Merge tag 'tiny/for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux

Pull "tinification" patches from Josh Triplett.

Work on making smaller kernels.

* tag 'tiny/for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux:
  bloat-o-meter: Ignore syscall aliases SyS_ and compat_SyS_
  mm: Support compiling out madvise and fadvise
  x86: Support compiling out human-friendly processor feature names
  x86: Drop support for /proc files when !CONFIG_PROC_FS
  x86, boot: Don't compile early_serial_console.c when !CONFIG_EARLY_PRINTK
  x86, boot: Don't compile aslr.c when !CONFIG_RANDOMIZE_BASE
  x86, boot: Use the usual -y -n mechanism for objects in vmlinux
  x86: Add "make tinyconfig" to configure the tiniest possible kernel
  x86, platform, kconfig: move kvmconfig functionality to a helper

17 files changed, 126 insertions, 56 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 36327438caf0..e4b1f431c7ed 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -137,6 +137,7 @@ config X86
         select HAVE_ACPI_APEI if ACPI
         select HAVE_ACPI_APEI_NMI if ACPI
         select ACPI_LEGACY_TABLES_LOOKUP if ACPI
+        select X86_FEATURE_NAMES if PROC_FS
 
 config INSTRUCTION_DECODER
         def_bool y
@@ -314,6 +315,17 @@ config SMP
 
           If you don't know what to do here, say N.
 
+config X86_FEATURE_NAMES
+        bool "Processor feature human-readable names" if EMBEDDED
+        default y
+        ---help---
+          This option compiles in a table of x86 feature bits and corresponding
+          names.  This is required to support /proc/cpuinfo and a few kernel
+          messages.  You can disable this to save space, at the expense of
+          making those few kernel messages show numeric feature bits instead.
+
+          If in doubt, say Y.
+
 config X86_X2APIC
         bool "Support x2apic"
         depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 60087ca37679..5692d6ac0f18 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -253,12 +253,6 @@ archclean:
         $(Q)$(MAKE) $(clean)=arch/x86/tools
         $(Q)$(MAKE) $(clean)=arch/x86/purgatory
 
-PHONY += kvmconfig
-kvmconfig:
-        $(if $(wildcard $(objtree)/.config),, $(error You need an existing .config for this target))
-        $(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh -m -O $(objtree) $(objtree)/.config $(srctree)/arch/x86/configs/kvm_guest.config
-        $(Q)yes "" | $(MAKE) -f $(srctree)/Makefile oldconfig
-
 define archhelp
   echo  '* bzImage      - Compressed kernel image (arch/x86/boot/bzImage)'
   echo  '  install      - Install kernel using'
@@ -272,5 +266,4 @@ define archhelp
   echo  '                  bzdisk/fdimage*/isoimage also accept:'
   echo  '                  FDARGS="..."  arguments for the booted kernel'
   echo  '                  FDINITRD=file initrd for the booted kernel'
-  echo  '  kvmconfig    - Enable additional options for guest kernel support'
 endef
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index dbe8dd2fe247..5b016e2498f3 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -35,19 +35,22 @@ setup-y		+= video-vesa.o
 setup-y         += video-bios.o
 
 targets         += $(setup-y)
-hostprogs-y     := mkcpustr tools/build
+hostprogs-y     := tools/build
+hostprogs-$(CONFIG_X86_FEATURE_NAMES) += mkcpustr
 
 HOST_EXTRACFLAGS += -I$(srctree)/tools/include \
                     -include include/generated/autoconf.h \
                     -D__EXPORTED_HEADERS__
 
+ifdef CONFIG_X86_FEATURE_NAMES
 $(obj)/cpu.o: $(obj)/cpustr.h
 
 quiet_cmd_cpustr = CPUSTR  $@
       cmd_cpustr = $(obj)/mkcpustr > $@
-targets         += cpustr.h
+targets += cpustr.h
 $(obj)/cpustr.h: $(obj)/mkcpustr FORCE
         $(call if_changed,cpustr)
+endif
 
 # ---------------------------------------------------------------------------
 
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 0fcd9133790c..704f58aa79cd 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -26,17 +26,18 @@ LDFLAGS_vmlinux := -T
 hostprogs-y     := mkpiggy
 HOST_EXTRACFLAGS += -I$(srctree)/tools/include
 
-VMLINUX_OBJS = $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
-        $(obj)/string.o $(obj)/cmdline.o $(obj)/early_serial_console.o \
-        $(obj)/piggy.o $(obj)/cpuflags.o $(obj)/aslr.o
+vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
+        $(obj)/string.o $(obj)/cmdline.o \
+        $(obj)/piggy.o $(obj)/cpuflags.o
+
+vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
+vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/aslr.o
 
