From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227992w0MulRuEWADbu2vHhdFEBaH5d8hpXp2Qf6yQd4mR+72WcCG2MBPdlNpV0AONfc9IS7 ARC-Seal: i=1; a=rsa-sha256; t=1517840374; cv=none; d=google.com; s=arc-20160816; b=WVcZI529aJx8lJxrNZJUC9cOnU5Yyf2XpbeZtZJ1b+LZE4ykoQ/yTggMJQaW41b7sj 2aUTjML1wDlGN7grmfjZKlN5rWEL4K9oxQQxzmONjP/v5ZBgtFfhTqzAg0bFAk9J2jNr xpLjiM8JRxWecm/Ktd+BbAlqxkXPattmPA4arVMuhotr3vx8sewwMonqo5LAG0SMqcan 4a1Y4oG063GM8/a3rHFAkcwo6KjkawR/hpp4/10UOO/8ipqcjG3qJzwyRQhX2WTVrP+D dxhxn8+cSeJeaVqJqh5qLPp9OVTi35PVYzKa9KgB/GEfNb6Y9hZzY8LdYupGl+f8L9QP YaQg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:date:face:references:in-reply-to:to:from:subject :message-id:dkim-signature:arc-authentication-results; bh=d9KNtw49NXtqXIG+2aOIAI5bU0pPu81pe9yeAOuu2ZI=; b=LAU4s69ACeFqblmcSlnVo7w5NEgCg9qbQLS8p+tRsPRtipawlZ8HNRVz4DXijpuZGc OQrNa5018Grnp/jbdKSB3/+BTbJWi+K5NFxr+pzvYtbTiqjPusjl23fI4Vw1IHaBSH8Q BM0CwbGpR+XJ4qHYAmN66zYB9UwcK6nZGzZ3C+5gnIQIMwIuDrZXVBJ9UV9o49bNwQkO bNH1hb3xtPfnMdEzDot1rOXp716+hMYAepWYuEXUnNid+ywj6ST9sI+QlxKxjtOeKUMi eYX3Qkt0AXDAkOZQBVsyzKP2MzzntQedVPXccxLH2thp0lgzDR6Nw26/yMe7CkNR2bC9 hFcg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=twosheds.20170209 header.b=j1L4ms1h; spf=pass (google.com: best guess record for domain of batv+fec07a82e6eb9b7438c0+5279+infradead.org+dwmw2@twosheds.srs.infradead.org designates 2001:8b0:10b:1:21d:7dff:fe04:dbe2 as permitted sender) smtp.mailfrom=BATV+fec07a82e6eb9b7438c0+5279+infradead.org+dwmw2@twosheds.srs.infradead.org Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=twosheds.20170209 header.b=j1L4ms1h; spf=pass (google.com: best guess record for domain of batv+fec07a82e6eb9b7438c0+5279+infradead.org+dwmw2@twosheds.srs.infradead.org designates 2001:8b0:10b:1:21d:7dff:fe04:dbe2 as permitted sender) smtp.mailfrom=BATV+fec07a82e6eb9b7438c0+5279+infradead.org+dwmw2@twosheds.srs.infradead.org Message-ID: <1517840309.31953.153.camel@infradead.org> Subject: Re: [tip:x86/pti] x86/speculation: Use Indirect Branch Prediction Barrier in context switch From: David Woodhouse To: mingo@kernel.org, hpa@zytor.com, tim.c.chen@linux.intel.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, luto@kernel.org, Greg Kroah-Hartman , linux-mm In-Reply-To: References: <1517263487-3708-1-git-send-email-dwmw@amazon.co.uk> Face: 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 Content-Type: multipart/signed; micalg="sha-256"; protocol="application/x-pkcs7-signature"; boundary="=-cOwTiFdsZGvl+8FSjYsf" Date: Mon, 05 Feb 2018 14:18:29 +0000 Mime-Version: 1.0 X-Mailer: Evolution 3.18.5.2-0ubuntu3.2 X-SRS-Rewrite: SMTP reverse-path rewritten from by twosheds.infradead.org. See http://www.infradead.org/rpr.html X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590966106432961445?= X-GMAIL-MSGID: =?utf-8?q?1591570986011062076?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: --=-cOwTiFdsZGvl+8FSjYsf Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2018-01-30 at 14:39 -0800, tip-bot for Tim Chen wrote: > Thanks to the reviewers and Andy Lutomirski for the suggestion of > using ctx_id which got rid of the problem of mm pointer recycling. That one doesn't backport well to 4.9. 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