i386: fix regression, endless loop in ptrace singlestep over an int80

[sfrench/cifs-2.6.git] / arch / i386 / kernel / entry.S

diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
index 18bddcb8e9e82757042d4813568120257b9bb25f..3c3c220488c93fe20bd0a26d0553cc941ac7d81f 100644 (file)
--- a/arch/i386/kernel/entry.S
+++ b/arch/i386/kernel/entry.S
@@ -15,7 +15,7 @@
  * I changed all the .align's to 4 (16 byte alignment), as that's faster
  * on a 486.
  *
- * Stack layout in 'ret_from_system_call':
+ * Stack layout in 'syscall_exit':
  *     ptrace needs to have all regs on the stack.
  *     if the order here is changed, it needs to be
  *     updated in fork.c:copy_process, signal.c:do_signal,
@@ -132,7 +132,7 @@ VM_MASK             = 0x00020000
        movl $(__USER_DS), %edx; \
        movl %edx, %ds; \
        movl %edx, %es; \
-       movl $(__KERNEL_PDA), %edx; \
+       movl $(__KERNEL_PERCPU), %edx; \
        movl %edx, %fs
 
 #define RESTORE_INT_REGS \
@@ -305,16 +305,12 @@ sysenter_past_esp:
        pushl $(__USER_CS)
        CFI_ADJUST_CFA_OFFSET 4
        /*CFI_REL_OFFSET cs, 0*/
-#ifndef CONFIG_COMPAT_VDSO
        /*
         * Push current_thread_info()->sysenter_return to the stack.
         * A tiny bit of offset fixup is necessary - 4*4 means the 4 words
         * pushed above; +8 corresponds to copy_thread's esp0 setting.
         */
        pushl (TI_sysenter_return-THREAD_SIZE+8+4*4)(%esp)
-#else
-       pushl $SYSENTER_RETURN
-#endif
        CFI_ADJUST_CFA_OFFSET 4
        CFI_REL_OFFSET eip, 0
 
@@ -342,7 +338,7 @@ sysenter_past_esp:
        jae syscall_badsys
        call *sys_call_table(,%eax,4)
        movl %eax,PT_EAX(%esp)
-       DISABLE_INTERRUPTS(CLBR_ECX|CLBR_EDX)
+       DISABLE_INTERRUPTS(CLBR_ANY)
        TRACE_IRQS_OFF
        movl TI_flags(%ebp), %ecx
        testw $_TIF_ALLWORK_MASK, %cx
@@ -371,10 +367,6 @@ ENTRY(system_call)
        CFI_ADJUST_CFA_OFFSET 4
        SAVE_ALL
        GET_THREAD_INFO(%ebp)
-       testl $TF_MASK,PT_EFLAGS(%esp)
-       jz no_singlestep
-       orl $_TIF_SINGLESTEP,TI_flags(%ebp)
-no_singlestep:
                                        # system call tracing in operation / emulation
        /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
        testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
@@ -389,6 +381,10 @@ syscall_exit:
                                        # setting need_resched or sigpending
                                        # between sampling and the iret
        TRACE_IRQS_OFF
+       testl $TF_MASK,PT_EFLAGS(%esp)  # If tracing set singlestep flag on exit
+       jz no_singlestep
+       orl $_TIF_SINGLESTEP,TI_flags(%ebp)
+no_singlestep:
        movl TI_flags(%ebp), %ecx
        testw $_TIF_ALLWORK_MASK, %cx   # current->work
        jne syscall_exit_work
@@ -560,9 +556,7 @@ END(syscall_badsys)
 
 #define FIXUP_ESPFIX_STACK \
        /* since we are on a wrong stack, we cant make it a C code :( */ \
-       movl %fs:PDA_cpu, %ebx; \
-       PER_CPU(cpu_gdt_descr, %ebx); \
-       movl GDS_address(%ebx), %ebx; \
+       PER_CPU(gdt_page, %ebx); \
        GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah); \
        addl %esp, %eax; \
        pushl $__KERNEL_DS; \
@@ -635,7 +629,7 @@ ENTRY(name)                         \
        SAVE_ALL;                       \
        TRACE_IRQS_OFF                  \
        movl %esp,%eax;                 \
-       call smp_/**/name;              \
+       call smp_##name;                \
        jmp ret_from_intr;              \
        CFI_ENDPROC;                    \
 ENDPROC(name)
@@ -643,11 +637,6 @@ ENDPROC(name)
 /* The include is where all of the SMP etc. interrupts come from */
 #include "entry_arch.h"
 
-/* This alternate entry is needed because we hijack the apic LVTT */
-#if defined(CONFIG_VMI) && defined(CONFIG_X86_LOCAL_APIC)
-BUILD_INTERRUPT(apic_vmi_timer_interrupt,LOCAL_TIMER_VECTOR)
-#endif
-
 KPROBE_ENTRY(page_fault)
        RING0_EC_FRAME
        pushl $do_page_fault
@@ -686,7 +675,7 @@ error_code:
        pushl %fs
        CFI_ADJUST_CFA_OFFSET 4
        /*CFI_REL_OFFSET fs, 0*/
-       movl $(__KERNEL_PDA), %ecx
+       movl $(__KERNEL_PERCPU), %ecx
        movl %ecx, %fs
        UNWIND_ESPFIX_STACK
        popl %ecx