PERFORCE change 92094 for review

[John Baldwin]

http://perforce.freebsd.org/chv.cgi?CH=92094

Change 92094 by jhb at jhb_slimer on 2006/02/20 21:16:54

	ptrace_clear_single_step() needs callers to hold the proc lock
	and PHOLD/PRELE.

Affected files ...

.. //depot/projects/smpng/sys/alpha/alpha/trap.c#63 edit
.. //depot/projects/smpng/sys/alpha/include/ptrace.h#9 edit
.. //depot/projects/smpng/sys/arm/arm/undefined.c#10 edit
.. //depot/projects/smpng/sys/kern/kern_kse.c#29 edit

Differences ...

==== //depot/projects/smpng/sys/alpha/alpha/trap.c#63 (text+ko) ====

@@ -405,8 +405,12 @@
 		case ALPHA_IF_CODE_BUGCHK:
 			if (td->td_md.md_flags & (MDTD_STEP1|MDTD_STEP2)) {
 				mtx_lock(&Giant);
+				PROC_LOCK(p);
+				_PHOLD(p);
 				ptrace_clear_single_step(td);
 				td->td_frame->tf_regs[FRAME_PC] -= 4;
+				_PRELE(p);
+				PROC_UNLOCK(p);
 				mtx_unlock(&Giant);
 			}
 			ucode = a0;		/* trap type */

==== //depot/projects/smpng/sys/alpha/include/ptrace.h#9 (text+ko) ====

@@ -34,7 +34,11 @@
 #define _MACHINE_PTRACE_H_
 
 #ifdef _KERNEL
-#define FIX_SSTEP(p)	ptrace_clear_single_step(p)
+#define FIX_SSTEP(p) do {						\
+	_PHOLD((p));							\
+	ptrace_clear_single_step((p));					\
+	_PRELE((p));							\
+} while (0)
 #endif
 
 #endif

==== //depot/projects/smpng/sys/arm/arm/undefined.c#10 (text+ko) ====

@@ -261,7 +261,11 @@
 		    break;
 
 	if (fault_code & FAULT_USER && fault_instruction == PTRACE_BREAKPOINT) {
+		PROC_LOCK(td->td_proc);
+		_PHOLD(td->td_proc);
 		ptrace_clear_single_step(td);
+		_PRELE(td->td_proc);
+		PROC_UNLOCK(td->td_proc);
 		return;
 	}
 

==== //depot/projects/smpng/sys/kern/kern_kse.c#29 (text+ko) ====

@@ -787,8 +787,13 @@
 			 */
 			cpu_set_upcall_kse(newtd, newku->ku_func,
 				newku->ku_mailbox, &newku->ku_stack);
-			if (p->p_flag & P_TRACED)
+			PROC_LOCK(p);
+			if (p->p_flag & P_TRACED) {
+				_PHOLD(p);
 				ptrace_clear_single_step(newtd);
+				_PRELE(p);
+			}
+			PROC_UNLOCK(p);
 		}
 	}
 	
@@ -1381,8 +1386,13 @@
 		if (!(ku->ku_mflags & KMF_NOUPCALL)) {
 			cpu_set_upcall_kse(td, ku->ku_func, ku->ku_mailbox,
 				&ku->ku_stack);
-			if (p->p_flag & P_TRACED)
+			PROC_LOCK(p);
+			if (p->p_flag & P_TRACED) {
+				_PHOLD(p);
 				ptrace_clear_single_step(td);
+				_PRELE(p);
+			}
+			PROC_UNLOCK(p);
 			error = suword32(&ku->ku_mailbox->km_lwp,
 					td->td_tid);
 			if (error)