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741c74f55e
1486 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Linus Torvalds
|
086e3eb65e |
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton: "Two weeks worth of fixes here" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits) init/main.c: fix initcall_blacklisted on ia64, ppc64 and parisc64 autofs: don't get stuck in a loop if vfs_write() returns an error mm/page_owner: avoid null pointer dereference tools/vm/slabinfo: fix spelling mistake: "Ocurrences" -> "Occurrences" fs/nilfs2: fix potential underflow in call to crc32_le oom, suspend: fix oom_reaper vs. oom_killer_disable race ocfs2: disable BUG assertions in reading blocks mm, compaction: abort free scanner if split fails mm: prevent KASAN false positives in kmemleak mm/hugetlb: clear compound_mapcount when freeing gigantic pages mm/swap.c: flush lru pvecs on compound page arrival memcg: css_alloc should return an ERR_PTR value on error memcg: mem_cgroup_migrate() may be called with irq disabled hugetlb: fix nr_pmds accounting with shared page tables Revert "mm: disable fault around on emulated access bit architecture" Revert "mm: make faultaround produce old ptes" mailmap: add Boris Brezillon's email mailmap: add Antoine Tenart's email mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask mm: mempool: kasan: don't poot mempool objects in quarantine ... |
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Rasmus Villemoes
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0fd5ed8d89 |
init/main.c: fix initcall_blacklisted on ia64, ppc64 and parisc64
When I replaced kasprintf("%pf") with a direct call to
sprint_symbol_no_offset I must have broken the initcall blacklisting
feature on the arches where dereference_function_descriptor() is
non-trivial.
Fixes:
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Linus Torvalds
|
b235beea9e |
Clarify naming of thread info/stack allocators
We've had the thread info allocated together with the thread stack for most architectures for a long time (since the thread_info was split off from the task struct), but that is about to change. But the patches that move the thread info to be off-stack (and a part of the task struct instead) made it clear how confused the allocator and freeing functions are. Because the common case was that we share an allocation with the thread stack and the thread_info, the two pointers were identical. That identity then meant that we would have things like ti = alloc_thread_info_node(tsk, node); ... tsk->stack = ti; which certainly _worked_ (since stack and thread_info have the same value), but is rather confusing: why are we assigning a thread_info to the stack? And if we move the thread_info away, the "confusing" code just gets to be entirely bogus. So remove all this confusion, and make it clear that we are doing the stack allocation by renaming and clarifying the function names to be about the stack. The fact that the thread_info then shares the allocation is an implementation detail, and not really about the allocation itself. This is a pure renaming and type fix: we pass in the same pointer, it's just that we clarify what the pointer means. The ia64 code that actually only has one single allocation (for all of task_struct, thread_info and kernel thread stack) now looks a bit odd, but since "tsk->stack" is actually not even used there, that oddity doesn't matter. It would be a separate thing to clean that up, I intentionally left the ia64 changes as a pure brute-force renaming and type change. Acked-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Yang Shi
|
fe53ca5427 |
mm: use early_pfn_to_nid in page_ext_init
page_ext_init() checks suitable pages with pfn_to_nid(), but
pfn_to_nid() depends on memmap which will not be setup fully until
page_alloc_init_late() is done. Use early_pfn_to_nid() instead of
pfn_to_nid() so that page extension could be still used early even
though CONFIG_ DEFERRED_STRUCT_PAGE_INIT is enabled and catch early page
allocation call sites.
Suggested by Joonsoo Kim [1], this fix basically undoes the change
introduced by commit
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Linus Torvalds
|
5b26fc8824 |
Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek: - new option CONFIG_TRIM_UNUSED_KSYMS which does a two-pass build and unexports symbols which are not used in the current config [Nicolas Pitre] - several kbuild rule cleanups [Masahiro Yamada] - warning option adjustments for gcov etc [Arnd Bergmann] - a few more small fixes * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (31 commits) kbuild: move -Wunused-const-variable to W=1 warning level kbuild: fix if_change and friends to consider argument order kbuild: fix adjust_autoksyms.sh for modules that need only one symbol kbuild: fix ksym_dep_filter when multiple EXPORT_SYMBOL() on the same line gcov: disable -Wmaybe-uninitialized warning gcov: disable tree-loop-im to reduce stack usage gcov: disable for COMPILE_TEST Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES Kbuild: change CC_OPTIMIZE_FOR_SIZE definition kbuild: forbid kernel directory to contain spaces and colons kbuild: adjust ksym_dep_filter for some cmd_* renames kbuild: Fix dependencies for final vmlinux link kbuild: better abstract vmlinux sequential prerequisites kbuild: fix call to adjust_autoksyms.sh when output directory specified kbuild: Get rid of KBUILD_STR kbuild: rename cmd_as_s_S to cmd_cpp_s_S kbuild: rename cmd_cc_i_c to cmd_cpp_i_c kbuild: drop redundant "PHONY += FORCE" kbuild: delete unnecessary "@:" kbuild: mark help target as PHONY ... |
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Rasmus Villemoes
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c8cdd2be21 |
init/main.c: simplify initcall_blacklisted()
Using kasprintf to get the function name makes us look up the name twice, along with all the vsnprintf overhead of parsing the format string etc. It also means there is an allocation failure case to deal with. Since symbol_string in vsprintf.c would anyway allocate an array of size KSYM_SYMBOL_LEN on the stack, that might as well be done up here. Moreover, since this is a debug feature and the blacklisted_initcalls list is usually empty, we might as well test that and thus avoid looking up the symbol name even once in the common case. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Prarit Bhargava <prarit@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Petr Mladek
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427934b871 |
printk/nmi: increase the size of NMI buffer and make it configurable
Testing has shown that the backtrace sometimes does not fit into the 4kB
temporary buffer that is used in NMI context. The warnings are gone
when I double the temporary buffer size.
This patch doubles the buffer size and makes it configurable.
Note that this problem existed even in the x86-specific implementation
that was added by the commit
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Petr Mladek
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42a0bb3f71 |
printk/nmi: generic solution for safe printk in NMI
printk() takes some locks and could not be used a safe way in NMI
context.
