Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754114AbeAAOkJ (ORCPT + 1 other); Mon, 1 Jan 2018 09:40:09 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:44834 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751669AbeAAOkD (ORCPT ); Mon, 1 Jan 2018 09:40:03 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dave Hansen , "Peter Zijlstra (Intel)" , Thomas Gleixner , Andy Lutomirski , Boris Ostrovsky , Borislav Petkov , Brian Gerst , David Laight , Denys Vlasenko , Eduardo Valentin , "H. Peter Anvin" , Josh Poimboeuf , Juergen Gross , Linus Torvalds , Will Deacon , aliguori@amazon.com, daniel.gruss@iaik.tugraz.at, hughd@google.com, keescook@google.com, Ingo Molnar Subject: [PATCH 4.14 025/146] x86/mm: Abstract switching CR3 Date: Mon, 1 Jan 2018 15:36:56 +0100 Message-Id: <20180101140127.501131588@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180101140123.743014891@linuxfoundation.org> References: <20180101140123.743014891@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: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Hansen commit 48e111982cda033fec832c6b0592c2acedd85d04 upstream. In preparation to adding additional PCID flushing, abstract the loading of a new ASID into CR3. [ PeterZ: Split out from big combo patch ] Signed-off-by: Dave Hansen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/mm/tlb.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -100,6 +100,24 @@ static void choose_new_asid(struct mm_st *need_flush = true; } +static void load_new_mm_cr3(pgd_t *pgdir, u16 new_asid, bool need_flush) +{ + unsigned long new_mm_cr3; + + if (need_flush) { + new_mm_cr3 = build_cr3(pgdir, new_asid); + } else { + new_mm_cr3 = build_cr3_noflush(pgdir, new_asid); + } + + /* + * Caution: many callers of this function expect + * that load_cr3() is serializing and orders TLB + * fills with respect to the mm_cpumask writes. + */ + write_cr3(new_mm_cr3); +} + void leave_mm(int cpu) { struct mm_struct *loaded_mm = this_cpu_read(cpu_tlbstate.loaded_mm); @@ -230,7 +248,7 @@ void switch_mm_irqs_off(struct mm_struct if (need_flush) { this_cpu_write(cpu_tlbstate.ctxs[new_asid].ctx_id, next->context.ctx_id); this_cpu_write(cpu_tlbstate.ctxs[new_asid].tlb_gen, next_tlb_gen); - write_cr3(build_cr3(next->pgd, new_asid)); + load_new_mm_cr3(next->pgd, new_asid, true); /* * NB: This gets called via leave_mm() in the idle path @@ -243,7 +261,7 @@ void switch_mm_irqs_off(struct mm_struct trace_tlb_flush_rcuidle(TLB_FLUSH_ON_TASK_SWITCH, TLB_FLUSH_ALL); } else { /* The new ASID is already up to date. */ - write_cr3(build_cr3_noflush(next->pgd, new_asid)); + load_new_mm_cr3(next->pgd, new_asid, false); /* See above wrt _rcuidle. */ trace_tlb_flush_rcuidle(TLB_FLUSH_ON_TASK_SWITCH, 0);