Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752985AbeAAO3Q (ORCPT + 1 other); Mon, 1 Jan 2018 09:29:16 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:42678 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752964AbeAAO3N (ORCPT ); Mon, 1 Jan 2018 09:29:13 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dominik Brodowski , Thomas Gleixner , Andy Lutomirski , Borislav Petkov , Dave Hansen , Linus Torvalds , Linus Torvalds , Peter Zijlstra , Ingo Molnar Subject: [PATCH 4.4 62/63] x86/smpboot: Remove stale TLB flush invocations Date: Mon, 1 Jan 2018 15:25:20 +0100 Message-Id: <20180101140053.134381371@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180101140042.456380281@linuxfoundation.org> References: <20180101140042.456380281@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Gleixner commit 322f8b8b340c824aef891342b0f5795d15e11562 upstream. smpboot_setup_warm_reset_vector() and smpboot_restore_warm_reset_vector() invoke local_flush_tlb() for no obvious reason. Digging in history revealed that the original code in the 2.1 era added those because the code manipulated a swapper_pg_dir pagetable entry. The pagetable manipulation was removed long ago in the 2.3 timeframe, but the TLB flush invocations stayed around forever. Remove them along with the pointless pr_debug()s which come from the same 2.1 change. Reported-by: Dominik Brodowski Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Linus Torvalds Cc: Linus Torvalds Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20171230211829.586548655@linutronix.de Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/smpboot.c | 9 --------- 1 file changed, 9 deletions(-) --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -104,14 +104,10 @@ static inline void smpboot_setup_warm_re spin_lock_irqsave(&rtc_lock, flags); CMOS_WRITE(0xa, 0xf); spin_unlock_irqrestore(&rtc_lock, flags); - local_flush_tlb(); - pr_debug("1.\n"); *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) = start_eip >> 4; - pr_debug("2.\n"); *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = start_eip & 0xf; - pr_debug("3.\n"); } static inline void smpboot_restore_warm_reset_vector(void) @@ -119,11 +115,6 @@ static inline void smpboot_restore_warm_ unsigned long flags; /* - * Install writable page 0 entry to set BIOS data area. - */ - local_flush_tlb(); - - /* * Paranoid: Set warm reset code and vector here back * to default values. */