user/sven/linux.git/arch/s390/kernel/dumpstack.c, branch v5.7

sched/rt, s390: Use CONFIG_PREEMPTION

2019-12-08T13:37:35Z

CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the preemption and entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT output to die(). [bigeasy: +Kconfig, dumpstack.c] Signed-off-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Cc: Christian Borntraeger Cc: Heiko Carstens Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Vasily Gorbik Cc: linux-s390@vger.kernel.org Link: https://lore.kernel.org/r/20191015191821.11479-18-bigeasy@linutronix.de Signed-off-by: Ingo Molnar

s390/unwind: add stack pointer alignment sanity checks

2019-11-30T09:52:48Z

ABI requires SP to be aligned 8 bytes, report unwinding error otherwise. Link: https://lkml.kernel.org/r/20191106095601.29986-5-mbenes@suse.cz Reviewed-by: Heiko Carstens Tested-by: Miroslav Benes Signed-off-by: Miroslav Benes Signed-off-by: Vasily Gorbik

s390/test_unwind: print verbose unwinding results

2019-11-30T09:52:48Z

Add stack name, sp and reliable information into test unwinding results. Also consider ip outside of kernel text as failure if the state is reported reliable. Acked-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/unwind: unify task is current checks

2019-11-30T09:52:45Z

Avoid mixture of task == NULL and task == current meaning the same thing and simply always initialize task with current in unwind_start. Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/unwind: remove stack recursion warning

2019-08-06T11:58:35Z

Remove pointless stack recursion on stack type ... warning, which only confuses people. There is no way to make backchain unwinder 100% reliable. When a task is interrupted in-between stack frame allocation and backchain write instructions new stack frame backchain pointer is left uninitialized (there are also sometimes additional instruction in-between stack frame allocation and backchain write instructions due to gcc shrink-wrapping). In attempt to unwind such stack the unwinder would still try to use that invalid backchain value and perform all kind of sanity checks on it to make sure we are not pointed out of stack. In some cases that invalid backchain value would be 0 and we would falsely treat next stackframe as pt_regs and again gprs[15] in those pt_regs might happen to point at some address within the task's stack. Acked-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390: enforce CONFIG_SMP

2019-06-07T08:09:37Z

There never have been distributions that shiped with CONFIG_SMP=n for s390. In addition the kernel currently doesn't even compile with CONFIG_SMP=n for s390. Most likely it wouldn't even work, even if we fix the compile error, since nobody tests it, since there is no use case that I can think of. Therefore simply enforce CONFIG_SMP and get rid of some more or less unused code. Reviewed-by: Christian Borntraeger Signed-off-by: Heiko Carstens

s390/unwind: introduce stack unwind API

2019-05-02T11:54:11Z

Rework the dump_trace() stack unwinder interface to support different unwinding algorithms. The new interface looks like this: struct unwind_state state; unwind_for_each_frame(&state, task, regs, start_stack) do_something(state.sp, state.ip, state.reliable); The unwind_bc.c file contains the implementation for the classic back-chain unwinder. One positive side effect of the new code is it now handles ftraced functions gracefully. It prints the real name of the return function instead of 'return_to_handler'. Signed-off-by: Martin Schwidefsky

s390/dumpstack: print psw mask and address again

2018-10-10T05:37:20Z

With pointer obfuscation the output of show_registers() became quite useless: Krnl PSW : (____ptrval____) (____ptrval____) (__list_add_valid+0x98/0xa8) In order to print the psw mask and address use %px instead of %p. And the output looks again like this: Krnl PSW : 0404d00180000000 00000000007c0dd0 (__list_add_valid+0x98/0xa8) Reviewed-by: Martin Schwidefsky Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/dumpstack: disable __dump_trace kasan instrumentation

2018-10-09T09:21:27Z

Walking async_stack produces false positives. Disable __dump_trace function instrumentation for now. Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390: unify stack size definitions

2018-10-09T09:20:58Z

Remove STACK_ORDER and STACK_SIZE in favour of identical THREAD_SIZE_ORDER and THREAD_SIZE definitions. THREAD_SIZE and THREAD_SIZE_ORDER naming is misleading since it is used as general kernel stack size information. But both those definitions are used in the common code and throughout architectures specific code, so changing the naming is problematic. Reviewed-by: Martin Schwidefsky Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky