# git rev-parse -q --verify daebe06ec4af252eba275f602a08086bc2bca5dc^{commit}
daebe06ec4af252eba275f602a08086bc2bca5dc
already have revision, skipping fetch
# git checkout -q -f -B kisskb daebe06ec4af252eba275f602a08086bc2bca5dc
# git clean -qxdf
# < git log -1
# commit daebe06ec4af252eba275f602a08086bc2bca5dc
# Author: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
# Date:   Wed Apr 25 16:29:31 2018 +0530
# 
#     cpufreq: powernv: Fix the hardlockup by synchronus smp_call in timer interrupt
#     
#     gpstate_timer_handler() uses synchronous smp_call to set the pstate
#     on the requested core. This causes the below hard lockup:
#     
#       smp_call_function_single+0x110/0x180 (unreliable)
#       smp_call_function_any+0x180/0x250
#       gpstate_timer_handler+0x1e8/0x580
#       call_timer_fn+0x50/0x1c0
#       expire_timers+0x138/0x1f0
#       run_timer_softirq+0x1e8/0x270
#       __do_softirq+0x158/0x3e4
#       irq_exit+0xe8/0x120
#       timer_interrupt+0x9c/0xe0
#       decrementer_common+0x114/0x120
#       -- interrupt: 901 at doorbell_global_ipi+0x34/0x50
#       LR = arch_send_call_function_ipi_mask+0x120/0x130
#       arch_send_call_function_ipi_mask+0x4c/0x130
#       smp_call_function_many+0x340/0x450
#       pmdp_invalidate+0x98/0xe0
#       change_huge_pmd+0xe0/0x270
#       change_protection_range+0xb88/0xe40
#       mprotect_fixup+0x140/0x340
#       SyS_mprotect+0x1b4/0x350
#       system_call+0x58/0x6c
#     
#     One way to avoid this is removing the smp-call. We can ensure that the
#     timer always runs on one of the policy-cpus. If the timer gets
#     migrated to a cpu outside the policy then re-queue it back on the
#     policy->cpus. This way we can get rid of the smp-call which was being
#     used to set the pstate on the policy->cpus.
#     
#     Fixes: 7bc54b652f13 ("timers, cpufreq/powernv: Initialize the gpstate timer as pinned")
#     Cc: stable@vger.kernel.org # v4.8+
#     Reported-by: Nicholas Piggin <npiggin@gmail.com>
#     Reported-by: Pridhiviraj Paidipeddi <ppaidipe@linux.vnet.ibm.com>
#     Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
#     Acked-by: Nicholas Piggin <npiggin@gmail.com>
#     Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
#     Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
# < /opt/cross/kisskb/gcc-4.6.3-nolibc/mips-linux/bin/mips-linux-gcc --version
# < git log --format=%s --max-count=1 daebe06ec4af252eba275f602a08086bc2bca5dc
# < make -s -j 40 ARCH=mips O=/kisskb/build/powerpc-fixes_mips-defconfig_mips CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/mips-linux/bin/mips-linux-  defconfig
# make -s -j 40 ARCH=mips O=/kisskb/build/powerpc-fixes_mips-defconfig_mips CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/mips-linux/bin/mips-linux-  
/kisskb/src/arch/mips/vdso/Makefile:32: MIPS VDSO requires binutils >= 2.25
/kisskb/src/arch/mips/vdso/Makefile:32: MIPS VDSO requires binutils >= 2.25
/kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount':
/kisskb/src/kernel/cgroup/cgroup-v1.c:1268:20: warning: 'root' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/rcu/srcutree.c: In function 'init_srcu_struct_fields':
/kisskb/src/kernel/rcu/srcutree.c:146:32: warning: 'levelspread[<U f00>]' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/kernel/rcu/srcutree.c:94:6: note: 'levelspread[<U f00>]' was declared here
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write':
/kisskb/src/drivers/base/regmap/regmap.c:1819:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read':
/kisskb/src/drivers/base/regmap/regmap.c:2497:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c: In function 'proc_reg_open':
/kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/fs/proc/inode.c:340:21: note: 'pdeo' was declared here
/kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq':
/kisskb/src/drivers/tty/serial/8250/8250_core.c:251:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized]
/kisskb/src/drivers/tty/serial/8250/8250_core.c:231:19: note: 'i' was declared here
/kisskb/src/arch/mips/vdso/Makefile:32: MIPS VDSO requires binutils >= 2.25
/kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl':
/kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized]
FIT description: Linux 4.17.0-rc2-gdaebe06
Created:         Thu Apr 26 20:30:21 2018
 Image 0 (kernel@0)
  Description:  Linux 4.17.0-rc2-gdaebe06
  Created:      Thu Apr 26 20:30:21 2018
  Type:         Kernel Image
  Compression:  gzip compressed
  Data Size:    4362072 Bytes = 4259.84 kB = 4.16 MB
  Architecture: MIPS
  OS:           Linux
  Load Address: 0x80100000
  Entry Point:  0x8085e1b0
  Hash algo:    sha1
  Hash value:   9a48c4802f9ee90de0c6f20453b68925f5b8fbf0
 Image 1 (fdt@boston)
  Description:  img,boston Device Tree
  Created:      Thu Apr 26 20:30:21 2018
  Type:         Flat Device Tree
  Compression:  uncompressed
  Data Size:    3668 Bytes = 3.58 kB = 0.00 MB
  Architecture: MIPS
  Hash algo:    sha1
  Hash value:   569c37cc891ce1e1f3a193cb41cc691a5d2debb5
 Image 2 (fdt@ni169445)
  Description:  NI 169445 device tree
  Created:      Thu Apr 26 20:30:21 2018
  Type:         Flat Device Tree
  Compression:  uncompressed
  Data Size:    1871 Bytes = 1.83 kB = 0.00 MB
  Architecture: MIPS
  Hash algo:    sha1
  Hash value:   51b89b31605ee62038c8468c429af091dfc75ec7
 Default Configuration: 'conf@default'
 Configuration 0 (conf@default)
  Description:  Generic Linux kernel
  Kernel:       kernel@0
 Configuration 1 (conf@boston)
  Description:  Boston Linux kernel
  Kernel:       kernel@0
  FDT:          fdt@boston
 Configuration 2 (conf@ni169445)
  Description:  NI 169445 Linux Kernel
  Kernel:       kernel@0
  FDT:          fdt@ni169445
Completed OK
# rm -rf /kisskb/build/powerpc-fixes_mips-defconfig_mips
# Build took: 0:00:57.996123