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2016-06-25Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-1/+3
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 ...
2016-06-25init/main.c: fix initcall_blacklisted on ia64, ppc64 and parisc64Rasmus Villemoes1-1/+3
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: c8cdd2be213f (init/main.c: simplify initcall_blacklisted()) Link: http://lkml.kernel.org/r/1466027283-4065-1-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Yang Shi <yang.shi@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-25Clarify naming of thread info/stack allocatorsLinus Torvalds1-2/+2
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>
2016-05-28mm: use early_pfn_to_nid in page_ext_initYang Shi1-2/+1
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 b8f1a75d61d840 ("mm: call page_ext_init() after all struct pages are initialized") and fixes the same problem with a better approach. [1] http://lkml.kernel.org/r/CAAmzW4OUmyPwQjvd7QUfc6W1Aic__TyAuH80MLRZNMxKy0-wPQ@mail.gmail.com Link: http://lkml.kernel.org/r/1464198689-23458-1-git-send-email-yang.shi@linaro.org Signed-off-by: Yang Shi <yang.shi@linaro.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-21init/main.c: simplify initcall_blacklisted()Rasmus Villemoes1-5/+4
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>
2016-05-21printk/nmi: generic solution for safe printk in NMIPetr Mladek1-0/+1
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 a9edc8809328 ("x86/nmi: Perform a safe NMI stack trace on all CPUs"). The patchset brings two big advantages. First, it makes the NMI backtraces safe on all architectures for free. Second, it makes all NMI messages almost safe on all architectures (the temporary buffer is limited. We still should keep the number of messages in NMI context at minimum). Note that there already are several messages printed in NMI context: WARN_ON(in_nmi()), BUG_ON(in_nmi()), anything being printed out from MCE handlers. These are not easy to avoid. This patch reuses most of the code and makes it generic. It is useful for all messages and architectures that support NMI. The alternative printk_func is set when entering and is reseted when leaving NMI context. It queues IRQ work to copy the messages into the main ring buffer in a safe context. __printk_nmi_flush() copies all available messages and reset the buffer. Then we could use a simple cmpxchg operations to get synchronized with writers. There is also used a spinlock to get synchronized with other flushers. We do not longer use seq_buf because it depends on external lock. It would be hard to make all supported operations safe for a lockless use. It would be confusing and error prone to make only some operations safe. The code is put into separate printk/nmi.c as suggested by Steven Rostedt. It needs a per-CPU buffer and is compiled only on architectures that call nmi_enter(). This is achieved by the new HAVE_NMI Kconfig flag. The are MN10300 and Xtensa architectures. We need to clean up NMI handling there first. Let's do it separately. The patch is heavily based on the draft from Peter Zijlstra, see https://lkml.org/lkml/2015/6/10/327 [arnd@arndb.de: printk-nmi: use %zu format string for size_t] [akpm@linux-foundation.org: min_t->min - all types are size_t here] Signed-off-by: Petr Mladek <pmladek@suse.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Cc: Jan Kara <jack@suse.cz> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> [arm part] Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jiri Kosina <jkosina@suse.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: David Miller <davem@davemloft.net> Cc: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-21mm: call page_ext_init() after all struct pages are initializedYang Shi1-1/+2
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>
2016-03-16Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-3/+1
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 ...
2016-03-16init/main.c: use list_for_each_entry()Geliang Tang1-3/+1
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>
2016-03-15Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds1-15/+1
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 ...
