From owner-svn-src-head@freebsd.org Wed May 20 22:05:25 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 29B1C2F6899; Wed, 20 May 2020 22:05:25 +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 49S6J41N1Zz3d16; Wed, 20 May 2020 22:05:23 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id 04KM59th038381 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Thu, 21 May 2020 01:05:12 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 04KM59th038381 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id 04KM593T038379; Thu, 21 May 2020 01:05:09 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 21 May 2020 01:05:09 +0300 From: Konstantin Belousov To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r361302 - in head: share/man/man7 sys/amd64/amd64 sys/i386/i386 sys/x86/include sys/x86/x86 Message-ID: <20200520220509.GA64045@kib.kiev.ua> References: <202005202200.04KM0VbJ014990@repo.freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202005202200.04KM0VbJ014990@repo.freebsd.org> 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: 49S6J41N1Zz3d16 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 [2.75 / 15.00]; RCVD_TLS_ALL(0.00)[]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; FREEMAIL_FROM(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; TO_DN_NONE(0.00)[]; HAS_XAW(0.00)[]; R_SPF_SOFTFAIL(0.00)[~all]; NEURAL_SPAM_MEDIUM(0.96)[0.959]; NEURAL_SPAM_SHORT(0.85)[0.849]; NEURAL_SPAM_LONG(0.94)[0.939]; 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]; FREEMAIL_ENVFROM(0.00)[gmail.com]; DMARC_POLICY_SOFTFAIL(0.10)[gmail.com : No valid SPF, No valid DKIM,none] X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.33 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: Wed, 20 May 2020 22:05:25 -0000 On Wed, May 20, 2020 at 10:00:31PM +0000, Konstantin Belousov wrote: > Author: kib > Date: Wed May 20 22:00:31 2020 > New Revision: 361302 > URL: https://svnweb.freebsd.org/changeset/base/361302 > > Log: > amd64: Add a knob to flush RSB on context switches if machine has SMEP. > > The flush is needed to prevent cross-process ret2spec, which is not handled > on kernel entry if IBPB is enabled but SMEP is present. > While there, add i386 RSB flush. > > Reported by: Anthony Steinhauser > Reviewed by: markj, Anthony Steinhauser > Discussed with: philip > admbugs: 961 > Sponsored by: The FreeBSD Foundation > MFC after: 1 week https://reviews.freebsd.org/D24868