The chance of a deadlock is real especially when printing stacks from
all CPUs. This particular problem has been addressed on x86 by the
commit
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Yang Shi
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b8f1a75d61 |
mm: call page_ext_init() after all struct pages are initialized
When DEFERRED_STRUCT_PAGE_INIT is enabled, just a subset of memmap at boot are initialized, then the rest are initialized in parallel by starting one-off "pgdatinitX" kernel thread for each node X. If page_ext_init is called before it, some pages will not have valid extension, this may lead the below kernel oops when booting up kernel: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 PGD 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 11 PID: 106 Comm: pgdatinit1 Not tainted 4.6.0-rc5-next-20160427 #26 Hardware name: Intel Corporation S5520HC/S5520HC, BIOS S5500.86B.01.10.0025.030220091519 03/02/2009 task: ffff88017c080040 ti: ffff88017c084000 task.ti: ffff88017c084000 RIP: 0010:[<ffffffff8118d982>] [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 RSP: 0000:ffff88017c087c48 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000980 RSI: 0000000000000080 RDI: 0000000000660401 RBP: ffff88017c087cd0 R08: 0000000000000401 R09: 0000000000000009 R10: ffff88017c080040 R11: 000000000000000a R12: 0000000000000400 R13: ffffea0019810000 R14: ffffea0019810040 R15: ffff88066cfe6080 FS: 0000000000000000(0000) GS:ffff88066cd40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000002406000 CR4: 00000000000006e0 Call Trace: free_hot_cold_page+0x192/0x1d0 __free_pages+0x5c/0x90 __free_pages_boot_core+0x11a/0x14e deferred_free_range+0x50/0x62 deferred_init_memmap+0x220/0x3c3 kthread+0xf8/0x110 ret_from_fork+0x22/0x40 Code: 49 89 d4 48 c1 e0 06 49 01 c5 e9 de fe ff ff 4c 89 f7 44 89 4d b8 4c 89 45 c0 44 89 5d c8 48 89 4d d0 e8 62 c7 07 00 48 8b 4d d0 <48> 8b 00 44 8b 5d c8 4c 8b 45 c0 44 8b 4d b8 a8 02 0f 84 05 ff RIP [<ffffffff8118d982>] free_pcppages_bulk+0x2d2/0x8d0 RSP <ffff88017c087c48> CR2: 0000000000000000 Move page_ext_init() after page_alloc_init_late() to make sure page extension is setup for all pages. Link: http://lkml.kernel.org/r/1463696006-31360-1-git-send-email-yang.shi@linaro.org Signed-off-by: Yang Shi <yang.shi@linaro.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Thomas Garnier
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c7ce4f60ac |
mm: SLAB freelist randomization
Provides an optional config (CONFIG_SLAB_FREELIST_RANDOM) to randomize the SLAB freelist. The list is randomized during initialization of a new set of pages. The order on different freelist sizes is pre-computed at boot for performance. Each kmem_cache has its own randomized freelist. Before pre-computed lists are available freelists are generated dynamically. This security feature reduces the predictability of the kernel SLAB allocator against heap overflows rendering attacks much less stable. For example this attack against SLUB (also applicable against SLAB) would be affected: https://jon.oberheide.org/blog/2010/09/10/linux-kernel-can-slub-overflow/ Also, since v4.6 the freelist was moved at the end of the SLAB. It means a controllable heap is opened to new attacks not yet publicly discussed. A kernel heap overflow can be transformed to multiple use-after-free. This feature makes this type of attack harder too. To generate entropy, we use get_random_bytes_arch because 0 bits of entropy is available in the boot stage. In the worse case this function will fallback to the get_random_bytes sub API. We also generate a shift random number to shift pre-computed freelist for each new set of pages. The config option name is not specific to the SLAB as this approach will be extended to other allocators like SLUB. Performance results highlighted no major changes: Hackbench (running 90 10 times): Before average: 0.0698 After average: 0.0663 (-5.01%) slab_test 1 run on boot. Difference only seen on the 2048 size test being the worse case scenario covered by freelist randomization. New slab pages are constantly being created on the 10000 allocations. Variance should be mainly due to getting new pages every few allocations. Before: Single thread testing ===================== 1. Kmalloc: Repeatedly allocate then free test 10000 times kmalloc(8) -> 99 cycles kfree -> 112 cycles 10000 times kmalloc(16) -> 109 cycles kfree -> 140 cycles 10000 times kmalloc(32) -> 129 cycles kfree -> 137 cycles 10000 times kmalloc(64) -> 141 cycles kfree -> 141 cycles 10000 times kmalloc(128) -> 152 cycles kfree -> 148 cycles 10000 times kmalloc(256) -> 195 cycles kfree -> 167 cycles 10000 times kmalloc(512) -> 257 cycles kfree -> 199 cycles 10000 times kmalloc(1024) -> 393 cycles kfree -> 251 cycles 10000 times kmalloc(2048) -> 649 cycles kfree -> 228 cycles 10000 times kmalloc(4096) -> 806 cycles kfree -> 370 cycles 10000 times kmalloc(8192) -> 814 cycles kfree -> 411 cycles 10000 times kmalloc(16384) -> 892 cycles kfree -> 455 cycles 2. Kmalloc: alloc/free test 10000 times kmalloc(8)/kfree -> 121 cycles 10000 times kmalloc(16)/kfree -> 121 cycles 10000 times kmalloc(32)/kfree -> 121 cycles 10000 times kmalloc(64)/kfree -> 121 cycles 10000 times kmalloc(128)/kfree -> 121 cycles 10000 times kmalloc(256)/kfree -> 119 cycles 10000 times kmalloc(512)/kfree -> 119 cycles 10000 times kmalloc(1024)/kfree -> 119 cycles 10000 times kmalloc(2048)/kfree -> 119 cycles 10000 times kmalloc(4096)/kfree -> 121 cycles 10000 times kmalloc(8192)/kfree -> 119 cycles 10000 times kmalloc(16384)/kfree -> 119 cycles After: Single thread testing ===================== 1. Kmalloc: Repeatedly allocate then free test 10000 times kmalloc(8) -> 130 cycles kfree -> 86 cycles 10000 times kmalloc(16) -> 118 cycles kfree -> 86 cycles 10000 times kmalloc(32) -> 121 cycles kfree -> 85 cycles 10000 times kmalloc(64) -> 176 cycles kfree -> 102 cycles 10000 times kmalloc(128) -> 178 cycles kfree -> 100 cycles 10000 times kmalloc(256) -> 205 cycles kfree -> 109 cycles 10000 times kmalloc(512) -> 262 cycles kfree -> 136 cycles 10000 times kmalloc(1024) -> 342 cycles kfree -> 157 cycles 10000 times kmalloc(2048) -> 701 cycles kfree -> 238 cycles 10000 times kmalloc(4096) -> 803 cycles kfree -> 364 cycles 10000 times kmalloc(8192) -> 835 cycles kfree -> 404 cycles 10000 times kmalloc(16384) -> 896 cycles kfree -> 441 cycles 2. Kmalloc: alloc/free test 10000 times kmalloc(8)/kfree -> 121 cycles 10000 times kmalloc(16)/kfree -> 121 cycles 10000 times kmalloc(32)/kfree -> 123 cycles 10000 times kmalloc(64)/kfree -> 142 cycles 10000 times kmalloc(128)/kfree -> 121 cycles 10000 times kmalloc(256)/kfree -> 119 cycles 10000 times kmalloc(512)/kfree -> 119 cycles 10000 times kmalloc(1024)/kfree -> 119 cycles 10000 times kmalloc(2048)/kfree -> 119 cycles 10000 times kmalloc(4096)/kfree -> 119 cycles 10000 times kmalloc(8192)/kfree -> 119 cycles 10000 times kmalloc(16384)/kfree -> 119 cycles [akpm@linux-foundation.org: propagate gfp_t into cache_random_seq_create()] Signed-off-by: Thomas Garnier <thgarnie@google.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Greg Thelen <gthelen@google.com> Cc: Laura Abbott <labbott@fedoraproject.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Arnd Bergmann
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877417e6ff |
Kbuild: change CC_OPTIMIZE_FOR_SIZE definition
CC_OPTIMIZE_FOR_SIZE disables the often useful -Wmaybe-unused warning, because that causes a ridiculous amount of false positives when combined with -Os. This means a lot of warnings don't show up in testing by the developers that should see them with an 'allmodconfig' kernel that has CC_OPTIMIZE_FOR_SIZE enabled, but only later in randconfig builds that don't. This changes the Kconfig logic around CC_OPTIMIZE_FOR_SIZE to make it a 'choice' statement defaulting to CC_OPTIMIZE_FOR_PERFORMANCE that gets added for this purpose. The allmodconfig and allyesconfig kernels now default to -O2 with the maybe-unused warning enabled. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Michal Marek <mmarek@suse.com> |
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Andi Kleen
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f76be61755 |
Make CONFIG_FHANDLE default y
Newer Fedora and OpenSUSE didn't boot with my standard configuration. It took me some time to figure out why, in fact I had to write a script to try different config options systematically. The problem is that something (systemd) in dracut depends on CONFIG_FHANDLE, which adds open by file handle syscalls. While it is set in defconfigs it is very easy to miss when updating older configs because it is not default y. Make it default y and also depend on EXPERT, as dracut use is likely widespread. Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Richard Weinberger <richard.weinberger@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Nicolas Pitre
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dbacb0ef67 |
kconfig option for TRIM_UNUSED_KSYMS
The config option to enable it all. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> |
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Linus Torvalds
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6b5f04b6cf |
Merge branch 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
"cgroup changes for v4.6-rc1. No userland visible behavior changes in
this pull request. I'll send out a separate pull request for the
addition of cgroup namespace support.
- The biggest change is the revamping of cgroup core task migration
and controller handling logic. There are quite a few places where
controllers and tasks are manipulated. Previously, many of those
places implemented custom operations for each specific use case
assuming specific starting conditions. While this worked, it makes
the code fragile and difficult to follow.
The bulk of this pull request restructures these operations so that
most related operations are performed through common helpers which
implement recursive (subtrees are always processed consistently)
and idempotent (they make cgroup hierarchy converge to the target
state rather than performing operations assuming specific starting
conditions). This makes the code a lot easier to understand,
verify and extend.
- Implicit controller support is added. This is primarily for using
perf_event on the v2 hierarchy so that perf can match cgroup v2
path without requiring the user to do anything special. The kernel
portion of perf_event changes is acked but userland changes are
still pending review.
- cgroup_no_v1= boot parameter added to ease testing cgroup v2 in
certain environments.
- There is a regression introduced during v4.4 devel cycle where
attempts to migrate zombie tasks can mess up internal object
management. This was fixed earlier this week and included in this
pull request w/ stable cc'd.
- Misc non-critical fixes and improvements"
* 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (44 commits)
cgroup: avoid false positive gcc-6 warning
cgroup: ignore css_sets associated with dead cgroups during migration
Documentation: cgroup v2: Trivial heading correction.
cgroup: implement cgroup_subsys->implicit_on_dfl
cgroup: use css_set->mg_dst_cgrp for the migration target cgroup
cgroup: make cgroup[_taskset]_migrate() take cgroup_root instead of cgroup
cgroup: move migration destination verification out of cgroup_migrate_prepare_dst()
cgroup: fix incorrect destination cgroup in cgroup_update_dfl_csses()
cgroup: Trivial correction to reflect controller.
cgroup: remove stale item in cgroup-v1 document INDEX file.
cgroup: update css iteration in cgroup_update_dfl_csses()
cgroup: allocate 2x cgrp_cset_links when setting up a new root
cgroup: make cgroup_calc_subtree_ss_mask() take @this_ss_mask
cgroup: reimplement rebind_subsystems() using cgroup_apply_control() and friends
cgroup: use cgroup_apply_enable_control() in cgroup creation path
cgroup: combine cgroup_mutex locking and offline css draining
cgroup: factor out cgroup_{apply|finalize}_control() from cgroup_subtree_control_write()
cgroup: introduce cgroup_{save|propagate|restore}_control()
cgroup: make cgroup_drain_offline() and cgroup_apply_control_{disable|enable}() recursive
cgroup: factor out cgroup_apply_control_enable() from cgroup_subtree_control_write()
...
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Linus Torvalds
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bb7aeae3d6 |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris: "There are a bunch of fixes to the TPM, IMA, and Keys code, with minor fixes scattered across the subsystem. IMA now requires signed policy, and that policy is also now measured and appraised" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits) X.509: Make algo identifiers text instead of enum akcipher: Move the RSA DER encoding check to the crypto layer crypto: Add hash param to pkcs1pad sign-file: fix build with CMS support disabled MAINTAINERS: update tpmdd urls MODSIGN: linux/string.h should be #included to get memcpy() certs: Fix misaligned data in extra certificate list X.509: Handle midnight alternative notation in GeneralizedTime X.509: Support leap seconds Handle ISO 8601 leap seconds and encodings of midnight in mktime64() X.509: Fix leap year handling again PKCS#7: fix unitialized boolean 'want' firmware: change kernel read fail to dev_dbg() KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert KEYS: Reserve an extra certificate symbol for inserting without recompiling modsign: hide openssl output in silent builds tpm_tis: fix build warning with tpm_tis_resume ima: require signed IMA policy ima: measure and appraise the IMA policy itself ima: load policy using path ... |
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Linus Torvalds
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271ecc5253 |
Merge branch 'akpm' (patches from Andrew)
Merge first patch-bomb from Andrew Morton: - some misc things - ofs2 updates - about half of MM - checkpatch updates - autofs4 update * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits) autofs4: fix string.h include in auto_dev-ioctl.h autofs4: use pr_xxx() macros directly for logging autofs4: change log print macros to not insert newline autofs4: make autofs log prints consistent autofs4: fix some white space errors autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked() autofs4: fix coding style line length in autofs4_wait() autofs4: fix coding style problem in autofs4_get_set_timeout() autofs4: coding style fixes autofs: show pipe inode in mount options kallsyms: add support for relative offsets in kallsyms address table kallsyms: don't overload absolute symbol type for percpu symbols x86: kallsyms: disable absolute percpu symbols on !SMP checkpatch: fix another left brace warning checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses checkpatch: warn on bare unsigned or signed declarations without int checkpatch: exclude asm volatile from complex macro check mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate() mm: migrate: consolidate mem_cgroup_migrate() calls mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous ... |
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Ard Biesheuvel
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2213e9a66b |
kallsyms: add support for relative offsets in kallsyms address table
Similar to how relative extables are implemented, it is possible to emit the kallsyms table in such a way that it contains offsets relative to some anchor point in the kernel image rather than absolute addresses. On 64-bit architectures, it cuts the size of the kallsyms address table in half, since offsets between kernel symbols can typically be expressed in 32 bits. This saves several hundreds of kilobytes of permanent .rodata on average. In addition, the kallsyms address table is no longer subject to dynamic relocation when CONFIG_RELOCATABLE is in effect, so the relocation work done after decompression now doesn't have to do relocation updates for all these values. This saves up to 24 bytes (i.e., the size of a ELF64 RELA relocation table entry) per value, which easily adds up to a couple of megabytes of uncompressed __init data on ppc64 or arm64. Even if these relocation entries typically compress well, the combined size reduction of 2.8 MB uncompressed for a ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500 KB space saving in the compressed image. Since it is useful for some architectures (like x86) to retain the ability to emit absolute values as well, this patch also adds support for capturing both absolute and relative values when KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu addresses as positive 32-bit values, and addresses relative to the lowest encountered relative symbol as negative values, which are subtracted from the runtime address of this base symbol to produce the actual address. Support for the above is enabled by default for all architectures except IA-64 and Tile-GX, whose symbols are too far apart to capture in this manner. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Kees Cook <keescook@chromium.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Ard Biesheuvel
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4d5d5664c9 |
x86: kallsyms: disable absolute percpu symbols on !SMP
scripts/kallsyms.c has a special --absolute-percpu command line option which deals with the zero based per cpu offsets that are used when building for SMP on x86_64. This means that the option should only be passed in that case, so add a Kconfig symbol with the correct predicate, and use that instead. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Kees Cook <keescook@chromium.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Geliang Tang
|
e6fd1fb3b5 |
init/main.c: use list_for_each_entry()
Use list_for_each_entry() instead of list_for_each() to simplify the code. Signed-off-by: Geliang Tang <geliangtang@163.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Linus Torvalds
|
710d60cbf1 |
Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull cpu hotplug updates from Thomas Gleixner:
"This is the first part of the ongoing cpu hotplug rework:
- Initial implementation of the state machine
- Runs all online and prepare down callbacks on the plugged cpu and
not on some random processor
- Replaces busy loop waiting with completions
- Adds tracepoints so the states can be followed"
More detailed commentary on this work from an earlier email:
"What's wrong with the current cpu hotplug infrastructure?
