kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

x86 vDSO: ia32 vdso32-syscall build

Browse source 
This puts the syscall version of the 32-bit vDSO in arch/x86/vdso/vdso32/
for 64-bit IA32 support.  This is not used yet, but it paves the way for
consolidating the 32-bit vDSO source and build logic all in one place.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Roland McGrath 2008-01-30 13:30:43 +01:00 committed by Ingo Molnar
parent 36197c92a2
commit 00f8b1bc0e
3 changed files with 76 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
arch/x86/vdso/Makefile
View file

@ -71,6 +71,7 @@ $(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
#
obj-$(VDSO32-y) += vdso32-syms.lds
vdso32.so-$(CONFIG_X86_32) += int80
vdso32.so-$(CONFIG_COMPAT) += syscall
vdso32.so-$(VDSO32-y) += sysenter
CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)

9
arch/x86/vdso/vdso32/sigreturn.S
View file

@ -6,9 +6,12 @@
* routines are constant for all vsyscall implementations.
*/
#include <asm/unistd.h>
#include <asm/unistd_32.h>
#include <asm/asm-offsets.h>
#ifndef SYSCALL_ENTER_KERNEL
#define SYSCALL_ENTER_KERNEL int $0x80
#endif
/* XXX
Should these be named "_sigtramp" or something?
@ -22,7 +25,7 @@ __kernel_sigreturn:
.LSTART_sigreturn:
popl %eax /* XXX does this mean it needs unwind info? */
movl $__NR_sigreturn, %eax
int $0x80
SYSCALL_ENTER_KERNEL
.LEND_sigreturn:
.size __kernel_sigreturn,.-.LSTART_sigreturn
@ -32,7 +35,7 @@ __kernel_sigreturn:
__kernel_rt_sigreturn:
.LSTART_rt_sigreturn:
movl $__NR_rt_sigreturn, %eax
int $0x80
SYSCALL_ENTER_KERNEL
.LEND_rt_sigreturn:
.size __kernel_rt_sigreturn,.-.LSTART_rt_sigreturn
.balign 32

69
arch/x86/vdso/vdso32/syscall.S Normal file
View file

@ -0,0 +1,69 @@
/*
* Code for the vsyscall page. This version uses the syscall instruction.
*/
#include <asm/asm-offsets.h>
#include <asm/segment.h>
.text
.globl __kernel_vsyscall
.type __kernel_vsyscall,@function
__kernel_vsyscall:
.LSTART_vsyscall:
push %ebp
.Lpush_ebp:
movl %ecx, %ebp
syscall
movl $__USER32_DS, %ecx
movl %ecx, %ss
movl %ebp, %ecx
popl %ebp
.Lpop_ebp:
ret
.LEND_vsyscall:
.size __kernel_vsyscall,.-.LSTART_vsyscall
.section .eh_frame,"a",@progbits
.LSTARTFRAME:
.long .LENDCIE-.LSTARTCIE
.LSTARTCIE:
.long 0 /* CIE ID */
.byte 1 /* Version number */
.string "zR" /* NUL-terminated augmentation string */
.uleb128 1 /* Code alignment factor */
.sleb128 -4 /* Data alignment factor */
.byte 8 /* Return address register column */
.uleb128 1 /* Augmentation value length */
.byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */
.byte 0x0c /* DW_CFA_def_cfa */
.uleb128 4
.uleb128 4
.byte 0x88 /* DW_CFA_offset, column 0x8 */
.uleb128 1
.align 4
.LENDCIE:
.long .LENDFDE1-.LSTARTFDE1 /* Length FDE */
.LSTARTFDE1:
.long .LSTARTFDE1-.LSTARTFRAME /* CIE pointer */
.long .LSTART_vsyscall-. /* PC-relative start address */
.long .LEND_vsyscall-.LSTART_vsyscall
.uleb128 0 /* Augmentation length */
/* What follows are the instructions for the table generation.
We have to record all changes of the stack pointer. */
.byte 0x40 + .Lpush_ebp-.LSTART_vsyscall /* DW_CFA_advance_loc */
.byte 0x0e /* DW_CFA_def_cfa_offset */
.uleb128 8
.byte 0x85, 0x02 /* DW_CFA_offset %ebp -8 */
.byte 0x40 + .Lpop_ebp-.Lpush_ebp /* DW_CFA_advance_loc */
.byte 0xc5 /* DW_CFA_restore %ebp */
.byte 0x0e /* DW_CFA_def_cfa_offset */
.uleb128 4
.align 4
.LENDFDE1:
/*
* Get the common code for the sigreturn entry points.
*/
#define SYSCALL_ENTER_KERNEL syscall
#include "sigreturn.S"