 $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
 
-ifeq ($(CONFIG_EFI_STUB), y)
-        VMLINUX_OBJS += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o
-endif
+vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o
 
-$(obj)/vmlinux: $(VMLINUX_OBJS) FORCE
+$(obj)/vmlinux: $(vmlinux-objs-y) FORCE
         $(call if_changed,ld)
         @:
 
@@ -44,7 +45,7 @@ OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S
 $(obj)/vmlinux.bin: vmlinux FORCE
         $(call if_changed,objcopy)
 
-targets += $(patsubst $(obj)/%,%,$(VMLINUX_OBJS)) vmlinux.bin.all vmlinux.relocs
+targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs
 
 CMD_RELOCS = arch/x86/tools/relocs
 quiet_cmd_relocs = RELOCS  $@
diff --git a/arch/x86/boot/compressed/aslr.c b/arch/x86/boot/compressed/aslr.c
index d39189ba7f8e..7c68808edeb7 100644
--- a/arch/x86/boot/compressed/aslr.c
+++ b/arch/x86/boot/compressed/aslr.c
@@ -1,6 +1,5 @@
 #include "misc.h"
 
-#ifdef CONFIG_RANDOMIZE_BASE
 #include <asm/msr.h>
 #include <asm/archrandom.h>
 #include <asm/e820.h>
@@ -335,5 +334,3 @@ unsigned char *choose_kernel_location(unsigned char *input,
 out:
         return (unsigned char *)choice;
 }
-
-#endif /* CONFIG_RANDOMIZE_BASE */
diff --git a/arch/x86/boot/compressed/early_serial_console.c b/arch/x86/boot/compressed/early_serial_console.c
index d3d003cb5481..261e81fb9582 100644
--- a/arch/x86/boot/compressed/early_serial_console.c
+++ b/arch/x86/boot/compressed/early_serial_console.c
@@ -1,9 +1,5 @@
 #include "misc.h"
 
-#ifdef CONFIG_EARLY_PRINTK
-
 int early_serial_base;
 
 #include "../early_serial_console.c"
-
-#endif
diff --git a/arch/x86/boot/cpu.c b/arch/x86/boot/cpu.c
index 6ec6bb6e9957..29207f69ae8c 100644
--- a/arch/x86/boot/cpu.c
+++ b/arch/x86/boot/cpu.c
@@ -16,7 +16,9 @@
  */
 
 #include "boot.h"
+#ifdef CONFIG_X86_FEATURE_NAMES
 #include "cpustr.h"
+#endif
 
 static char *cpu_name(int level)
 {
@@ -32,11 +34,48 @@ static char *cpu_name(int level)
         }
 }
 
+static void show_cap_strs(u32 *err_flags)
+{
+        int i, j;
+#ifdef CONFIG_X86_FEATURE_NAMES
+        const unsigned char *msg_strs = (const unsigned char *)x86_cap_strs;
+        for (i = 0; i < NCAPINTS; i++) {
+                u32 e = err_flags[i];
+                for (j = 0; j < 32; j++) {
+                        if (msg_strs[0] < i ||
+                            (msg_strs[0] == i && msg_strs[1] < j)) {
+                                /* Skip to the next string */
+                                msg_strs += 2;
+                                while (*msg_strs++)
+                                        ;
+                        }
+                        if (e & 1) {
+                                if (msg_strs[0] == i &&
+                                    msg_strs[1] == j &&
+                                    msg_strs[2])
+                                        printf("%s ", msg_strs+2);
+                                else
+                                        printf("%d:%d ", i, j);
+                        }
+                        e >>= 1;
+                }
+        }
+#else
+        for (i = 0; i < NCAPINTS; i++) {
+                u32 e = err_flags[i];
+                for (j = 0; j < 32; j++) {
+                        if (e & 1)
+                                printf("%d:%d ", i, j);
+                        e >>= 1;
+                }
+        }
+#endif
+}
+
 int validate_cpu(void)
 {
         u32 *err_flags;
         int cpu_level, req_level;
-        const unsigned char *msg_strs;
 
         check_cpu(&cpu_level, &req_level, &err_flags);
 
