Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753793AbdIFVj1 (ORCPT ); Wed, 6 Sep 2017 17:39:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:50430 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753540AbdIFVhM (ORCPT ); Wed, 6 Sep 2017 17:37:12 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 100B021EAC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org From: Andy Lutomirski To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov , Brian Gerst , Andrew Cooper , Juergen Gross , Boris Ostrovsky , Kees Cook , Andy Lutomirski Subject: [RFC 10/17] x86/asm/64: Pass sp0 directly to load_sp0() Date: Wed, 6 Sep 2017 14:36:55 -0700 Message-Id: <66c53e714940bc07fa0165bdac6572796eb5c4a9.1504733277.git.luto@kernel.org> X-Mailer: git-send-email 2.13.5 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7588 Lines: 228 load_sp0() had an odd signature: void load_sp0(struct tss_struct *tss, struct thread_struct *thread); Simplify it to: void load_sp0(unsigned long sp0); Signed-off-by: Andy Lutomirski --- arch/x86/include/asm/paravirt.h | 5 ++--- arch/x86/include/asm/paravirt_types.h | 2 +- arch/x86/include/asm/processor.h | 9 ++++----- arch/x86/kernel/cpu/common.c | 4 ++-- arch/x86/kernel/process_32.c | 4 ++-- arch/x86/kernel/process_64.c | 2 +- arch/x86/kernel/vm86_32.c | 12 ++++-------- arch/x86/lguest/boot.c | 7 +++---- arch/x86/xen/enlighten_pv.c | 7 +++---- 9 files changed, 22 insertions(+), 30 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 9ccac1926587..209dada6207e 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -15,10 +15,9 @@ #include #include -static inline void load_sp0(struct tss_struct *tss, - struct thread_struct *thread) +static inline void load_sp0(unsigned long sp0) { - PVOP_VCALL2(pv_cpu_ops.load_sp0, tss, thread); + PVOP_VCALL1(pv_cpu_ops.load_sp0, sp0); } /* The paravirtualized CPUID instruction. */ diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 9ffc36bfe4cd..04a091615c08 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -136,7 +136,7 @@ struct pv_cpu_ops { void (*alloc_ldt)(struct desc_struct *ldt, unsigned entries); void (*free_ldt)(struct desc_struct *ldt, unsigned entries); - void (*load_sp0)(struct tss_struct *tss, struct thread_struct *t); + void (*load_sp0)(unsigned long sp0); void (*set_iopl_mask)(unsigned mask); diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index ee37fb86900a..85ddfc1a9bb5 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -510,9 +510,9 @@ static inline void native_set_iopl_mask(unsigned mask) } static inline void -native_load_sp0(struct tss_struct *tss, struct thread_struct *thread) +native_load_sp0(unsigned long sp0) { - tss->x86_tss.sp0 = thread->sp0; + this_cpu_write(cpu_tss.x86_tss.sp0, sp0); } static inline void native_swapgs(void) @@ -537,10 +537,9 @@ static inline unsigned long current_top_of_stack(void) #else #define __cpuid native_cpuid -static inline void load_sp0(struct tss_struct *tss, - struct thread_struct *thread) +static inline void load_sp0(unsigned long sp0) { - native_load_sp0(tss, thread); + native_load_sp0(sp0); } #define set_iopl_mask native_set_iopl_mask diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index c8b39870f33e..40312b3ef9de 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1554,7 +1554,7 @@ void cpu_init(void) BUG_ON(me->mm); enter_lazy_tlb(&init_mm, me); - load_sp0(t, ¤t->thread); + load_sp0(current->thread.sp0); set_tss_desc(cpu, t); load_TR_desc(); load_mm_ldt(&init_mm); @@ -1608,7 +1608,7 @@ void cpu_init(void) BUG_ON(curr->mm); enter_lazy_tlb(&init_mm, curr); - load_sp0(t, thread); + load_sp0(thread->sp0); set_tss_desc(cpu, t); load_TR_desc(); load_mm_ldt(&init_mm); diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 9f217b5ef438..e06a98e3a772 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -286,8 +286,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) * Reload esp0 and cpu_current_top_of_stack. This changes * current_thread_info(). */ - load_sp0(tss, next); - refresh_sysenter_cs(); /* in case prev or next is vm86 */ + load_sp0(next->sp0); + refresh_sysenter_cs(next); /* in case prev or next is vm86 */ this_cpu_write(cpu_current_top_of_stack, (unsigned long)task_stack_page(next_p) + THREAD_SIZE); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 985e7569ab57..06c4393b19b3 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -437,7 +437,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) this_cpu_write(current_task, next_p); /* Reload sp0. */ - load_sp0(tss, next); + load_sp0(next->sp0); /* * Now maybe reload the debug registers and handle I/O bitmaps diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index 9edda73dcc90..3b98b7771f15 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -94,7 +94,6 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) { - struct tss_struct *tss; struct task_struct *tsk = current; struct vm86plus_struct __user *user; struct vm86 *vm86 = current->thread.vm86; @@ -146,11 +145,10 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) do_exit(SIGSEGV); } - tss = &per_cpu(cpu_tss, get_cpu()); tsk->thread.sp0 = vm86->saved_sp0; tsk->thread.sysenter_cs = __KERNEL_CS; - load_sp0(tss, &tsk->thread); - refresh_sysenter_cs(); + load_sp0(tsk->thread.sp0); + refresh_sysenter_cs(&tsk->thread); vm86->saved_sp0 = 0; put_cpu(); @@ -238,7 +236,6 @@ SYSCALL_DEFINE2(vm86, unsigned long, cmd, unsigned long, arg) static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) { - struct tss_struct *tss; struct task_struct *tsk = current; struct vm86 *vm86 = tsk->thread.vm86; struct kernel_vm86_regs vm86regs; @@ -366,16 +363,15 @@ static long do_sys_vm86(struct vm86plus_struct __user *user_vm86, bool plus) vm86->saved_sp0 = tsk->thread.sp0; lazy_save_gs(vm86->regs32.gs); - tss = &per_cpu(cpu_tss, get_cpu()); /* make room for real-mode segments */ tsk->thread.sp0 += 16; if (static_cpu_has(X86_FEATURE_SEP)) { tsk->thread.sysenter_cs = 0; - refresh_sysenter_cs(); + refresh_sysenter_cs(&tsk->thread); } - load_sp0(tss, &tsk->thread); + load_sp0(tsk->thread.sp0); put_cpu(); if (vm86->flags & VM86_SCREEN_BITMAP) diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 99472698c931..07bb8e9a69ac 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -1054,12 +1054,11 @@ static void lguest_time_init(void) * will not tolerate us trying to use that), the stack pointer, and the number * of pages in the stack. */ -static void lguest_load_sp0(struct tss_struct *tss, - struct thread_struct *thread) +static void lguest_load_sp0(unsigned long sp0) { - lazy_hcall3(LHCALL_SET_STACK, __KERNEL_DS | 0x1, thread->sp0, + lazy_hcall3(LHCALL_SET_STACK, __KERNEL_DS | 0x1, sp0, THREAD_SIZE / PAGE_SIZE); - tss->x86_tss.sp0 = thread->sp0; + this_cpu_write(cpu_tss.x86_tss.sp0, sp0); } /* Let's just say, I wouldn't do debugging under a Guest. */ diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 811e4ddb3f37..6c803c3ee831 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -771,15 +771,14 @@ static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry, } } -static void xen_load_sp0(struct tss_struct *tss, - struct thread_struct *thread) +static void xen_load_sp0(unsigned long sp0) { struct multicall_space mcs; mcs = xen_mc_entry(0); - MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0); + MULTI_stack_switch(mcs.mc, __KERNEL_DS, sp0); xen_mc_issue(PARAVIRT_LAZY_CPU); - tss->x86_tss.sp0 = thread->sp0; + this_cpu_write(cpu_tss.x86_tss.sp0, sp0); } void xen_set_iopl_mask(unsigned mask) -- 2.13.5