Attachment 311624 Details for Bug 455095 – use passed in edx register on i386

[patch] use passed in edx register on i386

event-tracer-i386-fix.patch (text/plain), 2.35 KB, created by Steven Rostedt on 2008-07-11 22:56:06 UTC

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Creator: Steven Rostedt

Created: 2008-07-11 22:56:06 UTC

Size: 2.35 KB

patch

obsolete

>From: Steven Rostedt <srostedt@redhat.com>
>Subject: event_trace: fix syscall functions
>
>The syscall trace functions in i386 has a bad %edx because the SAVE_ALL
>modifies it after saving it to the stack. This means the third parameter
>passed to the system call is not the same as what is being passed to the
>tracer.
>
>This patch also fixes the CONFIG define to from CONFIG_EVENT_TRACE to
>CONFIG_EVENT_TRACER, as well as adds a label before the call to sys_call
>to make a nicer output from the tracer.
>
>Signed-off-by: Steven Rostedt <srostedt@redhat.com>
>---
> arch/x86/kernel/entry_32.S |   20 +++++++++++++++++---
> 1 file changed, 17 insertions(+), 3 deletions(-)
>
>Index: linux-2.6.24.7-rt14/arch/x86/kernel/entry_32.S
>===================================================================
>--- linux-2.6.24.7-rt14.orig/arch/x86/kernel/entry_32.S	2008-07-11 17:45:34.000000000 -0400
>+++ linux-2.6.24.7-rt14/arch/x86/kernel/entry_32.S	2008-07-11 17:47:57.000000000 -0400
>@@ -334,10 +334,14 @@ sysenter_past_esp:
> 	pushl %eax
> 	CFI_ADJUST_CFA_OFFSET 4
> 	SAVE_ALL
>-#ifdef CONFIG_EVENT_TRACE
>+#ifdef CONFIG_EVENT_TRACER
>+	pushl %edx
>+	movl 8(%esp), %edx
> 	pushl %edx; pushl %ecx; pushl %ebx; pushl %eax
>+sysenter_enter:		/* label for event tracer */
> 	call sys_call
> 	popl %eax; popl %ebx; popl %ecx; popl %edx
>+	popl %edx
> #endif
> 	GET_THREAD_INFO(%ebp)
> 
>@@ -354,8 +358,9 @@ sysenter_past_esp:
> 	movl TI_flags(%ebp), %ecx
> 	testw $_TIF_ALLWORK_MASK, %cx
> 	jne syscall_exit_work
>-#ifdef CONFIG_EVENT_TRACE
>+#ifdef CONFIG_EVENT_TRACER
> 	pushl %eax
>+sysenter_return:	/* label for event tracer */
> 	call sys_ret
> 	popl %eax
> #endif
>@@ -382,10 +387,14 @@ ENTRY(system_call)
> 	pushl %eax			# save orig_eax
> 	CFI_ADJUST_CFA_OFFSET 4
> 	SAVE_ALL
>-#ifdef CONFIG_EVENT_TRACE
>+#ifdef CONFIG_EVENT_TRACER
>+	pushl %edx
>+	/* edx has fs, so get it from the stack */
>+	movl 8(%esp), %edx
> 	pushl %edx; pushl %ecx; pushl %ebx; pushl %eax
> 	call sys_call
> 	popl %eax; popl %ebx; popl %ecx; popl %edx
>+	popl %edx
> #endif
> 	GET_THREAD_INFO(%ebp)
> 					# system call tracing in operation / emulation
>@@ -398,6 +407,11 @@ syscall_call:
> 	call *sys_call_table(,%eax,4)
> 	movl %eax,PT_EAX(%esp)		# store the return value
> syscall_exit:
>+#ifdef CONFIG_EVENT_TRACER
>+	pushl %eax
>+	call sys_ret
>+	popl %eax
>+#endif
> 	LOCKDEP_SYS_EXIT
> 	DISABLE_INTERRUPTS(CLBR_ANY)	# make sure we don't miss an interrupt
> 					# setting need_resched or sigpending

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Attachments on bug 455095: 311623 | 311624 | 325706