blob: c83f257346966dc170f953bba1399f94ffc20742 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
/*
* This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
* Here we can supply some information useful to userland.
*/
#include <linux/version.h>
#include <linux/elfnote.h>
/* Ideally this would use UTS_NAME, but using a quoted string here
doesn't work. Remember to change this when changing the
kernel's name. */
ELFNOTE_START(Linux, 0, "a")
.long LINUX_VERSION_CODE
ELFNOTE_END
#ifdef CONFIG_XEN
/*
* Add a special note telling glibc's dynamic linker a fake hardware
* flavor that it will use to choose the search path for libraries in the
* same way it uses real hardware capabilities like "mmx".
* We supply "nosegneg" as the fake capability, to indicate that we
* do not like negative offsets in instructions using segment overrides,
* since we implement those inefficiently. This makes it possible to
* install libraries optimized to avoid those access patterns in someplace
* like /lib/i686/tls/nosegneg. Note that an /etc/ld.so.conf.d/file
* corresponding to the bits here is needed to make ldconfig work right.
* It should contain:
* hwcap 1 nosegneg
* to match the mapping of bit to name that we give here.
*
* At runtime, the fake hardware feature will be considered to be present
* if its bit is set in the mask word. So, we start with the mask 0, and
* at boot time we set VDSO_NOTE_NONEGSEG_BIT if running under Xen.
*/
#include "../../xen/vdso.h" /* Defines VDSO_NOTE_NONEGSEG_BIT. */
ELFNOTE_START(GNU, 2, "a")
.long 1 /* ncaps */
VDSO32_NOTE_MASK: /* Symbol used by arch/x86/xen/setup.c */
.long 0 /* mask */
.byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */
ELFNOTE_END
#endif
|