[PATCH] i386 vDSO: add PT_NOTE segment
This patch adds an ELF note to the vDSO giving the LINUX_VERSION_CODE
value. Having this in the vDSO lets the dynamic linker avoid the `uname'
syscall it now always does at startup to ascertain the kernel ABI
available.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/i386/kernel/vsyscall-note.S b/arch/i386/kernel/vsyscall-note.S
new file mode 100644
index 0000000..d4b5be4
--- /dev/null
+++ b/arch/i386/kernel/vsyscall-note.S
@@ -0,0 +1,25 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+
+#define ASM_ELF_NOTE_BEGIN(name, flags, vendor, type) \
+ .section name, flags; \
+ .balign 4; \
+ .long 1f - 0f; /* name length */ \
+ .long 3f - 2f; /* data length */ \
+ .long type; /* note type */ \
+0: .asciz vendor; /* vendor name */ \
+1: .balign 4; \
+2:
+
+#define ASM_ELF_NOTE_END \
+3: .balign 4; /* pad out section */ \
+ .previous
+
+ ASM_ELF_NOTE_BEGIN(".note.kernel-version", "a", UTS_SYSNAME, 0)
+ .long LINUX_VERSION_CODE
+ ASM_ELF_NOTE_END
