[S390] ptrace changes
* System call parameter and result access functions
* Add tracehook calls
* Split syscall_trace into two functions do_syscall_trace_enter and
do_syscall_trace_exit
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 708cf9c..ed500ef 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -49,9 +49,9 @@
SP_TRAP = STACK_FRAME_OVERHEAD + __PT_TRAP
SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
-_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
-_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING)
STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
@@ -318,6 +318,8 @@
bo BASED(sysc_reschedule)
tm __TI_flags+3(%r9),_TIF_SIGPENDING
bnz BASED(sysc_sigpending)
+ tm __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
+ bnz BASED(sysc_notify_resume)
tm __TI_flags+3(%r9),_TIF_RESTART_SVC
bo BASED(sysc_restart)
tm __TI_flags+3(%r9),_TIF_SINGLE_STEP
@@ -356,6 +358,16 @@
b BASED(sysc_work_loop)
#
+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
+#
+sysc_notify_resume:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ l %r1,BASED(.Ldo_notify_resume)
+ la %r14,BASED(sysc_work_loop)
+ br %r1 # call do_notify_resume
+
+
+#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
@@ -378,20 +390,21 @@
br %r1 # branch to do_single_step
#
-# call trace before and after sys_call
+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
+# and after the system call
#
sysc_tracesys:
- l %r1,BASED(.Ltrace)
+ l %r1,BASED(.Ltrace_entry)
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
srl %r7,2
st %r7,SP_R2(%r15)
basr %r14,%r1
- clc SP_R2(4,%r15),BASED(.Lnr_syscalls)
+ cl %r2,BASED(.Lnr_syscalls)
bnl BASED(sysc_tracenogo)
l %r8,BASED(.Lsysc_table)
- l %r7,SP_R2(%r15) # strace might have changed the
- sll %r7,2 # system call
+ lr %r7,%r2
+ sll %r7,2 # *4
l %r8,0(%r7,%r8)
sysc_tracego:
lm %r3,%r6,SP_R3(%r15)
@@ -401,9 +414,8 @@
sysc_tracenogo:
tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
bz BASED(sysc_return)
- l %r1,BASED(.Ltrace)
+ l %r1,BASED(.Ltrace_exit)
la %r2,SP_PTREGS(%r15) # load pt_regs
- la %r3,1
la %r14,BASED(sysc_return)
br %r1
@@ -666,6 +678,8 @@
bo BASED(io_reschedule)
tm __TI_flags+3(%r9),_TIF_SIGPENDING
bnz BASED(io_sigpending)
+ tm __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
+ bnz BASED(io_notify_resume)
b BASED(io_restore)
io_work_done:
@@ -704,6 +718,19 @@
TRACE_IRQS_OFF
b BASED(io_work_loop)
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+io_notify_resume:
+ TRACE_IRQS_ON
+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ l %r1,BASED(.Ldo_notify_resume)
+ basr %r14,%r1 # call do_signal
+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
+ TRACE_IRQS_OFF
+ b BASED(io_work_loop)
+
/*
* External interrupt handler routine
*/
@@ -1070,6 +1097,8 @@
.Ldo_IRQ: .long do_IRQ
.Ldo_extint: .long do_extint
.Ldo_signal: .long do_signal
+.Ldo_notify_resume:
+ .long do_notify_resume
.Lhandle_per: .long do_single_step
.Ldo_execve: .long do_execve
.Lexecve_tail: .long execve_tail
@@ -1079,7 +1108,8 @@
.Lpreempt_schedule_irq:
.long preempt_schedule_irq
#endif
-.Ltrace: .long syscall_trace
+.Ltrace_entry: .long do_syscall_trace_enter
+.Ltrace_exit: .long do_syscall_trace_exit
.Lschedtail: .long schedule_tail
.Lsysc_table: .long sys_call_table
#ifdef CONFIG_TRACE_IRQFLAGS
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index fee1017..d7ce150 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -52,9 +52,9 @@
STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE = 1 << STACK_SHIFT
-_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
-_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING)
#define BASED(name) name-system_call(%r13)
@@ -310,6 +310,8 @@
jo sysc_reschedule
tm __TI_flags+7(%r9),_TIF_SIGPENDING
jnz sysc_sigpending
+ tm __TI_flags+7(%r9),_TIF_NOTIFY_RESUME
+ jnz sysc_notify_resume
tm __TI_flags+7(%r9),_TIF_RESTART_SVC
jo sysc_restart
tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
@@ -345,6 +347,14 @@
j sysc_work_loop
#
+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
+#
+sysc_notify_resume:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ larl %r14,sysc_work_loop
+ jg do_notify_resume # call do_notify_resume
+
+#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
@@ -367,20 +377,19 @@
jg do_single_step # branch to do_sigtrap
#
-# call syscall_trace before and after system call
-# special linkage: %r12 contains the return address for trace_svc
+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
+# and after the system call
#
sysc_tracesys:
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
srl %r7,2
stg %r7,SP_R2(%r15)
- brasl %r14,syscall_trace
+ brasl %r14,do_syscall_trace_enter
lghi %r0,NR_syscalls
- clg %r0,SP_R2(%r15)
+ clgr %r0,%r2
jnh sysc_tracenogo
- lg %r7,SP_R2(%r15) # strace might have changed the
- sll %r7,2 # system call
+ slag %r7,%r2,2 # *4
lgf %r8,0(%r7,%r10)
sysc_tracego:
lmg %r3,%r6,SP_R3(%r15)
@@ -391,9 +400,8 @@
tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
jz sysc_return
la %r2,SP_PTREGS(%r15) # load pt_regs
- la %r3,1
larl %r14,sysc_return # return point is sysc_return
- jg syscall_trace
+ jg do_syscall_trace_exit
#
# a new process exits the kernel with ret_from_fork
@@ -672,6 +680,8 @@
jo io_reschedule
tm __TI_flags+7(%r9),_TIF_SIGPENDING
jnz io_sigpending
+ tm __TI_flags+7(%r9),_TIF_NOTIFY_RESUME
+ jnz io_notify_resume
j io_restore
io_work_done:
@@ -712,6 +722,18 @@
TRACE_IRQS_OFF
j io_work_loop
+#
+# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
+#
+io_notify_resume:
+ TRACE_IRQS_ON
+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ brasl %r14,do_notify_resume # call do_notify_resume
+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
+ TRACE_IRQS_OFF
+ j io_work_loop
+
/*
* External interrupt handler routine
*/
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index c8b0828..1f31be1 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -35,6 +35,7 @@
#include <linux/signal.h>
#include <linux/elf.h>
#include <linux/regset.h>
+#include <linux/tracehook.h>
#include <asm/segment.h>
#include <asm/page.h>
@@ -639,40 +640,44 @@
}
#endif
-asmlinkage void
-syscall_trace(struct pt_regs *regs, int entryexit)
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
{
- if (unlikely(current->audit_context) && entryexit)
- audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), regs->gprs[2]);
-
- if (!test_thread_flag(TIF_SYSCALL_TRACE))
- goto out;
- if (!(current->ptrace & PT_PTRACED))
- goto out;
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
- ? 0x80 : 0));
+ long ret;
/*
- * If the debuffer has set an invalid system call number,
- * we prepare to skip the system call restart handling.
+ * The sysc_tracesys code in entry.S stored the system
+ * call number to gprs[2].
*/
- if (!entryexit && regs->gprs[2] >= NR_syscalls)
+ ret = regs->gprs[2];
+ if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+ (tracehook_report_syscall_entry(regs) ||
+ regs->gprs[2] >= NR_syscalls)) {
+ /*
+ * Tracing decided this syscall should not happen or the
+ * debugger stored an invalid system call number. Skip
+ * the system call and the system call restart handling.
+ */
regs->trap = -1;
-
- /*
- * this isn't the same as continuing with a signal, but it will do
- * for normal use. strace only continues with a signal if the
- * stopping signal is not SIGTRAP. -brl
- */
- if (current->exit_code) {
- send_sig(current->exit_code, current, 1);
- current->exit_code = 0;
+ ret = -1;
}
- out:
- if (unlikely(current->audit_context) && !entryexit)
- audit_syscall_entry(test_thread_flag(TIF_31BIT)?AUDIT_ARCH_S390:AUDIT_ARCH_S390X,
- regs->gprs[2], regs->orig_gpr2, regs->gprs[3],
- regs->gprs[4], regs->gprs[5]);
+
+ if (unlikely(current->audit_context))
+ audit_syscall_entry(test_thread_flag(TIF_31BIT) ?
+ AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
+ regs->gprs[2], regs->orig_gpr2,
+ regs->gprs[3], regs->gprs[4],
+ regs->gprs[5]);
+ return ret;
+}
+
+asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
+{
+ if (unlikely(current->audit_context))
+ audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
+ regs->gprs[2]);
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, 0);
}
/*
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index b976820..4f7fc30 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -24,6 +24,7 @@
#include <linux/tty.h>
#include <linux/personality.h>
#include <linux/binfmts.h>
+#include <linux/tracehook.h>
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/lowcore.h>
@@ -507,6 +508,12 @@
*/
if (current->thread.per_info.single_step)
set_thread_flag(TIF_SINGLE_STEP);
+
+ /*
+ * Let tracing know that we've done the handler setup.
+ */
+ tracehook_signal_handler(signr, &info, &ka, regs,
+ test_thread_flag(TIF_SINGLE_STEP));
}
return;
}
@@ -526,3 +533,9 @@
set_thread_flag(TIF_RESTART_SVC);
}
}
+
+void do_notify_resume(struct pt_regs *regs)
+{
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+}