linux/arch/x86/kernel
Josh Poimboeuf 6f727b84e2 x86/dumpstack/ftrace: Mark function graph handler function as unreliable
When function graph tracing is enabled for a function, its return
address on the stack is replaced with the address of an ftrace handler
(return_to_handler).

Currently 'return_to_handler' can be reported as reliable.  That's not
ideal, and can actually be misleading.  When saving or dumping the
stack, you normally only care about what led up to that point (the call
path), rather than what will happen in the future (the return path).

That's especially true in the non-oops stack trace case, which isn't
used for debugging.  For example, in a perf profiling operation,
reporting return_to_handler() in the trace would just be confusing.

And in the oops case, where debugging is important, "unreliable" is also
more appropriate there because it serves as a hint that graph tracing
was involved, instead of trying to imply that return_to_handler() was
the real caller.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f8af15749c7d632d3e7f815995831d5b7f82950d.1471607358.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-24 12:15:15 +02:00
..
acpi x86/asm/head: Rename 'stack_start' -> 'initial_stack' 2016-08-18 18:41:29 +02:00
apic Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-12 14:31:10 -07:00
cpu x86/entry: Remove outdated comment about SYSCALL targets 2016-08-24 11:20:31 +02:00
fpu x86/mm/pkeys: Fix compact mode by removing protection keys' XSAVE buffer manipulation 2016-08-10 16:12:26 +02:00
kprobes kprobes/x86: Clear TF bit in fault on single-stepping 2016-06-14 12:00:54 +02:00
.gitignore
alternative.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
amd_gart_64.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
amd_nb.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
apb_timer.c x86/apb_timer: Convert to hotplug state machine 2016-07-15 10:40:22 +02:00
aperture_64.c param: convert some "on"/"off" users to strtobool 2016-03-17 15:09:34 -07:00
apm_32.c x86/apm32: Remove paravirt_enabled() use 2016-04-22 10:29:03 +02:00
asm-offsets_32.c x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup 2016-03-10 09:48:14 +01:00
asm-offsets_64.c x86/syscalls: Add syscall entry qualifiers 2016-01-29 09:46:38 +01:00
asm-offsets.c x86/uaccess: Move thread_info::addr_limit to thread_struct 2016-07-15 10:26:30 +02:00
audit_64.c
bootflag.c
check.c Linux 4.2-rc8 2015-08-25 09:59:19 +02:00
cpuid.c new helpers: no_seek_end_llseek{,_size}() 2015-12-23 10:41:31 -05:00
crash_dump_32.c
crash_dump_64.c
crash.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
devicetree.c x86/cpufeature: Replace cpu_has_apic with boot_cpu_has() usage 2016-04-13 11:37:41 +02:00
doublefault.c
dumpstack_32.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
dumpstack_64.c x86/dumpstack: Remove 64-byte gap at end of irq stack 2016-08-18 18:41:33 +02:00
dumpstack.c x86/dumpstack/ftrace: Mark function graph handler function as unreliable 2016-08-24 12:15:15 +02:00
e820.c Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 09:32:27 -07:00
early_printk.c x86: Fix misspellings in comments 2016-02-24 08:44:58 +01:00
early-quirks.c Linux 4.7 2016-07-26 17:26:29 +10:00
ebda.c x86/boot: Simplify EBDA-vs-BIOS reservation logic 2016-07-22 11:46:01 +02:00
espfix_64.c x86: get rid of superfluous __GFP_REPEAT 2016-06-24 17:23:52 -07:00
ftrace.c ftrace/x86: Implement HAVE_FUNCTION_GRAPH_RET_ADDR_PTR 2016-08-24 12:15:15 +02:00
head32.c x86/boot: Run reserve_bios_regions() after we initialize the memory map 2016-08-11 11:14:59 +02:00
head64.c x86/boot: Run reserve_bios_regions() after we initialize the memory map 2016-08-11 11:14:59 +02:00
head_32.S x86/asm/head: Rename 'stack_start' -> 'initial_stack' 2016-08-18 18:41:29 +02:00
head_64.S x86/head: Remove useless zeroed word 2016-08-18 18:41:30 +02:00
hpet.c x86/hpet: Fix /dev/rtc breakage caused by RTC cleanup 2016-08-10 14:37:06 +02:00
hw_breakpoint.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
i386_ksyms_32.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
i8237.c
i8253.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
i8259.c x86/irq: Probe for PIC presence before allocating descs for legacy IRQs 2015-11-07 10:37:37 +01:00
io_delay.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
ioport.c x86/iopl: Fix iopl capability check on Xen PV 2016-03-17 09:49:27 +01:00
irq_32.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
irq_64.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
irq_work.c treewide: Remove old email address 2015-11-23 09:44:58 +01:00
irq.c x86/irq: Do not substract irq_tlb_count from irq_call_count 2016-08-11 11:14:59 +02:00
irqinit.c x86/irq: Store irq descriptor in vector array 2015-08-06 00:14:59 +02:00
jump_label.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
