From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2179907-1518720247-2-15795197718519460657 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518720247; b=lC7zzXmkzo9TuW/sfhSKzTv4AlNMBd6kn+Qt4QAgql3fFP+ v3DLCT7hK73gt5txNMYPtgNUzSwjJR64+oN4oTBAqWYsvuYJGsD3FfQ5di9nwTH9 JcIh9GTxlzecbaOEP+pHbKqmpjZtlkC3GN3BFqN+GCnQl1cyXpDJk8tmNmZvi4Ym z4P9igLg0jFZBehPiPsgTFkxjzKmtcgV9wEZWKxVAI8hQIjxLekDmAMNUUTPgCna +kqk3bljP2YV6qZImaVwS9r+uScqMa81GPPOBdFiTML41SPUppGns0YUJsuVF91H nUQfxkO9Kqz2372Kz42x3ELDArEHpM5yOhq6rnQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1518720247; bh=fa/gcb5jsb4LvJlWOwU2tJLpNw vmws8gZFseG6E5xaw=; b=psFuXSH1ISfMW76+u8fjnVgNFAKU+VbgJVOdjCS/uy nrk1irp52AjNSKsyltXYAsdfFGRWqrYsdljIbLnLi5B1zmgPnEa4kYImE6mYE6Gv +dR3nQBopYpXEMXAB01r1sS+ouHfT+PXmXXRUqFS4xZRQmSf4z4w5cscO8YR46TD e5sq0Wd1xEB/0pjXzDYlOsEMrUVPGEo8n5kO6QlGzSH5S+abeMON9bQgDTHsHKzs /jhZQ00oYrG4DAHYpyL5pKxwqcgVYQtqSvwpXza5jjsp0fOz+aybLp2qx3WlB04l wQveKSx5inENWkK0uwItkAifoE8SEl9E7+V4tErvDCBA== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162622AbeBOSnx (ORCPT ); Thu, 15 Feb 2018 13:43:53 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:50724 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1162408AbeBOPXO (ORCPT ); Thu, 15 Feb 2018 10:23:14 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Piggin , Michael Ellerman Subject: [PATCH 4.4 009/108] powerpc/64: Convert the syscall exit path to use RFI_TO_USER/KERNEL Date: Thu, 15 Feb 2018 16:16:06 +0100 Message-Id: <20180215151223.697415821@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180215151222.267507937@linuxfoundation.org> References: <20180215151222.267507937@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicholas Piggin commit b8e90cb7bc04a509e821e82ab6ed7a8ef11ba333 upstream. In the syscall exit path we may be returning to user or kernel context. We already have a test for that, because we conditionally restore r13. So use that existing test and branch, and bifurcate the return based on that. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/entry_64.S | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -230,13 +230,23 @@ END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECK ACCOUNT_CPU_USER_EXIT(r11, r12) HMT_MEDIUM_LOW_HAS_PPR ld r13,GPR13(r1) /* only restore r13 if returning to usermode */ + ld r2,GPR2(r1) + ld r1,GPR1(r1) + mtlr r4 + mtcr r5 + mtspr SPRN_SRR0,r7 + mtspr SPRN_SRR1,r8 + RFI_TO_USER + b . /* prevent speculative execution */ + + /* exit to kernel */ 1: ld r2,GPR2(r1) ld r1,GPR1(r1) mtlr r4 mtcr r5 mtspr SPRN_SRR0,r7 mtspr SPRN_SRR1,r8 - RFI + RFI_TO_KERNEL b . /* prevent speculative execution */ syscall_error: