sysctl: Remove the sysctl system call

This system call has been deprecated almost since it was introduced, and
in a survey of the linux distributions I can no longer find any of them
that enable CONFIG_SYSCTL_SYSCALL.  The only indication that I can find
that anyone might care is that a few of the defconfigs in the kernel
enable CONFIG_SYSCTL_SYSCALL.  However this appears in only 31 of 414
defconfigs in the kernel, so I suspect this symbols presence is simply
because it is harmless to include rather than because it is necessary.

As there appear to be no users of the sysctl system call, remove the
code.  As this removes one of the few uses of the internal kernel mount
of proc I hope this allows for even more simplifications of the proc
filesystem.

Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Anders Berg <anders.berg@lsi.com>
Cc: Apelete Seketeli <apelete@seketeli.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chee Nouk Phoon <cnphoon@altera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Christian Ruppert <christian.ruppert@abilis.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hongliang Tao <taohl@lemote.com>
Cc: Hua Yan <yanh@lemote.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Jun Nie <jun.nie@linaro.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Kevin Wells <kevin.wells@nxp.com>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Roland Stigge <stigge@antcom.de>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Scott Telford <stelford@cadence.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Tanmay Inamdar <tinamdar@apm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

arch/arc/configs/nps_defconfig

@@ -7,7 +7,6 @@ CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3=y
-CONFIG_SYSCTL_SYSCALL=y
 # CONFIG_EPOLL is not set
 # CONFIG_SIGNALFD is not set
 # CONFIG_TIMERFD is not set

arch/arc/configs/tb10x_defconfig

@@ -15,7 +15,6 @@ CONFIG_INITRAMFS_ROOT_UID=2100
 CONFIG_INITRAMFS_ROOT_GID=501
 # CONFIG_RD_GZIP is not set
 CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 # CONFIG_AIO is not set
 CONFIG_EMBEDDED=y

arch/arm/configs/axm55xx_defconfig

@@ -20,7 +20,6 @@ CONFIG_NAMESPACES=y
 CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_PROFILING=y

arch/arm/configs/keystone_defconfig

@@ -11,7 +11,6 @@ CONFIG_CGROUP_CPUACCT=y
 CONFIG_CGROUP_SCHED=y
 CONFIG_BLK_CGROUP=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 # CONFIG_ELF_CORE is not set
 # CONFIG_BASE_FULL is not set

arch/arm/configs/lpc32xx_defconfig

@@ -9,7 +9,6 @@ CONFIG_SYSFS_DEPRECATED=y
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 # CONFIG_ARCH_MULTI_V7 is not set

arch/arm/configs/moxart_defconfig

@@ -4,7 +4,6 @@ CONFIG_SYSVIPC=y
 CONFIG_NO_HZ=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
-CONFIG_SYSCTL_SYSCALL=y
 # CONFIG_ELF_CORE is not set
 # CONFIG_BASE_FULL is not set
 # CONFIG_SIGNALFD is not set

arch/arm/configs/qcom_defconfig

@@ -5,7 +5,6 @@ CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_CGROUPS=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_SLUB_DEBUG is not set

arch/arm/configs/zx_defconfig

@@ -11,7 +11,6 @@ CONFIG_RT_GROUP_SCHED=y
 CONFIG_NAMESPACES=y
 CONFIG_USER_NS=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 CONFIG_PERF_EVENTS=y

arch/m68k/configs/m5475evb_defconfig

 # CONFIG_SWAP is not set
 CONFIG_LOG_BUF_SHIFT=14
-CONFIG_SYSCTL_SYSCALL=y
 # CONFIG_KALLSYMS is not set
 # CONFIG_FUTEX is not set
 # CONFIG_EPOLL is not set

arch/mips/configs/ci20_defconfig

@@ -17,7 +17,6 @@ CONFIG_CGROUP_CPUACCT=y
 CONFIG_NAMESPACES=y
 CONFIG_USER_NS=y
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_VM_EVENT_COUNTERS is not set

arch/mips/configs/loongson3_defconfig

@@ -21,7 +21,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_SYSFS_DEPRECATED=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_MACH_LOONGSON64=y
 CONFIG_LOONGSON_MACH3X=y

arch/mips/configs/malta_qemu_32r6_defconfig

@@ -5,7 +5,6 @@ CONFIG_NO_HZ=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=15
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 CONFIG_MIPS_MALTA=y

arch/mips/configs/maltaaprp_defconfig

@@ -5,7 +5,6 @@ CONFIG_AUDIT=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=15
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 CONFIG_MIPS_MALTA=y

arch/mips/configs/maltasmvp_defconfig

@@ -5,7 +5,6 @@ CONFIG_NO_HZ=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=15
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 CONFIG_MIPS_MALTA=y

arch/mips/configs/maltasmvp_eva_defconfig

@@ -5,7 +5,6 @@ CONFIG_NO_HZ=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=15
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 CONFIG_MIPS_MALTA=y

arch/mips/configs/maltaup_defconfig

@@ -6,7 +6,6 @@ CONFIG_NO_HZ=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=15
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 CONFIG_MIPS_MALTA=y

