From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linutronix.de (146.0.238.70:993) by crypto-ml.lab.linutronix.de with IMAP4-SSL for ; 10 Dec 2018 22:36:50 -0000 Received: from mga06.intel.com ([134.134.136.31]) by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1gWPkY-00014B-PB for speck@linutronix.de; Mon, 10 Dec 2018 18:53:48 +0100 From: Andi Kleen Subject: [MODERATED] [PATCH v2 8/8] MDSv2 2 Date: Mon, 10 Dec 2018 09:53:40 -0800 Message-Id: <7064b44e4325ce4c238666bd9d5eee4f31eaab19.1544464266.git.ak@linux.intel.com> In-Reply-To: References: In-Reply-To: References: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit MIME-Version: 1.0 To: speck@linutronix.de Cc: Andi Kleen List-ID: Clear buffers on kernel exit for MDS mitigation on 32bit kernels. Signed-off-by: Andi Kleen --- arch/x86/entry/entry_32.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index d309f30cf7af..de03a0d8426c 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -921,6 +921,8 @@ ENTRY(entry_SYSENTER_32) popl %edi /* pt_regs->di */ popl %ebp /* pt_regs->bp */ + EXIT_MDS + /* Switch to entry stack */ movl %eax, %esp @@ -1006,10 +1008,12 @@ ENTRY(entry_INT80_32) restore_all: TRACE_IRQS_IRET + EXIT_MDS SWITCH_TO_ENTRY_STACK .Lrestore_all_notrace: CHECK_AND_APPLY_ESPFIX .Lrestore_nocheck: + /* Switch back to user CR3 */ SWITCH_TO_USER_CR3 scratch_reg=%eax @@ -1028,6 +1032,7 @@ restore_all: restore_all_kernel: TRACE_IRQS_IRET PARANOID_EXIT_TO_KERNEL_MODE + EXIT_MDS BUG_IF_WRONG_CR3 RESTORE_REGS 4 jmp .Lirq_return -- 2.17.2