linux/tools
Josh Poimboeuf 0d0970eef3 objtool: Handle another GCC stack pointer adjustment bug
The kbuild bot reported the following warning with GCC 4.4 and a
randconfig:

  net/socket.o: warning: objtool: compat_sock_ioctl()+0x1083: stack state mismatch: cfa1=7+160 cfa2=-1+0

This is caused by another GCC non-optimization, where it backs up and
restores the stack pointer for no apparent reason:

    2f91:       48 89 e0                mov    %rsp,%rax
    2f94:       4c 89 e7                mov    %r12,%rdi
    2f97:       4c 89 f6                mov    %r14,%rsi
    2f9a:       ba 20 00 00 00          mov    $0x20,%edx
    2f9f:       48 89 c4                mov    %rax,%rsp

This issue would have been happily ignored before the following commit:

  dd88a0a0c8 ("objtool: Handle GCC stack pointer adjustment bug")

But now that objtool is paying attention to such stack pointer writes
to/from a register, it needs to understand them properly.  In this case
that means recognizing that the "mov %rsp, %rax" instruction is
potentially a backup of the stack pointer.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: dd88a0a0c8 ("objtool: Handle GCC stack pointer adjustment bug")
Link: http://lkml.kernel.org/r/8c7aa8e9a36fbbb6655d9d8e7cea58958c912da8.1505942196.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-23 15:06:19 +02:00
..
accounting
arch Merge branch 'parisc-4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2017-09-05 09:37:11 -07:00
build tools build tests: Don't hardcode gcc name 2017-08-28 16:44:44 -03:00
cgroup
firewire
gpio gpio-hammer: fix make consumer_label suitable to work on gpio-nails 2017-01-26 16:29:09 +01:00
hv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-09-06 14:45:08 -07:00
iio iio: tools: add install section 2017-08-09 14:31:58 +01:00
include perf/urgent fixes: 2017-09-13 09:25:10 +02:00
kvm/kvm_stat tools/kvm_stat: add '-f help' to get the available event list 2017-07-26 19:04:53 +02:00
laptop
leds tools/leds: Add led_hw_brightness_mon program 2017-02-14 22:20:23 +01:00
lib perf/urgent fixes: 2017-09-13 09:25:10 +02:00
net tools: bpf_jit_disasm: Handle large images. 2017-06-14 15:03:22 -04:00
nfsd
objtool objtool: Handle another GCC stack pointer adjustment bug 2017-09-23 15:06:19 +02:00
pci tools: PCI: Add a missing option help line 2017-08-29 16:03:34 -05:00
pcmcia
perf mm: treewide: remove GFP_TEMPORARY allocation flag 2017-09-13 18:53:16 -07:00
power Kbuild updates for v4.14 2017-09-14 13:46:33 -07:00
scripts Kbuild updates for v4.14 2017-09-14 13:46:33 -07:00
spi spi: tools: add install section 2017-07-26 12:25:28 +01:00
testing Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-09-16 11:28:59 -07:00
thermal/tmon
time
usb usbip: auto retry for concurrent attach 2017-08-31 18:08:45 +02:00
virtio tools/virtio: fix spelling mistake: "wakeus" -> "wakeups" 2017-05-09 16:43:24 +03:00
vm tools/vm: add missing Makefile rules 2017-02-22 16:41:26 -08:00
Makefile spi: Updates for v4.14 2017-09-05 11:40:38 -07:00