mirror of
https://github.com/torvalds/linux.git
synced 2024-11-13 15:41:39 +00:00
ccbeed3a05
Impact: pt_regs changed, lazy gs handling made optional, add slight
overhead to SAVE_ALL, simplifies error_code path a bit
On x86_32, %gs hasn't been used by kernel and handled lazily. pt_regs
doesn't have place for it and gs is saved/loaded only when necessary.
In preparation for stack protector support, this patch makes lazy %gs
handling optional by doing the followings.
* Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs.
* Save and restore %gs along with other registers in entry_32.S unless
LAZY_GS. Note that this unfortunately adds "pushl $0" on SAVE_ALL
even when LAZY_GS. However, it adds no overhead to common exit path
and simplifies entry path with error code.
* Define different user_gs accessors depending on LAZY_GS and add
lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS. The
lazy_*_gs() ops are used to save, load and clear %gs lazily.
* Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly.
xen and lguest changes need to be verified.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
348 lines
9.7 KiB
C
348 lines
9.7 KiB
C
#ifndef _ASM_X86_ELF_H
|
|
#define _ASM_X86_ELF_H
|
|
|
|
/*
|
|
* ELF register definitions..
|
|
*/
|
|
|
|
#include <asm/ptrace.h>
|
|
#include <asm/user.h>
|
|
#include <asm/auxvec.h>
|
|
|
|
typedef unsigned long elf_greg_t;
|
|
|
|
#define ELF_NGREG (sizeof(struct user_regs_struct) / sizeof(elf_greg_t))
|
|
typedef elf_greg_t elf_gregset_t[ELF_NGREG];
|
|
|
|
typedef struct user_i387_struct elf_fpregset_t;
|
|
|
|
#ifdef __i386__
|
|
|
|
typedef struct user_fxsr_struct elf_fpxregset_t;
|
|
|
|
#define R_386_NONE 0
|
|
#define R_386_32 1
|
|
#define R_386_PC32 2
|
|
#define R_386_GOT32 3
|
|
#define R_386_PLT32 4
|
|
#define R_386_COPY 5
|
|
#define R_386_GLOB_DAT 6
|
|
#define R_386_JMP_SLOT 7
|
|
#define R_386_RELATIVE 8
|
|
#define R_386_GOTOFF 9
|
|
#define R_386_GOTPC 10
|
|
#define R_386_NUM 11
|
|
|
|
/*
|
|
* These are used to set parameters in the core dumps.
|
|
*/
|
|
#define ELF_CLASS ELFCLASS32
|
|
#define ELF_DATA ELFDATA2LSB
|
|
#define ELF_ARCH EM_386
|
|
|
|
#else
|
|
|
|
/* x86-64 relocation types */
|
|
#define R_X86_64_NONE 0 /* No reloc */
|
|
#define R_X86_64_64 1 /* Direct 64 bit */
|
|
#define R_X86_64_PC32 2 /* PC relative 32 bit signed */
|
|
#define R_X86_64_GOT32 3 /* 32 bit GOT entry */
|
|
#define R_X86_64_PLT32 4 /* 32 bit PLT address */
|
|
#define R_X86_64_COPY 5 /* Copy symbol at runtime */
|
|
#define R_X86_64_GLOB_DAT 6 /* Create GOT entry */
|
|
#define R_X86_64_JUMP_SLOT 7 /* Create PLT entry */
|
|
#define R_X86_64_RELATIVE 8 /* Adjust by program base */
|
|
#define R_X86_64_GOTPCREL 9 /* 32 bit signed pc relative
|
|
offset to GOT */
|
|
#define R_X86_64_32 10 /* Direct 32 bit zero extended */
|
|
#define R_X86_64_32S 11 /* Direct 32 bit sign extended */
|
|
#define R_X86_64_16 12 /* Direct 16 bit zero extended */
|
|
#define R_X86_64_PC16 13 /* 16 bit sign extended pc relative */
|
|
#define R_X86_64_8 14 /* Direct 8 bit sign extended */
|
|
#define R_X86_64_PC8 15 /* 8 bit sign extended pc relative */
|
|
|
|
#define R_X86_64_NUM 16
|
|
|
|
/*
|
|
* These are used to set parameters in the core dumps.
