From 90f9d70a582c02f50b4dd847166cd5b037219891 Mon Sep 17 00:00:00 2001 From: "bibo,mao" Date: Wed, 31 Jan 2007 17:50:31 +0800 Subject: [IA64] enable singlestep on system call As is pointed out in http://www.gelato.org/community/view_linear.php?id=1_1036&from=authors&value=Ian%20Wienand#1_1039, if single step on break instruction, the break fault has higher priority than the single-step trap. When the break fault handler is entered, it advances the IP by 1 instruction so break instruction single-stepping is skipped, actually it is next instruction which is single stepped. This patch modifies this, it adds TIF_SINGLESTEP bit for thread flags, and generate a fake sigtrap when single stepping break instruction. Test case in attachment can verify this. Any comments is welcome. Signed-off-by: bibo, mao Signed-off-by: Tony Luck --- include/asm-ia64/thread_info.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/asm-ia64') diff --git a/include/asm-ia64/thread_info.h b/include/asm-ia64/thread_info.h index 9b505b25544..91698599f91 100644 --- a/include/asm-ia64/thread_info.h +++ b/include/asm-ia64/thread_info.h @@ -84,6 +84,7 @@ struct thread_info { #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ #define TIF_SYSCALL_TRACE 3 /* syscall trace active */ #define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */ +#define TIF_SINGLESTEP 5 /* restore singlestep on return to user mode */ #define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */ #define TIF_MEMDIE 17 #define TIF_MCA_INIT 18 /* this task is processing MCA or INIT */ @@ -92,7 +93,8 @@ struct thread_info { #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) -#define _TIF_SYSCALL_TRACEAUDIT (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT) +#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) +#define _TIF_SYSCALL_TRACEAUDIT (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) -- cgit v1.2.3