From owner-freebsd-stable@freebsd.org Wed Oct 21 14:17:12 2020 Return-Path: Delivered-To: freebsd-stable@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 3F0F344D28F for ; Wed, 21 Oct 2020 14:17:12 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (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 mx1.freebsd.org (Postfix) with ESMTPS id 4CGXcl2WMZz4MpH for ; Wed, 21 Oct 2020 14:17:11 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.16.1/8.16.1) with ESMTPS id 09LEGvsY070320 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Wed, 21 Oct 2020 17:17:00 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 09LEGvsY070320 Received: (from kostik@localhost) by tom.home (8.16.1/8.16.1/Submit) id 09LEGvug070319; Wed, 21 Oct 2020 17:16:57 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Wed, 21 Oct 2020 17:16:57 +0300 From: Konstantin Belousov To: Nick Kostirya Cc: freebsd-stable@freebsd.org Subject: Re: mmap and MAP_STACK Message-ID: <20201021141657.GJ2643@kib.kiev.ua> References: <20201021165311.186bd606@i11.co> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201021165311.186bd606@i11.co> X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on tom.home X-Rspamd-Queue-Id: 4CGXcl2WMZz4MpH X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=gmail.com (policy=none); spf=softfail (mx1.freebsd.org: 2001:470:d5e7:1::1 is neither permitted nor denied by domain of kostikbel@gmail.com) smtp.mailfrom=kostikbel@gmail.com X-Spamd-Result: default: False [-0.17 / 15.00]; ARC_NA(0.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[gmail.com]; NEURAL_HAM_LONG(-0.12)[-0.124]; MIME_GOOD(-0.10)[text/plain]; HAS_XAW(0.00)[]; NEURAL_HAM_MEDIUM(-0.61)[-0.606]; R_SPF_SOFTFAIL(0.00)[~all:c]; NEURAL_SPAM_SHORT(0.56)[0.559]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US]; RCVD_COUNT_TWO(0.00)[2]; MAILMAN_DEST(0.00)[freebsd-stable]; DMARC_POLICY_SOFTFAIL(0.10)[gmail.com : No valid SPF, No valid DKIM,none] X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Oct 2020 14:17:12 -0000 On Wed, Oct 21, 2020 at 04:53:11PM +0300, Nick Kostirya via freebsd-stable wrote: > Hello. > I have question about mmap. > > void *OSMem::AllocateDataArea(size_t &space) > { > // Round up to an integral number of pages. > space = (space + pageSize-1) & ~(pageSize-1); > int fd = -1; // This value is required by FreeBSD. Linux doesn't care > int flags = MAP_PRIVATE | MAP_ANON; > #ifdef MAP_STACK > if (memUsage == UsageStack) flags |= MAP_STACK; // OpenBSD seems to require this > #endif > void *result = mmap(0, space, PROT_READ|PROT_WRITE, flags, fd, 0); > // Convert MAP_FAILED (-1) into NULL > if (result == MAP_FAILED) > return 0; > return result; > } > > > When MAP_STACK is used, "insufficient memory" error occurs. > When MAP_STACK removed, it is all right. > > Please tell me why. Show ktrace/kdump output of the mmap(2) without and with MAP_STACK. Or provide a minimal self-contained C source that demonstrates your issue.