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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
c97db4a0 RM |
2 | /* |
3 | * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text. | |
4 | * Here we can supply some information useful to userland. | |
5 | */ | |
6 | ||
c97db4a0 | 7 | #include <linux/version.h> |
810bab44 | 8 | #include <linux/elfnote.h> |
c97db4a0 | 9 | |
810bab44 JF |
10 | /* Ideally this would use UTS_NAME, but using a quoted string here |
11 | doesn't work. Remember to change this when changing the | |
12 | kernel's name. */ | |
13 | ELFNOTE_START(Linux, 0, "a") | |
c97db4a0 | 14 | .long LINUX_VERSION_CODE |
810bab44 | 15 | ELFNOTE_END |
24037a8b JF |
16 | |
17 | #ifdef CONFIG_XEN | |
24037a8b JF |
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. | |
d2eea68e RM |
31 | * |
32 | * At runtime, the fake hardware feature will be considered to be present | |
33 | * if its bit is set in the mask word. So, we start with the mask 0, and | |
34 | * at boot time we set VDSO_NOTE_NONEGSEG_BIT if running under Xen. | |
24037a8b JF |
35 | */ |
36 | ||
0c2f51a7 | 37 | #include "../../xen/vdso.h" /* Defines VDSO_NOTE_NONEGSEG_BIT. */ |
24037a8b JF |
38 | |
39 | ELFNOTE_START(GNU, 2, "a") | |
d2eea68e | 40 | .long 1 /* ncaps */ |
6c3652ef | 41 | VDSO32_NOTE_MASK: /* Symbol used by arch/x86/xen/setup.c */ |
d2eea68e | 42 | .long 0 /* mask */ |
24037a8b JF |
43 | .byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */ |
44 | ELFNOTE_END | |
45 | #endif |