提交 6c3652ef 编写于 作者: R Roland McGrath 提交者: Ingo Molnar

x86 vDSO: i386 vdso32

This makes the i386 kernel use the new vDSO build in arch/x86/vdso/vdso32/
to replace the old one from arch/x86/kernel/.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
上级 0249c9c1
......@@ -110,7 +110,8 @@ libs-y += arch/x86/lib/
core-y += arch/x86/kernel/ \
arch/x86/mm/ \
$(mcore-y)/ \
arch/x86/crypto/
arch/x86/crypto/ \
arch/x86/vdso/
drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
drivers-$(CONFIG_PCI) += arch/x86/pci/
# must be linked after kernel/
......
......@@ -33,7 +33,7 @@ obj-$(CONFIG_X86_NUMAQ) += numaq_32.o
obj-$(CONFIG_X86_SUMMIT_NUMA) += summit_32.o
obj-$(CONFIG_KPROBES) += kprobes_32.o
obj-$(CONFIG_MODULES) += module_32.o
obj-y += sysenter_32.o vsyscall_32.o
obj-y += sysenter_32.o
obj-$(CONFIG_ACPI_SRAT) += srat_32.o
obj-$(CONFIG_EFI) += efi_32.o efi_stub_32.o
obj-$(CONFIG_DOUBLEFAULT) += doublefault_32.o
......@@ -48,44 +48,3 @@ obj-$(CONFIG_PARAVIRT) += paravirt_32.o
obj-y += pcspeaker.o
obj-$(CONFIG_SCx200) += scx200_32.o
# vsyscall_32.o contains the vsyscall DSO images as __initdata.
# We must build both images before we can assemble it.
# Note: kbuild does not track this dependency due to usage of .incbin
$(obj)/vsyscall_32.o: $(obj)/vsyscall-int80_32.so $(obj)/vsyscall-sysenter_32.so
targets += $(foreach F,int80 sysenter,vsyscall-$F_32.o vsyscall-$F_32.so)
targets += vsyscall-note_32.o vsyscall_32.lds
$(obj)/vsyscall-%_32.o: $(src)/../vdso/vdso32/%.S
$(call if_changed_dep,as_o_S)
# The DSO images are built using a special linker script.
quiet_cmd_syscall = SYSCALL $@
cmd_syscall = $(CC) -m elf_i386 -nostdlib $(SYSCFLAGS_$(@F)) \
-Wl,-T,$(filter-out FORCE,$^) -o $@
export CPPFLAGS_vsyscall_32.lds += -P -C -Ui386
vsyscall-flags = -shared -s -Wl,-soname=linux-gate.so.1 \
$(call ld-option, -Wl$(comma)--hash-style=sysv)
SYSCFLAGS_vsyscall-sysenter_32.so = $(vsyscall-flags)
SYSCFLAGS_vsyscall-int80_32.so = $(vsyscall-flags)
$(obj)/vsyscall-int80_32.so $(obj)/vsyscall-sysenter_32.so: \
$(obj)/vsyscall-%.so: $(src)/vsyscall_32.lds \
$(obj)/vsyscall-%.o $(obj)/vsyscall-note_32.o FORCE
$(call if_changed,syscall)
# We also create a special relocatable object that should mirror the symbol
# table and layout of the linked DSO. With ld -R we can then refer to
# these symbols in the kernel code rather than hand-coded addresses.
extra-y += vsyscall-syms.o
$(obj)/built-in.o: $(obj)/vsyscall-syms.o
$(obj)/built-in.o: ld_flags += -R $(obj)/vsyscall-syms.o
SYSCFLAGS_vsyscall-syms.o = -r
$(obj)/vsyscall-syms.o: $(src)/vsyscall_32.lds \
$(obj)/vsyscall-sysenter_32.o $(obj)/vsyscall-note_32.o FORCE
$(call if_changed,syscall)
......@@ -111,8 +111,6 @@ void foo(void)
DEFINE(PTRS_PER_PMD, PTRS_PER_PMD);
DEFINE(PTRS_PER_PGD, PTRS_PER_PGD);
DEFINE(VDSO_PRELINK_asm, VDSO_PRELINK);
OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx);
#ifdef CONFIG_PARAVIRT
......