2016-03-15Merge branch 'mm-readonly-for-linus' of ↵Linus Torvalds1-4/+23
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()
2016-03-01cpu/hotplug: Unpark smpboot threads from the state machineThomas Gleixner1-1/+0
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>
2016-03-01cpu/hotplug: Convert to a state machine for the control processorThomas Gleixner1-14/+1
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>
2016-02-22mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel ↵Kees Cook1-4/+23
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>
2016-02-09locking/lockdep: Eliminate lockdep_init()Andrey Ryabinin1-5/+0
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>
2016-01-21init/main.c: obsolete_checksetup can be booleanYaowei Bai1-5/+5
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>
2015-12-04rcu: Wire up rcu_end_inkernel_boot()Paul E. McKenney1-0/+2
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>
2015-09-10kmod: use system_unbound_wq instead of khelperFrederic Weisbecker1-1/+0
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>
2015-08-07fs, file table: reinit files_stat.max_files after deferred memory initialisationMel Gorman1-1/+1
Dave Hansen reported the following; My laptop has been behaving strangely with 4.2-rc2. Once I log in to my X session, I start getting all kinds of strange errors from applications and see this in my dmesg: VFS: file-max limit 8192 reached The problem is that the file-max is calculated before memory is fully initialised and miscalculates how much memory the kernel is using. This patch recalculates file-max after deferred memory initialisation. Note that using memory hotplug infrastructure would not have avoided this problem as the value is not recalculated after memory hot-add. 4.1: files_stat.max_files = 6582781 4.2-rc2: files_stat.max_files = 8192 4.2-rc2 patched: files_stat.max_files = 6562467 Small differences with the patch applied and 4.1 but not enough to matter. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Dave Hansen <dave.hansen@intel.com> Cc: Nicolai Stange <nicstange@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Alex Ng <alexng@microsoft.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-01mm: meminit: finish initialisation of struct pages before basic setupMel Gorman1-0/+2
Waiman Long reported that 24TB machines hit OOM during basic setup when struct page initialisation was deferred. One approach is to initialise memory on demand but it interferes with page allocator paths. This patch creates dedicated threads to initialise memory before basic setup. It then blocks on a rw_semaphore until completion as a wait_queue and counter is overkill. This may be slower to boot but it's simplier overall and also gets rid of a section mangling which existed so kswapd could do the initialisation. [akpm@linux-foundation.org: include rwsem.h, use DECLARE_RWSEM, fix comment, remove unneeded cast] Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Waiman Long <waiman.long@hp.com Cc: Nathan Zimmer <nzimmer@sgi.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Scott Norton <scott.norton@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-27Merge tag 'driver-core-4.2-rc1' of ↵Linus Torvalds1-10/+15
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the driver core / firmware changes for 4.2-rc1. A number of small changes all over the place in the driver core, and in the firmware subsystem. Nothing really major, full details in the shortlog. Some of it is a bit of churn, given that the platform driver probing changes was found to not work well, so they were reverted. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits) Revert "base/platform: Only insert MEM and IO resources" Revert "base/platform: Continue on insert_resource() error" Revert "of/platform: Use platform_device interface" Revert "base/platform: Remove code duplication" firmware: add missing kfree for work on async call fs: sysfs: don't pass count == 0 to bin file readers base:dd - Fix for typo in comment to function driver_deferred_probe_trigger(). base/platform: Remove code duplication of/platform: Use platform_device interface base/platform: Continue on insert_resource() error base/platform: Only insert MEM and IO resources firmware: use const for remaining firmware names firmware: fix possible use after free on name on asynchronous request firmware: check for file truncation on direct firmware loading firmware: fix __getname() missing failure check drivers: of/base: move of_init to driver_init drivers/base: cacheinfo: fix annoying typo when DT nodes are absent sysfs: disambiguate between "error code" and "failure" in comments driver-core: fix build for !CONFIG_MODULES driver-core: make __device_attach() static ...
2015-06-11ACPI / init: Switch over platform to the ACPI mode laterRafael J. Wysocki1-0/+1
Commit 73f7d1ca3263 "ACPI / init: Run acpi_early_init() before timekeeping_init()" moved the ACPI subsystem initialization, including the ACPI mode enabling, to an earlier point in the initialization sequence, to allow the timekeeping subsystem use ACPI early. Unfortunately, that resulted in boot regressions on some systems and the early ACPI initialization was moved toward its original position in the kernel initialization code by commit c4e1acbb35e4 "ACPI / init: Invoke early ACPI initialization later". However, that turns out to be insufficient, as boot is still broken on the Tyan S8812 mainboard. To fix that issue, split the ACPI early initialization code into two pieces so the majority of it still located in acpi_early_init() and the part switching over the platform into the ACPI mode goes into a new function, acpi_subsystem_init(), executed at the original early ACPI initialization spot. That fixes the Tyan S8812 boot problem, but still allows ACPI tables to be loaded earlier which is useful to the EFI code in efi_enter_virtual_mode(). Link: https://bugzilla.kernel.org/show_bug.cgi?id=97141 Fixes: 73f7d1ca3263 "ACPI / init: Run acpi_early_init() before timekeeping_init()" Reported-and-tested-by: Marius Tolzmann <tolzmann@molgen.mpg.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Lee, Chun-Yi <jlee@suse.com>
2015-05-20module: add extra argument for parse_params() callbackLuis R. Rodriguez1-10/+15
This adds an extra argument onto parse_params() to be used as a way to make the unused callback a bit more useful and generic by allowing the caller to pass on a data structure of its choice. An example use case is to allow us to easily make module parameters for every module which we will do next. @ parse @ identifier name, args, params, num, level_min, level_max; identifier unknown, param, val, doing; type s16; @@ extern char *parse_args(const char *name, char *args, const struct kernel_param *params, unsigned num, s16 level_min, s16 level_max, + void *arg, int (*unknown)(char *param, char *val, const char *doing + , void *arg )); @ parse_mod @ identifier name, args, params, num, level_min, level_max; identifier unknown, param, val, doing; type s16; @@ char *parse_args(const char *name, char *args, const struct kernel_param *params, unsigned num, s16 level_min, s16 level_max, + void *arg, int (*unknown)(char *param, char *val, const char *doing + , void *arg )) { ... } @ parse_args_found @ expression R, E1, E2, E3, E4, E5, E6; identifier func; @@ ( R = parse_args(E1, E2, E3, E4, E5, E6, + NULL, func); | R = parse_args(E1, E2, E3, E4, E5, E6, + NULL, &func); | R = parse_args(E1, E2, E3, E4, E5, E6, + NULL, NULL); | parse_args(E1, E2, E3, E4, E5, E6, + NULL, func); | parse_args(E1, E2, E3, E4, E5, E6, + NULL, &func); | parse_args(E1, E2, E3, E4, E5, E6, + NULL, NULL); ) @ parse_args_unused depends on parse_args_found @ identifier parse_args_found.func; @@ int func(char *param, char *val, const char *unused + , void *arg ) { ... } @ mod_unused depends on parse_args_found @ identifier parse_args_found.func; expression A1, A2, A3; @@ - func(A1, A2, A3); + func(A1, A2, A3, NULL); Generated-by: Coccinelle SmPL Cc: cocci@systeme.lip6.fr Cc: Tejun Heo <tj@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Hellwig <hch@infradead.org> Cc: Felipe Contreras <felipe.contreras@gmail.com> Cc: Ewan Milne <emilne@redhat.com> Cc: Jean Delvare <jdelvare@suse.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Jani Nikula <jani.nikula@intel.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-17kernel/fork.c: new function for max_threadsHeinrich Schuchardt1-2/+2
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the THREAD_SIZE. E.g. architecture hexagon may have page size 1M and thread size 4096. This would lead to a division by zero in the calculation of max_threads. With this patch the buggy code is moved to a separate function set_max_threads. The error is not fixed. After fixing the problem in a separate patch the new function can be reused to adjust max_threads after adding or removing memory. Argument mempages of function fork_init() is removed as totalram_pages is an exported symbol. The creation of separate patches for refactoring to a new function and for fixing the logic was suggested by Ingo Molnar. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+2
Merge first patchbomb from Andrew Morton: - arch/sh updates - ocfs2 updates - kernel/watchdog feature - about half of mm/ * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits) Documentation: update arch list in the 'memtest' entry Kconfig: memtest: update number of test patterns up to 17 arm: add support for memtest arm64: add support for memtest memtest: use phys_addr_t for physical addresses mm: move memtest under mm mm, hugetlb: abort __get_user_pages if current has been oom killed mm, mempool: do not allow atomic resizing memcg: print cgroup information when system panics due to panic_on_oom mm: numa: remove migrate_ratelimited mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE mm: split ET_DYN ASLR from mmap ASLR s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE mm: expose arch_mmap_rnd when available s390: standardize mmap_rnd() usage powerpc: standardize mmap_rnd() usage mips: extract logic for mmap_rnd() arm64: standardize mmap_rnd() usage x86: standardize mmap_rnd() usage arm: factor out mmap ASLR into mmap_rnd ...
2015-04-15lib/ioremap.c: add huge I/O map capability interfacesToshi Kani1-0/+2
Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when I/O mappings with pud/pmd are enabled on the kernel. ioremap_huge_init() calls arch_ioremap_pud_supported() and arch_ioremap_pmd_supported() to initialize the capabilities at boot-time. A new kernel option "nohugeiomap" is also added, so that user can disable the huge I/O map capabilities when necessary. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Robert Elliott <Elliott@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes from Ingo Molnar: "The main changes in this cycle were: - changes permitting use of call_rcu() and friends very early in boot, for example, before rcu_init() is invoked. - add in-kernel API to enable and disable expediting of normal RCU grace periods. - improve RCU's handling of (hotplug-) outgoing CPUs. - NO_HZ_FULL_SYSIDLE fixes. - tiny-RCU updates to make it more tiny. - documentation updates. - miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) cpu: Provide smpboot_thread_init() on !CONFIG_SMP kernels as well cpu: Defer smpboot kthread unparking until CPU known to scheduler rcu: Associate quiescent-state reports with grace period rcu: Yet another fix for preemption and CPU hotplug rcu: Add diagnostics to grace-period cleanup rcutorture: Default to grace-period-initialization delays rcu: Handle outgoing CPUs on exit from idle loop cpu: Make CPU-offline idle-loop transition point more precise rcu: Eliminate ->onoff_mutex from rcu_node structure rcu: Process offlining and onlining only at grace-period start rcu: Move rcu_report_unblock_qs_rnp() to common code rcu: Rework preemptible expedited bitmask handling rcu: Remove event tracing from rcu_cpu_notify(), used by offline CPUs rcutorture: Enable slow grace-period initializations rcu: Provide diagnostic option to slow down grace-period initialization rcu: Detect stalls caused by failure to propagate up rcu_node tree rcu: Eliminate empty HOTPLUG_CPU ifdef rcu: Simplify sync_rcu_preempt_exp_init() rcu: Put all orphan-callback-related code under same comment rcu: Consolidate offline-CPU callback initialization ...
