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@@ -80,7 +80,7 @@ __vsyscall_page:
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ret
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```
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-Let's go back to the implementation of the `map_vsyscall` function and return to the implementation of the `__vsyscall_page`, later. After we receiving the physical address of the `__vsyscall_page`, we check the value of the `vsyscall_mode` variable and set the [fix-mapped](http://0xax.gitbooks.io/linux-insides/content/mm/linux-mm-2.html) address for the `vsyscall` page with the `__set_fixmap` macro:
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+Let's go back to the implementation of the `map_vsyscall` function and return to the implementation of the `__vsyscall_page` later. After we received the physical address of the `__vsyscall_page`, we check the value of the `vsyscall_mode` variable and set the [fix-mapped](http://0xax.gitbooks.io/linux-insides/content/mm/linux-mm-2.html) address for the `vsyscall` page with the `__set_fixmap` macro:
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```C
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if (vsyscall_mode != NONE)
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@@ -266,7 +266,7 @@ static int __init init_vdso(void)
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#endif
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```
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-Both function initialize the `vdso_image` structure. This structure is defined in the two generated source code files: the [arch/x86/entry/vdso/vdso-image-64.c](https://github.com/torvalds/linux/blob/16f73eb02d7e1765ccab3d2018e0bd98eb93d973/arch/x86/entry/vdso/vdso-image-64.c) and the [arch/x86/entry/vdso/vdso-image-64.c](https://github.com/torvalds/linux/blob/16f73eb02d7e1765ccab3d2018e0bd98eb93d973/arch/x86/entry/vdso/vdso-image-64.c). These source code files generated by the [vdso2c](https://github.com/torvalds/linux/blob/16f73eb02d7e1765ccab3d2018e0bd98eb93d973/arch/x86/entry/vdso/vdso2c.c) program from the different source code files, represent different approaches to call a system call like `int 0x80`, `sysenter` and etc. The full set of the images depends on the kernel configuration.
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+Both functions initialize the `vdso_image` structure. This structure is defined in the two generated source code files: the [arch/x86/entry/vdso/vdso-image-64.c](https://github.com/torvalds/linux/blob/16f73eb02d7e1765ccab3d2018e0bd98eb93d973/arch/x86/entry/vdso/vdso-image-64.c) and the [arch/x86/entry/vdso/vdso-image-64.c](https://github.com/torvalds/linux/blob/16f73eb02d7e1765ccab3d2018e0bd98eb93d973/arch/x86/entry/vdso/vdso-image-64.c). These source code files generated by the [vdso2c](https://github.com/torvalds/linux/blob/16f73eb02d7e1765ccab3d2018e0bd98eb93d973/arch/x86/entry/vdso/vdso2c.c) program from the different source code files, represent different approaches to call a system call like `int 0x80`, `sysenter` and etc. The full set of the images depends on the kernel configuration.
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For example for the `x86_64` Linux kernel it will contain `vdso_image_64`:
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@@ -357,7 +357,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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}
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```
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-The `map_vdso` function is defined in the same source code file and maps pages for the `vDSO` and for the shared `vDSO` variables. That's all. The main differences between the `vsyscall` and the `vDSO` concepts is that `vsyscal` has a static address of `ffffffffff600000` and implements `3` system calls, whereas the `vDSO` loads dynamically and implements four system calls:
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+The `map_vdso` function is defined in the same source code file and maps pages for the `vDSO` and for the shared `vDSO` variables. That's all. The main differences between the `vsyscall` and the `vDSO` concepts is that `vsyscall` has a static address of `ffffffffff600000` and implements `3` system calls, whereas the `vDSO` loads dynamically and implements four system calls:
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* `__vdso_clock_gettime`;
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* `__vdso_getcpu`;
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0xAX