# git rev-parse -q --verify 65ea11ec6a82b1d44aba62b59e9eb20247e57c6e^{commit}
65ea11ec6a82b1d44aba62b59e9eb20247e57c6e
already have revision, skipping fetch
# git checkout -q -f -B kisskb 65ea11ec6a82b1d44aba62b59e9eb20247e57c6e
# git clean -qxdf
# git log -1
commit 65ea11ec6a82b1d44aba62b59e9eb20247e57c6e
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Mon Aug 8 20:35:29 2016 +0300

    x86/hweight: Don't clobber %rdi
    
    The caller expects %rdi to remain intact, push+pop it make that happen.
    
    Fixes the following kind of explosions on my core2duo machine when
    trying to reboot or shut down:
    
      general protection fault: 0000 [#1] PREEMPT SMP
      Modules linked in: i915 i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm netconsole configfs binfmt_misc iTCO_wdt psmouse pcspkr snd_hda_codec_idt e100 coretemp hwmon snd_hda_codec_generic i2c_i801 mii i2c_smbus lpc_ich mfd_core snd_hda_intel uhci_hcd snd_hda_codec snd_hwdep snd_hda_core ehci_pci 8250 ehci_hcd snd_pcm 8250_base usbcore evdev serial_core usb_common parport_pc parport snd_timer snd soundcore
      CPU: 0 PID: 3070 Comm: reboot Not tainted 4.8.0-rc1-perf-dirty #69
      Hardware name:                  /D946GZIS, BIOS TS94610J.86A.0087.2007.1107.1049 11/07/2007
      task: ffff88012a0b4080 task.stack: ffff880123850000
      RIP: 0010:[<ffffffff81003c92>]  [<ffffffff81003c92>] x86_perf_event_update+0x52/0xc0
      RSP: 0018:ffff880123853b60  EFLAGS: 00010087
      RAX: 0000000000000001 RBX: ffff88012fc0a3c0 RCX: 000000000000001e
      RDX: 0000000000000000 RSI: 0000000040000000 RDI: ffff88012b014800
      RBP: ffff880123853b88 R08: ffffffffffffffff R09: 0000000000000000
      R10: ffffea0004a012c0 R11: ffffea0004acedc0 R12: ffffffff80000001
      R13: ffff88012b0149c0 R14: ffff88012b014800 R15: 0000000000000018
      FS:  00007f8b155cd700(0000) GS:ffff88012fc00000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007f8b155f5000 CR3: 000000012a2d7000 CR4: 00000000000006f0
      Stack:
       ffff88012fc0a3c0 ffff88012b014800 0000000000000004 0000000000000001
       ffff88012fc1b750 ffff880123853bb0 ffffffff81003d59 ffff88012b014800
       ffff88012fc0a3c0 ffff88012b014800 ffff880123853bd8 ffffffff81003e13
      Call Trace:
       [<ffffffff81003d59>] x86_pmu_stop+0x59/0xd0
       [<ffffffff81003e13>] x86_pmu_del+0x43/0x140
       [<ffffffff8111705d>] event_sched_out.isra.105+0xbd/0x260
       [<ffffffff8111738d>] __perf_remove_from_context+0x2d/0xb0
       [<ffffffff8111745d>] __perf_event_exit_context+0x4d/0x70
       [<ffffffff810c8826>] generic_exec_single+0xb6/0x140
       [<ffffffff81117410>] ? __perf_remove_from_context+0xb0/0xb0
       [<ffffffff81117410>] ? __perf_remove_from_context+0xb0/0xb0
       [<ffffffff810c898f>] smp_call_function_single+0xdf/0x140
       [<ffffffff81113d27>] perf_event_exit_cpu_context+0x87/0xc0
       [<ffffffff81113d73>] perf_reboot+0x13/0x40
       [<ffffffff8107578a>] notifier_call_chain+0x4a/0x70
       [<ffffffff81075ad7>] __blocking_notifier_call_chain+0x47/0x60
       [<ffffffff81075b06>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff81076a1d>] kernel_restart_prepare+0x1d/0x40
       [<ffffffff81076ae2>] kernel_restart+0x12/0x60
       [<ffffffff81076d56>] SYSC_reboot+0xf6/0x1b0
       [<ffffffff811a823c>] ? mntput_no_expire+0x2c/0x1b0
       [<ffffffff811a83e4>] ? mntput+0x24/0x40
       [<ffffffff811894fc>] ? __fput+0x16c/0x1e0
       [<ffffffff811895ae>] ? ____fput+0xe/0x10
       [<ffffffff81072fc3>] ? task_work_run+0x83/0xa0
       [<ffffffff81001623>] ? exit_to_usermode_loop+0x53/0xc0
       [<ffffffff8100105a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
       [<ffffffff81076e6e>] SyS_reboot+0xe/0x10
       [<ffffffff814c4ba5>] entry_SYSCALL_64_fastpath+0x18/0xa3
      Code: 7c 4c 8d af c0 01 00 00 49 89 fe eb 10 48 09 c2 4c 89 e0 49 0f b1 55 00 4c 39 e0 74 35 4d 8b a6 c0 01 00 00 41 8b 8e 60 01 00 00 <0f> 33 8b 35 6e 02 8c 00 48 c1 e2 20 85 f6 7e d2 48 89 d3 89 cf
      RIP  [<ffffffff81003c92>] x86_perf_event_update+0x52/0xc0
       RSP <ffff880123853b60>
      ---[ end trace 7ec95181faf211be ]---
      note: reboot[3070] exited with preempt_count 2
    
