From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f199.google.com (mail-qk0-f199.google.com [209.85.220.199]) by kanga.kvack.org (Postfix) with ESMTP id C5E496B000A for ; Sat, 14 Jul 2018 05:32:04 -0400 (EDT) Received: by mail-qk0-f199.google.com with SMTP id u68-v6so25052815qku.5 for ; Sat, 14 Jul 2018 02:32:04 -0700 (PDT) Received: from outgoing-stata.csail.mit.edu (outgoing-stata.csail.mit.edu. [128.30.2.210]) by mx.google.com with ESMTP id j2-v6si4663489qtp.300.2018.07.14.02.32.03 for ; Sat, 14 Jul 2018 02:32:03 -0700 (PDT) Subject: [PATCH 4.4.y 041/101] x86/mm: Factor out LDT init from context init From: "Srivatsa S. Bhat" Date: Sat, 14 Jul 2018 02:31:57 -0700 Message-ID: <153156071778.10043.13239124304280929230.stgit@srivatsa-ubuntu> In-Reply-To: <153156030832.10043.13438231886571087086.stgit@srivatsa-ubuntu> References: <153156030832.10043.13438231886571087086.stgit@srivatsa-ubuntu> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: gregkh@linuxfoundation.org, stable@vger.kernel.org Cc: Dave Hansen , Thomas Gleixner , Andrew Morton , Andy Lutomirski , Borislav Petkov , Brian Gerst , Dave Hansen , Denys Vlasenko , "H. Peter Anvin" , Linus Torvalds , Peter Zijlstra , Rik van Riel , linux-mm@kvack.org, Ingo Molnar , "Matt Helsley (VMware)" , Alexey Makhalov , Bo Gan matt.helsley@gmail.com, rostedt@goodmis.orgamakhalov@vmware.comganb@vmware.com, srivatsa@csail.mit.edu, srivatsab@vmware.com From: Dave Hansen commit 39a0526fb3f7d93433d146304278477eb463f8af upstream The arch-specific mm_context_t is a great place to put protection-key allocation state. But, we need to initialize the allocation state because pkey 0 is always "allocated". All of the runtime initialization of mm_context_t is done in *_ldt() manipulation functions. This renames the existing LDT functions like this: init_new_context() -> init_new_context_ldt() destroy_context() -> destroy_context_ldt() and makes init_new_context() and destroy_context() available for generic use. Signed-off-by: Dave Hansen Reviewed-by: Thomas Gleixner Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210234.DB34FCC5@viggo.jf.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Srivatsa S. Bhat Reviewed-by: Matt Helsley (VMware) Reviewed-by: Alexey Makhalov Reviewed-by: Bo Gan --- arch/x86/include/asm/mmu_context.h | 21 ++++++++++++++++----- arch/x86/kernel/ldt.c | 4 ++-- 2 files changed, 18 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 9bfc5fd..1c4794f 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -52,15 +52,15 @@ struct ldt_struct { /* * Used for LDT copy/destruction. */ -int init_new_context(struct task_struct *tsk, struct mm_struct *mm); -void destroy_context(struct mm_struct *mm); +int init_new_context_ldt(struct task_struct *tsk, struct mm_struct *mm); +void destroy_context_ldt(struct mm_struct *mm); #else /* CONFIG_MODIFY_LDT_SYSCALL */ -static inline int init_new_context(struct task_struct *tsk, - struct mm_struct *mm) +static inline int init_new_context_ldt(struct task_struct *tsk, + struct mm_struct *mm) { return 0; } -static inline void destroy_context(struct mm_struct *mm) {} +static inline void destroy_context_ldt(struct mm_struct *mm) {} #endif static inline void load_mm_ldt(struct mm_struct *mm) @@ -102,6 +102,17 @@ static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) this_cpu_write(cpu_tlbstate.state, TLBSTATE_LAZY); } +static inline int init_new_context(struct task_struct *tsk, + struct mm_struct *mm) +{ + init_new_context_ldt(tsk, mm); + return 0; +} +static inline void destroy_context(struct mm_struct *mm) +{ + destroy_context_ldt(mm); +} + extern void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk); diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c index bc42936..8bc68cf 100644 --- a/arch/x86/kernel/ldt.c +++ b/arch/x86/kernel/ldt.c @@ -119,7 +119,7 @@ static void free_ldt_struct(struct ldt_struct *ldt) * we do not have to muck with descriptors here, that is * done in switch_mm() as needed. */ -int init_new_context(struct task_struct *tsk, struct mm_struct *mm) +int init_new_context_ldt(struct task_struct *tsk, struct mm_struct *mm) { struct ldt_struct *new_ldt; struct mm_struct *old_mm; @@ -160,7 +160,7 @@ out_unlock: * * 64bit: Don't touch the LDT register - we're already in the next thread. */ -void destroy_context(struct mm_struct *mm) +void destroy_context_ldt(struct mm_struct *mm) { free_ldt_struct(mm->context.ldt); mm->context.ldt = NULL;