arch/mips/configs/omega2p_defconfig

@@ -16,7 +16,6 @@ CONFIG_CGROUP_CPUACCT=y
 CONFIG_NAMESPACES=y
 CONFIG_USER_NS=y
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_VM_EVENT_COUNTERS is not set

arch/mips/configs/qi_lb60_defconfig

@@ -2,7 +2,6 @@
 CONFIG_SYSVIPC=y
 # CONFIG_CROSS_MEMORY_ATTACH is not set
 CONFIG_LOG_BUF_SHIFT=14
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_VM_EVENT_COUNTERS is not set

arch/mips/configs/vocore2_defconfig

@@ -16,7 +16,6 @@ CONFIG_CGROUP_CPUACCT=y
 CONFIG_NAMESPACES=y
 CONFIG_USER_NS=y
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_VM_EVENT_COUNTERS is not set

arch/nios2/configs/10m50_defconfig

@@ -2,7 +2,6 @@ CONFIG_SYSVIPC=y
 CONFIG_NO_HZ_IDLE=y
 CONFIG_BSD_PROCESS_ACCT=y
 CONFIG_LOG_BUF_SHIFT=14
-CONFIG_SYSCTL_SYSCALL=y
 # CONFIG_ELF_CORE is not set
 # CONFIG_EPOLL is not set
 # CONFIG_SIGNALFD is not set

arch/nios2/configs/3c120_defconfig

@@ -2,7 +2,6 @@ CONFIG_SYSVIPC=y
 CONFIG_NO_HZ_IDLE=y
 CONFIG_BSD_PROCESS_ACCT=y
 CONFIG_LOG_BUF_SHIFT=14
-CONFIG_SYSCTL_SYSCALL=y
 # CONFIG_ELF_CORE is not set
 # CONFIG_EPOLL is not set
 # CONFIG_SIGNALFD is not set

arch/parisc/configs/c8000_defconfig

@@ -9,7 +9,6 @@ CONFIG_IKCONFIG_PROC=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_SLAB=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y

arch/parisc/configs/generic-32bit_defconfig

@@ -8,7 +8,6 @@ CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=16
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_PERF_EVENTS=y
 CONFIG_SLAB=y
 CONFIG_MODULES=y

arch/powerpc/configs/40x/klondike_defconfig

@@ -4,7 +4,6 @@ CONFIG_LOG_BUF_SHIFT=14
 CONFIG_SYSFS_DEPRECATED=y
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_SLAB=y
 CONFIG_MODULES=y

arch/sh/configs/rsk7264_defconfig

@@ -8,7 +8,6 @@ CONFIG_NAMESPACES=y
 CONFIG_SYSFS_DEPRECATED=y
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 CONFIG_PERF_COUNTERS=y

arch/xtensa/configs/audio_kc705_defconfig

@@ -16,7 +16,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_PROFILING=y
 CONFIG_OPROFILE=y

arch/xtensa/configs/cadence_csp_defconfig

@@ -21,7 +21,6 @@ CONFIG_INITRAMFS_SOURCE="$$KERNEL_INITRAMFS_SOURCE"
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_PROFILING=y
 CONFIG_MODULES=y

arch/xtensa/configs/generic_kc705_defconfig

@@ -16,7 +16,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_PROFILING=y
 CONFIG_OPROFILE=y

arch/xtensa/configs/iss_defconfig

 CONFIG_SYSVIPC=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 # CONFIG_IOSCHED_DEADLINE is not set
 # CONFIG_IOSCHED_CFQ is not set
 # CONFIG_PCI is not set

arch/xtensa/configs/nommu_kc705_defconfig

@@ -21,7 +21,6 @@ CONFIG_BLK_DEV_INITRD=y
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_PERF_EVENTS=y
 CONFIG_MODULES=y

arch/xtensa/configs/smp_lx200_defconfig

@@ -16,7 +16,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_PROFILING=y
 CONFIG_OPROFILE=y

arch/xtensa/configs/virt_defconfig

@@ -15,7 +15,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_EXPERT=y
-CONFIG_SYSCTL_SYSCALL=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_PERF_EVENTS=y
 CONFIG_XTENSA_VARIANT_DC233C=y

init/Kconfig

@@ -1372,23 +1372,6 @@ config SYSFS_SYSCALL
 
 	  If unsure say Y here.
 
-config SYSCTL_SYSCALL
-	bool "Sysctl syscall support" if EXPERT
-	depends on PROC_SYSCTL
-	default n
-	select SYSCTL
-	---help---
-	  sys_sysctl uses binary paths that have been found challenging
-	  to properly maintain and use.  The interface in /proc/sys
-	  using paths with ascii names is now the primary path to this
-	  information.
-
-	  Almost nothing using the binary sysctl interface so if you are
-	  trying to save some space it is probably safe to disable this,
-	  making your kernel marginally smaller.
-
-	  If unsure say N here.
-
 config FHANDLE
 	bool "open by fhandle syscalls" if EXPERT
 	select EXPORTFS