4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Andy Lutomirski <l...@kernel.org> commit da51da189a24bb9b7e2d5a123be096e51a4695a5 upstream. 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); Also simplify a few get_cpu()/put_cpu() sequences to preempt_disable()/preempt_enable(). Signed-off-by: Andy Lutomirski <l...@kernel.org> Reviewed-by: Borislav Petkov <b...@suse.de> Cc: Borislav Petkov <bpet...@suse.de> Cc: Brian Gerst <brge...@gmail.com> Cc: Dave Hansen <dave.han...@intel.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/2655d8b42ed940aa384fe18ee1129bbbcf730a08.1509609304.git.l...@kernel.org Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- 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 | 2 +- arch/x86/kernel/process_64.c | 2 +- arch/x86/kernel/vm86_32.c | 14 ++++++-------- arch/x86/xen/enlighten_pv.c | 7 +++---- 8 files changed, 20 insertions(+), 25 deletions(-) --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -16,10 +16,9 @@ #include <linux/cpumask.h> #include <asm/frame.h> -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. */ --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -134,7 +134,7 @@ 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); --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -518,9 +518,9 @@ static inline void native_set_iopl_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) @@ -545,10 +545,9 @@ static inline unsigned long current_top_ #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 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1570,7 +1570,7 @@ void cpu_init(void) initialize_tlbstate_and_flush(); 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); @@ -1625,7 +1625,7 @@ void cpu_init(void) initialize_tlbstate_and_flush(); 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); --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -287,7 +287,7 @@ __switch_to(struct task_struct *prev_p, * current_thread_info(). Refresh the SYSENTER configuration in * case prev or next is vm86. */ - load_sp0(tss, next); + load_sp0(next->sp0); refresh_sysenter_cs(next); this_cpu_write(cpu_current_top_of_stack, (unsigned long)task_stack_page(next_p) + --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -465,7 +465,7 @@ __switch_to(struct task_struct *prev_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 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -95,7 +95,6 @@ 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; @@ -147,13 +146,13 @@ void save_v86_state(struct kernel_vm86_r do_exit(SIGSEGV); } - tss = &per_cpu(cpu_tss, get_cpu()); + preempt_disable(); tsk->thread.sp0 = vm86->saved_sp0; tsk->thread.sysenter_cs = __KERNEL_CS; - load_sp0(tss, &tsk->thread); + load_sp0(tsk->thread.sp0); refresh_sysenter_cs(&tsk->thread); vm86->saved_sp0 = 0; - put_cpu(); + preempt_enable(); memcpy(®s->pt, &vm86->regs32, sizeof(struct pt_regs)); @@ -239,7 +238,6 @@ SYSCALL_DEFINE2(vm86, unsigned long, cmd 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; @@ -367,8 +365,8 @@ static long do_sys_vm86(struct vm86plus_ 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 */ + preempt_disable(); tsk->thread.sp0 += 16; if (static_cpu_has(X86_FEATURE_SEP)) { @@ -376,8 +374,8 @@ static long do_sys_vm86(struct vm86plus_ refresh_sysenter_cs(&tsk->thread); } - load_sp0(tss, &tsk->thread); - put_cpu(); + load_sp0(tsk->thread.sp0); + preempt_enable(); if (vm86->flags & VM86_SCREEN_BITMAP) mark_screen_rdonly(tsk->mm); --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -811,15 +811,14 @@ static void __init xen_write_gdt_entry_b } } -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)