- Asymmetry
The hotplug notifier mechanism is asymmetric versus the bringup and
teardown. This is mostly caused by the notifier mechanism.
- Largely undocumented dependencies
While some notifiers use explicitely defined notifier priorities,
we have quite some notifiers which use numerical priorities to
express dependencies without any documentation why.
- Control processor driven
Most of the bringup/teardown of a cpu is driven by a control
processor. While it is understandable, that preperatory steps,
like idle thread creation, memory allocation for and initialization
of essential facilities needs to be done before a cpu can boot,
there is no reason why everything else must run on a control
processor. Before this patch series, bringup looks like this:
Control CPU Booting CPU
do preparatory steps
kick cpu into life
do low level init
sync with booting cpu sync with control cpu
bring the rest up
- All or nothing approach
There is no way to do partial bringups. That's something which is
really desired because we waste e.g. at boot substantial amount of
time just busy waiting that the cpu comes to life. That's stupid
as we could very well do preparatory steps and the initial IPI for
other cpus and then go back and do the necessary low level
synchronization with the freshly booted cpu.
- Minimal debuggability
Due to the notifier based design, it's impossible to switch between
two stages of the bringup/teardown back and forth in order to test
the correctness. So in many hotplug notifiers the cancel
mechanisms are either not existant or completely untested.
- Notifier [un]registering is tedious
To [un]register notifiers we need to protect against hotplug at
every callsite. There is no mechanism that bringup/teardown
callbacks are issued on the online cpus, so every caller needs to
do it itself. That also includes error rollback.
What's the new design?
The base of the new design is a symmetric state machine, where both
the control processor and the booting/dying cpu execute a well
defined set of states. Each state is symmetric in the end, except
for some well defined exceptions, and the bringup/teardown can be
stopped and reversed at almost all states.
So the bringup of a cpu will look like this in the future:
Control CPU Booting CPU
do preparatory steps
kick cpu into life
do low level init
sync with booting cpu sync with control cpu
bring itself up
The synchronization step does not require the control cpu to wait.
That mechanism can be done asynchronously via a worker or some
other mechanism.
The teardown can be made very similar, so that the dying cpu cleans
up and brings itself down. Cleanups which need to be done after
the cpu is gone, can be scheduled asynchronously as well.
There is a long way to this, as we need to refactor the notion when a
cpu is available. Today we set the cpu online right after it comes
out of the low level bringup, which is not really correct.
The proper mechanism is to set it to available, i.e. cpu local
threads, like softirqd, hotplug thread etc. can be scheduled on that
cpu, and once it finished all booting steps, it's set to online, so
general workloads can be scheduled on it. The reverse happens on
teardown. First thing to do is to forbid scheduling of general
workloads, then teardown all the per cpu resources and finally shut it
off completely.
This patch series implements the basic infrastructure for this at the
core level. This includes the following:
- Basic state machine implementation with well defined states, so
ordering and prioritization can be expressed.
- Interfaces to [un]register state callbacks
This invokes the bringup/teardown callback on all online cpus with
the proper protection in place and [un]installs the callbacks in
the state machine array.
For callbacks which have no particular ordering requirement we have
a dynamic state space, so that drivers don't have to register an
explicit hotplug state.
If a callback fails, the code automatically does a rollback to the
previous state.
- Sysfs interface to drive the state machine to a particular step.
This is only partially functional today. Full functionality and
therefor testability will be achieved once we converted all
existing hotplug notifiers over to the new scheme.
- Run all CPU_ONLINE/DOWN_PREPARE notifiers on the booting/dying
processor:
Control CPU Booting CPU
do preparatory steps
kick cpu into life
do low level init
sync with booting cpu sync with control cpu
wait for boot
bring itself up
Signal completion to control cpu
In a previous step of this work we've done a full tree mechanical
conversion of all hotplug notifiers to the new scheme. The balance
is a net removal of about 4000 lines of code.
This is not included in this series, as we decided to take a
different approach. Instead of mechanically converting everything
over, we will do a proper overhaul of the usage sites one by one so
they nicely fit into the symmetric callback scheme.
I decided to do that after I looked at the ugliness of some of the
converted sites and figured out that their hotplug mechanism is
completely buggered anyway. So there is no point to do a
mechanical conversion first as we need to go through the usage
sites one by one again in order to achieve a full symmetric and
testable behaviour"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
cpu/hotplug: Document states better
cpu/hotplug: Fix smpboot thread ordering
cpu/hotplug: Remove redundant state check
cpu/hotplug: Plug death reporting race
rcu: Make CPU_DYING_IDLE an explicit call
cpu/hotplug: Make wait for dead cpu completion based
cpu/hotplug: Let upcoming cpu bring itself fully up
arch/hotplug: Call into idle with a proper state
cpu/hotplug: Move online calls to hotplugged cpu
cpu/hotplug: Create hotplug threads
cpu/hotplug: Split out the state walk into functions
cpu/hotplug: Unpark smpboot threads from the state machine
cpu/hotplug: Move scheduler cpu_online notifier to hotplug core
cpu/hotplug: Implement setup/removal interface
cpu/hotplug: Make target state writeable
cpu/hotplug: Add sysfs state interface
cpu/hotplug: Hand in target state to _cpu_up/down
cpu/hotplug: Convert the hotplugged cpu work to a state machine
cpu/hotplug: Convert to a state machine for the control processor
cpu/hotplug: Add tracepoints
...
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Linus Torvalds
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d09e356ad0 |
Merge branch 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull read-only kernel memory updates from Ingo Molnar:
"This tree adds two (security related) enhancements to the kernel's
handling of read-only kernel memory:
- extend read-only kernel memory to a new class of formerly writable
kernel data: 'post-init read-only memory' via the __ro_after_init
attribute, and mark the ARM and x86 vDSO as such read-only memory.
This kind of attribute can be used for data that requires a once
per bootup initialization sequence, but is otherwise never modified
after that point.
This feature was based on the work by PaX Team and Brad Spengler.
(by Kees Cook, the ARM vDSO bits by David Brown.)
- make CONFIG_DEBUG_RODATA always enabled on x86 and remove the
Kconfig option. This simplifies the kernel and also signals that
read-only memory is the default model and a first-class citizen.
(Kees Cook)"
* 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ARM/vdso: Mark the vDSO code read-only after init
x86/vdso: Mark the vDSO code read-only after init
lkdtm: Verify that '__ro_after_init' works correctly
arch: Introduce post-init read-only memory
x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option
mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
asm-generic: Consolidate mark_rodata_ro()
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Parav Pandit
|
6cc578df40 |
cgroup: Trivial correction to reflect controller.