......@@ -23,6 +23,7 @@
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/i387.h>
#include <asm/vdso.h>
#include "sigframe_32.h"
#define DEBUG_SIG 0
......@@ -362,7 +363,7 @@ static int setup_frame(int sig, struct k_sigaction *ka,
}
if (current->binfmt->hasvdso)
restorer = (void *)VDSO_SYM(&__kernel_sigreturn);
restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn);
else
restorer = (void *)&frame->retcode;
if (ka->sa.sa_flags & SA_RESTORER)
......@@ -459,7 +460,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
goto give_sigsegv;
/* Set up to return from userspace. */
restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn);
restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
if (ka->sa.sa_flags & SA_RESTORER)
restorer = ka->sa.sa_restorer;
err |= __put_user(restorer, &frame->pretcode);
......
......@@ -23,6 +23,7 @@
#include <asm/unistd.h>
#include <asm/elf.h>
#include <asm/tlbflush.h>
#include <asm/vdso.h>
enum {
VDSO_DISABLED = 0,
......@@ -259,9 +260,6 @@ int __init sysenter_setup(void)
return 0;
}
/* Defined in vsyscall-sysenter.S */
extern void SYSENTER_RETURN;
/* Setup a VMA at program startup for the vsyscall page */
int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
{
......@@ -308,7 +306,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
current->mm->context.vdso = (void *)addr;
current_thread_info()->sysenter_return =
(void *)VDSO_SYM(&SYSENTER_RETURN);
VDSO32_SYMBOL(addr, SYSENTER_RETURN);
up_fail:
up_write(&mm->mmap_sem);
......
/*
* Linker script for vsyscall DSO. The vsyscall page is an ELF shared
* object prelinked to its virtual address, and with only one read-only
* segment (that fits in one page). This script controls its layout.
*/
#include <asm/asm-offsets.h>
SECTIONS
{
. = VDSO_PRELINK_asm + SIZEOF_HEADERS;
.hash : { *(.hash) } :text
.gnu.hash : { *(.gnu.hash) }
.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. */
. = VDSO_PRELINK_asm + 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
.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 */
note PT_NOTE 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);
......@@ -14,7 +14,8 @@ vdso-install-$(VDSO32-y) += $(vdso32-y:=.so)
vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vvar.o
# files to link into kernel
obj-y := vma.o vdso.o
obj-$(VDSO64-y) += vma.o vdso.o
obj-$(CONFIG_X86_32) += vdso32.o
vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
......@@ -52,7 +53,7 @@ $(obj)/vclock_gettime.o: KBUILD_CFLAGS = $(CFL)
$(obj)/vgetcpu.o: KBUILD_CFLAGS = $(CFL)
targets += vdso-syms.lds
obj-y += vdso-syms.lds
obj-$(VDSO64-y) += vdso-syms.lds
#
# Match symbols in the DSO that look like VDSO*; produce a file of constants.
......@@ -68,6 +69,7 @@ $(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
#
# Build multiple 32-bit vDSO images to choose from at boot time.
#
obj-$(VDSO32-y) += vdso32-syms.lds
vdso32.so-$(CONFIG_X86_32) += int80
vdso32.so-$(VDSO32-y) += sysenter
......@@ -84,6 +86,8 @@ targets += vdso32/note.o $(vdso32.so-y:%=vdso32/%.o)
extra-y += $(vdso32.so-y:%=vdso32-%.so)
$(obj)/vdso32.o: $(vdso32.so-y:%=$(obj)/vdso32-%.so)
KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS))
$(vdso32.so-y:%=$(obj)/vdso32-%.so.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
$(vdso32.so-y:%=$(obj)/vdso32-%.so.dbg): asflags-$(CONFIG_X86_64) += -m32
......
