talos-obmc-linux/kernel/Makefile, branch dev-4.13

kernel/watchdog: split up config options

2017-07-12T23:26:02+00:00

Split SOFTLOCKUP_DETECTOR from LOCKUP_DETECTOR, and split HARDLOCKUP_DETECTOR_PERF from HARDLOCKUP_DETECTOR. LOCKUP_DETECTOR implies the general boot, sysctl, and programming interfaces for the lockup detectors. An architecture that wants to use a hard lockup detector must define HAVE_HARDLOCKUP_DETECTOR_PERF or HAVE_HARDLOCKUP_DETECTOR_ARCH. Alternatively an arch can define HAVE_NMI_WATCHDOG, which provides the minimum arch_touch_nmi_watchdog, and it otherwise does its own thing and does not implement the LOCKUP_DETECTOR interfaces. sparc is unusual in that it has started to implement some of the interfaces, but not fully yet. It should probably be converted to a full HAVE_HARDLOCKUP_DETECTOR_ARCH. [npiggin@gmail.com: fix] Link: http://lkml.kernel.org/r/20170617223522.66c0ad88@roar.ozlabs.ibm.com Link: http://lkml.kernel.org/r/20170616065715.18390-4-npiggin@gmail.com Signed-off-by: Nicholas Piggin Reviewed-by: Don Zickus Reviewed-by: Babu Moger Tested-by: Babu Moger [sparc] Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE

2017-05-09T00:15:11+00:00

Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and reuse crashkernel parameter for fadump", v4. Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. This patchset removes dependency with CONFIG_KEXEC for crashkernel parameter and vmcoreinfo related code as it can be reused without kexec support. Also, crashkernel parameter is reused instead of fadump_reserve_mem to reserve memory for fadump. The first patch moves crashkernel parameter parsing and vmcoreinfo related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE. The second patch reuses the definitions of append_elf_note() & final_note() functions under CONFIG_CRASH_CORE in IA64 arch code. The third patch removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump) in powerpc. The next patch reuses crashkernel parameter for reserving memory for fadump, instead of the fadump_reserve_mem parameter. This has the advantage of using all syntaxes crashkernel parameter supports, for fadump as well. The last patch updates fadump kernel documentation about use of crashkernel parameter. This patch (of 5): Traditionally, kdump is used to save vmcore in case of a crash. Some architectures like powerpc can save vmcore using architecture specific support instead of kexec/kdump mechanism. Such architecture specific support also needs to reserve memory, to be used by dump capture kernel. crashkernel parameter can be a reused, for memory reservation, by such architecture specific infrastructure. But currently, code related to vmcoreinfo and parsing of crashkernel parameter is built under CONFIG_KEXEC_CORE. This patch introduces CONFIG_CRASH_CORE and moves the above mentioned code under this config, allowing code reuse without dependency on CONFIG_KEXEC. There is no functional change with this patch. Link: http://lkml.kernel.org/r/149035338104.6881.4550894432615189948.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini Acked-by: Dave Young Cc: Fenghua Yu Cc: Tony Luck Cc: Eric Biederman Cc: Mahesh Salgaonkar Cc: Vivek Goyal Cc: Michael Ellerman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

cgroup: move cgroup files under kernel/cgroup/

2016-12-27T19:49:05+00:00

They're growing to be too many and planned to get split further. Move them under their own directory. kernel/cgroup.c -> kernel/cgroup/cgroup.c kernel/cgroup_freezer.c -> kernel/cgroup/freezer.c kernel/cgroup_pids.c -> kernel/cgroup/pids.c kernel/cpuset.c -> kernel/cgroup/cpuset.c Signed-off-by: Tejun Heo Acked-by: Acked-by: Zefan Li

Merge branch 'akpm' (patches from Andrew)

2016-12-15T01:25:18+00:00

Merge more updates from Andrew Morton: - a few misc things - kexec updates - DMA-mapping updates to better support networking DMA operations - IPC updates - various MM changes to improve DAX fault handling - lots of radix-tree changes, mainly to the test suite. All leading up to reimplementing the IDA/IDR code to be a wrapper layer over the radix-tree. However the final trigger-pulling patch is held off for 4.11. * emailed patches from Andrew Morton : (114 commits) radix tree test suite: delete unused rcupdate.c radix tree test suite: add new tag check radix-tree: ensure counts are initialised radix tree test suite: cache recently freed objects radix tree test suite: add some more functionality idr: reduce the number of bits per level from 8 to 6 rxrpc: abstract away knowledge of IDR internals tpm: use idr_find(), not idr_find_slowpath() idr: add ida_is_empty radix tree test suite: check multiorder iteration radix-tree: fix replacement for multiorder entries radix-tree: add radix_tree_split_preload() radix-tree: add radix_tree_split radix-tree: add radix_tree_join radix-tree: delete radix_tree_range_tag_if_tagged() radix-tree: delete radix_tree_locate_item() radix-tree: improve multiorder iterators btrfs: fix race in btrfs_free_dummy_fs_info() radix-tree: improve dump output radix-tree: make radix_tree_find_next_bit more useful ...

kernel/watchdog.c: move hardlockup detector to separate file

2016-12-15T00:04:08+00:00

Separate hardlockup code from watchdog.c and move it to watchdog_hld.c. It is mostly straight forward. Remove everything inside CONFIG_HARDLOCKUP_DETECTORS. This code will go to file watchdog_hld.c. Also update the makefile accordigly. Link: http://lkml.kernel.org/r/1478034826-43888-3-git-send-email-babu.moger@oracle.com Signed-off-by: Babu Moger Acked-by: Don Zickus Cc: Ingo Molnar Cc: Jiri Kosina Cc: Andi Kleen Cc: Yaowei Bai Cc: Aaron Tomlin Cc: Ulrich Obergfell Cc: Tejun Heo Cc: Hidehiro Kawai Cc: Josh Hunt Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Remove last traces of ikconfig.h

2016-12-14T09:54:28+00:00

The build system stopped generating ikconfig.h in v2.6.8. Remove an entry for it in dontdiff. There's also a reference to it in a small comment. Remove that comment too, as it is of little help in any case. Signed-off-by: Paul Bolle Signed-off-by: Jiri Kosina

userns: Add per user namespace sysctls.

2016-08-08T18:18:58+00:00

Limit per userns sysctls to only be opened for write by a holder of CAP_SYS_RESOURCE. Add all of the necessary boilerplate for having per user namespace sysctls. Acked-by: Kees Cook Signed-off-by: "Eric W. Biederman"

ELF/MIPS build fix

2016-05-24T00:04:14+00:00

CONFIG_MIPS32_N32=y but CONFIG_BINFMT_ELF disabled results in the following linker errors: arch/mips/built-in.o: In function `elf_core_dump': binfmt_elfn32.c:(.text+0x23dbc): undefined reference to `elf_core_extra_phdrs' binfmt_elfn32.c:(.text+0x246e4): undefined reference to `elf_core_extra_data_size' binfmt_elfn32.c:(.text+0x248d0): undefined reference to `elf_core_write_extra_phdrs' binfmt_elfn32.c:(.text+0x24ac4): undefined reference to `elf_core_write_extra_data' CONFIG_MIPS32_O32=y but CONFIG_BINFMT_ELF disabled results in the following linker errors: arch/mips/built-in.o: In function `elf_core_dump': binfmt_elfo32.c:(.text+0x28a04): undefined reference to `elf_core_extra_phdrs' binfmt_elfo32.c:(.text+0x29330): undefined reference to `elf_core_extra_data_size' binfmt_elfo32.c:(.text+0x2951c): undefined reference to `elf_core_write_extra_phdrs' binfmt_elfo32.c:(.text+0x29710): undefined reference to `elf_core_write_extra_data' This is because binfmt_elfn32 and binfmt_elfo32 are using symbols from elfcore but for these configurations elfcore will not be built. Fixed by making elfcore selectable by a separate config symbol which unlike the current mechanism can also be used from other directories than kernel/, then having each flavor of ELF that relies on elfcore.o, select it in Kconfig, including CONFIG_MIPS32_N32 and CONFIG_MIPS32_O32 which fixes this issue. Link: http://lkml.kernel.org/r/20160520141705.GA1913@linux-mips.org Signed-off-by: Ralf Baechle Reviewed-by: James Hogan Cc: "Maciej W. Rozycki" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kernel: add kcov code coverage

2016-03-22T22:36:02+00:00

kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system. A notable user-space example is AFL (http://lcamtuf.coredump.cx/afl/). However, this technique is not widely used for kernel testing due to missing compiler and kernel support. kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disbled (e.g. scheduler, locking). Currently there is a single coverage collection mode (tracing), but the API anticipates additional collection modes. Initially I also implemented a second mode which exposes coverage in a fixed-size hash table of counters (what Quentin used in his original patch). I've dropped the second mode for simplicity. This patch adds the necessary support on kernel side. The complimentary compiler support was added in gcc revision 231296. We've used this support to build syzkaller system call fuzzer, which has found 90 kernel bugs in just 2 months: https://github.com/google/syzkaller/wiki/Found-Bugs We've also found 30+ bugs in our internal systems with syzkaller. Another (yet unexplored) direction where kcov coverage would greatly help is more traditional "blob mutation". For example, mounting a random blob as a filesystem, or receiving a random blob over wire. Why not gcov. Typical fuzzing loop looks as follows: (1) reset coverage, (2) execute a bit of code, (3) collect coverage, repeat. A typical coverage can be just a dozen of basic blocks (e.g. an invalid input). In such context gcov becomes prohibitively expensive as reset/collect coverage steps depend on total number of basic blocks/edges in program (in case of kernel it is about 2M). Cost of kcov depends only on number of executed basic blocks/edges. On top of that, kernel requires per-thread coverage because there are always background threads and unrelated processes that also produce coverage. With inlined gcov instrumentation per-thread coverage is not possible. kcov exposes kernel PCs and control flow to user-space which is insecure. But debugfs should not be mapped as user accessible. Based on a patch by Quentin Casasnovas. [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode'] [akpm@linux-foundation.org: unbreak allmodconfig] [akpm@linux-foundation.org: follow x86 Makefile layout standards] Signed-off-by: Dmitry Vyukov Reviewed-by: Kees Cook Cc: syzkaller Cc: Vegard Nossum Cc: Catalin Marinas Cc: Tavis Ormandy Cc: Will Deacon Cc: Quentin Casasnovas Cc: Kostya Serebryany Cc: Eric Dumazet Cc: Alexander Potapenko Cc: Kees Cook Cc: Bjorn Helgaas Cc: Sasha Levin Cc: David Drysdale Cc: Ard Biesheuvel Cc: Andrey Ryabinin Cc: Kirill A. Shutemov Cc: Jiri Slaby Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kernel/Makefile: remove the useless CFLAGS_REMOVE_cgroup-debug.o

2016-01-31T10:11:21+00:00

The file cgroup-debug.c had been removed from commit fe6934354f8e (cgroups: move the cgroup debug subsys into cgroup.c to access internal state). Remain the CFLAGS_REMOVE_cgroup-debug.o = $(CC_FLAGS_FTRACE) useless in kernel/Makefile. Signed-off-by: Li Bin Acked-by: Zefan Li Signed-off-by: Tejun Heo