Trivial correction in menuconfig help to reflect PIDs as controller instead of subsystem to align to rest of the text and documentation. Signed-off-by: Parav Pandit <pandit.parav@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
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David Howells
|
d43de6c780 |
akcipher: Move the RSA DER encoding check to the crypto layer
Move the RSA EMSA-PKCS1-v1_5 encoding from the asymmetric-key public_key
subtype to the rsa crypto module's pkcs1pad template. This means that the
public_key subtype no longer has any dependencies on public key type.
To make this work, the following changes have been made:
(1) The rsa pkcs1pad template is now used for RSA keys. This strips off the
padding and returns just the message hash.
(2) In a previous patch, the pkcs1pad template gained an optional second
parameter that, if given, specifies the hash used. We now give this,
and pkcs1pad checks the encoded message E(M) for the EMSA-PKCS1-v1_5
encoding and verifies that the correct digest OID is present.
(3) The crypto driver in crypto/asymmetric_keys/rsa.c is now reduced to
something that doesn't care about what the encryption actually does
and and has been merged into public_key.c.
(4) CONFIG_PUBLIC_KEY_ALGO_RSA is gone. Module signing must set
CONFIG_CRYPTO_RSA=y instead.
Thoughts:
(*) Should the encoding style (eg. raw, EMSA-PKCS1-v1_5) also be passed to
the padding template? Should there be multiple padding templates
registered that share most of the code?
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
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Thomas Gleixner
|
931ef16330 |
cpu/hotplug: Unpark smpboot threads from the state machine
Handle the smpboot threads in the state machine. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Rik van Riel <riel@redhat.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20160226182341.295777684@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
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Thomas Gleixner
|
cff7d378d3 |
cpu/hotplug: Convert to a state machine for the control processor
Move the split out steps into a callback array and let the cpu_up/down code iterate through the array functions. For now most of the callbacks are asymmetric to resemble the current hotplug maze. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Rik van Riel <riel@redhat.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20160226182340.671816690@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
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Kees Cook
|
d2aa1acad2 |
mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
It may be useful to debug writes to the readonly sections of memory, so provide a cmdline "rodata=off" to allow for this. This can be expanded in the future to support "log" and "write" modes, but that will need to be architecture-specific. This also makes KDB software breakpoints more usable, as read-only mappings can now be disabled on any kernel. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Brown <david.brown@linaro.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Emese Revfy <re.emese@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathias Krause <minipli@googlemail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: PaX Team <pageexec@freemail.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-hardening@lists.openwall.com Cc: linux-arch <linux-arch@vger.kernel.org> Link: http://lkml.kernel.org/r/1455748879-21872-3-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Andrey Ryabinin
|
06bea3dbfe |
locking/lockdep: Eliminate lockdep_init()
Lockdep is initialized at compile time now. Get rid of lockdep_init(). Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Krinkin <krinkin.m.u@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Cc: mm-commits@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Johannes Weiner
|
d886f4e483 |
mm: memcontrol: rein in the CONFIG space madness
What CONFIG_INET and CONFIG_LEGACY_KMEM guard inside the memory controller code is insignificant, having these conditionals is not worth the complication and fragility that comes with them. [akpm@linux-foundation.org: rework mem_cgroup_css_free() statement ordering] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
|
489c2a20a4 |
mm: memcontrol: introduce CONFIG_MEMCG_LEGACY_KMEM
Let the user know that CONFIG_MEMCG_KMEM does not apply to the cgroup2 interface. This also makes legacy-only code sections stand out better. [arnd@arndb.de: mm: memcontrol: only manage socket pressure for CONFIG_INET] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Tejun Heo <tj@kernel.org> Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Yaowei Bai
|
f057f3b226 |
init/do_mounts: initrd_load() can be boolean
Make initrd_load() return bool due to this particular function only using either one or zero as its return value. No functional change. Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Yaowei Bai
|
31c025b5fe |
init/main.c: obsolete_checksetup can be boolean
Make obsolete_checksetup() return bool due to this particular function only using either one or zero as its return value. No functional change. Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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|
Linus Torvalds
|
2d663b5581 |
Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit updates from Paul Moore: "Seven audit patches for 4.5, all very minor despite the diffstat. The diffstat churn for linux/audit.h can be attributed to needing to reshuffle the linux/audit.h header to fix the seccomp auditing issue (see the commit description for details). Besides the seccomp/audit fix, most of the fixes are around trying to improve the connection with the audit daemon and a Kconfig simplification. Nothing crazy, and everything passes our little audit-testsuite" * 'upstream' of git://git.infradead.org/users/pcmoore/audit: audit: always enable syscall auditing when supported and audit is enabled audit: force seccomp event logging to honor the audit_enabled flag audit: Delete unnecessary checks before two function calls audit: wake up threads if queue switched from limited to unlimited audit: include auditd's threads in audit_log_start() wait exception audit: remove audit_backlog_wait_overflow audit: don't needlessly reset valid wait time |
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Linus Torvalds
|
0cbeafb245 |
Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:
- more MM stuff:
- Kirill's page-flags rework
- Kirill's now-allegedly-fixed THP rework
- MADV_FREE implementation
- DAX feature work (msync/fsync). This isn't quite complete but DAX
is new and it's good enough and the guys have a handle on what
needs to be done - I expect this to be wrapped in the next week or
two.
- some vsprintf maintenance work
- various other misc bits
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (145 commits)
printk: change recursion_bug type to bool
lib/vsprintf: factor out %pN[F] handler as netdev_bits()
lib/vsprintf: refactor duplicate code to special_hex_number()
printk-formats.txt: remove unimplemented %pT
printk: help pr_debug and pr_devel to optimize out arguments
lib/test_printf.c: test dentry printing
lib/test_printf.c: add test for large bitmaps
lib/test_printf.c: account for kvasprintf tests
lib/test_printf.c: add a few number() tests
lib/test_printf.c: test precision quirks
lib/test_printf.c: check for out-of-bound writes
lib/test_printf.c: don't BUG
lib/kasprintf.c: add sanity check to kvasprintf
lib/vsprintf.c: warn about too large precisions and field widths
lib/vsprintf.c: help gcc make number() smaller
lib/vsprintf.c: expand field_width to 24 bits
lib/vsprintf.c: eliminate potential race in string()
lib/vsprintf.c: move string() below widen_string()
lib/vsprintf.c: pull out padding code from dentry_name()
printk: do cond_resched() between lines while outputting to consoles
...