......@@ -4,12 +4,12 @@ __INITDATA
.globl vsyscall_int80_start, vsyscall_int80_end
vsyscall_int80_start:
.incbin "arch/x86/kernel/vsyscall-int80_32.so"
.incbin "arch/x86/vdso/vdso32-int80.so"
vsyscall_int80_end:
.globl vsyscall_sysenter_start, vsyscall_sysenter_end
vsyscall_sysenter_start:
.incbin "arch/x86/kernel/vsyscall-sysenter_32.so"
.incbin "arch/x86/vdso/vdso32-sysenter.so"
vsyscall_sysenter_end:
__FINIT
......@@ -35,10 +35,9 @@ ELFNOTE_END
#include "../../xen/vdso.h" /* Defines VDSO_NOTE_NONEGSEG_BIT. */
.globl VDSO_NOTE_MASK
ELFNOTE_START(GNU, 2, "a")
.long 1 /* ncaps */
VDSO_NOTE_MASK:
VDSO32_NOTE_MASK: /* Symbol used by arch/x86/xen/setup.c */
.long 0 /* mask */
.byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */
ELFNOTE_END
......
......@@ -45,8 +45,7 @@ __kernel_vsyscall:
/* 14: System call restart point is here! (SYSENTER_RETURN-2) */
jmp .Lenter_kernel
/* 16: System call normal return point is here! */
.globl SYSENTER_RETURN /* Symbol used by sysenter.c */
SYSENTER_RETURN:
VDSO32_SYSENTER_RETURN: /* Symbol used by sysenter.c via vdso32-syms.h */
pop %ebp
.Lpop_ebp:
pop %edx
......
......@@ -10,6 +10,7 @@
#include <linux/pm.h>
#include <asm/elf.h>
#include <asm/vdso.h>
#include <asm/e820.h>
#include <asm/setup.h>
#include <asm/xen/hypervisor.h>
......@@ -61,10 +62,8 @@ static void xen_idle(void)
*/
static void fiddle_vdso(void)
{
extern u32 VDSO_NOTE_MASK; /* See ../kernel/vsyscall-note.S. */
extern char vsyscall_int80_start;
u32 *mask = (u32 *) ((unsigned long) &VDSO_NOTE_MASK - VDSO_PRELINK +
&vsyscall_int80_start);
u32 *mask = VDSO32_SYMBOL(&vsyscall_int80_start, NOTE_MASK);
*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
}
......
......@@ -78,6 +78,7 @@ typedef struct user_fxsr_struct elf_fpxregset_t;
#include <asm/processor.h>
#include <asm/system.h> /* for savesegment */
#include <asm/desc.h>
#include <asm/vdso.h>
/*
* This is used to ensure we don't load something for the wrong architecture.
......@@ -247,17 +248,9 @@ extern int dump_task_extended_fpu (struct task_struct *,
#define VDSO_HIGH_BASE (__fix_to_virt(FIX_VDSO))
#define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
#define VDSO_PRELINK 0
#define VDSO_SYM(x) \
(VDSO_CURRENT_BASE + (unsigned long)(x) - VDSO_PRELINK)
#define VDSO_HIGH_EHDR ((const struct elfhdr *) VDSO_HIGH_BASE)
#define VDSO_EHDR ((const struct elfhdr *) VDSO_CURRENT_BASE)
extern void __kernel_vsyscall;
#define VDSO_ENTRY VDSO_SYM(&__kernel_vsyscall)
#define VDSO_ENTRY \
((unsigned long) VDSO32_SYMBOL(VDSO_CURRENT_BASE, vsyscall))
/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
......
#ifndef _ASM_X86_VDSO_H
#define _ASM_X86_VDSO_H 1
#ifdef CONFIG_X86_64
extern const char VDSO64_PRELINK[];
/*
......@@ -10,5 +11,18 @@ extern const char VDSO64_PRELINK[];
#define VDSO64_SYMBOL(base, name) ({ \
extern const char VDSO64_##name[]; \
(void *) (VDSO64_##name - VDSO64_PRELINK + (unsigned long) (base)); })
#endif
#if defined CONFIG_X86_32 || defined CONFIG_COMPAT
extern const char VDSO32_PRELINK[];
/*
* Given a pointer to the vDSO image, find the pointer to VDSO32_name
* as that symbol is defined in the vDSO sources or linker script.
*/
#define VDSO32_SYMBOL(base, name) ({ \
extern const char VDSO32_##name[]; \
(void *) (VDSO32_##name - VDSO32_PRELINK + (unsigned long) (base)); })
#endif
#endif /* asm-x86/vdso.h */
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