Michael Ellerman 31278b17a0 powerpc/modules: Never restore r2 for a mprofile-kernel style mcount() call ... In the module loader we process relocations, and for long jumps we generate trampolines (aka stubs). At the call site for one of these trampolines we usually need to generate a load instruction to restore the TOC pointer into r2. There is one exception however, which is calls to mcount() using the mprofile-kernel ABI, they handle the TOC inside the stub, and so for them we do not generate a TOC load. The bug is in how the code in restore_r2() decides if it needs to generate the TOC load. It does so by looking for a nop following the branch, and if it sees a nop, it replaces it with the load. In general the compiler has no reason to generate a nop following the mcount() call and so that check works OK. However if we combine a jump label at the start of a function, with an early return, such that GCC applies the shrink-wrapping optimisation, we can then end up with an mcount call followed immediately by a nop. However the nop is not there for a TOC load, it is for the jump label. That confuses restore_r2() into replacing the jump label nop with a TOC load, which in turn confuses ftrace into replacing the mcount call with a b +8 (fixed in the previous commit). The end result is we jump over the jump label, which if it was supposed to return means we incorrectly run the body of the function. We have seen this in practice with some yet-to-be-merged patches that use jump labels more extensively. The fix is relatively simple, in restore_r2() we check for an mprofile-kernel style mcount() call first, before looking for the presence of a nop. Fixes: 153086644f ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>		2016-07-21 20:10:42 +10:00
..
vdso32	powerpc: enable UBSAN support	2016-01-20 17:09:18 -08:00
vdso64	powerpc: enable UBSAN support	2016-01-20 17:09:18 -08:00
.gitignore
align.c	powerpc: Send SIGBUS on unaligned copy and paste	2016-07-05 23:49:51 +10:00
asm-offsets.c	powerpc/asm: Remove unused symbols in asm-offsets.c	2016-06-16 15:11:25 +10:00
audit.c
btext.c	powerpc/mm: Use a helper for finding pte bits mapping I/O area	2016-05-01 18:32:32 +10:00
cacheinfo.c
cacheinfo.h
compat_audit.c
cpu_setup_6xx.S	powerpc: Various typo fixes	2016-06-14 13:58:26 +10:00
cpu_setup_44x.S
cpu_setup_fsl_booke.S	powerpc/cache: add cache flush operation for various e500	2016-03-04 23:44:51 -06:00
cpu_setup_pa6t.S
cpu_setup_power.S	powerpc/irq: Add support for HV virtualization interrupts	2016-07-17 16:42:44 +10:00
cpu_setup_ppc970.S
cputable.c	powerpc/mm: Clear top 16 bits of va only on older cpus	2016-07-17 16:42:52 +10:00
crash.c	powerpc/crash: Rearrange loop condition to avoid out of bounds array access	2016-07-14 20:26:22 +10:00
crash_dump.c
dbell.c
dma-iommu.c
dma-swiotlb.c
dma.c	powerpc/dma: dma_set_coherent_mask() should not be GPL only	2015-10-28 14:20:50 +09:00
eeh.c	Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell"	2016-05-12 19:52:21 +10:00
eeh_cache.c	powerpc/eeh: Fix pr_debug()s in eeh_cache.c	2016-07-08 22:09:50 +10:00
eeh_dev.c	powerpc/pci: Delay populating pdn	2016-06-21 15:30:56 +10:00
eeh_driver.c	powerpc fixes for 4.7 #5	2016-07-15 14:57:47 +10:00
