diff options
| -rw-r--r-- | arch/x86/Kconfig | 18 | ||||
| -rw-r--r-- | arch/x86/include/asm/fixmap.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/page_64.h | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/processor.h | 8 | ||||
| -rw-r--r-- | arch/x86/include/asm/vgtod.h | 19 | ||||
| -rw-r--r-- | arch/x86/include/asm/vsyscall.h | 33 | ||||
| -rw-r--r-- | arch/x86/include/asm/vvar.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/Makefile | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 10 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/time.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/vsyscall_64.c | 147 | ||||
| -rw-r--r-- | arch/x86/mm/init_64.c | 49 | ||||
| -rw-r--r-- | arch/x86/vdso/vgetcpu.c | 2 | ||||
| -rw-r--r-- | arch/x86/vdso/vma.c | 83 | ||||
| -rw-r--r-- | arch/x86/xen/mmu.c | 6 |
16 files changed, 190 insertions, 200 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 666ac6651c17..bea3a0159496 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -992,6 +992,24 @@ config X86_ESPFIX64 def_bool y depends on X86_16BIT && X86_64 +config X86_VSYSCALL_EMULATION + bool "Enable vsyscall emulation" if EXPERT + default y + depends on X86_64 + ---help--- + This enables emulation of the legacy vsyscall page. Disabling + it is roughly equivalent to booting with vsyscall=none, except + that it will also disable the helpful warning if a program + tries to use a vsyscall. With this option set to N, offending + programs will just segfault, citing addresses of the form + 0xffffffffff600?00. + + This option is required by many programs built before 2013, and + care should be used even with newer programs if set to N. + + Disabling this option saves about 7K of kernel size and + possibly 4K of additional runtime pagetable memory. + config TOSHIBA tristate "Toshiba Laptop support" depends on X86_32 diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h index bf728e49c53c..f80d70009ff8 100644 --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -69,7 +69,9 @@ enum fixed_addresses { #ifdef CONFIG_X86_32 FIX_HOLE, #else +#ifdef CONFIG_X86_VSYSCALL_EMULATION VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT, +#endif #ifdef CONFIG_PARAVIRT_CLOCK PVCLOCK_FIXMAP_BEGIN, PVCLOCK_FIXMAP_END = PVCLOCK_FIXMAP_BEGIN+PVCLOCK_VSYSCALL_NR_PAGES-1, diff --git a/arch/x86/include/asm/page_64.h b/arch/x86/include/asm/page_64.h index f408caf73430..b3bebf9e5746 100644 --- a/arch/x86/include/asm/page_64.h +++ b/arch/x86/include/asm/page_64.h @@ -39,6 +39,8 @@ void copy_page(void *to, void *from); #endif /* !__ASSEMBLY__ */ -#define __HAVE_ARCH_GATE_AREA 1 +#ifdef CONFIG_X86_VSYSCALL_EMULATION +# define __HAVE_ARCH_GATE_AREA 1 +#endif #endif /* _ASM_X86_PAGE_64_H */ diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 25b8de0f21c0..a092a0cce0b7 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -894,7 +894,13 @@ extern unsigned long thread_saved_pc(struct task_struct *tsk); #else /* - * User space process size. 47bits minus one guard page. + * User space process size. 47bits minus one guard page. The guard + * page is necessary on Intel CPUs: if a SYSCALL instruction is at + * the highest possible canonical userspace address, then that + * syscall will enter the kernel with a non-canonical return + * address, and SYSRET will explode dangerously. We avoid this + * particular problem by preventing anything from being mapped + * at the maximum canonical address. */ #define TASK_SIZE_MAX ((1UL << 47) - PAGE_SIZE) diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h index 3c3366c2e37f..e7e9682a33e9 100644 --- a/arch/x86/include/asm/vgtod.h +++ b/arch/x86/include/asm/vgtod.h @@ -70,4 +70,23 @@ static inline void gtod_write_end(struct vsyscall_gtod_data *s) ++s->seq; } +#ifdef CONFIG_X86_64 + +#define VGETCPU_CPU_MASK 0xfff + +static inline unsigned int __getcpu(void) +{ + unsigned int p; + + /* + * Load per CPU data from GDT. LSL is faster