|
|
*/
|
|
#define ELF_CLASS ELFCLASS64
|
|
#define ELF_DATA ELFDATA2LSB
|
|
#define ELF_ARCH EM_X86_64
|
|
|
|
#endif
|
|
|
|
#include <asm/vdso.h>
|
|
|
|
extern unsigned int vdso_enabled;
|
|
|
|
/*
|
|
* This is used to ensure we don't load something for the wrong architecture.
|
|
*/
|
|
#define elf_check_arch_ia32(x) \
|
|
(((x)->e_machine == EM_386) || ((x)->e_machine == EM_486))
|
|
|
|
#include <asm/processor.h>
|
|
#include <asm/system.h>
|
|
|
|
#ifdef CONFIG_X86_32
|
|
#include <asm/desc.h>
|
|
|
|
#define elf_check_arch(x) elf_check_arch_ia32(x)
|
|
|
|
/* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program starts %edx
|
|
contains a pointer to a function which might be registered using `atexit'.
|
|
This provides a mean for the dynamic linker to call DT_FINI functions for
|
|
shared libraries that have been loaded before the code runs.
|
|
|
|
A value of 0 tells we have no such handler.
|
|
|
|
We might as well make sure everything else is cleared too (except for %esp),
|
|
just to make things more deterministic.
|
|
*/
|
|
#define ELF_PLAT_INIT(_r, load_addr) \
|
|
do { \
|
|
_r->bx = 0; _r->cx = 0; _r->dx = 0; \
|
|
_r->si = 0; _r->di = 0; _r->bp = 0; \
|
|
_r->ax = 0; \
|
|
} while (0)
|
|
|
|
/*
|
|
* regs is struct pt_regs, pr_reg is elf_gregset_t (which is
|
|
* now struct_user_regs, they are different)
|
|
*/
|
|
|
|
#define ELF_CORE_COPY_REGS_COMMON(pr_reg, regs) \
|
|
do { \
|
|
pr_reg[0] = regs->bx; \
|
|
pr_reg[1] = regs->cx; \
|
|
pr_reg[2] = regs->dx; \
|
|
pr_reg[3] = regs->si; \
|
|
pr_reg[4] = regs->di; \
|
|
pr_reg[5] = regs->bp; \
|
|
pr_reg[6] = regs->ax; \
|
|
pr_reg[7] = regs->ds & 0xffff; \
|
|
pr_reg[8] = regs->es & 0xffff; \
|
|
pr_reg[9] = regs->fs & 0xffff; \
|
|
pr_reg[11] = regs->orig_ax; \
|
|
pr_reg[12] = regs->ip; \
|
|
pr_reg[13] = regs->cs & 0xffff; \
|
|
pr_reg[14] = regs->flags; \
|
|
pr_reg[15] = regs->sp; \
|
|
pr_reg[16] = regs->ss & 0xffff; \
|
|
} while (0);
|
|
|
|
#define ELF_CORE_COPY_REGS(pr_reg, regs) \
|
|
do { \
|
|
ELF_CORE_COPY_REGS_COMMON(pr_reg, regs);\
|
|
pr_reg[10] = get_user_gs(regs); \
|
|
} while (0);
|
|
|
|
#define ELF_CORE_COPY_KERNEL_REGS(pr_reg, regs) \
|
|
do { \
|
|
ELF_CORE_COPY_REGS_COMMON(pr_reg, regs);\
|
|
savesegment(gs, pr_reg[10]); \
|
|
} while (0);
|
|
|
|
#define ELF_PLATFORM (utsname()->machine)
|
|
#define set_personality_64bit() do { } while (0)
|
|
|
|
#else /* CONFIG_X86_32 */
|
|
|
|
/*
|
|
* This is used to ensure we don't load something for the wrong architecture.