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Linus Torvalds
|
e535d74bc5 |
A relatively boring cycle in the docs tree. There's a few kernel-doc
fixes and various document tweaks. One patch reaches out of the documentation subtree to fix a comment in init/do_mounts_rd.c. There didn't seem to be anybody more appropriate to take that one, so I accepted it. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJWmmJ8AAoJEI3ONVYwIuV6uqwP/0mnqdxVWo47ohaYJP7q0Soh ovJAbfttxKnkmOdGbWcNIJtTiw+MpdF805CYR+2treE0zvEEDodg7BhkDnmKZJ9n F1r53JrIj769E1c5ETmWTHcBt3jjtKyQIbBmDr4YTgX91dlKF28o1bMmyDECWIcT PktTlPUidDtffKMn3klh6baPCMrTpLJ8aLshBzUrQhrQY8lxcZKAU+98vtFzYofG LXCSulMYXumb7XBxErTLQZhmJslD4gaDMh2xkov6ALS8XNHnfoUIFRbArAllNfTf LQGJ6Q5qnn58UWi9F/vgDqx7+d1KIPUjBxJR9wfa0w9ggQhA9ly2BSN/fllbiSbp yIi1JS4hwBe8H/h577BNC3xjmgVN7mazZsXlS+fg3G16gpv4JdWeRY4efjosFIzQ EIJxB8qAovUNqw4s1mzRIJ5B9L7PEK27O6z8N27Fiw4EigtMTFAOC2/GD3ELx4iJ p1doiSr+wjfDcFd8kdIUiDKGrTSTXwNy3hUfrhzQyaEjDTJnx3+1+ono1orSazPO Fr2RSsC5VzX4IYSuxTMvFSKjN1Iiu8xqwq3IdclHXrBhRvwOF2wpjjQ5Guf0lHBJ FLBahSjZqt01kmwFykxoHps+VeSwpoEen6rClBQolfmtYVDTvgRNN46AxK9jZ8T4 jZmCNNs/mYzrqo/RTnmw =u38W -----END PGP SIGNATURE----- Merge tag 'docs-4.5' of git://git.lwn.net/linux Pull documentation updates from Jon Corbet: "A relatively boring cycle in the docs tree. There's a few kernel-doc fixes and various document tweaks. One patch reaches out of the documentation subtree to fix a comment in init/do_mounts_rd.c. There didn't seem to be anybody more appropriate to take that one, so I accepted it" * tag 'docs-4.5' of git://git.lwn.net/linux: (29 commits) thermal: add description for integral_cutoff unit Documentation: update libhugetlbfs site url Documentation: Explain pci=conf1,conf2 more verbosely DMA-API: fix confusing sentence in Documentation/DMA-API.txt Documentation: translations: update linux cross reference link Documentation: fix typo in CodingStyle init, Documentation: Remove ramdisk_blocksize mentions Documentation-getdelays: Apply a recommendation from "checkpatch.pl" in main() Documentation: HOWTO: update versions from 3.x to 4.x Documentation: remove outdated references from translations Doc: treewide: Fix grammar "a" to "an" Documentation: cpu-hotplug: Fix sysfs mount instructions can-doc: Add hint about getting timestamps Fix CFQ I/O scheduler parameter name in documentation Documentation: arm: remove dead links from Marvell Berlin docs Documentation: HOWTO: update code cross reference link Doc: Docbook/iio: Fix typo in iio.tmpl DocBook: make index.html generation less verbose by default DocBook: Cleanup: remove an unused $(call) line DocBook: Add a help message for DOCBOOKS env var ... |
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Riku Voipio
|
b2113a417c |
uselib: default depending if libc5 was used
uselib hasn't been used since libc5; glibc does not use it. Deprecate uselib a bit more, by making the default y only if libc5 was widely used on the plaform. This makes arm64 kernel built with defconfig slightly smaller bloat-o-meter: add/remove: 0/3 grow/shrink: 0/2 up/down: 0/-1390 (-1390) function old new delta kernel_config_data 18164 18162 -2 uselib_flags 20 - -20 padzero 216 192 -24 sys_uselib 380 - -380 load_elf_library 964 - -964 Signed-off-by: Riku Voipio <riku.voipio@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Paul Moore
|
cb74ed278f |
audit: always enable syscall auditing when supported and audit is enabled
To the best of our knowledge, everyone who enables audit at compile time also enables syscall auditing; this patch simplifies the Kconfig menus by removing the option to disable syscall auditing when audit is selected and the target arch supports it. Signed-off-by: Paul Moore <pmoore@redhat.com> |
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Linus Torvalds
|
34a9304a96 |
Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo: - cgroup v2 interface is now official. It's no longer hidden behind a devel flag and can be mounted using the new cgroup2 fs type. Unfortunately, cpu v2 interface hasn't made it yet due to the discussion around in-process hierarchical resource distribution and only memory and io controllers can be used on the v2 interface at the moment. - The existing documentation which has always been a bit of mess is relocated under Documentation/cgroup-v1/. Documentation/cgroup-v2.txt is added as the authoritative documentation for the v2 interface. - Some features are added through for-4.5-ancestor-test branch to enable netfilter xt_cgroup match to use cgroup v2 paths. The actual netfilter changes will be merged through the net tree which pulled in the said branch. - Various cleanups * 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: rename cgroup documentations cgroup: fix a typo. cgroup: Remove resource_counter.txt in Documentation/cgroup-legacy/00-INDEX. cgroup: demote subsystem init messages to KERN_DEBUG cgroup: Fix uninitialized variable warning cgroup: put controller Kconfig options in meaningful order cgroup: clean up the kernel configuration menu nomenclature cgroup_pids: fix a typo. Subject: cgroup: Fix incomplete dd command in blkio documentation cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends cpuset: Replace all instances of time_t with time64_t cgroup: replace unified-hierarchy.txt with a proper cgroup v2 documentation cgroup: rename Documentation/cgroups/ to Documentation/cgroup-legacy/ cgroup: replace __DEVEL__sane_behavior with cgroup2 fs type |
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Ingo Molnar
|
3104fb3dd4 |
Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney: - Adding transitivity uniformly to rcu_node structure ->lock acquisitions. (This is implemented by the first two commits on top of v4.4-rc2 due to the pervasive nature of this change.) - Documentation updates, including RCU requirements. - Expedited grace-period changes. - Miscellaneous fixes. - Linked-list fixes, courtesy of KTSAN. - Torture-test updates. - Late-breaking fix to sysrq-generated crash. Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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Robert Elliott
|
b03539665d |
init, Documentation: Remove ramdisk_blocksize mentions
The brd driver has never supported the ramdisk_blocksize kernel parameter that was in the rd driver it replaced, so remove mention of this parameter from comments and Documentation. Commit |
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Johannes Weiner
|
6bf024e693 |
cgroup: put controller Kconfig options in meaningful order
To make it easier to quickly find what's needed list the basic resource controllers of cgroup2 first - io, memory, cpu - while pushing the more exotic and/or legacy controllers to the bottom. tj: Removed spurious "&& CGROUPS" from CGROUP_PERF as suggested by Li. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
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Johannes Weiner
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a0166ec4b0 |
cgroup: clean up the kernel configuration menu nomenclature
The config options for the different cgroup controllers use various terms: resource controller, cgroup subsystem, etc. Simplify this to "controller", which is clear enough in the cgroup context. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Tejun Heo <tj@kernel.org> |
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Chris Wilson
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86fffe4a61 |
kernel: remove stop_machine() Kconfig dependency
Currently the full stop_machine() routine is only enabled on SMP if
module unloading is enabled, or if the CPUs are hotpluggable. This
leads to configurations where stop_machine() is broken as it will then
only run the callback on the local CPU with irqs disabled, and not stop
the other CPUs or run the callback on them.
