/* * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text. * Here we can supply some information useful to userland. */ #include #include /* 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 "../../x86/xen/vdso.h" /* Defines VDSO_NOTE_NONEGSEG_BIT. */ .globl VDSO_NOTE_MASK ELFNOTE_START(GNU, 2, "a") .long 1 /* ncaps */ VDSO_NOTE_MASK: .long 0 /* mask */ .byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */ ELFNOTE_END #endif