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[PATCH] i386: Convert i386 PDA code to use %fs 

Convert the PDA code to use %fs rather than %gs as the segment for
per-processor data.  This is because some processors show a small but
measurable performance gain for reloading a NULL segment selector (as %fs
generally is in user-space) versus a non-NULL one (as %gs generally is).

On modern processors the difference is very small, perhaps undetectable.
Some old AMD "K6 3D+" processors are noticably slower when %fs is used
rather than %gs; I have no idea why this might be, but I think they're
sufficiently rare that it doesn't matter much.

This patch also fixes the math emulator, which had not been adjusted to
match the changed struct pt_regs.

[frederik.deweerdt@gmail.com: fixit with gdb]
[mingo@elte.hu: Fix KVM too]

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Ian Campbell <Ian.Campbell@XenSource.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Zachary Amsden <zach@vmware.com>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
This commit is contained in:
Jeremy Fitzhardinge 2007-02-13 13:26:20 +01:00 committed by Andi Kleen
parent 54413927f0
commit 464d1a78fb
17 changed files with 99 additions and 103 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/i386/kernel/asm-offsets.c
View File

@ -72,7 +72,7 @@ void foo(void)
OFFSET(PT_EAX, pt_regs, eax);
OFFSET(PT_DS, pt_regs, xds);
OFFSET(PT_ES, pt_regs, xes);
OFFSET(PT_GS, pt_regs, xgs);
OFFSET(PT_FS, pt_regs, xfs);
OFFSET(PT_ORIG_EAX, pt_regs, orig_eax);
OFFSET(PT_EIP, pt_regs, eip);
OFFSET(PT_CS, pt_regs, xcs);

14
arch/i386/kernel/cpu/common.c
View File

@ -605,7 +605,7 @@ void __init early_cpu_init(void)
struct pt_regs * __devinit idle_regs(struct pt_regs *regs)
{
memset(regs, 0, sizeof(struct pt_regs));
regs->xgs = __KERNEL_PDA;
regs->xfs = __KERNEL_PDA;
return regs;
}
@ -662,12 +662,12 @@ struct i386_pda boot_pda = {
.pcurrent = &init_task,
};
static inline void set_kernel_gs(void)
static inline void set_kernel_fs(void)
{
/* Set %gs for this CPU's PDA. Memory clobber is to create a
/* Set %fs for this CPU's PDA. Memory clobber is to create a
barrier with respect to any PDA operations, so the compiler
doesn't move any before here. */
asm volatile ("mov %0, %%gs" : : "r" (__KERNEL_PDA) : "memory");
asm volatile ("mov %0, %%fs" : : "r" (__KERNEL_PDA) : "memory");
}
/* Initialize the CPU's GDT and PDA. The boot CPU does this for
@ -718,7 +718,7 @@ void __cpuinit cpu_set_gdt(int cpu)
the boot CPU, this will transition from the boot gdt+pda to
the real ones). */
load_gdt(cpu_gdt_descr);
set_kernel_gs();
set_kernel_fs();
}
/* Common CPU init for both boot and secondary CPUs */
@ -764,8 +764,8 @@ static void __cpuinit _cpu_init(int cpu, struct task_struct *curr)
__set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
#endif
/* Clear %fs. */
asm volatile ("mov %0, %%fs" : : "r" (0));
/* Clear %gs. */
asm volatile ("mov %0, %%gs" : : "r" (0));
/* Clear all 6 debug registers: */
set_debugreg(0, 0);

32
arch/i386/kernel/entry.S
View File

@ -30,7 +30,7 @@
* 18(%esp) - %eax
* 1C(%esp) - %ds
* 20(%esp) - %es
* 24(%esp) - %gs
* 24(%esp) - %fs
* 28(%esp) - orig_eax
* 2C(%esp) - %eip
* 30(%esp) - %cs
@ -99,9 +99,9 @@ VM_MASK = 0x00020000
#define SAVE_ALL \
cld; \
pushl %gs; \
pushl %fs; \
CFI_ADJUST_CFA_OFFSET 4;\
/*CFI_REL_OFFSET gs, 0;*/\
/*CFI_REL_OFFSET fs, 0;*/\
pushl %es; \
CFI_ADJUST_CFA_OFFSET 4;\
/*CFI_REL_OFFSET es, 0;*/\
@ -133,7 +133,7 @@ VM_MASK = 0x00020000
movl %edx, %ds; \
movl %edx, %es; \
movl $(__KERNEL_PDA), %edx; \
movl %edx, %gs
movl %edx, %fs
#define RESTORE_INT_REGS \
popl %ebx; \
@ -166,9 +166,9 @@ VM_MASK = 0x00020000
2: popl %es; \
CFI_ADJUST_CFA_OFFSET -4;\
/*CFI_RESTORE es;*/\
3: popl %gs; \
3: popl %fs; \
CFI_ADJUST_CFA_OFFSET -4;\
/*CFI_RESTORE gs;*/\
/*CFI_RESTORE fs;*/\
.pushsection .fixup,"ax"; \
4: movl $0,(%esp); \
jmp 1b; \
@ -349,11 +349,11 @@ sysenter_past_esp:
movl PT_OLDESP(%esp), %ecx
xorl %ebp,%ebp
TRACE_IRQS_ON
1: mov PT_GS(%esp), %gs
1: mov PT_FS(%esp), %fs
ENABLE_INTERRUPTS_SYSEXIT
CFI_ENDPROC
.pushsection .fixup,"ax"
2: movl $0,PT_GS(%esp)
2: movl $0,PT_FS(%esp)
jmp 1b
.section __ex_table,"a"
.align 4
@ -550,7 +550,7 @@ syscall_badsys:
#define FIXUP_ESPFIX_STACK \
/* since we are on a wrong stack, we cant make it a C code :( */ \
movl %gs:PDA_cpu, %ebx; \
movl %fs:PDA_cpu, %ebx; \
PER_CPU(cpu_gdt_descr, %ebx); \
movl GDS_address(%ebx), %ebx; \
GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah); \
@ -632,7 +632,7 @@ KPROBE_ENTRY(page_fault)
CFI_ADJUST_CFA_OFFSET 4
ALIGN
error_code:
/* the function address is in %gs's slot on the stack */
/* the function address is in %fs's slot on the stack */
pushl %es
CFI_ADJUST_CFA_OFFSET 4
/*CFI_REL_OFFSET es, 0*/
@ -661,20 +661,20 @@ error_code:
CFI_ADJUST_CFA_OFFSET 4
CFI_REL_OFFSET ebx, 0
cld
pushl %gs
pushl %fs
CFI_ADJUST_CFA_OFFSET 4
/*CFI_REL_OFFSET gs, 0*/
/*CFI_REL_OFFSET fs, 0*/
movl $(__KERNEL_PDA), %ecx
movl %ecx, %gs
movl %ecx, %fs
UNWIND_ESPFIX_STACK
popl %ecx
CFI_ADJUST_CFA_OFFSET -4
/*CFI_REGISTER es, ecx*/
movl PT_GS(%esp), %edi # get the function address
movl PT_FS(%esp), %edi # get the function address
movl PT_ORIG_EAX(%esp), %edx # get the error code
movl $-1, PT_ORIG_EAX(%esp) # no syscall to restart
mov %ecx, PT_GS(%esp)
/*CFI_REL_OFFSET gs, ES*/
mov %ecx, PT_FS(%esp)
/*CFI_REL_OFFSET fs, ES*/
movl $(__USER_DS), %ecx
movl %ecx, %ds
movl %ecx, %es

6
arch/i386/kernel/head.S
View File

@ -319,12 +319,12 @@ is386: movl $2,%ecx # set MP
movl %eax,%ds
movl %eax,%es
xorl %eax,%eax # Clear FS and LDT
movl %eax,%fs
xorl %eax,%eax # Clear GS and LDT
movl %eax,%gs
lldt %ax
movl $(__KERNEL_PDA),%eax
mov %eax,%gs
mov %eax,%fs
cld # gcc2 wants the direction flag cleared at all times
pushl $0 # fake return address for unwinder

4
arch/i386/kernel/kprobes.c
View File

@ -363,7 +363,7 @@ no_kprobe:
" pushf\n"
/* skip cs, eip, orig_eax */
" subl $12, %esp\n"
" pushl %gs\n"
" pushl %fs\n"
" pushl %ds\n"
" pushl %es\n"
" pushl %eax\n"
@ -387,7 +387,7 @@ no_kprobe:
" popl %edi\n"
" popl %ebp\n"
" popl %eax\n"
/* skip eip, orig_eax, es, ds, gs */
/* skip eip, orig_eax, es, ds, fs */
" addl $20, %esp\n"
" popf\n"
" ret\n");

24
arch/i386/kernel/process.c
View File

@ -308,8 +308,8 @@ void show_regs(struct pt_regs * regs)
regs->eax,regs->ebx,regs->ecx,regs->edx);
printk("ESI: %08lx EDI: %08lx EBP: %08lx",
regs->esi, regs->edi, regs->ebp);
printk(" DS: %04x ES: %04x GS: %04x\n",
0xffff & regs->xds,0xffff & regs->xes, 0xffff & regs->xgs);
printk(" DS: %04x ES: %04x FS: %04x\n",
0xffff & regs->xds,0xffff & regs->xes, 0xffff & regs->xfs);
cr0 = read_cr0();
cr2 = read_cr2();
@ -340,7 +340,7 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
regs.xds = __USER_DS;
regs.xes = __USER_DS;
regs.xgs = __KERNEL_PDA;
regs.xfs = __KERNEL_PDA;
regs.orig_eax = -1;
regs.eip = (unsigned long) kernel_thread_helper;
regs.xcs = __KERNEL_CS | get_kernel_rpl();
@ -425,7 +425,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long esp,
p->thread.eip = (unsigned long) ret_from_fork;
savesegment(fs,p->thread.fs);
savesegment(gs,p->thread.gs);
tsk = current;
if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
@ -501,8 +501,8 @@ void dump_thread(struct pt_regs * regs, struct user * dump)
dump->regs.eax = regs->eax;
dump->regs.ds = regs->xds;
dump->regs.es = regs->xes;
savesegment(fs,dump->regs.fs);
dump->regs.gs = regs->xgs;
dump->regs.fs = regs->xfs;
savesegment(gs,dump->regs.gs);
dump->regs.orig_eax = regs->orig_eax;
dump->regs.eip = regs->eip;
dump->regs.cs = regs->xcs;
@ -653,7 +653,7 @@ struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct tas
load_esp0(tss, next);
/*
* Save away %fs. No need to save %gs, as it was saved on the
* Save away %gs. No need to save %fs, as it was saved on the
* stack on entry. No need to save %es and %ds, as those are
* always kernel segments while inside the kernel. Doing this
* before setting the new TLS descriptors avoids the situation
@ -662,7 +662,7 @@ struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct tas
* used %fs or %gs (it does not today), or if the kernel is
* running inside of a hypervisor layer.
*/
savesegment(fs, prev->fs);
savesegment(gs, prev->gs);
/*
* Load the per-thread Thread-Local Storage descriptor.
@ -670,12 +670,10 @@ struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct tas
load_TLS(next, cpu);
/*
* Restore %fs if needed.
*
* Glibc normally makes %fs be zero.
* Restore %gs if needed (which is common)
*/
if (unlikely(prev->fs | next->fs))
loadsegment(fs, next->fs);
if (prev->gs | next->gs)
loadsegment(gs, next->gs);
write_pda(pcurrent, next_p);

16
arch/i386/kernel/ptrace.c
View File

@ -89,14 +89,14 @@ static int putreg(struct task_struct *child,
unsigned long regno, unsigned long value)
{
switch (regno >> 2) {
case FS:
case GS:
if (value && (value & 3) != 3)
return -EIO;
child->thread.fs = value;
child->thread.gs = value;
return 0;
case DS:
case ES:
case GS:
case FS:
if (value && (value & 3) != 3)
return -EIO;
value &= 0xffff;
@ -112,7 +112,7 @@ static int putreg(struct task_struct *child,
value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK;
break;
}
if (regno > ES*4)
if (regno > FS*4)
regno -= 1*4;
put_stack_long(child, regno, value);
return 0;
@ -124,18 +124,18 @@ static unsigned long getreg(struct task_struct *child,
unsigned long retval = ~0UL;
switch (regno >> 2) {
case FS:
retval = child->thread.fs;
case GS:
retval = child->thread.gs;
break;
case DS:
case ES:
case GS:
case FS:
case SS:
case CS:
retval = 0xffff;
/* fall through */
default:
if (regno > ES*4)
if (regno > FS*4)
regno -= 1*4;
retval &= get_stack_long(child, regno);
}