For example, this breaks MTRR setup on x86 in certain configs since
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Paul E. McKenney
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967dcb8fe6 |
rcu: Wire up rcu_end_inkernel_boot()
This commit adds the invocation of rcu_end_inkernel_boot() just before init is invoked. This allows the CONFIG_RCU_EXPEDITE_BOOT Kconfig option to do something useful and prepares for the upcoming rcupdate.rcu_normal_after_boot kernel parameter. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
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Mathieu Desnoyers
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5b25b13ab0 |
sys_membarrier(): system-wide memory barrier (generic, x86)
Here is an implementation of a new system call, sys_membarrier(), which executes a memory barrier on all threads running on the system. It is implemented by calling synchronize_sched(). It can be used to distribute the cost of user-space memory barriers asymmetrically by transforming pairs of memory barriers into pairs consisting of sys_membarrier() and a compiler barrier. For synchronization primitives that distinguish between read-side and write-side (e.g. userspace RCU [1], rwlocks), the read-side can be accelerated significantly by moving the bulk of the memory barrier overhead to the write-side. The existing applications of which I am aware that would be improved by this system call are as follows: * Through Userspace RCU library (http://urcu.so) - DNS server (Knot DNS) https://www.knot-dns.cz/ - Network sniffer (http://netsniff-ng.org/) - Distributed object storage (https://sheepdog.github.io/sheepdog/) - User-space tracing (http://lttng.org) - Network storage system (https://www.gluster.org/) - Virtual routers (https://events.linuxfoundation.org/sites/events/files/slides/DPDK_RCU_0MQ.pdf) - Financial software (https://lkml.org/lkml/2015/3/23/189) Those projects use RCU in userspace to increase read-side speed and scalability compared to locking. Especially in the case of RCU used by libraries, sys_membarrier can speed up the read-side by moving the bulk of the memory barrier cost to synchronize_rcu(). * Direct users of sys_membarrier - core dotnet garbage collector (https://github.com/dotnet/coreclr/issues/198) Microsoft core dotnet GC developers are planning to use the mprotect() side-effect of issuing memory barriers through IPIs as a way to implement Windows FlushProcessWriteBuffers() on Linux. They are referring to sys_membarrier in their github thread, specifically stating that sys_membarrier() is what they are looking for. To explain the benefit of this scheme, let's introduce two example threads: Thread A (non-frequent, e.g. executing liburcu synchronize_rcu()) Thread B (frequent, e.g. executing liburcu rcu_read_lock()/rcu_read_unlock()) In a scheme where all smp_mb() in thread A are ordering memory accesses with respect to smp_mb() present in Thread B, we can change each smp_mb() within Thread A into calls to sys_membarrier() and each smp_mb() within Thread B into compiler barriers "barrier()". Before the change, we had, for each smp_mb() pairs: Thread A Thread B previous mem accesses previous mem accesses smp_mb() smp_mb() following mem accesses following mem accesses After the change, these pairs become: Thread A Thread B prev mem accesses prev mem accesses sys_membarrier() barrier() follow mem accesses follow mem accesses As we can see, there are two possible scenarios: either Thread B memory accesses do not happen concurrently with Thread A accesses (1), or they do (2). 1) Non-concurrent Thread A vs Thread B accesses: Thread A Thread B prev mem accesses sys_membarrier() follow mem accesses prev mem accesses barrier() follow mem accesses In this case, thread B accesses will be weakly ordered. This is OK, because at that point, thread A is not particularly interested in ordering them with respect to its own accesses. 2) Concurrent Thread A vs Thread B accesses Thread A Thread B prev mem accesses prev mem accesses sys_membarrier() barrier() follow mem accesses follow mem accesses In this case, thread B accesses, which are ensured to be in program order thanks to the compiler barrier, will be "upgraded" to full smp_mb() by synchronize_sched(). * Benchmarks On Intel Xeon E5405 (8 cores) (one thread is calling sys_membarrier, the other 7 threads are busy looping) 1000 non-expedited sys_membarrier calls in 33s =3D 33 milliseconds/call. * User-space user of this system call: Userspace RCU library Both the signal-based and the sys_membarrier userspace RCU schemes permit us to remove the memory barrier from the userspace RCU rcu_read_lock() and rcu_read_unlock() primitives, thus significantly accelerating them. These memory barriers are replaced by compiler barriers on the read-side, and all matching memory barriers on the write-side are turned into an invocation of a memory barrier on all active threads in the process. By letting the kernel perform this synchronization rather than dumbly sending a signal to every process threads (as we currently do), we diminish the number of unnecessary wake ups and only issue the memory barriers on active threads. Non-running threads do not need to execute such barrier anyway, because these are implied by the scheduler context switches. Results in liburcu: Operations in 10s, 6 readers, 2 writers: memory barriers in reader: 1701557485 reads, 2202847 writes signal-based scheme: 9830061167 reads, 6700 writes sys_membarrier: 9952759104 reads, 425 writes sys_membarrier (dyn. check): 7970328887 reads, 425 writes The dynamic sys_membarrier availability check adds some overhead to the read-side compared to the signal-based scheme, but besides that, sys_membarrier slightly outperforms the signal-based scheme. However, this non-expedited sys_membarrier implementation has a much slower grace period than signal and memory barrier schemes. Besides diminishing the number of wake-ups, one major advantage of the membarrier system call over the signal-based scheme is that it does not need to reserve a signal. This plays much more nicely with libraries, and with processes injected into for tracing purposes, for which we cannot expect that signals will be unused by the application. An expedited version of this system call can be added later on to speed up the grace period. Its implementation will likely depend on reading the cpu_curr()->mm without holding each CPU's rq lock. This patch adds the system call to x86 and to asm-generic. [1] http://urcu.so membarrier(2) man page: MEMBARRIER(2) Linux Programmer's Manual MEMBARRIER(2) NAME membarrier - issue memory barriers on a set of threads SYNOPSIS #include <linux/membarrier.h> int membarrier(int cmd, int flags); DESCRIPTION The cmd argument is one of the following: MEMBARRIER_CMD_QUERY Query the set of supported commands. It returns a bitmask of supported commands. MEMBARRIER_CMD_SHARED Execute a memory barrier on all threads running on the system. Upon return from system call, the caller thread is ensured that all running threads have passed through a state where all memory accesses to user-space addresses match program order between entry to and return from the system call (non-running threads are de facto in such a state). This covers threads from all pro=E2=80=90 cesses running on the system. This command returns 0. The flags argument needs to be 0. For future extensions. All memory accesses performed in program order from each targeted thread is guaranteed to be ordered with respect to sys_membarrier(). If we use the semantic "barrier()" to represent a compiler barrier forcing memory accesses to be performed in program order across the barrier, and smp_mb() to represent explicit memory barriers forcing full memory ordering across the barrier, we have the following ordering table for each pair of barrier(), sys_membarrier() and smp_mb(): The pair ordering is detailed as (O: ordered, X: not ordered): barrier() smp_mb() sys_membarrier() barrier() X X O smp_mb() X O O sys_membarrier() O O O RETURN VALUE On success, these system calls return zero. On error, -1 is returned, and errno is set appropriately. For a given command, with flags argument set to 0, this system call is guaranteed to always return the same value until reboot. ERRORS ENOSYS System call is not implemented. EINVAL Invalid arguments. Linux 2015-04-15 MEMBARRIER(2) Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nicholas Miell <nmiell@comcast.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Pranith Kumar <bobby.prani@gmail.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Dave Young
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2965faa5e0 |
kexec: split kexec_load syscall from kexec core code
There are two kexec load syscalls, kexec_load another and kexec_file_load. kexec_file_load has been splited as kernel/kexec_file.c. In this patch I split kexec_load syscall code to kernel/kexec.c. And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and use kexec_file_load only, or vice verse. The original requirement is from Ted Ts'o, he want kexec kernel signature being checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use kexec_load syscall can bypass the checking. Vivek Goyal proposed to create a common kconfig option so user can compile in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects KEXEC_CORE so that old config files still work. Because there's general code need CONFIG_KEXEC_CORE, so I updated all the architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects KEXEC_CORE in arch Kconfig. Also updated general kernel code with to kexec_load syscall. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Petr Tesarik <ptesarik@suse.cz> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Josh Boyer <jwboyer@fedoraproject.org> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Frederic Weisbecker
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90f023030e |
kmod: use system_unbound_wq instead of khelper
We need to launch the usermodehelper kernel threads with the widest affinity and this is partly why we use khelper. This workqueue has unbound properties and thus a wide affinity inherited by all its children. Now khelper also has special properties that we aren't much interested in: ordered and singlethread. There is really no need about ordering as all we do is creating kernel threads. This can be done concurrently. And singlethread is a useless limitation as well. The workqueue engine already proposes generic unbound workqueues that don't share these useless properties and handle well parallel jobs. The only worrysome specific is their affinity to the node of the current CPU. It's fine for creating the usermodehelper kernel threads but those inherit this affinity for longer jobs such as requesting modules. This patch proposes to use these node affine unbound workqueues assuming that a node is sufficient to handle several parallel usermodehelper requests. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Linus Torvalds
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b793c005ce |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"Highlights:
- PKCS#7 support added to support signed kexec, also utilized for
module signing. See comments in
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Linus Torvalds
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7d9071a095 |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
"In this one:
- d_move fixes (Eric Biederman)
- UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
handling ought to be fixed)
- switch of sb_writers to percpu rwsem (Oleg Nesterov)
- superblock scalability (Josef Bacik and Dave Chinner)
- swapon(2) race fix (Hugh Dickins)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
vfs: Test for and handle paths that are unreachable from their mnt_root
dcache: Reduce the scope of i_lock in d_splice_alias
dcache: Handle escaped paths in prepend_path
mm: fix potential data race in SyS_swapon
inode: don't softlockup when evicting inodes
inode: rename i_wb_list to i_io_list
sync: serialise per-superblock sync operations
inode: convert inode_sb_list_lock to per-sb
inode: add hlist_fake to avoid the inode hash lock in evict
writeback: plug writeback at a high level
change sb_writers to use percpu_rw_semaphore
shift percpu_counter_destroy() into destroy_super_work()
percpu-rwsem: kill CONFIG_PERCPU_RWSEM
percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
percpu-rwsem: introduce percpu_down_read_trylock()
document rwsem_release() in sb_wait_write()
fix the broken lockdep logic in __sb_start_write()
introduce __sb_writers_{acquired,release}() helpers
ufs_inode_get{frag,block}(): get rid of 'phys' argument
ufs_getfrag_block(): tidy up a bit
...
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Linus Torvalds
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6c0f568e84 |
Merge branch 'akpm' (patches from Andrew)
Merge patch-bomb from Andrew Morton: - a few misc things - Andy's "ambient capabilities" - fs/nofity updates - the ocfs2 queue - kernel/watchdog.c updates and feature work. - some of MM. Includes Andrea's userfaultfd feature. [ Hadn't noticed that userfaultfd was 'default y' when applying the patches, so that got fixed in this merge instead. We do _not_ mark new features that nobody uses yet 'default y' - Linus ] * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) mm/hugetlb.c: make vma_has_reserves() return bool mm/madvise.c: make madvise_behaviour_valid() return bool mm/memory.c: make tlb_next_batch() return bool mm/dmapool.c: change is_page_busy() return from int to bool mm: remove struct node_active_region mremap: simplify the "overlap" check in mremap_to() mremap: don't do uneccesary checks if new_len == old_len mremap: don't do mm_populate(new_addr) on failure mm: move ->mremap() from file_operations to vm_operations_struct mremap: don't leak new_vma if f_op->mremap() fails mm/hugetlb.c: make vma_shareable() return bool mm: make GUP handle pfn mapping unless FOLL_GET is requested mm: fix status code which move_pages() returns for zero page mm: memcontrol: bring back the VM_BUG_ON() in mem_cgroup_swapout() genalloc: add support of multiple gen_pools per device genalloc: add name arg to gen_pool_get() and devm_gen_pool_create() mm/memblock: WARN_ON when nid differs from overlap region Documentation/features/vm: add feature description and arch support status for batched TLB flush after unmap mm: defer flush of writable TLB entries mm: send one IPI per CPU to TLB flush all entries after unmapping pages ... |
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Mel Gorman
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72b252aed5 |
mm: send one IPI per CPU to TLB flush all entries after unmapping pages
An IPI is sent to flush remote TLBs when a page is unmapped that was
potentially accesssed by other CPUs. There are many circumstances where
this happens but the obvious one is kswapd reclaiming pages belonging to a
running process as kswapd and the task are likely running on separate
CPUs.
On small machines, this is not a significant problem but as machine gets
larger with more cores and more memory, the cost of these IPIs can be
high. This patch uses a simple structure that tracks CPUs that
potentially have TLB entries for pages being unmapped. When the unmapping
is complete, the full TLB is flushed on the assumption that a refill cost
is lower than flushing individual entries.
Architectures wishing to do this must give the following guarantee.
If a clean page is unmapped and not immediately flushed, the
architecture must guarantee that a write to that linear address
from a CPU with a cached TLB entry will trap a page fault.
This is essentially what the kernel already depends on but the window is
much larger with this patch applied and is worth highlighting. The
architecture should consider whether the cost of the full TLB flush is
higher than sending an IPI to flush each individual entry. An additional
architecture helper called flush_tlb_local is required. It's a trivial
wrapper with some accounting in the x86 case.
The impact of this patch depends on the workload as measuring any benefit
requires both mapped pages co-located on the LRU and memory pressure. The
case with the biggest impact is multiple processes reading mapped pages
taken from the vm-scalability test suite. The test case uses NR_CPU
readers of mapped files that consume 10*RAM.
Linear mapped reader on a 4-node machine with 64G RAM and 48 CPUs
4.2.0-rc1 4.2.0-rc1
vanilla flushfull-v7
Ops lru-file-mmap-read-elapsed 159.62 ( 0.00%) 120.68 ( 24.40%)
Ops lru-file-mmap-read-time_range 30.59 ( 0.00%) 2.80 ( 90.85%)
Ops lru-file-mmap-read-time_stddv 6.70 ( 0.00%) 0.64 ( 90.38%)
4.2.0-rc1 4.2.0-rc1
vanilla flushfull-v7
User 581.00 611.43
System 5804.93 4111.76
Elapsed 161.03 122.12
This is showing that the readers completed 24.40% faster with 29% less
system CPU time. From vmstats, it is known that the vanilla kernel was
interrupted roughly 900K times per second during the steady phase of the
test and the patched kernel was interrupts 180K times per second.
The impact is lower on a single socket machine.
4.2.0-rc1 4.2.0-rc1
vanilla flushfull-v7
Ops lru-file-mmap-read-elapsed 25.33 ( 0.00%) 20.38 ( 19.54%)
Ops lru-file-mmap-read-time_range 0.91 ( 0.00%) 1.44 (-58.24%)
Ops lru-file-mmap-read-time_stddv 0.28 ( 0.00%) 0.47 (-65.34%)
4.2.0-rc1 4.2.0-rc1
vanilla flushfull-v7
User 58.09 57.64
System 111.82 76.56
Elapsed 27.29 22.55
It's still a noticeable improvement with vmstat showing interrupts went
from roughly 500K per second to 45K per second.
The patch will have no impact on workloads with no memory pressure or have
relatively few mapped pages. It will have an unpredictable impact on the
workload running on the CPU being flushed as it'll depend on how many TLB
entries need to be refilled and how long that takes. Worst case, the TLB
will be completely cleared of active entries when the target PFNs were not
resident at all.
[sasha.levin@oracle.com: trace tlb flush after disabling preemption in try_to_unmap_flush]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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