than RDTSCP and + * works on all CPUs. + */ + asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG)); + + return p; +} + +#endif /* CONFIG_X86_64 */ + #endif /* _ASM_X86_VGTOD_H */ diff --git a/arch/x86/include/asm/vsyscall.h b/arch/x86/include/asm/vsyscall.h index 2a46ca720afc..6ba66ee79710 100644 --- a/arch/x86/include/asm/vsyscall.h +++ b/arch/x86/include/asm/vsyscall.h @@ -4,15 +4,7 @@ #include <linux/seqlock.h> #include <uapi/asm/vsyscall.h> -#define VGETCPU_RDTSCP 1 -#define VGETCPU_LSL 2 - -/* kernel space (writeable) */ -extern int vgetcpu_mode; -extern struct timezone sys_tz; - -#include <asm/vvar.h> - +#ifdef CONFIG_X86_VSYSCALL_EMULATION extern void map_vsyscall(void); /* @@ -20,25 +12,12 @@ extern void map_vsyscall(void); * Returns true if handled. */ extern bool emulate_vsyscall(struct pt_regs *regs, unsigned long address); - -#ifdef CONFIG_X86_64 - -#define VGETCPU_CPU_MASK 0xfff - -static inline unsigned int __getcpu(void) +#else +static inline void map_vsyscall(void) {} +static inline bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) { - unsigned int p; - - if (VVAR(vgetcpu_mode) == VGETCPU_RDTSCP) { - /* Load per CPU data from RDTSCP */ - native_read_tscp(&p); - } else { - /* Load per CPU data from GDT */ - asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG)); - } - - return p; + return false; } -#endif /* CONFIG_X86_64 */ +#endif #endif /* _ASM_X86_VSYSCALL_H */ diff --git a/arch/x86/include/asm/vvar.h b/arch/x86/include/asm/vvar.h index 5d2b9ad2c6d2..3f32dfc2ab73 100644 --- a/arch/x86/include/asm/vvar.h +++ b/arch/x86/include/asm/vvar.h @@ -44,8 +44,6 @@ extern char __vvar_page; /* DECLARE_VVAR(offset, type, name) */ -DECLARE_VVAR(0, volatile unsigned long, jiffies) -DECLARE_VVAR(16, int, vgetcpu_mode) DECLARE_VVAR(128, struct vsyscall_gtod_data, vsyscall_gtod_data) #undef DECLARE_VVAR diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 8f1e77440b2b..5d4502c8b983 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -28,8 +28,7 @@ obj-$(CONFIG_X86_32) += i386_ksyms_32.o obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o obj-$(CONFIG_X86_64) += mcount_64.o obj-y += syscall_$(BITS).o vsyscall_gtod.o -obj-$(CONFIG_X86_64) += vsyscall_64.o -obj-$(CONFIG_X86_64) += vsyscall_emu_64.o +obj-$(CONFIG_X86_VSYSCALL_EMULATION) += vsyscall_64.o vsyscall_emu_64.o obj-$(CONFIG_X86_ESPFIX64) += espfix_64.o obj-$(CONFIG_SYSFS) += ksysfs.o obj-y += bootflag.o e820.o diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index cfa9b5b2c27a..c6049650c093 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -958,14 +958,6 @@ static void identify_cpu(struct cpuinfo_x86 *c) } #ifdef CONFIG_X86_64 -static void vgetcpu_set_mode(void) -{ - if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP)) - vgetcpu_mode = VGETCPU_RDTSCP; - else - vgetcpu_mode = VGETCPU_LSL; -} - #ifdef CONFIG_IA32_EMULATION /* May not be __init: called during resume */ static void syscall32_cpu_init(void) @@ -1008,8 +1000,6 @@ void __init identify_boot_cpu(void) #ifdef CONFIG_X86_32 sysenter_setup(); enable_sep_cpu(); -#else - vgetcpu_set_mode(); #endif cpu_detect_tlb(&boot_cpu_data); } diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 214245d6b996..ab4734e5411d 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1192,9 +1192,7 @@ void __init setup_arch(char **cmdline_p) tboot_probe(); -#ifdef CONFIG_X86_64 map_vsyscall(); -#endif generic_apic_probe(); diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c index 0fa29609b2c4..25adc0e16eaa 100644 --- a/arch/x86/kernel/time.c +++ b/arch/x86/kernel/time.c @@ -23,7 +23,7 @@ #include <asm/time.h> #ifdef CONFIG_X86_64 -__visible DEFINE_VVAR(volatile unsigned long, jiffies) = INITIAL_JIFFIES; +__visible volatile unsigned long jiffies __cacheline_aligned = INITIAL_JIFFIES; #endif unsigned long profile_pc(struct pt_regs *regs) diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 957779f4eb40..2dcc6ff6fdcc 