10
arch/i386/kernel/signal.c
View File

@ -128,8 +128,8 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax
X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \
X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF)
COPY_SEG(gs);
GET_SEG(fs);
GET_SEG(gs);
COPY_SEG(fs);
COPY_SEG(es);
COPY_SEG(ds);
COPY(edi);
@ -244,9 +244,9 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
{
int tmp, err = 0;
err |= __put_user(regs->xgs, (unsigned int __user *)&sc->gs);
savesegment(fs, tmp);
err |= __put_user(tmp, (unsigned int __user *)&sc->fs);
err |= __put_user(regs->xfs, (unsigned int __user *)&sc->fs);
savesegment(gs, tmp);
err |= __put_user(tmp, (unsigned int __user *)&sc->gs);
err |= __put_user(regs->xes, (unsigned int __user *)&sc->es);
err |= __put_user(regs->xds, (unsigned int __user *)&sc->ds);

7
arch/i386/kernel/traps.c
View File

@ -291,10 +291,11 @@ void show_registers(struct pt_regs *regs)
int i;
int in_kernel = 1;
unsigned long esp;
unsigned short ss;
unsigned short ss, gs;
esp = (unsigned long) (&regs->esp);
savesegment(ss, ss);
savesegment(gs, gs);
if (user_mode_vm(regs)) {
in_kernel = 0;
esp = regs->esp;
@ -313,8 +314,8 @@ void show_registers(struct pt_regs *regs)
regs->eax, regs->ebx, regs->ecx, regs->edx);
printk(KERN_EMERG "esi: %08lx edi: %08lx ebp: %08lx esp: %08lx\n",
regs->esi, regs->edi, regs->ebp, esp);
printk(KERN_EMERG "ds: %04x es: %04x ss: %04x\n",
regs->xds & 0xffff, regs->xes & 0xffff, ss);
printk(KERN_EMERG "ds: %04x es: %04x fs: %04x gs: %04x ss: %04x\n",
regs->xds & 0xffff, regs->xes & 0xffff, regs->xfs & 0xffff, gs, ss);
printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)",
TASK_COMM_LEN, current->comm, current->pid,
current_thread_info(), current, current->thread_info);

33
arch/i386/kernel/vm86.c
View File

@ -96,12 +96,12 @@ static int copy_vm86_regs_to_user(struct vm86_regs __user *user,
{
int ret = 0;
/* kernel_vm86_regs is missing xfs, so copy everything up to
(but not including) xgs, and then rest after xgs. */
ret += copy_to_user(user, regs, offsetof(struct kernel_vm86_regs, pt.xgs));
ret += copy_to_user(&user->__null_gs, &regs->pt.xgs,
/* kernel_vm86_regs is missing xgs, so copy everything up to
(but not including) orig_eax, and then rest including orig_eax. */
ret += copy_to_user(user, regs, offsetof(struct kernel_vm86_regs, pt.orig_eax));
ret += copy_to_user(&user->orig_eax, &regs->pt.orig_eax,
sizeof(struct kernel_vm86_regs) -
offsetof(struct kernel_vm86_regs, pt.xgs));
offsetof(struct kernel_vm86_regs, pt.orig_eax));
return ret;
}
@ -113,12 +113,13 @@ static int copy_vm86_regs_from_user(struct kernel_vm86_regs *regs,
{
int ret = 0;
ret += copy_from_user(regs, user, offsetof(struct kernel_vm86_regs, pt.xgs));
ret += copy_from_user(&regs->pt.xgs, &user->__null_gs,
/* copy eax-xfs inclusive */
ret += copy_from_user(regs, user, offsetof(struct kernel_vm86_regs, pt.orig_eax));
/* copy orig_eax-__gsh+extra */
ret += copy_from_user(&regs->pt.orig_eax, &user->orig_eax,
sizeof(struct kernel_vm86_regs) -
offsetof(struct kernel_vm86_regs, pt.xgs) +
offsetof(struct kernel_vm86_regs, pt.orig_eax) +
extra);
return ret;
}
@ -157,8 +158,8 @@ struct pt_regs * fastcall save_v86_state(struct kernel_vm86_regs * regs)
ret = KVM86->regs32;
loadsegment(fs, current->thread.saved_fs);
ret->xgs = current->thread.saved_gs;
ret->xfs = current->thread.saved_fs;
loadsegment(gs, current->thread.saved_gs);
return ret;
}
@ -285,9 +286,9 @@ static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct *tsk
*/
info->regs.pt.xds = 0;
info->regs.pt.xes = 0;
info->regs.pt.xgs = 0;
info->regs.pt.xfs = 0;
/* we are clearing fs later just before "jmp resume_userspace",
/* we are clearing gs later just before "jmp resume_userspace",
* because it is not saved/restored.
*/
@ -321,8 +322,8 @@ static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct *tsk
*/
info->regs32->eax = 0;
tsk->thread.saved_esp0 = tsk->thread.esp0;
savesegment(fs, tsk->thread.saved_fs);
tsk->thread.saved_gs = info->regs32->xgs;
tsk->thread.saved_fs = info->regs32->xfs;
savesegment(gs, tsk->thread.saved_gs);
tss = &per_cpu(init_tss, get_cpu());
tsk->thread.esp0 = (unsigned long) &info->VM86_TSS_ESP0;
@ -342,7 +343,7 @@ static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct *tsk
__asm__ __volatile__(
"movl %0,%%esp\n\t"
"movl %1,%%ebp\n\t"
"mov %2, %%fs\n\t"
"mov %2, %%gs\n\t"
"jmp resume_userspace"
: /* no outputs */
:"r" (&info->regs), "r" (task_thread_info(tsk)), "r" (0));

14
arch/i386/math-emu/get_address.c
View File

@ -56,15 +56,14 @@ static int reg_offset_vm86[] = {
#define VM86_REG_(x) (*(unsigned short *) \
(reg_offset_vm86[((unsigned)x)]+(u_char *) FPU_info))
/* These are dummy, fs and gs are not saved on the stack. */
#define ___FS ___ds
/* This dummy, gs is not saved on the stack. */
#define ___GS ___ds
static int reg_offset_pm[] = {
offsetof(struct info,___cs),
offsetof(struct info,___ds),
offsetof(struct info,___es),
offsetof(struct info,___FS),
offsetof(struct info,___fs),
offsetof(struct info,___GS),
offsetof(struct info,___ss),
offsetof(struct info,___ds)
@ -169,13 +168,10 @@ static long pm_address(u_char FPU_modrm, u_char segment,
switch ( segment )
{
/* fs and gs aren't used by the kernel, so they still have their
user-space values. */
case PREFIX_FS_-1:
/* N.B. - movl %seg, mem is a 2 byte write regardless of prefix */
savesegment(fs, addr->selector);
break;
/* gs isn't used by the kernel, so it still has its
user-space value. */
case PREFIX_GS_-1:
/* N.B. - movl %seg, mem is a 2 byte write regardless of prefix */
savesegment(gs, addr->selector);
break;
default:

12
drivers/kvm/vmx.c
View File

@ -1879,12 +1879,6 @@ again:
asm ("mov %0, %%ds; mov %0, %%es" : : "r"(__USER_DS));
/*
* Profile KVM exit RIPs:
*/
if (unlikely(prof_on == KVM_PROFILING))
profile_hit(KVM_PROFILING, (void *)vmcs_readl(GUEST_RIP));
kvm_run->exit_type = 0;
if (fail) {
kvm_run->exit_type = KVM_EXIT_TYPE_FAIL_ENTRY;
@ -1907,6 +1901,12 @@ again:
reload_tss();
}
/*
* Profile KVM exit RIPs:
*/
if (unlikely(prof_on == KVM_PROFILING))
profile_hit(KVM_PROFILING, (void *)vmcs_readl(GUEST_RIP));
vcpu->launched = 1;
kvm_run->exit_type = KVM_EXIT_TYPE_VM_EXIT;
r = kvm_handle_exit(kvm_run, vcpu);

4
include/asm-i386/elf.h
View File

@ -90,8 +90,8 @@ typedef struct user_fxsr_struct elf_fpxregset_t;
pr_reg[6] = regs->eax; \
pr_reg[7] = regs->xds; \
pr_reg[8] = regs->xes; \
savesegment(fs,pr_reg[9]); \
pr_reg[10] = regs->xgs; \
pr_reg[9] = regs->xfs; \
savesegment(gs,pr_reg[10]); \
pr_reg[11] = regs->orig_eax; \
pr_reg[12] = regs->eip; \
pr_reg[13] = regs->xcs; \

2
include/asm-i386/mmu_context.h
View File

@ -63,7 +63,7 @@ static inline void switch_mm(struct mm_struct *prev,
}
#define deactivate_mm(tsk, mm) \
asm("movl %0,%%fs": :"r" (0));
asm("movl %0,%%gs": :"r" (0));
#define activate_mm(prev, next) \
switch_mm((prev),(next),NULL)

12
include/asm-i386/pda.h
View File

@ -39,19 +39,19 @@ extern struct i386_pda _proxy_pda;
if (0) { T__ tmp__; tmp__ = (val); } \
switch (sizeof(_proxy_pda.field)) { \
case 1: \
asm(op "b %1,%%gs:%c2" \
asm(op "b %1,%%fs:%c2" \
: "+m" (_proxy_pda.field) \
:"ri" ((T__)val), \
"i"(pda_offset(field))); \
break; \
case 2: \
asm(op "w %1,%%gs:%c2" \
asm(op "w %1,%%fs:%c2" \
: "+m" (_proxy_pda.field) \
:"ri" ((T__)val), \
"i"(pda_offset(field))); \
break; \
case 4: \
asm(op "l %1,%%gs:%c2" \
asm(op "l %1,%%fs:%c2" \
: "+m" (_proxy_pda.field) \
:"ri" ((T__)val), \
"i"(pda_offset(field))); \
@ -65,19 +65,19 @@ extern struct i386_pda _proxy_pda;
typeof(_proxy_pda.field) ret__; \
switch (sizeof(_proxy_pda.field)) { \
case 1: \
asm(op "b %%gs:%c1,%0" \
asm(op "b %%fs:%c1,%0" \
: "=r" (ret__) \
: "i" (pda_offset(field)), \
"m" (_proxy_pda.field)); \
break; \
case 2: \
asm(op "w %%gs:%c1,%0" \
asm(op "w %%fs:%c1,%0" \
: "=r" (ret__) \
: "i" (pda_offset(field)), \
"m" (_proxy_pda.field)); \
break; \
case 4: \
asm(op "l %%gs:%c1,%0" \
asm(op "l %%fs:%c1,%0" \
: "=r" (ret__) \
: "i" (pda_offset(field)), \
"m" (_proxy_pda.field)); \

6
include/asm-i386/processor.h
View File

@ -424,7 +424,7 @@ struct thread_struct {
.vm86_info = NULL, \
.sysenter_cs = __KERNEL_CS, \
.io_bitmap_ptr = NULL, \
.gs = __KERNEL_PDA, \
.fs = __KERNEL_PDA, \
}
/*
@ -442,8 +442,8 @@ struct thread_struct {
}
#define start_thread(regs, new_eip, new_esp) do { \
__asm__("movl %0,%%fs": :"r" (0)); \
regs->xgs = 0; \
__asm__("movl %0,%%gs": :"r" (0)); \
regs->xfs = 0; \
set_fs(USER_DS); \
regs->xds = __USER_DS; \
regs->xes = __USER_DS; \

4
include/asm-i386/ptrace.h
View File

@ -16,8 +16,8 @@ struct pt_regs {
long eax;
int xds;
int xes;
/* int xfs; */
int xgs;
int xfs;
/* int xgs; */
long orig_eax;
long eip;
int xcs;