|
|
*/
|
|
#define elf_check_arch(x) \
|
|
((x)->e_machine == EM_X86_64)
|
|
|
|
#define compat_elf_check_arch(x) elf_check_arch_ia32(x)
|
|
|
|
static inline void start_ia32_thread(struct pt_regs *regs, u32 ip, u32 sp)
|
|
{
|
|
loadsegment(fs, 0);
|
|
loadsegment(ds, __USER32_DS);
|
|
loadsegment(es, __USER32_DS);
|
|
load_gs_index(0);
|
|
regs->ip = ip;
|
|
regs->sp = sp;
|
|
regs->flags = X86_EFLAGS_IF;
|
|
regs->cs = __USER32_CS;
|
|
regs->ss = __USER32_DS;
|
|
}
|
|
|
|
static inline void elf_common_init(struct thread_struct *t,
|
|
struct pt_regs *regs, const u16 ds)
|
|
{
|
|
regs->ax = regs->bx = regs->cx = regs->dx = 0;
|
|
regs->si = regs->di = regs->bp = 0;
|
|
regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0;
|
|
regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
|
|
t->fs = t->gs = 0;
|
|
t->fsindex = t->gsindex = 0;
|
|
t->ds = t->es = ds;
|
|
}
|
|
|
|
#define ELF_PLAT_INIT(_r, load_addr) \
|
|
do { \
|
|
elf_common_init(¤t->thread, _r, 0); \
|
|
clear_thread_flag(TIF_IA32); \
|
|
} while (0)
|
|
|
|
#define COMPAT_ELF_PLAT_INIT(regs, load_addr) \
|
|
elf_common_init(¤t->thread, regs, __USER_DS)
|
|
|
|
#define compat_start_thread(regs, ip, sp) \
|
|
do { \
|
|
start_ia32_thread(regs, ip, sp); \
|
|
set_fs(USER_DS); \
|
|
} while (0)
|
|
|
|
#define COMPAT_SET_PERSONALITY(ex) \
|
|
do { \
|
|
if (test_thread_flag(TIF_IA32)) \
|
|
clear_thread_flag(TIF_ABI_PENDING); \
|
|
else \
|
|
set_thread_flag(TIF_ABI_PENDING); \
|
|
current->personality |= force_personality32; \
|
|
} while (0)
|
|
|
|
#define COMPAT_ELF_PLATFORM ("i686")
|
|
|
|
/*
|
|
* regs is struct pt_regs, pr_reg is elf_gregset_t (which is
|
|
* now struct_user_regs, they are different). Assumes current is the process
|
|
* getting dumped.
|
|
*/
|
|
|
|
#define ELF_CORE_COPY_REGS(pr_reg, regs) \
|
|
do { \
|
|
unsigned v; \
|
|
(pr_reg)[0] = (regs)->r15; \
|
|
(pr_reg)[1] = (regs)->r14; \
|
|
(pr_reg)[2] = (regs)->r13; \
|
|
(pr_reg)[3] = (regs)->r12; \
|
|
(pr_reg)[4] = (regs)->bp; \
|
|
(pr_reg)[5] = (regs)->bx; \
|
|
(pr_reg)[6] = (regs)->r11; \
|
|
(pr_reg)[7] = (regs)->r10; \
|
|
(pr_reg)[8] = (regs)->r9; \
|
|
(pr_reg)[9] = (regs)->r8; \
|
|
(pr_reg)[10] = (regs)->ax; \
|
|
(pr_reg)[11] = (regs)->cx; \
|
|
(pr_reg)[12] = (regs)->dx; \
|
|
(pr_reg)[13] = (regs)->si; \
|
|
(pr_reg)[14] = (regs)->di; \
|
|
(pr_reg)[15] = (regs)->orig_ax; \
|
|
(pr_reg)[16] = (regs)->ip; \
|
|
(pr_reg)[17] = (regs)->cs; \
|
|
(pr_reg)[18] = (regs)->flags; \
|
|
(pr_reg)[19] = (regs)->sp; \
|
|
(pr_reg)[20] = (regs)->ss; \
|
|
(pr_reg)[21] = current->thread.fs; \
|
|
(pr_reg)[22] = current->thread.gs; \
|
|
asm("movl %%ds,%0" : "=r" (v)); (pr_reg)[23] = v; \
|
|
asm("movl %%es,%0" : "=r" (v)); (pr_reg)[24] = v; \
|
|
asm("movl %%fs,%0" : "=r" (v)); (pr_reg)[25] = v; \
|
|
asm("movl %%gs,%0" : "=r" (v)); (pr_reg)[26] = v; \
|
|
} while (0);
|
|
|
|
/* I'm not sure if we can use '-' here */
|
|
#define ELF_PLATFORM ("x86_64")
|
|
extern void set_personality_64bit(void);
|
|
extern unsigned int sysctl_vsyscall32;
|
|
extern int force_personality32;
|
|
|
|