@@ -49,34 +88,9 @@ int validate_cpu(void)
         }
 
         if (err_flags) {
-                int i, j;
                 puts("This kernel requires the following features "
                      "not present on the CPU:\n");
-
-                msg_strs = (const unsigned char *)x86_cap_strs;
-
-                for (i = 0; i < NCAPINTS; i++) {
-                        u32 e = err_flags[i];
-
-                        for (j = 0; j < 32; j++) {
-                                if (msg_strs[0] < i ||
-                                    (msg_strs[0] == i && msg_strs[1] < j)) {
-                                        /* Skip to the next string */
-                                        msg_strs += 2;
-                                        while (*msg_strs++)
-                                                ;
-                                }
-                                if (e & 1) {
-                                        if (msg_strs[0] == i &&
-                                            msg_strs[1] == j &&
-                                            msg_strs[2])
-                                                printf("%s ", msg_strs+2);
-                                        else
-                                                printf("%d:%d ", i, j);
-                                }
-                                e >>= 1;
-                        }
-                }
+                show_cap_strs(err_flags);
                 putchar('\n');
                 return -1;
         } else {
diff --git a/arch/x86/configs/tiny.config b/arch/x86/configs/tiny.config
new file mode 100644
index 000000000000..4e2ecfa23c15
--- /dev/null
+++ b/arch/x86/configs/tiny.config
@@ -0,0 +1 @@
+CONFIG_NOHIGHMEM=y
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index bb9b258d60e7..516903b98e06 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -250,8 +250,15 @@
 #include <asm/asm.h>
 #include <linux/bitops.h>
 
+#ifdef CONFIG_X86_FEATURE_NAMES
 extern const char * const x86_cap_flags[NCAPINTS*32];
 extern const char * const x86_power_flags[32];
+#define X86_CAP_FMT "%s"
+#define x86_cap_flag(flag) x86_cap_flags[flag]
+#else
+#define X86_CAP_FMT "%d:%d"
+#define x86_cap_flag(flag) ((flag) >> 5), ((flag) & 31)
+#endif
 
 /*
  * In order to save room, we index into this array by doing
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 7fd54f09b011..77dcab277710 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -13,10 +13,13 @@ nostackp := $(call cc-option, -fno-stack-protector)
 CFLAGS_common.o         := $(nostackp)
 
 obj-y                   := intel_cacheinfo.o scattered.o topology.o
-obj-y                   += proc.o capflags.o powerflags.o common.o
+obj-y                   += common.o
 obj-y                   += rdrand.o
 obj-y                   += match.o
 
+obj-$(CONFIG_PROC_FS)   += proc.o
+obj-$(CONFIG_X86_FEATURE_NAMES) += capflags.o powerflags.o
+
 obj-$(CONFIG_X86_32)    += bugs.o
 obj-$(CONFIG_X86_64)    += bugs_64.o
 
@@ -48,6 +51,7 @@ obj-$(CONFIG_X86_LOCAL_APIC)		+= perfctr-watchdog.o perf_event_amd_ibs.o
 
 obj-$(CONFIG_HYPERVISOR_GUEST)          += vmware.o hypervisor.o mshyperv.o
 
+ifdef CONFIG_X86_FEATURE_NAMES
 quiet_cmd_mkcapflags = MKCAP   $@
       cmd_mkcapflags = $(CONFIG_SHELL) $(srctree)/$(src)/mkcapflags.sh $< $@
 
@@ -56,3 +60,4 @@ cpufeature = $(src)/../../include/asm/cpufeature.h
 targets += capflags.c
 $(obj)/capflags.c: $(cpufeature) $(src)/mkcapflags.sh FORCE
         $(call if_changed,mkcapflags)
+endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index e4ab2b42bd6f..c649f236e288 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -346,8 +346,8 @@ static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
                         continue;
 
                 printk(KERN_WARNING
-                       "CPU: CPU feature %s disabled, no CPUID level 0x%x\n",
-                                x86_cap_flags[df->feature], df->level);
+                       "CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n",
+                                x86_cap_flag(df->feature), df->level);
         }
 }
 
diff --git a/init/Kconfig b/init/Kconfig
index 80a6907f91c5..b48917717bae 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1540,6 +1540,16 @@ config AIO
           by some high performance threaded applications. Disabling
           this option saves about 7k.
 
