# git rev-parse -q --verify 574823bfab82d9d8fa47f422778043fbb4b4f50e^{commit} 574823bfab82d9d8fa47f422778043fbb4b4f50e already have revision, skipping fetch # git checkout -q -f -B kisskb 574823bfab82d9d8fa47f422778043fbb4b4f50e # git clean -qxdf # < git log -1 # commit 574823bfab82d9d8fa47f422778043fbb4b4f50e # Author: Linus Torvalds # Date: Sat Jan 5 17:50:59 2019 -0800 # # Change mincore() to count "mapped" pages rather than "cached" pages # # The semantics of what "in core" means for the mincore() system call are # somewhat unclear, but Linux has always (since 2.3.52, which is when # mincore() was initially done) treated it as "page is available in page # cache" rather than "page is mapped in the mapping". # # The problem with that traditional semantic is that it exposes a lot of # system cache state that it really probably shouldn't, and that users # shouldn't really even care about. # # So let's try to avoid that information leak by simply changing the # semantics to be that mincore() counts actual mapped pages, not pages # that might be cheaply mapped if they were faulted (note the "might be" # part of the old semantics: being in the cache doesn't actually guarantee # that you can access them without IO anyway, since things like network # filesystems may have to revalidate the cache before use). # # In many ways the old semantics were somewhat insane even aside from the # information leak issue. From the very beginning (and that beginning is # a long time ago: 2.3.52 was released in March 2000, I think), the code # had a comment saying # # Later we can get more picky about what "in core" means precisely. # # and this is that "later". Admittedly it is much later than is really # comfortable. # # NOTE! This is a real semantic change, and it is for example known to # change the output of "fincore", since that program literally does a # mmmap without populating it, and then doing "mincore()" on that mapping # that doesn't actually have any pages in it. # # I'm hoping that nobody actually has any workflow that cares, and the # info leak is real. # # We may have to do something different if it turns out that people have # valid reasons to want the old semantics, and if we can limit the # information leak sanely. # # Cc: Kevin Easton # Cc: Jiri Kosina # Cc: Masatake YAMATO # Cc: Andrew Morton # Cc: Greg KH # Cc: Peter Zijlstra # Cc: Michal Hocko # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/gcc-4.6.3-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version # < /opt/cross/kisskb/gcc-4.6.3-nolibc/x86_64-linux/bin/x86_64-linux-ld --version # < git log --format=%s --max-count=1 574823bfab82d9d8fa47f422778043fbb4b4f50e # < make -s -j 8 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/x86_64-linux/bin/x86_64-linux- randconfig KCONFIG_SEED=0xDE9C4AB3 WARNING: unmet direct dependencies detected for PINCTRL_MTK_MOORE Depends on [n]: PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && OF [=n] Selected by [y]: - PINCTRL_MT7623 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && (MACH_MT7623 || COMPILE_TEST [=y]) WARNING: unmet direct dependencies detected for PINCTRL_MTK_MOORE Depends on [n]: PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && OF [=n] Selected by [y]: - PINCTRL_MT7623 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && (MACH_MT7623 || COMPILE_TEST [=y]) WARNING: unmet direct dependencies detected for INTEL_SOC_DTS_IOSF_CORE Depends on [n]: THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && PCI [=n] Selected by [y]: - INT340X_THERMAL [=y] && THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && ACPI [=y] WARNING: unmet direct dependencies detected for IOSF_MBI Depends on [n]: PCI [=n] Selected by [y]: - X86_INTEL_LPSS [=y] && X86 [=y] && ACPI [=y] - MMC_SDHCI_ACPI [=y] && MMC [=y] && MMC_SDHCI [=y] && ACPI [=y] && X86 [=y] WARNING: unmet direct dependencies detected for PINCTRL_MTK_MOORE Depends on [n]: PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && OF [=n] Selected by [y]: - PINCTRL_MT7623 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && (MACH_MT7623 || COMPILE_TEST [=y]) WARNING: unmet direct dependencies detected for INTEL_SOC_DTS_IOSF_CORE Depends on [n]: THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && PCI [=n] Selected by [y]: - INT340X_THERMAL [=y] && THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && ACPI [=y] WARNING: unmet direct dependencies detected for IOSF_MBI Depends on [n]: PCI [=n] Selected by [y]: - X86_INTEL_LPSS [=y] && X86 [=y] && ACPI [=y] - MMC_SDHCI_ACPI [=y] && MMC [=y] && MMC_SDHCI [=y] && ACPI [=y] && X86 [=y] # Added to kconfig CONFIG_STANDALONE=y # Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y # Added to kconfig CONFIG_CC_STACKPROTECTOR_STRONG=n # Added to kconfig CONFIG_GCC_PLUGINS=n # Added to kconfig CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=n # Added to kconfig CONFIG_GCC_PLUGIN_SANCOV=n # Added to kconfig CONFIG_GCC_PLUGIN_LATENT_ENTROPY=n # yes \n | make -s -j 8 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/x86_64-linux/bin/x86_64-linux- oldconfig yes: standard output: Broken pipe # make -s -j 8 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/x86_64-linux/bin/x86_64-linux- WARNING: unmet direct dependencies detected for PINCTRL_MTK_MOORE Depends on [n]: PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && OF [=n] Selected by [y]: - PINCTRL_MT7623 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && (MACH_MT7623 || COMPILE_TEST [=y]) WARNING: unmet direct dependencies detected for INTEL_SOC_DTS_IOSF_CORE Depends on [n]: THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && PCI [=n] Selected by [y]: - INT340X_THERMAL [=y] && THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && ACPI [=y] WARNING: unmet direct dependencies detected for IOSF_MBI Depends on [n]: PCI [=n] Selected by [y]: - X86_INTEL_LPSS [=y] && X86 [=y] && ACPI [=y] - MMC_SDHCI_ACPI [=y] && MMC [=y] && MMC_SDHCI [=y] && ACPI [=y] && X86 [=y] WARNING: unmet direct dependencies detected for PINCTRL_MTK_MOORE Depends on [n]: PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && OF [=n] Selected by [y]: - PINCTRL_MT7623 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && (MACH_MT7623 || COMPILE_TEST [=y]) WARNING: unmet direct dependencies detected for INTEL_SOC_DTS_IOSF_CORE Depends on [n]: THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && PCI [=n] Selected by [y]: - INT340X_THERMAL [=y] && THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && ACPI [=y] WARNING: unmet direct dependencies detected for IOSF_MBI Depends on [n]: PCI [=n] Selected by [y]: - X86_INTEL_LPSS [=y] && X86 [=y] && ACPI [=y] - MMC_SDHCI_ACPI [=y] && MMC [=y] && MMC_SDHCI [=y] && ACPI [=y] && X86 [=y] WARNING: unmet direct dependencies detected for PINCTRL_MTK_MOORE Depends on [n]: PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && OF [=n] Selected by [y]: - PINCTRL_MT7623 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST [=y]) && (MACH_MT7623 || COMPILE_TEST [=y]) WARNING: unmet direct dependencies detected for INTEL_SOC_DTS_IOSF_CORE Depends on [n]: THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && PCI [=n] Selected by [y]: - INT340X_THERMAL [=y] && THERMAL [=y] && (X86 [=y] || X86_INTEL_QUARK [=n] || COMPILE_TEST [=y]) && X86 [=y] && ACPI [=y] WARNING: unmet direct dependencies detected for IOSF_MBI Depends on [n]: PCI [=n] Selected by [y]: - X86_INTEL_LPSS [=y] && X86 [=y] && ACPI [=y] - MMC_SDHCI_ACPI [=y] && MMC [=y] && MMC_SDHCI [=y] && ACPI [=y] && X86 [=y] /kisskb/src/arch/x86/kernel/apic/io_apic.c: In function 'mp_map_pin_to_irq': /kisskb/src/arch/x86/kernel/apic/io_apic.c:1034:6: warning: 