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Diffstat (limited to 'arch/x86_64/ia32/vsyscall.lds')
-rw-r--r--arch/x86_64/ia32/vsyscall.lds77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/x86_64/ia32/vsyscall.lds b/arch/x86_64/ia32/vsyscall.lds
new file mode 100644
index 000000000000..fa4b4dd4a9ff
--- /dev/null
+++ b/arch/x86_64/ia32/vsyscall.lds
@@ -0,0 +1,77 @@
+/*
+ * Linker script for vsyscall DSO. The vsyscall page is an ELF shared
+ * object prelinked to its virtual address. This script controls its layout.
+ */
+
+/* This must match <asm/fixmap.h>. */
+VSYSCALL_BASE = 0xffffe000;
+
+SECTIONS
+{
+ . = VSYSCALL_BASE + SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ /* This linker script is used both with -r and with -shared.
+ For the layouts to match, we need to skip more than enough
+ space for the dynamic symbol table et al. If this amount
+ is insufficient, ld -shared will barf. Just increase it here. */
+ . = VSYSCALL_BASE + 0x400;
+
+ .text.vsyscall : { *(.text.vsyscall) } :text =0x90909090
+
+ /* This is an 32bit object and we cannot easily get the offsets
+ into the 64bit kernel. Just hardcode them here. This assumes
+ that all the stubs don't need more than 0x100 bytes. */
+ . = VSYSCALL_BASE + 0x500;
+
+ .text.sigreturn : { *(.text.sigreturn) } :text =0x90909090
+
+ . = VSYSCALL_BASE + 0x600;
+
+ .text.rtsigreturn : { *(.text.rtsigreturn) } :text =0x90909090
+
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
+ .eh_frame : { KEEP (*(.eh_frame)) } :text
+ .dynamic : { *(.dynamic) } :text :dynamic
+ .useless : {
+ *(.got.plt) *(.got)
+ *(.data .data.* .gnu.linkonce.d.*)
+ *(.dynbss)
+ *(.bss .bss.* .gnu.linkonce.b.*)
+ } :text
+}
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ eh_frame_hdr 0x6474e550; /* PT_GNU_EH_FRAME, but ld doesn't match the name */
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ LINUX_2.5 {
+ global:
+ __kernel_vsyscall;
+ __kernel_sigreturn;
+ __kernel_rt_sigreturn;
+
+ local: *;
+ };
+}
+
+/* The ELF entry point can be used to set the AT_SYSINFO value. */
+ENTRY(__kernel_vsyscall);