#endif /* !CONFIG_X86_32 */
|
|
|
|
#define CORE_DUMP_USE_REGSET
|
|
#define USE_ELF_CORE_DUMP
|
|
#define ELF_EXEC_PAGESIZE 4096
|
|
|
|
/* This is the location that an ET_DYN program is loaded if exec'ed. Typical
|
|
use of this is to invoke "./ld.so someprog" to test out a new version of
|
|
the loader. We need to make sure that it is out of the way of the program
|
|
that it will "exec", and that there is sufficient room for the brk. */
|
|
|
|
#define ELF_ET_DYN_BASE (TASK_SIZE / 3 * 2)
|
|
|
|
/* This yields a mask that user programs can use to figure out what
|
|
instruction set this CPU supports. This could be done in user space,
|
|
but it's not easy, and we've already done it here. */
|
|
|
|
#define ELF_HWCAP (boot_cpu_data.x86_capability[0])
|
|
|
|
/* This yields a string that ld.so will use to load implementation
|
|
specific libraries for optimization. This is more specific in
|
|
intent than poking at uname or /proc/cpuinfo.
|
|
|
|
For the moment, we have only optimizations for the Intel generations,
|
|
but that could change... */
|
|
|
|
#define SET_PERSONALITY(ex) set_personality_64bit()
|
|
|
|
/*
|
|
* An executable for which elf_read_implies_exec() returns TRUE will
|
|
* have the READ_IMPLIES_EXEC personality flag set automatically.
|
|
*/
|
|
#define elf_read_implies_exec(ex, executable_stack) \
|
|
(executable_stack != EXSTACK_DISABLE_X)
|
|
|
|
struct task_struct;
|
|
|
|
#define ARCH_DLINFO_IA32(vdso_enabled) \
|
|
do { \
|
|
if (vdso_enabled) { \
|
|
NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \
|
|
NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \
|
|
} \
|
|
} while (0)
|
|
|
|
#ifdef CONFIG_X86_32
|
|
|
|
#define VDSO_HIGH_BASE (__fix_to_virt(FIX_VDSO))
|
|
|
|
#define ARCH_DLINFO ARCH_DLINFO_IA32(vdso_enabled)
|
|
|
|
/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
|
|
|
|
#else /* CONFIG_X86_32 */
|
|
|
|
#define VDSO_HIGH_BASE 0xffffe000U /* CONFIG_COMPAT_VDSO address */
|
|
|
|
/* 1GB for 64bit, 8MB for 32bit */
|
|
#define STACK_RND_MASK (test_thread_flag(TIF_IA32) ? 0x7ff : 0x3fffff)
|
|
|
|
#define ARCH_DLINFO \
|
|
do { \
|
|
if (vdso_enabled) \
|
|
NEW_AUX_ENT(AT_SYSINFO_EHDR, \
|
|
(unsigned long)current->mm->context.vdso); \
|
|
} while (0)
|
|
|
|
#define AT_SYSINFO 32
|
|
|
|
#define COMPAT_ARCH_DLINFO ARCH_DLINFO_IA32(sysctl_vsyscall32)
|
|
|
|
#define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)
|
|
|
|
#endif /* !CONFIG_X86_32 */
|
|
|
|
#define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
|
|
|
|
#define VDSO_ENTRY \
|
|
((unsigned long)VDSO32_SYMBOL(VDSO_CURRENT_BASE, vsyscall))
|
|
|
|
struct linux_binprm;
|
|
|
|
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
|
|
extern int arch_setup_additional_pages(struct linux_binprm *bprm,
|
|
int uses_interp);
|
|
|
|
extern int syscall32_setup_pages(struct linux_binprm *, int exstack);
|
|
#define compat_arch_setup_additional_pages syscall32_setup_pages
|
|
|
|
extern unsigned long arch_randomize_brk(struct mm_struct *mm);
|
|
#define arch_randomize_brk arch_randomize_brk
|
|
|
|
#endif /* _ASM_X86_ELF_H */
|