X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;ds=sidebyside;f=arch%2Fi386%2Fkernel%2Fentry.S;h=840d990b83da862c7c05ab28f7f4759ee84b40a5;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=a991d4e5edd247c962b49d5d288d052183b7c138;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git

diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
index a991d4e5e..840d990b8 100644
--- a/arch/i386/kernel/entry.S
+++ b/arch/i386/kernel/entry.S
@@ -184,8 +184,12 @@ sysenter_past_esp:
 	pushl %ebp
 	pushfl
 	pushl $(__USER_CS)
-	pushl $SYSENTER_RETURN
-
+	/*
+	 * 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)
 /*
  * Load the potential sixth argument from user stack.
  * Careful about security.
@@ -203,7 +207,7 @@ sysenter_past_esp:
 	GET_THREAD_INFO(%ebp)
 
 	/* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
-	testw $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),TI_flags(%ebp)
+	testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
 	jnz syscall_trace_entry
 	cmpl $(nr_syscalls), %eax
 	jae syscall_badsys
@@ -226,9 +230,13 @@ ENTRY(system_call)
 	pushl %eax			# save orig_eax
 	SAVE_ALL
 	GET_THREAD_INFO(%ebp)
-					# system call tracing in operation
+	testl $TF_MASK,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_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),TI_flags(%ebp)
+	testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
 	jnz syscall_trace_entry
 	cmpl $(nr_syscalls), %eax
 	jae syscall_badsys
@@ -319,17 +327,19 @@ work_notifysig:				# deal with pending signals and
 					# vm86-space
 	xorl %edx, %edx
 	call do_notify_resume
-	jmp restore_all
+	jmp resume_userspace
 
 	ALIGN
 work_notifysig_v86:
+#ifdef CONFIG_VM86
 	pushl %ecx			# save ti_flags for do_notify_resume
 	call save_v86_state		# %eax contains pt_regs pointer
 	popl %ecx
 	movl %eax, %esp
 	xorl %edx, %edx
 	call do_notify_resume
-	jmp restore_all
+	jmp resume_userspace
+#endif
 
 	# perform syscall exit tracing
 	ALIGN
@@ -338,6 +348,9 @@ syscall_trace_entry:
 	movl %esp, %eax
 	xorl %edx,%edx
 	call do_syscall_trace
+	cmpl $0, %eax
+	jne resume_userspace		# ret != 0 -> running under PTRACE_SYSEMU,
+					# so must skip actual syscall
 	movl ORIG_EAX(%esp), %eax
 	cmpl $(nr_syscalls), %eax
 	jnae syscall_call
@@ -504,7 +517,7 @@ label:						\
 	pushl $__KERNEL_CS;			\
 	pushl $sysenter_past_esp
 
-ENTRY(debug)
+KPROBE_ENTRY(debug)
 	cmpl $sysenter_entry,(%esp)
 	jne debug_stack_correct
 	FIX_STACK(12, debug_stack_correct, debug_esp_fix_insn)
@@ -515,7 +528,7 @@ debug_stack_correct:
 	movl %esp,%eax			# pt_regs pointer
 	call do_debug
 	jmp ret_from_exception
-
+	.previous .text
 /*
  * NMI is doubly nasty. It can happen _while_ we're handling
  * a debug fault, and the debug fault hasn't yet been able to
@@ -557,11 +570,10 @@ nmi_stack_fixup:
 nmi_debug_stack_check:
 	cmpw $__KERNEL_CS,16(%esp)
 	jne nmi_stack_correct
-	cmpl $debug - 1,(%esp)
-	jle nmi_stack_correct
+	cmpl $debug,(%esp)
+	jb nmi_stack_correct
 	cmpl $debug_esp_fix_insn,(%esp)
-	jle nmi_debug_stack_fixup
-nmi_debug_stack_fixup:
+	ja nmi_stack_correct
 	FIX_STACK(24,nmi_stack_correct, 1)
 	jmp nmi_stack_correct
 
@@ -588,13 +600,14 @@ nmi_16bit_stack:
 	.long 1b,iret_exc
 .previous
 
-ENTRY(int3)
+KPROBE_ENTRY(int3)
 	pushl $-1			# mark this as an int
 	SAVE_ALL
 	xorl %edx,%edx		# zero error code
 	movl %esp,%eax		# pt_regs pointer
 	call do_int3
 	jmp ret_from_exception
+	.previous .text
 
 ENTRY(overflow)
 	pushl $0
@@ -628,17 +641,19 @@ ENTRY(stack_segment)
 	pushl $do_stack_segment
 	jmp error_code
 
-ENTRY(general_protection)
+KPROBE_ENTRY(general_protection)
 	pushl $do_general_protection
 	jmp error_code
+	.previous .text
 
 ENTRY(alignment_check)
 	pushl $do_alignment_check
 	jmp error_code
 
-ENTRY(page_fault)
+KPROBE_ENTRY(page_fault)
 	pushl $do_page_fault
 	jmp error_code
+	.previous .text
 
 #ifdef CONFIG_X86_MCE
 ENTRY(machine_check)
@@ -652,6 +667,7 @@ ENTRY(spurious_interrupt_bug)
 	pushl $do_spurious_interrupt_bug
 	jmp error_code
 
+.section .rodata,"a"
 #include "syscall_table.S"
 
 syscall_table_size=(.-sys_call_table)