+config ADVISE_SYSCALLS
+        bool "Enable madvise/fadvise syscalls" if EXPERT
+        default y
+        help
+          This option enables the madvise and fadvise syscalls, used by
+          applications to advise the kernel about their future memory or file
+          usage, improving performance. If building an embedded system where no
+          applications use these syscalls, you can disable this option to save
+          space.
+
 config PCI_QUIRKS
         default y
         bool "Enable PCI quirk workarounds" if EXPERT
diff --git a/kernel/configs/tiny.config b/kernel/configs/tiny.config
new file mode 100644
index 000000000000..c2de56ab0fce
--- /dev/null
+++ b/kernel/configs/tiny.config
@@ -0,0 +1,4 @@
+CONFIG_CC_OPTIMIZE_FOR_SIZE=y
+CONFIG_KERNEL_XZ=y
+CONFIG_OPTIMIZE_INLINING=y
+CONFIG_SLOB=y
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 391d4ddb6f4b..d4709d481053 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -156,6 +156,9 @@ cond_syscall(sys_process_vm_writev);
 cond_syscall(compat_sys_process_vm_readv);
 cond_syscall(compat_sys_process_vm_writev);
 cond_syscall(sys_uselib);
+cond_syscall(sys_fadvise64);
+cond_syscall(sys_fadvise64_64);
+cond_syscall(sys_madvise);
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read);
diff --git a/mm/Makefile b/mm/Makefile
index 632ae77e6070..fe7a053c0f45 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -3,7 +3,7 @@
 #
 
 mmu-y                   := nommu.o
-mmu-$(CONFIG_MMU)       := fremap.o gup.o highmem.o madvise.o memory.o mincore.o \
+mmu-$(CONFIG_MMU)       := fremap.o gup.o highmem.o memory.o mincore.o \
                            mlock.o mmap.o mprotect.o mremap.o msync.o rmap.o \
                            vmalloc.o pagewalk.o pgtable-generic.o
 
@@ -11,7 +11,7 @@ ifdef CONFIG_CROSS_MEMORY_ATTACH
 mmu-$(CONFIG_MMU)       += process_vm_access.o
 endif
 
-obj-y                   := filemap.o mempool.o oom_kill.o fadvise.o \
+obj-y                   := filemap.o mempool.o oom_kill.o \
                            maccess.o page_alloc.o page-writeback.o \
                            readahead.o swap.o truncate.o vmscan.o shmem.o \
                            util.o mmzone.o vmstat.o backing-dev.o \
@@ -28,6 +28,9 @@ else
         obj-y           += bootmem.o
 endif
 
+ifdef CONFIG_MMU
+        obj-$(CONFIG_ADVISE_SYSCALLS)   += fadvise.o madvise.o
+endif
 obj-$(CONFIG_HAVE_MEMBLOCK) += memblock.o
 
 obj-$(CONFIG_SWAP)      += page_io.o swap_state.o swapfile.o
diff --git a/scripts/bloat-o-meter b/scripts/bloat-o-meter
index 549d0ab8c662..23e78dcd12bf 100755
--- a/scripts/bloat-o-meter
+++ b/scripts/bloat-o-meter
@@ -20,6 +20,8 @@ def getsizes(file):
         if type in "tTdDbBrR":
             # strip generated symbols
             if name.startswith("__mod_"): continue
+            if name.startswith("SyS_"): continue
+            if name.startswith("compat_SyS_"): continue
             if name == "linux_banner": continue
             # statics and some other optimizations adds random .NUMBER
             name = re.sub(r'\.[0-9]+', '', name)
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index 9c4d2412fb72..ebf40f6edb4d 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -104,6 +104,23 @@ endif
 %_defconfig: $(obj)/conf
         $(Q)$< --defconfig=arch/$(SRCARCH)/configs/$@ $(Kconfig)
 
+configfiles=$(wildcard $(srctree)/kernel/configs/$(1).config $(srctree)/arch/$(SRCARCH)/configs/$(1).config)
+
+define mergeconfig
+$(if $(wildcard $(objtree)/.config),, $(error You need an existing .config for this target))
+$(if $(call configfiles,$(1)),, $(error No configuration exists for this target on this architecture))
+$(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh -m -O $(objtree) $(objtree)/.config $(call configfiles,$(1))
+$(Q)yes "" | $(MAKE) -f $(srctree)/Makefile oldconfig
+endef
+
+PHONY += kvmconfig
+kvmconfig:
+        $(call mergeconfig,kvm_guest)
+
+PHONY += tinyconfig
+tinyconfig: allnoconfig
+        $(call mergeconfig,tiny)
+
 # Help text used by make help
 help:
         @echo  '  config          - Update current config utilising a line-oriented program'
@@ -124,6 +141,8 @@ help:
         @echo  '  randconfig      - New config with random answer to all options'
         @echo  '  listnewconfig   - List new options'
         @echo  '  olddefconfig    - Same as silentoldconfig but sets new symbols to their default value'
+        @echo  '  kvmconfig       - Enable additional options for guest kernel support'
+        @echo  '  tinyconfig      - Configure the tiniest possible kernel'
 
 # lxdialog stuff
 check-lxdialog  := $(srctree)/$(src)/lxdialog/check-lxdialog.sh