun 2019 09:53:56 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=jYypzL7l6g2FeKGCPxnMtycWbtnzVLrAet2wBlqikuM=; b=jfRA3sL3skB4PEXPCIbI+QJzWGh/JnS2g+HVRBflWnXnfa93O65d0icbsztTV2jM3O aYKoQL3oyLPneCxSi8ozjybq3sD5Zg6ZVpz5VwWiSA2+pW2QePmM6fRCXbWxr0R1iik+ SyqB9p67hGauLHC5kIVAJ/lZv/PlW7SEYMYQsnronL+3nq6BkTmcB6pxHfmDLTjTcux0 Q8EA9tSofDbO8nJjQepOnAeHbXbEU/mNMrvjq59XRy17fUrJBYALV7ar1XpU/ujUcRP5 I0wv7dAuQtIX3DR31nBlzukvu5J3TJVgbpjlylSN66XU/ArgnuNV1hl0BC8GoPZGn7f5 QVyg== X-Gm-Message-State: APjAAAXXIFKHtUXcfCFUaPzwT49v4cwU0Gz569p8sW+6fiiv/bh/lxsv LYgez8nBoM0YQ71hdKHuu2DTvF8iY6tnHoRZtSp3Ag== X-Google-Smtp-Source: APXvYqyOAprPhtMIyYdIQ3KY9LqmyuML4g+hjVFleoYIKEhaNEzqM2u0DRZ5xIVdb8YKevEgktlYPdLuSgP3bMv8C+c= X-Received: by 2002:ac2:5324:: with SMTP id f4mr3683722lfh.156.1559752186686; Wed, 05 Jun 2019 09:29:46 -0700 (PDT) MIME-Version: 1.0 From: Alan Somers Date: Wed, 5 Jun 2019 10:29:35 -0600 Message-ID: Subject: Regression test for vn_io_fault To: freebsd-fs Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 7F77A8ACB6 X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; spf=pass (mx1.freebsd.org: domain of asomers@gmail.com designates 209.85.167.46 as permitted sender) smtp.mailfrom=asomers@gmail.com X-Spamd-Result: default: False [-3.94 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; RCVD_COUNT_TWO(0.00)[2]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:209.85.128.0/17]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-fs@freebsd.org]; DMARC_NA(0.00)[freebsd.org]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_TRACE(0.00)[0:+]; TO_DN_ALL(0.00)[]; MX_GOOD(-0.01)[cached: alt3.gmail-smtp-in.l.google.com]; NEURAL_HAM_SHORT(-0.65)[-0.651,0]; RCVD_IN_DNSWL_NONE(0.00)[46.167.85.209.list.dnswl.org : 127.0.5.0]; RCVD_TLS_LAST(0.00)[]; FORGED_SENDER(0.30)[asomers@freebsd.org,asomers@gmail.com]; R_DKIM_NA(0.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:209.85.128.0/17, country:US]; FROM_NEQ_ENVFROM(0.00)[asomers@freebsd.org,asomers@gmail.com]; IP_SCORE(-1.28)[ip: (-0.63), ipnet: 209.85.128.0/17(-3.39), asn: 15169(-2.30), country: US(-0.06)]; TO_DOM_EQ_FROM_DOM(0.00)[] X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Jun 2019 16:53:57 -0000 r236321 added vn_io_fault(), a mechanism for avoiding lock order reversals when a process reads from one file into a mmap()ed buffer backed by another file. From the description in the comments of vn_io_fault() it seems like it would be possible to write a reliable test that would trigger the LOR. But I can't find any evidence in svn, or bugzilla of such a test program. None in Phabricator either, which probably wasn't even running when that commit was made. Did anybody ever write a test program? If so, I volunteer to ATFify it. -Alan