linux/arch
Hendrik Brueckner bc3703f21c s390/kernel: emit CFI data in .debug_frame and discard .eh_frame sections
Using perf probe and libdw on kernel modules failed to find CFI
data for symbols.  The CFI data is stored in the .eh_frame section.
The elfutils libdw is not able to extract the CFI data correctly,
because the .eh_frame section requires "non-simple" relocations
for kernel modules.

The suggestion is to avoid these "non-simple" relocations by emitting
the CFI data in the .debug_frame section.  Let gcc emit respective
directives by specifying the -fno-asynchronous-unwind-tables option.

Using the .debug_frame section for CFI data, the .eh_frame section
becomes unused and, thus, discard it for kernel and modules builds

The vDSO requires the .eh_frame section and, hence, emit the CFI data
in both, the .eh_frame and .debug_frame sections.

See also discussion on elfutils/libdw bugzilla:
https://sourceware.org/bugzilla/show_bug.cgi?id=22452

Suggested-by: Mark Wielaard <mark@klomp.org>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-12-13 10:51:35 +01:00
..
alpha bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
arc bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
arm ARM: SoC fixes for 4.15-rc 2017-12-10 08:26:59 -08:00
arm64 ARM: SoC fixes for 4.15-rc 2017-12-10 08:26:59 -08:00
blackfin bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
c6x bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
cris bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
frv bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
h8300 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
hexagon bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
ia64 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
m32r bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
m68k Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-12-08 13:32:44 -08:00
metag bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
microblaze bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
mips Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-12-08 13:32:44 -08:00
mn10300 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
nios2 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
openrisc bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
parisc bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
powerpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-12-08 13:32:44 -08:00
riscv bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
s390 s390/kernel: emit CFI data in .debug_frame and discard .eh_frame sections 2017-12-13 10:51:35 +01:00
score bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
sh bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
sparc bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
tile bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
um This pull request contains the following core changes: 2017-11-22 20:46:06 -10:00
unicore32 bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
x86 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-12-11 16:32:45 -08:00
xtensa bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type 2017-12-05 15:02:40 +01:00
.gitignore
Kconfig bpf: Revert bpf_overrid_function() helper changes. 2017-11-11 18:24:55 +09:00