From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:45394 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751881AbeBDLby (ORCPT ); Sun, 4 Feb 2018 06:31:54 -0500 Subject: Patch "powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL" has been added to the 4.4-stable tree To: npiggin@gmail.com, gregkh@linuxfoundation.org, mpe@ellerman.id.au Cc: , From: Date: Sun, 04 Feb 2018 12:08:25 +0100 Message-ID: <15177425052146@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-64-convert-fast_exception_return-to-use-rfi_to_user-kernel.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From a08f828cf47e6c605af21d2cdec68f84e799c318 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Wed, 10 Jan 2018 03:07:15 +1100 Subject: powerpc/64: Convert fast_exception_return to use RFI_TO_USER/KERNEL From: Nicholas Piggin commit a08f828cf47e6c605af21d2cdec68f84e799c318 upstream. Similar to the syscall return path, in fast_exception_return 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 | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -891,7 +891,7 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ACCOUNT_CPU_USER_EXIT(r2, r4) REST_GPR(13, r1) -1: + mtspr SPRN_SRR1,r3 ld r2,_CCR(r1) @@ -904,8 +904,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r3,GPR3(r1) ld r4,GPR4(r1) ld r1,GPR1(r1) + RFI_TO_USER + b . /* prevent speculative execution */ - rfid +1: mtspr SPRN_SRR1,r3 + + ld r2,_CCR(r1) + mtcrf 0xFF,r2 + ld r2,_NIP(r1) + mtspr SPRN_SRR0,r2 + + ld r0,GPR0(r1) + ld r2,GPR2(r1) + ld r3,GPR3(r1) + ld r4,GPR4(r1) + ld r1,GPR1(r1) + RFI_TO_KERNEL b . /* prevent speculative execution */ #endif /* CONFIG_PPC_BOOK3E */ Patches currently in stable-queue which might be from npiggin@gmail.com are queue-4.4/powerpc-64s-simple-rfi-macro-conversions.patch queue-4.4/powerpc-64-add-macros-for-annotating-the-destination-of-rfid-hrfid.patch queue-4.4/powerpc-64s-allow-control-of-rfi-flush-via-debugfs.patch queue-4.4/powerpc-64s-convert-slb_miss_common-to-use-rfi_to_user-kernel.patch queue-4.4/powerpc-64-convert-the-syscall-exit-path-to-use-rfi_to_user-kernel.patch queue-4.4/powerpc-64s-add-support-for-rfi-flush-of-l1-d-cache.patch queue-4.4/powerpc-64-convert-fast_exception_return-to-use-rfi_to_user-kernel.patch