    Cc: Borislav Petkov <bp@suse.de>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Andy Lutomirski <luto@amacapital.net>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: Denys Vlasenko <dvlasenk@redhat.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Ingo Molnar <mingo@kernel.org>
    Fixes: f5967101e9de ("x86/hweight: Get rid of the special calling convention")
    Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/um-x86_64-linux/bin/x86_64-linux-gcc --version
# < git log --format=%s --max-count=1 65ea11ec6a82b1d44aba62b59e9eb20247e57c6e
# < make -j 48 ARCH=um O=/home/kisskb/slave/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/um-x86_64-linux/bin/x86_64-linux- SUBARCH=x86_64 defconfig
kernel/time/Kconfig:155:warning: range is invalid
# make -j 48 ARCH=um O=/home/kisskb/slave/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/um-x86_64-linux/bin/x86_64-linux- SUBARCH=x86_64 
make[1]: Entering directory '/home/kisskb/slave/build/linus_um-defconfig_um-x86_64'
  GEN     ./Makefile
scripts/kconfig/conf  --silentoldconfig arch/x86/um/Kconfig
kernel/time/Kconfig:155:warning: range is invalid
  CHK     include/generated/uapi/linux/version.h
  UPD     include/generated/uapi/linux/version.h
  HOSTCC  scripts/basic/bin2c
  WRAP    arch/um/include/generated/asm/barrier.h
  WRAP    arch/um/include/generated/asm/bug.h
  WRAP    arch/um/include/generated/asm/clkdev.h
  WRAP    arch/um/include/generated/asm/cputime.h
  WRAP    arch/um/include/generated/asm/current.h
  WRAP    arch/um/include/generated/asm/device.h
  WRAP    arch/um/include/generated/asm/delay.h
  WRAP    arch/um/include/generated/asm/exec.h
  WRAP    arch/um/include/generated/asm/ftrace.h
  WRAP    arch/um/include/generated/asm/emergency-restart.h
  WRAP    arch/um/include/generated/asm/futex.h
  WRAP    arch/um/include/generated/asm/irq_regs.h
  WRAP    arch/um/include/generated/asm/hardirq.h
  WRAP    arch/um/include/generated/asm/mcs_spinlock.h
  WRAP    arch/um/include/generated/asm/hw_irq.h
  WRAP    arch/um/include/generated/asm/mutex.h
  WRAP    arch/um/include/generated/asm/irq_work.h
  WRAP    arch/um/include/generated/asm/kdebug.h
  WRAP    arch/um/include/generated/asm/param.h
  WRAP    arch/um/include/generated/asm/pci.h
  WRAP    arch/um/include/generated/asm/io.h
  WRAP    arch/um/include/generated/asm/mm-arch-hooks.h
  WRAP    arch/um/include/generated/asm/percpu.h
  WRAP    arch/um/include/generated/asm/preempt.h
  WRAP    arch/um/include/generated/asm/switch_to.h
  WRAP    arch/um/include/generated/asm/topology.h
  WRAP    arch/um/include/generated/asm/trace_clock.h
  WRAP    arch/um/include/generated/asm/word-at-a-time.h
  WRAP    arch/um/include/generated/asm/xor.h
  CHK     include/config/kernel.release
  GEN     ./Makefile
  HOSTCC  scripts/kallsyms
  CC      scripts/mod/empty.o
  HOSTCC  scripts/mod/mk_elfconfig
  CC      scripts/mod/devicetable-offsets.s
  GEN     scripts/mod/devicetable-offsets.h
  MKELF   scripts/mod/elfconfig.h
  HOSTCC  scripts/mod/modpost.o
  HOSTCC  scripts/mod/file2alias.o
  HOSTCC  scripts/mod/sumversion.o
  UPD     include/config/kernel.release
  SYSTBL  arch/x86/entry/syscalls/../../include/generated/asm/syscalls_32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/asm/unistd_32_ia32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/asm/unistd_64_x32.h
  SYSTBL  arch/x86/entry/syscalls/../../include/generated/asm/syscalls_64.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_64.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_x32.h
  HOSTLD  scripts/mod/modpost
  Using /home/kisskb/slave/src as source for kernel
  CHK     include/generated/utsrelease.h
  UPD     include/generated/utsrelease.h
  HOSTCC  scripts/unifdef
  CC      arch/x86/um/user-offsets.s
In file included from /usr/include/features.h:374:0,
                 from /usr/include/stdio.h:27,
                 from /home/kisskb/slave/src/arch/x86/um/user-offsets.c:1:
/opt/cross/gcc-4.6.3-nolibc/x86_64-linux/lib/gcc/x86_64-linux/4.6.3/../../../../x86_64-linux/include/sys/cdefs.h:385:27: fatal error: bits/wordsize.h: No such file or directory
compilation terminated.
/home/kisskb/slave/src/scripts/Makefile.build:153: recipe for target 'arch/x86/um/user-offsets.s' failed
make[2]: *** [arch/x86/um/user-offsets.s] Error 1
arch/um/Makefile:150: recipe for target 'arch/x86/um/user-offsets.s' failed
make[1]: *** [arch/x86/um/user-offsets.s] Error 2
make[1]: Leaving directory '/home/kisskb/slave/build/linus_um-defconfig_um-x86_64'
Makefile:150: recipe for target 'sub-make' failed
make: *** [sub-make] Error 2
Command 'make -j 48 ARCH=um O=/home/kisskb/slave/build/linus_um-defconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/um-x86_64-linux/bin/x86_64-linux- SUBARCH=x86_64 ' returned non-zero exit status 2
# rm -rf /home/kisskb/slave/build/linus_um-defconfig_um-x86_64
# Build took: 0:00:04.822617