kernel.git/arch/s390/kernel/entry.S, branch linux-2.6.28.y

[S390] fix system call parameter functions.

2008-11-27T10:06:56Z

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

[S390] ftrace: fix kernel stack backchain walking

2008-11-14T17:18:53Z

With CONFIG_IRQSOFF_TRACER the trace_hardirqs_off() function includes a call to __builtin_return_address(1). But we calltrace_hardirqs_off() from early entry code. There we have just a single stack frame. So this results in a kernel stack backchain walk that would walk beyond the kernel stack. Following the NULL terminated backchain this results in a lowcore read access. To fix this we simply call trace_hardirqs_off_caller() and pass the current instruction pointer. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

[S390] lockdep: fix compile bug

2008-11-14T17:18:53Z

arch/s390/kernel/built-in.o: In function `cleanup_io_leave_insn': mem_detect.c:(.text+0x10592): undefined reference to `lockdep_sys_exit' Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

[S390] ptrace changes

2008-10-10T19:33:57Z

* 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

[S390] s390: Optimize user and work TIF check

2008-05-07T07:23:00Z

On return from syscall or interrupt, we have to check if we return to userspace (likely) and if there is work todo (less likely) to decide if we handle the work. We can optimize this check: we first check for the less likely work case and then check for userspace. This patch is also a preparation for an additional patch, that fixes a bug in KVM dealing with cpu bound guests. Signed-off-by: Martin Schwidefsky

signals: s390: renumber TIF_RESTORE_SIGMASK

2008-04-30T15:29:37Z

TIF_RESTORE_SIGMASK no longer needs to be in the _TIF_WORK_* masks. Those low bits are scarce, and are all used up now. Renumber TIF_RESTORE_SIGMASK to free one up. Signed-off-by: Roland McGrath Cc: Oleg Nesterov Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[S390] Fix couple of section mismatches.

2008-02-05T15:50:56Z

Fix couple of section mismatches. And since we touch the code anyway change the IPL code to use C99 initializers. Cc: Michael Holzheu Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

[S390] Fix compile error on 31bit without preemption

2007-12-04T15:09:58Z

Commit b8e7a54cd06b0b0174029ef3a7f5a1415a2c28f2 introduced a compile error if CONFIG_PREEMPT is not set: arch/s390/kernel/built-in.o: In function `cleanup_io_leave_insn': /space/kvm/arch/s390/kernel/entry.S:(.text+0xbfce): undefined reference to `preempt_schedule_irq' This patch hides preempt_schedule_irq if CONFIG_PREEMPT is not set. Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky

[S390] Fix kernel preemption.

2007-11-20T10:13:46Z

When returning from IRQ handling and TIF_NEED_RESCHED is set we must call preempt_schedule_irq() instead of schedule(). Otherwise the BKL might be unlocked in schedule() and therfore everything that relies on the BKL is broken. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

[S390] Fix irq tracing and lockdep_sys_exit calls.

2007-11-20T10:13:45Z

Current support for TRACE_IRQFLAGS and lockdep_sys_exit is broken. IRQ flag tracing is broken for program checks. Even worse is that the newly introduced calls to lockdep_sys_exit are in the critical section code which is not supposed to call any C functions. In addition the checks if locks are still held are also done when returning to kernel code which is broken as well. Fix all this by disabling interrupts and machine checks at the exit paths and then do the appropriate checks and calls. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky