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-rw-r--r--arch/x86_64/ia32/syscall32.c83
1 files changed, 0 insertions, 83 deletions
diff --git a/arch/x86_64/ia32/syscall32.c b/arch/x86_64/ia32/syscall32.c
deleted file mode 100644
index 15013bac181c..000000000000
--- a/arch/x86_64/ia32/syscall32.c
+++ /dev/null
@@ -1,83 +0,0 @@
1/* Copyright 2002,2003 Andi Kleen, SuSE Labs */
2
3/* vsyscall handling for 32bit processes. Map a stub page into it
4 on demand because 32bit cannot reach the kernel's fixmaps */
5
6#include <linux/mm.h>
7#include <linux/string.h>
8#include <linux/kernel.h>
9#include <linux/gfp.h>
10#include <linux/init.h>
11#include <linux/stringify.h>
12#include <linux/security.h>
13#include <asm/proto.h>
14#include <asm/tlbflush.h>
15#include <asm/ia32_unistd.h>
16#include <asm/vsyscall32.h>
17
18extern unsigned char syscall32_syscall[], syscall32_syscall_end[];
19extern unsigned char syscall32_sysenter[], syscall32_sysenter_end[];
20extern int sysctl_vsyscall32;
21
22static struct page *syscall32_pages[1];
23static int use_sysenter = -1;
24
25struct linux_binprm;
26
27/* Setup a VMA at program startup for the vsyscall page */
28int syscall32_setup_pages(struct linux_binprm *bprm, int exstack)
29{
30 struct mm_struct *mm = current->mm;
31 int ret;
32
33 down_write(&mm->mmap_sem);
34 /*
35 * MAYWRITE to allow gdb to COW and set breakpoints
36 *
37 * Make sure the vDSO gets into every core dump.
38 * Dumping its contents makes post-mortem fully interpretable later
39 * without matching up the same kernel and hardware config to see
40 * what PC values meant.
41 */
42 /* Could randomize here */
43 ret = install_special_mapping(mm, VSYSCALL32_BASE, PAGE_SIZE,
44 VM_READ|VM_EXEC|
45 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
46 VM_ALWAYSDUMP,
47 syscall32_pages);
48 up_write(&mm->mmap_sem);
49 return ret;
50}
51
52static int __init init_syscall32(void)
53{
54 char *syscall32_page = (void *)get_zeroed_page(GFP_KERNEL);
55 if (!syscall32_page)
56 panic("Cannot allocate syscall32 page");
57 syscall32_pages[0] = virt_to_page(syscall32_page);
58 if (use_sysenter > 0) {
59 memcpy(syscall32_page, syscall32_sysenter,
60 syscall32_sysenter_end - syscall32_sysenter);
61 } else {
62 memcpy(syscall32_page, syscall32_syscall,
63 syscall32_syscall_end - syscall32_syscall);
64 }
65 return 0;
66}
67
68__initcall(init_syscall32);
69
70/* May not be __init: called during resume */
71void syscall32_cpu_init(void)
72{
73 if (use_sysenter < 0)
74 use_sysenter = (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL);
75
76 /* Load these always in case some future AMD CPU supports
77 SYSENTER from compat mode too. */
78 checking_wrmsrl(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
79 checking_wrmsrl(MSR_IA32_SYSENTER_ESP, 0ULL);
80 checking_wrmsrl(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target);
81
82 wrmsrl(MSR_CSTAR, ia32_cstar_target);
83}