eeh_event.c	powerpc: sparse: static-ify some things	2016-04-12 21:05:18 +10:00
eeh_pe.c	powerpc/eeh: fix misleading indentation	2016-04-27 09:19:37 +10:00
eeh_sysfs.c
entry_32.S
entry_64.S	powerpc: Define and use PPC64_ELF_ABI_v2/v1	2016-06-14 13:58:27 +10:00
epapr_hcalls.S
epapr_paravirt.c
exceptions-64e.S	powerpc: Various typo fixes	2016-06-14 13:58:26 +10:00
exceptions-64s.S	powerpc/irq: Add support for HV virtualization interrupts	2016-07-17 16:42:44 +10:00
fadump.c	powerpc/fadump: Fix build error introduced by recent cleanup	2016-07-05 23:49:46 +10:00
firmware.c
fpu.S	powerpc: Add the ability to save FPU without giving it up	2016-03-02 23:34:49 +11:00
fsl_booke_entry_mapping.S
ftrace.c	powerpc/ftrace: Separate the heuristics for checking call sites	2016-07-21 20:10:37 +10:00
head_8xx.S	powerpc/8xx: rewrite set_context() in C	2016-03-11 17:20:11 -06:00
head_32.S
head_40x.S
head_44x.S	powerpc: Fix misspellings in comments.	2016-03-01 19:27:20 +11:00
head_64.S	powerpc/64: Move the content of setup_system() to setup_arch()	2016-07-21 19:14:29 +10:00
head_booke.h
head_fsl_booke.S	powerpc/cache: add cache flush operation for various e500	2016-03-04 23:44:51 -06:00
hw_breakpoint.c	powerpc/hw_breakpoint: Fix oops when destroying hw_breakpoint event	2016-03-03 22:06:08 +11:00
ibmebus.c	powerpc: sparse: static-ify some things	2016-04-12 21:05:18 +10:00
idle.c
idle_6xx.S
idle_book3e.S
idle_book3s.S	powerpc/opal: Add real mode call wrappers	2016-07-17 16:42:46 +10:00
idle_e500.S
idle_power4.S
io-workarounds.c	powerpc/mm: Differentiate between hugetlb and THP during page walk	2015-10-12 15:30:09 +11:00
io.c
iomap.c
iommu.c
irq.c	powerpc/irq: Add mechanism to force a replay of interrupts	2016-07-17 16:42:44 +10:00
isa-bridge.c	powerpc/mm: Use a helper for finding pte bits mapping I/O area	2016-05-01 18:32:32 +10:00
jump_label.c
kgdb.c	powerpc: Fix kgdb on little endian ppc64le	2016-02-18 00:03:26 +11:00
kprobes.c	powerpc/kprobes: Remove kretprobe_trampoline_holder.	2016-06-21 15:30:49 +10:00
kvm.c
kvm_emul.S
l2cr_6xx.S
legacy_serial.c
machine_kexec.c	powerpc: Update of_remove_property() call sites to remove null checking	2016-05-11 21:54:04 +10:00
machine_kexec_32.c
machine_kexec_64.c	powerpc/mm: Move hash table ops to a separate structure	2016-07-21 18:59:09 +10:00
Makefile	powerpc/32: Remove RELOCATABLE_PPC32	2016-07-19 20:17:07 +10:00
mce.c	powerpc updates for 4.7	2016-05-20 10:12:41 -07:00
mce_power.c	powerpc/mm/radix: Fix CONFIG_PPC_MMU_STD_64 typo	2016-05-11 21:53:59 +10:00
misc.S
misc_32.S	powerpc/32: Get rid of sub_reloc_offset()	2016-06-14 13:58:26 +10:00
misc_64.S	powerpc/mm: Move hash table ops to a separate structure	2016-07-21 18:59:09 +10:00
module.c	powerpc/module: Only try to generate the ftrace_caller() stub once	2016-03-07 14:53:53 +11:00
module_32.c	powerpc/module: Only try to generate the ftrace_caller() stub once	2016-03-07 14:53:53 +11:00
module_64.c	powerpc/modules: Never restore r2 for a mprofile-kernel style mcount() call	2016-07-21 20:10:42 +10:00
msi.c
nvram_64.c	powerpc: make kernel/nvram_64.c explicitly non-modular	2016-04-11 20:30:43 +10:00
of_platform.c
paca.c	powerpc: Create a helper for getting the kernel toc value	2016-03-07 14:53:52 +11:00
pci-common.c	powerpc/pci: Don't try to allocate resources that will be reassigned	2016-07-17 16:42:49 +10:00
