# git rev-parse -q --verify 4aa9fc2a435abe95a1e8d7f8c7b3d6356514b37a^{commit} 4aa9fc2a435abe95a1e8d7f8c7b3d6356514b37a already have revision, skipping fetch # git checkout -q -f -B kisskb 4aa9fc2a435abe95a1e8d7f8c7b3d6356514b37a # git clean -qxdf # < git log -1 # commit 4aa9fc2a435abe95a1e8d7f8c7b3d6356514b37a # Author: Michal Hocko # Date: Fri Jan 25 19:08:58 2019 +0100 # # Revert "mm, memory_hotplug: initialize struct pages for the full memory section" # # This reverts commit 2830bf6f05fb3e05bc4743274b806c821807a684. # # The underlying assumption that one sparse section belongs into a single # numa node doesn't hold really. Robert Shteynfeld has reported a boot # failure. The boot log was not captured but his memory layout is as # follows: # # Early memory node ranges # node 1: [mem 0x0000000000001000-0x0000000000090fff] # node 1: [mem 0x0000000000100000-0x00000000dbdf8fff] # node 1: [mem 0x0000000100000000-0x0000001423ffffff] # node 0: [mem 0x0000001424000000-0x0000002023ffffff] # # This means that node0 starts in the middle of a memory section which is # also in node1. memmap_init_zone tries to initialize padding of a # section even when it is outside of the given pfn range because there are # code paths (e.g. memory hotplug) which assume that the full worth of # memory section is always initialized. # # In this particular case, though, such a range is already intialized and # most likely already managed by the page allocator. Scribbling over # those pages corrupts the internal state and likely blows up when any of # those pages gets used. # # Reported-by: Robert Shteynfeld # Fixes: 2830bf6f05fb ("mm, memory_hotplug: initialize struct pages for the full memory section") # Cc: stable@kernel.org # Signed-off-by: Michal Hocko # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-gcc --version # < /opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux-ld --version # < git log --format=%s --max-count=1 4aa9fc2a435abe95a1e8d7f8c7b3d6356514b37a # < make -s -j 48 ARCH=um O=/kisskb/build/linus_um-allmodconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 allmodconfig # Added to kconfig CONFIG_STANDALONE=y # Added to kconfig CONFIG_KCOV=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 # Added to kconfig CONFIG_GCC_PLUGIN_STRUCTLEAK=n # Added to kconfig CONFIG_GCC_PLUGIN_RANDSTRUCT=n # Added to kconfig CONFIG_UML_NET=n # Added to kconfig CONFIG_UML_NET_ETHERTAP=n # Added to kconfig CONFIG_UML_NET_TUNTAP=n # Added to kconfig CONFIG_UML_NET_SLIP=n # Added to kconfig CONFIG_UML_NET_DAEMON=n # Added to kconfig CONFIG_UML_NET_VDE=n # Added to kconfig CONFIG_UML_NET_MCAST=n # Added to kconfig CONFIG_UML_NET_PCAP=n # Added to kconfig CONFIG_UML_NET_SLIRP=n # Added to kconfig CONFIG_GCOV_KERNEL=n # yes \n | make -s -j 48 ARCH=um O=/kisskb/build/linus_um-allmodconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 oldconfig yes: standard output: Broken pipe # make -s -j 48 ARCH=um O=/kisskb/build/linus_um-allmodconfig_um-x86_64 CROSS_COMPILE=/opt/cross/kisskb/fe-x86-64-core-i7-2017.05/bin/x86_64-linux- SUBARCH=x86_64 /kisskb/src/arch/um/kernel/skas/uaccess.c: In function 'do_op_one_page': /kisskb/src/arch/um/kernel/skas/uaccess.c:62:10: warning: unused variable 'buf' [-Wunused-variable] jmp_buf buf; ^ /kisskb/src/kernel/bpf/verifier.c: In function 'check_btf_info': /kisskb/src/kernel/bpf/verifier.c:5065:4: warning: 'prev_offset' may be used uninitialized in this function [-Wmaybe-uninitialized] verbose(env, ^ /kisskb/src/kernel/bpf/verifier.c:5000:38: note: 'prev_offset' was declared here u32 i, nfuncs, urec_size, min_size, prev_offset; ^ /kisskb/src/arch/um/os-Linux/umid.c: In function 'is_umdir_used': /kisskb/src/arch/um/os-Linux/umid.c:138:2: warning: ISO C90 forbids variable length array 'file' [-Wvla] char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")]; ^ /kisskb/src/arch/um/os-Linux/umid.c: In function 'create_pid_file': /kisskb/src/arch/um/os-Linux/umid.c:213:2: warning: ISO C90 forbids variable length array 'file' [-Wvla] char file[strlen(uml_dir) + UMID_LEN + sizeof("/pid\0")]; ^ /kisskb/src/arch/um/os-Linux/umid.c: In function 'remove_umid_dir': /kisskb/src/arch/um/os-Linux/umid.c:388:2: warning: ISO C90 forbids variable length array 'dir' [-Wvla] char dir[strlen(uml_dir) + UMID_LEN + 1], err; ^ /kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount': /kisskb/src/kernel/cgroup/cgroup-v1.c:1263:3: warning: 'root' may be used uninitialized in this function [-Wmaybe-uninitialized] percpu_ref_reinit(&root->cgrp.self.refcnt); ^ /kisskb/src/security/apparmor/policy_unpack.c: In function 'unpack_trans_table': /kisskb/src/security/apparmor/policy_unpack.c:496:9: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized] str[pos] = ':'; ^ /kisskb/src/lib/lz4/lz4hc_compress.c: In function 'LZ4HC_compress_generic': /kisskb/src/lib/lz4/lz4hc_compress.c:579:1: warning: the frame size of 2144 bytes is larger than 2048 bytes [-Wframe-larger-than=] } ^ /kisskb/src/drivers/i2c/i2c-core-base.c: In function 'i2c_generic_scl_recovery': /kisskb/src/drivers/i2c/i2c-core-base.c:235:5: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized] if (ret == -EOPNOTSUPP) ^ LINK linux Completed OK # rm -rf /kisskb/build/linus_um-allmodconfig_um-x86_64 # Build took: 0:04:53.710144