linux_dsm_epyc7002/arch/s390/kernel
Vasily Gorbik b4adfe5591 s390/ftrace: save traced function caller
A typical backtrace acquired from ftraced function currently looks like
the following (e.g. for "path_openat"):

arch_stack_walk+0x15c/0x2d8
stack_trace_save+0x50/0x68
stack_trace_call+0x15a/0x3b8
ftrace_graph_caller+0x0/0x1c
0x3e0007e3c98 <- ftraced function caller (should be do_filp_open+0x7c/0xe8)
do_open_execat+0x70/0x1b8
__do_execve_file.isra.0+0x7d8/0x860
__s390x_sys_execve+0x56/0x68
system_call+0xdc/0x2d8

Note random "0x3e0007e3c98" stack value as ftraced function caller. This
value causes either imprecise unwinder result or unwinding failure.
That "0x3e0007e3c98" comes from r14 of ftraced function stack frame, which
it haven't had a chance to initialize since the very first instruction
calls ftrace code ("ftrace_caller"). (ftraced function might never
save r14 as well). Nevertheless according to s390 ABI any function
is called with stack frame allocated for it and r14 contains return
address. "ftrace_caller" itself is called with "brasl %r0,ftrace_caller".
So, to fix this issue simply always save traced function caller onto
ftraced function stack frame.

Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-12-18 23:29:26 +01:00
..
syscalls s390: wire up clone3 system call 2019-07-23 10:45:53 +02:00
vdso64 s390/vdso: fix getcpu 2019-11-30 10:52:44 +01:00
.gitignore
alternative.c
asm-offsets.c s390/vdso: fix getcpu 2019-11-30 10:52:44 +01:00
audit.c
audit.h
base.S s390/base: remove unused s390_base_mcck_handler 2019-09-03 13:53:56 +02:00
cache.c
compat_audit.c
compat_linux.c
compat_linux.h
compat_ptrace.h
compat_signal.c signal: Remove task parameter from force_sig 2019-05-27 09:36:28 -05:00
cpcmd.c
crash_dump.c memblock: memblock_phys_alloc(): don't panic 2019-03-12 10:04:01 -07:00
debug.c docs: s390: unify and update s390dbf kdocs at debug.c 2019-07-05 13:42:22 +02:00
diag.c s390/kernel: introduce .dma sections 2019-04-29 10:47:10 +02:00
dis.c s390/disassembler: don't hide instruction addresses 2019-11-12 11:24:10 +01:00
dumpstack.c s390/unwind: add stack pointer alignment sanity checks 2019-11-30 10:52:48 +01:00
early_printk.c s390/sclp: avoid using strncmp with hardcoded length 2019-08-29 15:34:58 +02:00
early.c s390: remove last diag 0x44 caller 2019-12-11 19:53:24 +01:00
ebcdic.c
entry.h PM: hibernate: powerpc: Expose pfn_is_nosave() prototype 2019-06-14 10:48:56 +02:00
entry.S s390: enforce CONFIG_SMP 2019-06-07 10:09:37 +02:00
fpu.c s390: correct some inline assembly constraints 2019-04-17 10:40:57 +02:00
ftrace.c s390/ftrace: use HAVE_FUNCTION_GRAPH_RET_ADDR_PTR 2019-05-02 13:54:11 +02:00
guarded_storage.c
head64.S s390/head64: correct init_task stack setup 2019-11-30 10:52:45 +01:00
idle.c s390/idle: fix cpu idle time calculation 2019-10-31 17:26:48 +01:00
ima_arch.c s390/kexec_file: Disable kexec_load when IPLed secure 2019-04-29 10:44:03 +02:00
ipl_vmparm.c s390/ipl: provide uapi header for list directed IPL 2019-04-26 12:34:05 +02:00
ipl.c s390/protvirt: avoid memory sharing for diag 308 set/store 2019-08-06 13:58:34 +02:00
irq.c s390/unwind: introduce stack unwind API 2019-05-02 13:54:11 +02:00
jump_label.c s390/jump_label: remove unused structure definition 2019-06-07 10:10:10 +02:00
kdebugfs.c
kexec_elf.c kexec: Fix file verification on S390 2019-09-10 13:27:51 +01:00
kexec_image.c kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE 2019-08-19 21:54:15 -07:00
kprobes.c s390/kernel: introduce .dma sections 2019-04-29 10:47:10 +02:00
lgr.c
machine_kexec_file.c Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
machine_kexec_reloc.c s390/kaslr: add support for R_390_GLOB_DAT relocation type 2019-10-22 17:55:51 +02:00
machine_kexec.c s390/kaslr: store KASLR offset for early dumps 2019-11-30 10:52:45 +01:00
Makefile s390: remove compat vdso code 2019-12-01 12:48:49 +01:00
mcount.S s390/ftrace: save traced function caller 2019-12-18 23:29:26 +01:00
module.c s390/module: avoid using strncmp with hardcoded length 2019-08-29 15:34:57 +02:00
nmi.c s390: simplify disabled_wait 2019-05-02 13:54:11 +02:00
nospec-branch.c s390 updates for the 5.2 merge window 2019-05-06 16:42:54 -07:00
nospec-sysfs.c s390: Convert IS_ENABLED uses to __is_defined 2019-04-11 13:36:53 +02:00
os_info.c
perf_cpum_cf_common.c
perf_cpum_cf_diag.c s390/cpumf: Adjust registration of s390 PMU device drivers 2019-11-20 17:16:01 +01:00
perf_cpum_cf_events.c s390/cpumf: Add extended counter set definitions for model 8561 and 8562 2019-07-11 20:40:01 +02:00
perf_cpum_cf.c s390/cpumf: Adjust registration of s390 PMU device drivers 2019-11-20 17:16:01 +01:00
perf_cpum_sf.c s390/cpum_sf: Avoid SBD overflow condition in irq handler 2019-12-11 19:53:24 +01:00
perf_event.c s390: add error handling to perf_callchain_kernel 2019-10-31 17:20:54 +01:00
perf_regs.c
pgm_check.S s390/kernel: convert SYSCALL and PGM_CHECK handlers to .quad 2019-04-29 10:47:10 +02:00
process.c s390/process: avoid custom stack unwinding in get_wchan 2019-10-31 17:20:53 +01:00
processor.c processor: get rid of cpu_relax_yield 2019-06-15 12:25:55 +02:00
ptrace.c seccomp: simplify secure_computing() 2019-10-10 14:55:24 -07:00
reipl.S s390: add missing ENDPROC statements to assembler functions 2019-05-02 13:54:11 +02:00
relocate_kernel.S s390: add missing ENDPROC statements to assembler functions 2019-05-02 13:54:11 +02:00
runtime_instr.c
setup.c s390: avoid misusing CALL_ON_STACK for task stack setup 2019-11-30 10:52:45 +01:00
signal.c signal: Remove task parameter from force_sig 2019-05-27 09:36:28 -05:00
smp.c s390: remove last diag 0x44 caller 2019-12-11 19:53:24 +01:00
stacktrace.c s390/livepatch: Implement reliable stack tracing for the consistency model 2019-11-30 10:52:48 +01:00
sthyi.c
suspend.c
swsusp.S s390: enforce CONFIG_SMP 2019-06-07 10:09:37 +02:00
sys_s390.c
sysinfo.c
time.c s390/time: remove monotonic_clock() 2019-10-31 17:20:52 +01:00
topology.c s390/topology: avoid firing events before kobjs are created 2019-09-23 23:27:52 +02:00
trace.c
traps.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2019-07-08 21:48:15 -07:00
unwind_bc.c s390/unwind: stop gracefully at user mode pt_regs in irq stack 2019-12-18 23:29:26 +01:00
uprobes.c
vdso.c s390: remove compat vdso code 2019-12-01 12:48:49 +01:00
vmlinux.lds.S vmlinux.lds.h: Replace RW_DATA_SECTION with RW_DATA 2019-11-04 15:57:41 +01:00
vtime.c sched/cputime: Rename vtime_account_system() to vtime_account_kernel() 2019-10-09 12:39:25 +02:00