pci-hotplug.c	powerpc/pci: Don't scan empty slot	2016-05-11 21:54:26 +10:00
pci_32.c
pci_64.c	powerpc fixes for 4.7 #5	2016-07-15 14:57:47 +10:00
pci_dn.c	powerpc/pci: Fix build with PCI_IOV=y and EEH=n	2016-07-07 16:33:27 +10:00
pci_of_scan.c	PCI/MSI: Initialize MSI capability for all architectures	2015-11-24 17:45:18 -06:00
pmc.c
ppc32.h
ppc_ksyms.c	powerpc32: move xxxxx_dcache_range() functions inline	2016-03-11 17:20:12 -06:00
ppc_ksyms_32.c	powerpc32: Remove clear_pages() and define clear_page() inline	2016-03-11 17:20:11 -06:00
ppc_save_regs.S
proc_powerpc.c
process.c	powerpc fixes for 4.7 #5	2016-07-15 14:57:47 +10:00
prom.c	powerpc/64: Move MMU backend selection out of platform code	2016-07-21 18:56:38 +10:00
prom_init.c	powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added	2016-06-08 10:40:05 +10:00
prom_init_check.sh
prom_parse.c
ptrace.c	powerpc/ptrace: Fix out of bounds array access warning	2016-06-06 10:48:07 +10:00
ptrace32.c
reloc_32.S
reloc_64.S
rtas-proc.c	powerpc: Various typo fixes	2016-06-14 13:58:26 +10:00
rtas-rtc.c
rtas.c	powerpc: Make ppc_md.{halt, restart} __noreturn	2016-07-14 21:12:06 +10:00
rtas_flash.c
rtas_pci.c
rtasd.c	powerpc/pseries: start rtasd before PCI probing	2016-07-08 19:22:15 +10:00
setup-common.c	powerpc: Merge 32-bit and 64-bit setup_arch()	2016-07-21 19:17:46 +10:00
setup.h	powerpc: Merge 32-bit and 64-bit setup_arch()	2016-07-21 19:17:46 +10:00
setup_32.c	powerpc: Merge 32-bit and 64-bit setup_arch()	2016-07-21 19:17:46 +10:00
setup_64.c	powerpc: Merge 32-bit and 64-bit setup_arch()	2016-07-21 19:17:46 +10:00
signal.c	powerpc: Fix misspellings in comments.	2016-03-01 19:27:20 +11:00
signal.h	powerpc: Fix misspellings in comments.	2016-03-01 19:27:20 +11:00
signal_32.c	powerpc fixes for 4.4 #2	2015-12-14 20:40:32 +11:00
signal_64.c	powerpc: Avoid load hit store in setup_sigcontext()	2016-06-14 13:58:25 +10:00
smp-tbsync.c
smp.c	powerpc: export cpu_to_core_id()	2016-06-21 15:30:51 +10:00
stacktrace.c	powerpc: Implement save_stack_trace_regs() to enable kprobe stack tracing	2016-01-11 14:27:28 +11:00
suspend.c
swsusp.c	powerpc/mm: Abstraction for switch_mmu_context()	2016-05-01 18:33:04 +10:00
swsusp_32.S
swsusp_64.c
swsusp_asm64.S
swsusp_booke.S
sys_ppc32.c
syscalls.c
sysfs.c	powerpc/sparse: make some things static	2016-06-16 22:23:11 +10:00
systbl.S
systbl_chk.c	powerpc: Standardise on NR_syscalls rather than __NR_syscalls.	2015-11-26 22:11:17 +11:00
systbl_chk.sh	powerpc: Standardise on NR_syscalls rather than __NR_syscalls.	2015-11-26 22:11:17 +11:00
tau_6xx.c
time.c	powerpc/timer: Large Decrementer support	2016-07-05 23:58:53 +10:00
tm.S	powerpc/tm: Fix stack pointer corruption in __tm_recheckpoint()	2016-07-15 15:00:18 +10:00
trace_clock.c
traps.c	powerpc: Load Monitor Register Support	2016-06-21 15:30:50 +10:00
udbg.c
udbg_16550.c
uprobes.c
vdso.c	vdso: make arch_setup_additional_pages wait for mmap_sem for write killable	2016-05-23 17:04:14 -07:00
vecemu.c
vector.S	powerpc: Add the ability to save VSX without giving it up	2016-03-02 23:34:50 +11:00
vio.c	powerpc: sparse: static-ify some things	2016-04-12 21:05:18 +10:00
vmlinux.lds.S	powerpc/32: Remove RELOCATABLE_PPC32	2016-07-19 20:17:07 +10:00