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -1,59 +1,43 @@ /* + * Copyright (c) 2012-2014 Andy Lutomirski <luto@amacapital.net> + * + * Based on the original implementation which is: * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE * Copyright 2003 Andi Kleen, SuSE Labs. * - * [ NOTE: this mechanism is now deprecated in favor of the vDSO. ] + * Parts of the original code have been moved to arch/x86/vdso/vma.c + * + * This file implements vsyscall emulation. vsyscalls are a legacy ABI: + * Userspace can request certain kernel services by calling fixed + * addresses. This concept is problematic: * - * Thanks to hpa@transmeta.com for some useful hint. - * Special thanks to Ingo Molnar for his early experience with - * a different vsyscall implementation for Linux/IA32 and for the name. + * - It interferes with ASLR. + * - It's awkward to write code that lives in kernel addresses but is + * callable by userspace at fixed addresses. + * - The whole concept is impossible for 32-bit compat userspace. + * - UML cannot easily virtualize a vsyscall. * - * vsyscall 1 is located at -10Mbyte, vsyscall 2 is located - * at virtual address -10Mbyte+1024bytes etc... There are at max 4 - * vsyscalls. One vsyscall can reserve more than 1 slot to avoid - * jumping out of line if necessary. We cannot add more with this - * mechanism because older kernels won't return -ENOSYS. + * As of mid-2014, I believe that there is no new userspace code that + * will use a vsyscall if the vDSO is present. I hope that there will + * soon be no new userspace code that will ever use a vsyscall. * - * Note: the concept clashes with user mode linux. UML users should - * use the vDSO. + * The code in this file emulates vsyscalls when notified of a page + * fault to a vsyscall address. */ -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include <linux/time.h> -#include <linux/init.h> #include <linux/kernel.h> #include <linux/timer.h> -#include <linux/seqlock.h> -#include <linux/jiffies.h> -#include <linux/sysctl.h> -#include <linux/topology.h> -#include <linux/timekeeper_internal.h> -#include <linux/getcpu.h> -#include <linux/cpu.h> -#include <linux/smp.h> -#include <linux/notifier.h> #include <linux/syscalls.h> #include <linux/ratelimit.h> #include <asm/vsyscall.h> -#include <asm/pgtable.h> -#include <asm/compat.h> -#include <asm/page.h> #include <asm/unistd.h> #include <asm/fixmap.h> -#include <asm/errno.h> -#include <asm/io.h> -#include <asm/segment.h> -#include <asm/desc.h> -#include <asm/topology.h> #include <asm/traps.h> #define CREATE_TRACE_POINTS #include "vsyscall_trace.h" -DEFINE_VVAR(int, vgetcpu_mode); - static enum { EMULATE, NATIVE, NONE } vsyscall_mode = EMULATE; static int __init vsyscall_setup(char *str) @@ -222,6 +206,7 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) "seccomp tried to change syscall nr or ip"); do_exit(SIGSYS); } + regs->orig_ax = -1; if (tmp) goto do_ret; /* skip requested */ @@ -284,46 +269,54 @@ sigsegv: } /* - * Assume __initcall executes before all user space. Hopefully kmod - * doesn't violate that. We'll find out if it does. + * A pseudo VMA to allow ptrace access for the vsyscall page. This only + * covers the 64bit vsyscall page now. 32bit has a real VMA now and does + * not need special handling anymore: */ -static void vsyscall_set_cpu(int cpu) +static const char *gate_vma_name(struct vm_area_struct *vma) { - unsigned long d; - unsigned long node = 0; -#ifdef CONFIG_NUMA - node = cpu_to_node(cpu); -#endif - if (cpu_has(&cpu_data(cpu), X86_FEATURE_RDTSCP)) - write_rdtscp_aux((node << 12) | cpu); - - /* - * Store cpu number in limit so that it can be loaded quickly - * in user space in vgetcpu. (12 bits for the CPU and 8 bits for the node) - */ - d = 0x0f40000000000ULL; - d |= cpu; - d |= (node & 0xf) << 12; - d |= (node >> 4) << 48; - - write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S); + return "[vsyscall]"; } - -static void cpu_vsyscall_init(void *arg) +static struct vm_operations_struct gate_vma_ops = { + .name = gate_vma_name, +}; +static struct vm_area_struct gate_vma = { + .vm_start = VSYSCALL_ADDR, + .vm_end = VSYSCALL_ADDR + PAGE_SIZE, + .vm_page_prot = PAGE_READONLY_EXEC, + .vm_flags = VM_READ | VM_EXEC, + .vm_ops = &gate_vma_ops, +}; + +struct vm_area_struct *get_gate_vma(struct mm_struct *mm) { - /* preemption should be already off */ - vsyscall_set_cpu(raw_smp_processor_id()); +#ifdef CONFIG_IA32_EMULATION + if (!mm || mm->context.ia32_compat) + return NULL; +#endif + if (vsyscall_mode == NONE) + return NULL; + return &gate_vma; } -static int -cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg) +int in_gate_area(struct mm_struct *mm, unsigned long addr) { - long cpu = (long)arg; + struct vm_area_struct *vma = get_gate_vma(mm); + + if (!vma) + return 0; - if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) - smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 1); + return (addr >= vma->vm_start) && (addr < vma->vm_end); +} - return NOTIFY_DONE; +/* + * Use this when you have no reliable mm, typically from interrupt + * context. It is less reliable than using a task's mm and may give + * false positives. + */ +int in_gate_area_no_mm(unsigned long addr) +{ + return vsyscall_mode != NONE && (addr & PAGE_MASK) == VSYSCALL_ADDR; } void __init map_vsyscall(void) @@ -331,24 +324,12 @@ void __init map_vsyscall(void) extern char __vsyscall_page; unsigned long physaddr_vsyscall = __pa_symbol(&__vsyscall_page); - __set_fixmap(VSYSCALL_PAGE, physaddr_vsyscall, - vsyscall_mode == NATIVE - ? PAGE_KERNEL_VSYSCALL - : PAGE_KERNEL_VVAR); + if (vsyscall_mode != NONE) + __set_fixmap(VSYSCALL_PAGE, physaddr_vsyscall, + vsyscall_mode == NATIVE + ? PAGE_KERNEL_VSYSCALL + : PAGE_KERNEL_VVAR); + BUILD_BUG_ON((unsigned long)__fix_to_virt(VSYSCALL_PAGE) != (unsigned long)VSYSCALL_ADDR); } - -static int __init vsyscall_init(void) -{ - cpu_notifier_register_begin(); - - on_each_cpu(cpu_vsyscall_init, NULL, 1); - /* notifier priority > KVM */ - __hotcpu_notifier(cpu_vsyscall_notifier, 30); - - cpu_notifier_register_done(); - - return 0; -} -__initcall(vsyscall_init); diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 78e53c80fc12..30eb05ae7061 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1204,55 +1204,6 @@ int kern_addr_valid(unsigned long addr) return pfn_valid(pte_pfn(*pte)); } -/* - * A pseudo VMA to allow ptrace access for the vsyscall page. This only - * covers the 64bit vsyscall page now. 32bit has a real VMA now and does - * not need special handling anymore: - */ -static const char *gate_vma_name(struct vm_area_struct *vma) -{ - return "[vsyscall]"; -} -static struct vm_operations_struct gate_vma_ops = { - .name = gate_vma_name, -}; -static struct vm_area_struct gate_vma = { - .vm_start = VSYSCALL_ADDR, - .vm_end = VSYSCALL_ADDR + PAGE_SIZE, - .vm_page_prot = PAGE_READONLY_EXEC, - .vm_flags = VM_READ | VM_EXEC, - .vm_ops = &gate_vma_ops, -}; - -struct vm_area_struct *get_gate_vma(struct mm_struct *mm) -{ -#ifdef CONFIG_IA32_EMULATION - if (!mm || mm->context.ia32_compat) - return NULL; -#endif - return &gate_vma; -} - -int in_gate_area(struct mm_struct *mm, unsigned long addr) -{ - struct vm_area_struct *vma = get_gate_vma(mm); - - if (!vma) - return 0; - - return (addr >= vma->vm_start) && (addr < vma->vm_end); -} - -/* - * Use this when you have no reliable mm, typically from interrupt - * context. It is less reliable than using a task's mm and may give - * false positives. - */ -int in_gate_area_no_mm(unsigned long addr) -{ - return (addr & PAGE_MASK) == VSYSCALL_ADDR; -} - static unsigned long probe_memory_block_size(void) { /* start from 2g */ diff --git a/arch/x86/vdso/vgetcpu.c b/arch/x86/vdso/vgetcpu.c index 2f94b039e55b..8ec3d1f4ce9a 100644 --- a/arch/x86/vdso/vgetcpu.c +++ b/arch/x86/vdso/vgetcpu.c @@ -7,9 +7,7 @@ #include <linux/kernel.h> #include <linux/getcpu.h> -#include <linux/jiffies.h> #include <linux/time.h> -#include <asm/vsyscall.h> #include <asm/vgtod.h> notrace long diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c index 970463b566cf..009495b9ab4b 100644 --- a/arch/x86/vdso/vma.c +++ b/arch/x86/vdso/vma.c @@ -1,7 +1,8 @@ /* - * Set up the VMAs to tell the VM about the vDSO. * Copyright 2007 Andi Kleen, SUSE Labs. * Subject to the GPL, v.2 + * + * This contains most of the x86 vDSO kernel-side code. */ #include <linux/mm.h> #include <linux/err.h> @@ -10,17 +11,17 @@ #include <linux/init.h> #include <linux/random.h> #include <linux/elf.h> -#include <asm/vsyscall.h> +#include <linux/cpu.h> #include <asm/vgtod.h> #include <asm/proto.h> #include <asm/vdso.h> +#include <asm/vvar.h> #include <asm/page.h> #include <asm/hpet.h> +#include <asm/desc.h> #if defined(CONFIG_X86_64) unsigned int __read_mostly vdso64_enabled = 1; - -extern unsigned short vdso_sync_cpuid; #endif void __init init_vdso_image(const struct vdso_image *image) @@ -38,20 +39,6 @@ void __init init_vdso_image(const struct vdso_image *image) image->alt_len)); } -#if defined(CONFIG_X86_64) -static int __init init_vdso(void) -{ - init_vdso_image(&vdso_image_64); - -#ifdef CONFIG_X86_X32_ABI - init_vdso_image(&vdso_image_x32); -#endif - - return 0; -} -subsys_initcall(init_vdso); -#endif - struct linux_binprm; /* Put the vdso above the (randomized) stack with another randomized offset. @@ -238,3 +225,63 @@ static __init int vdso_setup(char *s) } __setup("vdso=", vdso_setup); #endif + +#ifdef CONFIG_X86_64 +static void vgetcpu_cpu_init(void *arg) +{ + int cpu = smp_processor_id(); + struct desc_struct d = { }; + unsigned long node = 0; +#ifdef CONFIG_NUMA + node = cpu_to_node(cpu); +#endif + if (cpu_has(&cpu_data(cpu), X86_FEATURE_RDTSCP)) + write_rdtscp_aux((node << 12) | cpu); + + /* + * Store cpu number in limit so that it can be loaded + * quickly in user space in vgetcpu. (12 bits for the CPU + * and 8 bits for the node) + */ + d.limit0 = cpu | ((node & 0xf) << 12); + d.limit = node >> 4; + d.type = 5; /* RO data, expand down, accessed */ + d.dpl = 3; /* Visible to user code */ + d.s = 1; /* Not a system segment */ + d.p = 1; /* Present */ + d.d = 1; /* 32-bit */ + + write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S); +} + +static int +vgetcpu_cpu_notifier(struct notifier_block *n, unsigned long action, void *arg) +{ + long cpu = (long)arg; + + if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) + smp_call_function_single(cpu, vgetcpu_cpu_init, NULL, 1); + + return NOTIFY_DONE; +} + +static int __init init_vdso(void) +{ + init_vdso_image(&vdso_image_64); + +#ifdef CONFIG_X86_X32_ABI + init_vdso_image(&vdso_image_x32); +#endif + + cpu_notifier_register_begin(); + + on_each_cpu(vgetcpu_cpu_init, NULL, 1); + /* notifier priority > KVM */ + __hotcpu_notifier(vgetcpu_cpu_notifier, 30); + + cpu_notifier_register_done(); + + return 0; +} +subsys_initcall(init_vdso); +#endif /* CONFIG_X86_64 */ diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 9855eb8ee4b3..8c8298d78185 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1412,8 +1412,10 @@ static int xen_pgd_alloc(struct mm_struct *mm) page->private = (unsigned long)user_pgd; if (user_pgd != NULL) { +#ifdef CONFIG_X86_VSYSCALL_EMULATION user_pgd[pgd_index(VSYSCALL_ADDR)] = __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE); +#endif ret = 0; } @@ -1976,7 +1978,7 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) # ifdef CONFIG_HIGHMEM case FIX_KMAP_BEGIN ... FIX_KMAP_END: # endif -#else +#elif defined(CONFIG_X86_VSYSCALL_EMULATION) case VSYSCALL_PAGE: #endif case FIX_TEXT_POKE0: @@ -2015,7 +2017,7 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) __native_set_fixmap(idx, pte); -#ifdef CONFIG_X86_64 +#ifdef CONFIG_X86_VSYSCALL_EMULATION /* Replicate changes to map the vsyscall page into the user pagetable vsyscall mapping. */ if (idx == VSYSCALL_PAGE) { |