1/* SPDX-License-Identifier: GPL-2.0 */ 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 7#include <linux/version.h> 8#include <linux/elfnote.h> 9 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. */ 13ELFNOTE_START(Linux, 0, "a") 14 .long LINUX_VERSION_CODE 15ELFNOTE_END 16 17#ifdef CONFIG_XEN 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 * 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. 35 */ 36 37#include "../../xen/vdso.h" /* Defines VDSO_NOTE_NONEGSEG_BIT. */ 38 39ELFNOTE_START(GNU, 2, "a") 40 .long 1 /* ncaps */ 41VDSO32_NOTE_MASK: /* Symbol used by arch/x86/xen/setup.c */ 42 .long 0 /* mask */ 43 .byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */ 44ELFNOTE_END 45#endif 46