Vasily Gorbik 45f7a0da60 s390/ftrace: generate traced function stack frame ... Currently backtrace from ftraced function does not contain ftraced function itself. e.g. for "path_openat": arch_stack_walk+0x15c/0x2d8 stack_trace_save+0x50/0x68 stack_trace_call+0x15e/0x3d8 ftrace_graph_caller+0x0/0x1c <-- ftrace code do_filp_open+0x7c/0xe8 <-- ftraced function caller do_open_execat+0x76/0x1b8 open_exec+0x52/0x78 load_elf_binary+0x180/0x1160 search_binary_handler+0x8e/0x288 load_script+0x2a8/0x2b8 search_binary_handler+0x8e/0x288 __do_execve_file.isra.39+0x6fa/0xb40 __s390x_sys_execve+0x56/0x68 system_call+0xdc/0x2d8 Ftraced function is expected in the backtrace by ftrace kselftests, which are now failing. It would also be nice to have it for clarity reasons. "ftrace_caller" itself is called without stack frame allocated for it and does not store its caller (ftraced function). Instead it simply allocates a stack frame for "ftrace_trace_function" and sets backchain to point to ftraced function stack frame (which contains ftraced function caller in saved r14). To fix this issue make "ftrace_caller" allocate a stack frame for itself just to store ftraced function for the stack unwinder. As a result backtrace looks like the following: arch_stack_walk+0x15c/0x2d8 stack_trace_save+0x50/0x68 stack_trace_call+0x15e/0x3d8 ftrace_graph_caller+0x0/0x1c <-- ftrace code path_openat+0x6/0xd60 <-- ftraced function do_filp_open+0x7c/0xe8 <-- ftraced function caller do_open_execat+0x76/0x1b8 open_exec+0x52/0x78 load_elf_binary+0x180/0x1160 search_binary_handler+0x8e/0x288 load_script+0x2a8/0x2b8 search_binary_handler+0x8e/0x288 __do_execve_file.isra.39+0x6fa/0xb40 __s390x_sys_execve+0x56/0x68 system_call+0xdc/0x2d8 Reported-by: Sven Schnelle <sven.schnelle@ibm.com> Tested-by: Sven Schnelle <sven.schnelle@ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>		2020-01-22 13:05:35 +01:00
..
appldata	proc/sysctl: add shared variables for range check	2019-07-18 17:08:07 -07:00
boot	s390/kaslr: store KASLR offset for early dumps	2019-11-30 10:52:45 +01:00
configs	locking/refcount: Consolidate implementations of refcount_t	2019-11-25 09:15:32 +01:00
crypto	Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2019-11-25 19:49:58 -08:00
hypfs	Merge branch 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-09-24 12:33:34 -07:00
include	s390/jump_label: use "i" constraint for clang	2020-01-22 13:05:35 +01:00
kernel	s390/ftrace: generate traced function stack frame	2020-01-22 13:05:35 +01:00
kvm	KVM: s390: small fixes and enhancements	2019-11-18 13:16:46 +01:00
lib	s390/test_unwind: fix spelling mistake "reqister" -> "register"	2019-12-11 19:53:23 +01:00
mm	s390/kasan: add KASAN_VMALLOC support	2019-12-11 19:56:59 +01:00
net	s390/bpf: Remove JITed image size limitations	2019-11-18 19:51:16 -08:00
numa	s390/numa: correct early_param handling	2019-08-26 12:51:17 +02:00
oprofile
pci	s390/pci: Fix possible deadlock in recover_store()	2020-01-22 13:05:34 +01:00
purgatory	crypto: sha256 - Merge crypto/sha256.h into crypto/sha.h	2019-09-05 14:54:54 +10:00
scripts	s390/build: use size command to perform empty .bss check	2019-08-08 14:36:53 +02:00
tools	s390: add support for IBM z15 machines	2019-09-13 12:19:14 +02:00
Kbuild
Kconfig	s390/kasan: add KASAN_VMALLOC support	2019-12-11 19:56:59 +01:00
Kconfig.debug
Makefile	s390: adjust -mpacked-stack support check for clang 10	2020-01-22 13:05:35 +01:00