kdebugfs.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
kexec-bzimage64.c KEYS: Generalise system_verify_data() to provide access to internal content 2016-04-06 16:14:24 +01:00
kgdb.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
ksysfs.c
kvm.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
kvmclock.c x86: Fix misspellings in comments 2016-02-24 08:44:58 +01:00
ldt.c x86/mm: Factor out LDT init from context init 2016-02-18 19:46:31 +01:00
machine_kexec_32.c
machine_kexec_64.c kexec: provide arch_kexec_protect(unprotect)_crashkres() 2016-05-23 17:04:14 -07:00
Makefile Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching 2016-05-17 17:11:27 -07:00
mcount_64.S ftrace/x86: Set ftrace_stub to weak to prevent gcc from using short jumps to it 2016-05-20 13:28:40 -04:00
mmconf-fam10h_64.c
module.c x86/asm: Stop depending on ptrace.h in alternative.h 2016-04-29 11:56:40 +02:00
mpparse.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
msr.c x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
nmi_selftest.c
nmi.c x86: include linux/ratelimit.h in nmi.c 2016-06-06 17:10:15 +02:00
paravirt_patch_32.c x86/paravirt: Remove the unused irq_enable_sysexit pv op 2015-11-23 10:48:16 +01:00
paravirt_patch_64.c x86/entry, x86/paravirt: Remove the unused usergs_sysret32 PV op 2015-11-23 10:48:16 +01:00
paravirt-spinlocks.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
paravirt.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
pci-calgary_64.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pci-dma.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pci-iommu_table.c x86: Fix non-static inlines 2016-04-16 13:21:40 +02:00
pci-nommu.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pci-swiotlb.c dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
pcspeaker.c
perf_regs.c
platform-quirks.c x86/boot: Reorganize and clean up the BIOS area reservation code 2016-07-21 10:11:57 +02:00
pmem.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
probe_roms.c
process_32.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
process_64.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
process.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
ptrace.c x86/dumpstack: Fix x86_32 kernel_stack_pointer() previous stack access 2016-08-18 18:41:31 +02:00
pvclock.c pvclock: introduce seqcount-like API 2016-08-04 13:52:21 +02:00
quirks.c timers/x86/hpet: Type adjustments 2015-10-21 11:17:32 +02:00
reboot_fixups_32.c
reboot.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
relocate_kernel_32.S
relocate_kernel_64.S
resource.c
rtc.c char/genrtc: x86: remove remnants of asm/rtc.h 2016-06-04 00:20:07 +02:00
setup_percpu.c x86/dumpstack: Remove 64-byte gap at end of irq stack 2016-08-18 18:41:33 +02:00
setup.c x86/boot: Defer setup_real_mode() to early_initcall time 2016-08-11 11:15:00 +02:00
signal_compat.c x86/signals: Add build-time checks to the siginfo compat code 2016-06-14 12:19:24 +02:00
signal.c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-06 09:04:35 -04:00
smp.c x86/smp: Remove single IPI wrapper 2015-11-05 13:07:54 +01:00
smpboot.c x86/asm/head: Rename 'stack_start' -> 'initial_stack' 2016-08-18 18:41:29 +02:00
stacktrace.c x86/kernel: Audit and remove any unnecessary uses of module.h 2016-07-14 15:06:41 +02:00
step.c Merge branch 'x86/urgent' into x86/asm to fix up conflicts and to pick up fixes 2015-08-18 09:39:47 +02:00
sys_x86_64.c
sysfb_efi.c Merge branch 'linus' into efi/core, to pick up fixes 2016-05-07 07:00:07 +02:00
sysfb_simplefb.c
sysfb.c
tboot.c x86/tboot: Convert to hotplug state machine 2016-07-15 10:40:30 +02:00
tce_64.c x86/cpufeature: Remove cpu_has_clflush 2016-03-31 13:35:09 +02:00
test_nx.c x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option 2016-02-22 08:51:38 +01:00
test_rodata.c x86: Don't use module.h just for AUTHOR / LICENSE tags 2016-07-14 13:04:20 +02:00
time.c
tls.c x86/tls: Synchronize segment registers in set_thread_area() 2016-04-29 11:56:42 +02:00
tls.h
topology.c
trace_clock.c
tracepoint.c
traps.c x86/mm/64: Enable vmapped stacks (CONFIG_HAVE_ARCH_VMAP_STACK=y) 2016-08-24 12:11:42 +02:00
tsc_msr.c x86/tsc_msr: Remove irqoff around MSR-based TSC enumeration 2016-07-11 21:30:12 +02:00
tsc_sync.c
tsc.c Merge branch 'linus' into timers/urgent, to pick up fixes 2016-08-10 14:36:23 +02:00
uprobes.c uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions 2016-08-12 08:29:24 +02:00
verify_cpu.S x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
vm86_32.c x86, bitops: remove use of "sbb" to return CF 2016-06-08 12:41:20 -07:00
vmlinux.lds.S x86/boot: Move compressed kernel to the end of the decompression buffer 2016-04-29 11:03:29 +02:00
vsmp_64.c
x86_init.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00
x8664_ksyms_64.c Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-08-01 14:23:42 -04:00