Merge branch 'sii-m15w' into upstream

[pandora-kernel.git] / arch / i386 / kernel / entry.S

diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
index 787190c..37a7d2e 100644 (file)
--- a/arch/i386/kernel/entry.S
+++ b/arch/i386/kernel/entry.S
@@ -42,6 +42,7 @@
 
 #include <linux/linkage.h>
 #include <asm/thread_info.h>
+#include <asm/irqflags.h>
 #include <asm/errno.h>
 #include <asm/segment.h>
 #include <asm/smp.h>
@@ -76,12 +77,21 @@ NT_MASK             = 0x00004000
 VM_MASK                = 0x00020000
 
 #ifdef CONFIG_PREEMPT
-#define preempt_stop           cli
+#define preempt_stop           cli; TRACE_IRQS_OFF
 #else
 #define preempt_stop
 #define resume_kernel          restore_nocheck
 #endif
 
+.macro TRACE_IRQS_IRET
+#ifdef CONFIG_TRACE_IRQFLAGS
+       testl $IF_MASK,EFLAGS(%esp)     # interrupts off?
+       jz 1f
+       TRACE_IRQS_ON
+1:
+#endif
+.endm
+
 #ifdef CONFIG_VM86
 #define resume_userspace_sig   check_userspace
 #else
@@ -194,7 +204,7 @@ VM_MASK             = 0x00020000
 ENTRY(ret_from_fork)
        CFI_STARTPROC
        pushl %eax
-       CFI_ADJUST_CFA_OFFSET -4
+       CFI_ADJUST_CFA_OFFSET 4
        call schedule_tail
        GET_THREAD_INFO(%ebp)
        popl %eax
@@ -257,6 +267,10 @@ ENTRY(sysenter_entry)
        CFI_REGISTER esp, ebp
        movl TSS_sysenter_esp0(%esp),%esp
 sysenter_past_esp:
+       /*
+        * No need to follow this irqs on/off section: the syscall
+        * disabled irqs and here we enable it straight after entry:
+        */
        sti
        pushl $(__USER_DS)
        CFI_ADJUST_CFA_OFFSET 4
@@ -303,6 +317,7 @@ sysenter_past_esp:
        call *sys_call_table(,%eax,4)
        movl %eax,EAX(%esp)
        cli
+       TRACE_IRQS_OFF
        movl TI_flags(%ebp), %ecx
        testw $_TIF_ALLWORK_MASK, %cx
        jne syscall_exit_work
@@ -310,6 +325,7 @@ sysenter_past_esp:
        movl EIP(%esp), %edx
        movl OLDESP(%esp), %ecx
        xorl %ebp,%ebp
+       TRACE_IRQS_ON
        sti
        sysexit
        CFI_ENDPROC
@@ -339,6 +355,7 @@ syscall_exit:
        cli                             # make sure we don't miss an interrupt
                                        # setting need_resched or sigpending
                                        # between sampling and the iret
+       TRACE_IRQS_OFF
        movl TI_flags(%ebp), %ecx
        testw $_TIF_ALLWORK_MASK, %cx   # current->work
        jne syscall_exit_work
@@ -355,12 +372,15 @@ restore_all:
        CFI_REMEMBER_STATE
        je ldt_ss                       # returning to user-space with LDT SS
 restore_nocheck:
+       TRACE_IRQS_IRET
+restore_nocheck_notrace:
        RESTORE_REGS
        addl $4, %esp
        CFI_ADJUST_CFA_OFFSET -4
 1:     iret
 .section .fixup,"ax"
 iret_exc:
+       TRACE_IRQS_ON
        sti
        pushl $0                        # no error code
        pushl $do_iret_error
@@ -386,11 +406,13 @@ ldt_ss:
        subl $8, %esp           # reserve space for switch16 pointer
        CFI_ADJUST_CFA_OFFSET 8
        cli
+       TRACE_IRQS_OFF
        movl %esp, %eax
        /* Set up the 16bit stack frame with switch32 pointer on top,
         * and a switch16 pointer on top of the current frame. */
        call setup_x86_bogus_stack
        CFI_ADJUST_CFA_OFFSET -8        # frame has moved
+       TRACE_IRQS_IRET
        RESTORE_REGS
        lss 20+4(%esp), %esp    # switch to 16bit stack
 1:     iret
@@ -411,6 +433,7 @@ work_resched:
        cli                             # make sure we don't miss an interrupt
                                        # setting need_resched or sigpending
                                        # between sampling and the iret
+       TRACE_IRQS_OFF
        movl TI_flags(%ebp), %ecx
        andl $_TIF_WORK_MASK, %ecx      # is there any work to be done other
                                        # than syscall tracing?
@@ -462,6 +485,7 @@ syscall_trace_entry:
 syscall_exit_work:
        testb $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP), %cl
        jz work_pending
+       TRACE_IRQS_ON
        sti                             # could let do_syscall_trace() call
                                        # schedule() instead
        movl %esp, %eax
@@ -535,9 +559,14 @@ ENTRY(irq_entries_start)
 vector=vector+1
 .endr
 
+/*
+ * the CPU automatically disables interrupts when executing an IRQ vector,
+ * so IRQ-flags tracing has to follow that:
+ */
        ALIGN
 common_interrupt:
        SAVE_ALL
+       TRACE_IRQS_OFF
        movl %esp,%eax
        call do_IRQ
        jmp ret_from_intr
@@ -549,9 +578,10 @@ ENTRY(name)                                \
        pushl $~(nr);                   \
        CFI_ADJUST_CFA_OFFSET 4;        \
        SAVE_ALL;                       \
+       TRACE_IRQS_OFF                  \
        movl %esp,%eax;                 \
        call smp_/**/name;              \
-       jmp ret_from_intr;      \
+       jmp ret_from_intr;              \
        CFI_ENDPROC
 
 /* The include is where all of the SMP etc. interrupts come from */
@@ -726,7 +756,7 @@ nmi_stack_correct:
        xorl %edx,%edx          # zero error code
        movl %esp,%eax          # pt_regs pointer
        call do_nmi
-       jmp restore_all
+       jmp restore_nocheck_notrace
        CFI_ENDPROC
 
 nmi_stack_fixup: