From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751104AbdL3VWN (ORCPT ); Sat, 30 Dec 2017 16:22:13 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:35225 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750920AbdL3VWK (ORCPT ); Sat, 30 Dec 2017 16:22:10 -0500 Message-Id: <20171230211829.586548655@linutronix.de> User-Agent: quilt/0.63-1 Date: Sat, 30 Dec 2017 22:13:53 +0100 From: Thomas Gleixner To: LKML Cc: Linus Torvalds , x86@kernel.org, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Borislav Petkov , Dominik Brodowski Subject: [patch 2/3] x86/smpboot: Remove stale tlb flush invocations References: <20171230211351.980176980@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=x86-smpboot--Remove-stale-tlb-flush-invocations.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 aera 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_debugs which come from the same 2.1 change. Reported-by: Dominik Brodowski Signed-off-by: Thomas Gleixner --- arch/x86/kernel/smpboot.c | 9 --------- 1 file changed, 9 deletions(-) --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -128,14 +128,10 @@ 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) @@ -143,11 +139,6 @@ 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. */