'irq' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/ipc/shm.c: In function 'ksys_shmdt': /kisskb/src/ipc/shm.c:1686:59: warning: 'file' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/arch/x86/kernel/e820.c: In function 'e820__setup_pci_gap': /kisskb/src/arch/x86/kernel/e820.c:650:16: warning: 'gapstart' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:186:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/f2fs/node.c: In function '__set_nat_cache_dirty': /kisskb/src/fs/f2fs/node.c:264:17: warning: 'head' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/arch/x86/kernel/hw_breakpoint.c: In function 'hw_breakpoint_arch_parse': /kisskb/src/arch/x86/kernel/hw_breakpoint.c:366:18: warning: 'align' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/rcu/srcutree.c: In function 'init_srcu_struct_nodes': /kisskb/src/kernel/rcu/srcutree.c:133:34: warning: 'levelspread[]' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/mm/ksm.c: In function 'stable_node_dup': /kisskb/src/mm/ksm.c:1393:15: warning: 'found_rmap_hlist_len' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/gfs2/bmap.c: In function 'gfs2_iomap_get': /kisskb/src/fs/gfs2/bmap.c:922:18: warning: 'height' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/gfs2/bmap.c:917:7: warning: 'len' 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:339:21: note: 'pdeo' was declared here /kisskb/src/fs/udf/unicode.c: In function 'udf_name_conv_char': /kisskb/src/fs/udf/unicode.c:132:8: warning: 'c' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/char/tpm/tpm-sysfs.c: In function 'pubek_show': /kisskb/src/drivers/char/tpm/tpm-sysfs.c:56:5: warning: 'tpm_buf.data' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/acpi/acpi_lpss.c: In function 'acpi_lpss_find_device': /kisskb/src/drivers/acpi/acpi_lpss.c:538:26: error: 'pci_bus_type' undeclared (first use in this function) /kisskb/src/drivers/acpi/acpi_lpss.c:538:26: note: each undeclared identifier is reported only once for each function it appears in /kisskb/src/drivers/acpi/acpi_lpss.c:539:1: warning: control reaches end of non-void function [-Wreturn-type] make[3]: *** [/kisskb/src/scripts/Makefile.build:276: drivers/acpi/acpi_lpss.o] Error 1 make[3]: *** Waiting for unfinished jobs.... make[2]: *** [/kisskb/src/scripts/Makefile.build:492: drivers/acpi] Error 2 make[2]: *** Waiting for unfinished jobs.... /kisskb/src/lib/mpi/mpicoder.c: In function 'mpi_read_raw_from_sgl': /kisskb/src/lib/mpi/mpicoder.c:352:8: warning: 'buff' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/splice.c: In function '__do_sys_vmsplice': /kisskb/src/fs/splice.c:1362:22: warning: 'type' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/raid6/recov_avx512.c:387:2: warning: #warning "your version of binutils lacks AVX512 support" [-Wcpp] make[1]: *** [/kisskb/src/Makefile:1049: drivers] Error 2 make[1]: *** Waiting for unfinished jobs.... /kisskb/src/lib/rhashtable.c: In function 'rhashtable_rehash_one': /kisskb/src/lib/rhashtable.c:264:2: warning: 'next' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/string.c: In function 'strlcpy': /kisskb/src/lib/string.c:479:8: sorry, unimplemented: inlining failed in call to 'strlen': redefined extern inline functions are not considered for inlining /kisskb/src/lib/string.c:143:9: sorry, unimplemented: called from here make[2]: *** [/kisskb/src/scripts/Makefile.build:277: lib/string.o] Error 1 make[2]: *** Waiting for unfinished jobs.... make[1]: *** [/kisskb/src/Makefile:1049: lib] Error 2 make: *** [Makefile:152: sub-make] Error 2 Command 'make -s -j 8 ARCH=x86_64 O=/kisskb/build/linus-rand_x86_64-randconfig_x86_64 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/x86_64-linux/bin/x86_64-linux- ' returned non-zero exit status 2 # rm -rf /kisskb/build/linus-rand_x86_64-randconfig_x86_64 # Build took: 0:01:19.639153