kernel/linux.git/arch/s390/lib/test_unwind.c, branch linux-7.0.y

s390: Remove superfluous newlines from inline assemblies

2025-09-29T11:52:08+00:00

Remove superfluous newlines from inline assemblies. Compilers use the number of lines of inline assemblies as heuristic for the complexity and inline decisions. Therefore inline assemblies should only contain as many lines as required. A lot of inline assemblies contain a superfluous newline for the last line. Remove such newlines to improve compiler inlining decisions. Suggested-by: Juergen Christ Signed-off-by: Heiko Carstens Reviewed-by: Alexander Gordeev Reviewed-by: Juergen Christ Signed-off-by: Alexander Gordeev

ftrace: Make ftrace_regs abstract from direct use

2024-10-11T00:18:01+00:00

ftrace_regs was created to hold registers that store information to save function parameters, return value and stack. Since it is a subset of pt_regs, it should only be used by its accessor functions. But because pt_regs can easily be taken from ftrace_regs (on most archs), it is tempting to use it directly. But when running on other architectures, it may fail to build or worse, build but crash the kernel! Instead, make struct ftrace_regs an empty structure and have the architectures define __arch_ftrace_regs and all the accessor functions will typecast to it to get to the actual fields. This will help avoid usage of ftrace_regs directly. Link: https://lore.kernel.org/all/20241007171027.629bdafd@gandalf.local.home/ Cc: "linux-arch@vger.kernel.org" Cc: "x86@kernel.org" Cc: Mathieu Desnoyers Cc: Mark Rutland Cc: Will Deacon Cc: Huacai Chen Cc: WANG Xuerui Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: Naveen N Rao Cc: Madhavan Srinivasan Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Sven Schnelle Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Link: https://lore.kernel.org/20241008230628.958778821@goodmis.org Acked-by: Catalin Marinas Signed-off-by: Steven Rostedt (Google) Acked-by: Masami Hiramatsu (Google) Acked-by: Heiko Carstens # s390 Signed-off-by: Steven Rostedt (Google)

s390/lib: Add missing MODULE_DESCRIPTION() macros

2024-06-28T12:52:30+00:00

With ARCH=s390, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in arch/s390/lib/test_kprobes_s390.o WARNING: modpost: missing MODULE_DESCRIPTION() in arch/s390/lib/test_unwind.o WARNING: modpost: missing MODULE_DESCRIPTION() in arch/s390/lib/test_modules.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Acked-by: Heiko Carstens Signed-off-by: Jeff Johnson Link: https://lore.kernel.org/r/20240615-md-s390-arch-s390-lib-v1-1-d7424b943973@quicinc.com Signed-off-by: Vasily Gorbik Signed-off-by: Alexander Gordeev

s390: Replace S390_lowcore by get_lowcore()

2024-06-18T15:01:33+00:00

Replace all S390_lowcore usages in arch/s390/ by get_lowcore(). Acked-by: Heiko Carstens Signed-off-by: Sven Schnelle Signed-off-by: Vasily Gorbik

s390/nmi: implement and use local_mcck_save() / local_mcck_restore()

2023-12-11T13:33:05+00:00

Instead of using local_mcck_disable() / local_mcck_enable() implement and use local_mcck_save() / local_mcck_restore() to disable machine checks, and restoring the previous state. The problem with using local_mcck_disable() / local_mcck_enable() is that there is an assumption that machine checks are always enabled. While this is currently the case the code still looks quite odd, readers need to double check if the code is correct. In order to increase readability save and then restore the old machine check mask bit, instead of assuming that it must have been enabled. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/kprobes: replace kretprobe with rethook

2023-01-22T17:42:35+00:00

That's an adaptation of commit f3a112c0c40d ("x86,rethook,kprobes: Replace kretprobe with rethook on x86") to s390. Replaces the kretprobe code with rethook on s390. With this patch, kretprobe on s390 uses the rethook instead of kretprobe specific trampoline code. Tested-by: Ilya Leoshkevich Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens

s390: current_stack_pointer shouldn't be a function

2022-04-12T09:56:08+00:00

s390 defines current_stack_pointer as function while all other architectures use 'register unsigned long asm(""). This make codes like the following from check_stack_object() fail: if (IS_ENABLED(CONFIG_STACK_GROWSUP)) { if ((void *)current_stack_pointer < obj + len) return BAD_STACK; } else { if (obj < (void *)current_stack_pointer) return BAD_STACK; } because this would compare the address of current_stack_pointer() and not the stackpointer value. Reported-by: Karsten Graul Fixes: 2792d84e6da5 ("usercopy: Check valid lifetime via stack depth") Cc: Kees Cook Cc: Vasily Gorbik Cc: Alexander Gordeev Signed-off-by: Sven Schnelle Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens

s390/test_unwind: verify __kretprobe_trampoline is replaced

2022-03-27T20:18:39+00:00

Reviewed-by: Tobias Huschle Signed-off-by: Vasily Gorbik

s390/test_unwind: extend kretprobe test

2022-03-27T20:18:39+00:00

Verify unwinding from kretprobed function. Reviewed-by: Tobias Huschle Signed-off-by: Vasily Gorbik

s390/test_unwind: add kretprobe tests

2022-03-10T14:58:17+00:00

Add tests to verify that s390 kretprobes maintain a correct stack chain and ensure their proper function. Reviewed-by: Vasily Gorbik Signed-off-by: Tobias Huschle Signed-off-by: Vasily Gorbik