From 59da21398e680e8100625d689c8bebee6a139e93 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Thu, 27 Nov 2008 11:05:55 +0100 Subject: [S390] fix system call parameter functions. syscall_get_nr() currently returns a valid result only if the call chain of the traced process includes do_syscall_trace_enter(). But collect_syscall() can be called for any sleeping task, the result of syscall_get_nr() in general is completely bogus. To make syscall_get_nr() work for any sleeping task the traps field in pt_regs is replace with svcnr - the system call number the process is executing. If svcnr == 0 the process is not on a system call path. The syscall_get_arguments and syscall_set_arguments use regs->gprs[2] for the first system call parameter. This is incorrect since gprs[2] may have been overwritten with the system call number if the call chain includes do_syscall_trace_enter. Use regs->orig_gprs2 instead. Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/signal.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/s390/kernel/signal.c') diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c index 4f7fc3059a8e..8e6812a22670 100644 --- a/arch/s390/kernel/signal.c +++ b/arch/s390/kernel/signal.c @@ -160,7 +160,7 @@ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs) current->thread.fp_regs.fpc &= FPC_VALID_MASK; restore_fp_regs(¤t->thread.fp_regs); - regs->trap = -1; /* disable syscall checks */ + regs->svcnr = 0; /* disable syscall checks */ return 0; } @@ -445,7 +445,7 @@ void do_signal(struct pt_regs *regs) oldset = ¤t->blocked; /* Are we from a system call? */ - if (regs->trap == __LC_SVC_OLD_PSW) { + if (regs->svcnr) { continue_addr = regs->psw.addr; restart_addr = continue_addr - regs->ilc; retval = regs->gprs[2]; @@ -462,7 +462,7 @@ void do_signal(struct pt_regs *regs) case -ERESTART_RESTARTBLOCK: regs->gprs[2] = -EINTR; } - regs->trap = -1; /* Don't deal with this again. */ + regs->svcnr = 0; /* Don't deal with this again. */ } /* Get signal to deliver. When running under ptrace, at this point -- cgit v1.2.3