From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1420212-1518183649-3-14601338706706226855 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=1518183648; b=L3cC5ocVAMKfqy++Ms0kbVxGdewgdC1TA1QgLN7qoniBQC8 7j8LpLD1SkhSj1kWudTvSQUVTaxz4ZhtulFdD4C3ae42C7jkcKxvkG9Rd6GOKyVW owi7DHHtXJ6l+1Ff/vb+0svpror0HWj/DCep8JCOCzQl8aqdO/wCRFI4y4IBhkb/ ilFF/GyIs1kfsviRJ9P+O8HmjOcoUJgPYYE1EFe91vniKPXGZf3OcIyHsy4MWiVA 20rkhuhcgt/7+abI993kqIxeA1nE7DDSbV48rTzIjyURTwuSt8Q6tmVLWJAWAIqM t2WsvJOcOMMohCR2Ms/w1zgHsKdlzCXMUBWW7Ug== 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=1518183648; bh=gB7IYVRxzOJ+sGLaG2xZ6PwKKu lDoWq9sr8tFpjIuWo=; b=ihAyzwLKjdscVTbUE3/wqmAIIAzh15P6El8pRIVxs9 IIOL15MfZnjTMZjY5QTaYaTlPps6EEFDzGMoQsmFzOtK6oLBgbFaNiUG6Ffa0dDl 89XJgccgIa4p78KmdA0EfebJyT7tOquRqBae53Bmu0NjcxQueQG+5XNjSoV7u+ZC 3EANnwocXS7nHr3etrJNj1aqJqWW59PPHhhLOjPmA3i8tbrcUK0w1COfUjlhwQ2D wIG3o2AAM0xvrQKQGBjpYKUkXu0f2Z6XiONHRP0fJjCkq5Iy/ml3ME0rjwCdHLm5 so4YU+/EJp+0kZscoIJFPbiiY+Iar/0Gj676UEHQZ/nA== ARC-Authentication-Results: i=1; mx5.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: mx5.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 S1751277AbeBINkp (ORCPT ); Fri, 9 Feb 2018 08:40:45 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:48250 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752135AbeBINkn (ORCPT ); Fri, 9 Feb 2018 08:40:43 -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 4.9 04/92] powerpc/64: Convert the syscall exit path to use RFI_TO_USER/KERNEL Date: Fri, 9 Feb 2018 14:38:33 +0100 Message-Id: <20180209133931.554992184@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180209133931.211869118@linuxfoundation.org> References: <20180209133931.211869118@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: 4.9-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 @@ -251,13 +251,23 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_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: