Commit | Line | Data |
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c97db4a0 RM |
1 | /* |
2 | * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text. | |
3 | * Here we can supply some information useful to userland. | |
4 | */ | |
5 | ||
c97db4a0 | 6 | #include <linux/version.h> |
810bab44 | 7 | #include <linux/elfnote.h> |
c97db4a0 | 8 | |
810bab44 JF |
9 | /* Ideally this would use UTS_NAME, but using a quoted string here |
10 | doesn't work. Remember to change this when changing the | |
11 | kernel's name. */ | |
12 | ELFNOTE_START(Linux, 0, "a") | |
c97db4a0 | 13 | .long LINUX_VERSION_CODE |
810bab44 | 14 | ELFNOTE_END |
24037a8b JF |
15 | |
16 | #ifdef CONFIG_XEN | |
17 | ||
18 | /* | |
19 | * Add a special note telling glibc's dynamic linker a fake hardware | |
20 | * flavor that it will use to choose the search path for libraries in the | |
21 | * same way it uses real hardware capabilities like "mmx". | |
22 | * We supply "nosegneg" as the fake capability, to indicate that we | |
23 | * do not like negative offsets in instructions using segment overrides, | |
24 | * since we implement those inefficiently. This makes it possible to | |
25 | * install libraries optimized to avoid those access patterns in someplace | |
26 | * like /lib/i686/tls/nosegneg. Note that an /etc/ld.so.conf.d/file | |
27 | * corresponding to the bits here is needed to make ldconfig work right. | |
28 | * It should contain: | |
29 | * hwcap 1 nosegneg | |
30 | * to match the mapping of bit to name that we give here. | |
31 | */ | |
32 | ||
33 | /* Bit used for the pseudo-hwcap for non-negative segments. We use | |
34 | bit 1 to avoid bugs in some versions of glibc when bit 0 is | |
35 | used; the choice is otherwise arbitrary. */ | |
36 | #define VDSO_NOTE_NONEGSEG_BIT 1 | |
37 | ||
38 | ELFNOTE_START(GNU, 2, "a") | |
39 | .long 1, 1<<VDSO_NOTE_NONEGSEG_BIT /* ncaps, mask */ | |
40 | .byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */ | |
41 | ELFNOTE_END | |
42 | #endif |