tree e310d0f9918d7a47359872fa519e2abe10b5d522 parent ecd02dddd1d5bfc2141cbd0e205a53fb9d849c9e author Roland McGrath <[EMAIL PROTECTED]> Sun, 17 Apr 2005 05:24:48 -0700 committer Linus Torvalds <[EMAIL PROTECTED]> Sun, 17 Apr 2005 05:24:48 -0700
[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 <[EMAIL PROTECTED]> Signed-off-by: Andrew Morton <[EMAIL PROTECTED]> Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]> i386/kernel/Makefile | 6 ++++-- i386/kernel/vsyscall-note.S | 25 +++++++++++++++++++++++++ i386/kernel/vsyscall.lds.S | 3 ++- 3 files changed, 31 insertions(+), 3 deletions(-) Index: arch/i386/kernel/Makefile =================================================================== --- 06660dbabc1df1a5c6ee23d48bb07e09e2960a88/arch/i386/kernel/Makefile (mode:100644 sha1:933787a46b4c481c68588d8072a692b6743ae093) +++ e310d0f9918d7a47359872fa519e2abe10b5d522/arch/i386/kernel/Makefile (mode:100644 sha1:aacdae6f372d4ba0440f3795d89ba27bc0b0f3c5) @@ -56,7 +56,8 @@ SYSCFLAGS_vsyscall-int80.so = $(vsyscall-flags) $(obj)/vsyscall-int80.so $(obj)/vsyscall-sysenter.so: \ -$(obj)/vsyscall-%.so: $(src)/vsyscall.lds $(obj)/vsyscall-%.o FORCE +$(obj)/vsyscall-%.so: $(src)/vsyscall.lds \ + $(obj)/vsyscall-%.o $(obj)/vsyscall-note.o FORCE $(call if_changed,syscall) # We also create a special relocatable object that should mirror the symbol @@ -67,5 +68,6 @@ $(obj)/built-in.o: ld_flags += -R $(obj)/vsyscall-syms.o SYSCFLAGS_vsyscall-syms.o = -r -$(obj)/vsyscall-syms.o: $(src)/vsyscall.lds $(obj)/vsyscall-sysenter.o FORCE +$(obj)/vsyscall-syms.o: $(src)/vsyscall.lds \ + $(obj)/vsyscall-sysenter.o $(obj)/vsyscall-note.o FORCE $(call if_changed,syscall) Index: arch/i386/kernel/vsyscall-note.S =================================================================== --- /dev/null (tree:06660dbabc1df1a5c6ee23d48bb07e09e2960a88) +++ e310d0f9918d7a47359872fa519e2abe10b5d522/arch/i386/kernel/vsyscall-note.S (mode:100664 sha1:d4b5be4f3d5fc67a157d38b24388c5c069dfe106) @@ -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 Index: arch/i386/kernel/vsyscall.lds.S =================================================================== --- 06660dbabc1df1a5c6ee23d48bb07e09e2960a88/arch/i386/kernel/vsyscall.lds.S (mode:100644 sha1:3a8329d6536e7e5fee04375c2e8209e0bdd09632) +++ e310d0f9918d7a47359872fa519e2abe10b5d522/arch/i386/kernel/vsyscall.lds.S (mode:100644 sha1:a7977707c8e5098455b56ed9c9463c124ad6e883) @@ -23,7 +23,7 @@ . = VSYSCALL_BASE + 0x400; .text : { *(.text) } :text =0x90909090 - + .note : { *(.note.*) } :text :note .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr .eh_frame : { KEEP (*(.eh_frame)) } :text .dynamic : { *(.dynamic) } :text :dynamic @@ -43,6 +43,7 @@ { text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ + note PT_NOTE FLAGS(4); /* PF_R */ eh_frame_hdr 0x6474e550; /* PT_GNU_EH_FRAME, but ld doesn't match the name */ } - To unsubscribe from this list: send the line "unsubscribe bk-commits-head" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html