2015-04-14Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree from Jiri Kosina: "Usual trivial tree updates. Nothing outstanding -- mostly printk() and comment fixes and unused identifier removals" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: goldfish: goldfish_tty_probe() is not using 'i' any more powerpc: Fix comment in smu.h qla2xxx: Fix printks in ql_log message lib: correct link to the original source for div64_u64 si2168, tda10071, m88ds3103: Fix firmware wording usb: storage: Fix printk in isd200_log_config() qla2xxx: Fix printk in qla25xx_setup_mode init/main: fix reset_device comment ipwireless: missing assignment goldfish: remove unreachable line of code coredump: Fix do_coredump() comment stacktrace.h: remove duplicate declaration task_struct smpboot.h: Remove unused function prototype treewide: Fix typo in printk messages treewide: Fix typo in printk messages mod_devicetable: fix comment for match_flags
2015-04-13cpu: Defer smpboot kthread unparking until CPU known to schedulerPaul E. McKenney1-0/+1
Currently, smpboot_unpark_threads() is invoked before the incoming CPU has been added to the scheduler's runqueue structures. This might potentially cause the unparked kthread to run on the wrong CPU, since the correct CPU isn't fully set up yet. That causes a sporadic, hard to debug boot crash triggering on some systems, reported by Borislav Petkov, and bisected down to: 2a442c9c6453 ("x86: Use common outgoing-CPU-notification code") This patch places smpboot_unpark_threads() in a CPU hotplug notifier with priority set so that these kthreads are unparked just after the CPU has been added to the runqueues. Reported-and-tested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-07init/main: fix reset_device commentFrans Klaver1-1/+1
Fix incorrect spelling of situation. Signed-off-by: Frans Klaver <fransklaver@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-03-05cpuset: initialize cpuset a bit earlyZefan Li1-1/+1
Now we call ss->bind() in cgroup_init(), so cgroup_init() will call cpuset_bind() and then the latter will access top_cpuset's cpumask, which is NULL, because cpuset_init() is called after cgroup_init() The simplest fix is to swap cgroup_init() and cpuset_init(). Cc: Vladimir Davydov <vdavydov@parallels.com> Fixes: 295458e67284 ("cgroup: call cgroup_subsys->bind on cgroup subsys initialization") Reported by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Vladimir Davydov <vdavydov@parallels.com>
2015-02-14init: remove CONFIG_INIT_FALLBACKAndy Lutomirski1-5/+0
CONFIG_INIT_FALLBACK adds config bloat without an obvious use case that makes it worth keeping around. Delete it. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Frank Rowand <frowand.list@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rob Landley <rob@landley.net> Cc: Shuah Khan <shuah.kh@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-22init: Get rid of x86ismsThomas Gleixner1-13/+0
The UP local API support can be set up from an early initcall. No need for horrible hackery in the init code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.827943883@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-17Merge branch 'for-linus' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile #2 from Al Viro: "Next pile (and there'll be one or two more). The large piece in this one is getting rid of /proc/*/ns/* weirdness; among other things, it allows to (finally) make nameidata completely opaque outside of fs/namei.c, making for easier further cleanups in there" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: coda_venus_readdir(): use file_inode() fs/namei.c: fold link_path_walk() call into path_init() path_init(): don't bother with LOOKUP_PARENT in argument fs/namei.c: new helper (path_cleanup()) path_init(): store the "base" pointer to file in nameidata itself make default ->i_fop have ->open() fail with ENXIO make nameidata completely opaque outside of fs/namei.c kill proc_ns completely take the targets of /proc/*/ns/* symlinks to separate fs bury struct proc_ns in fs/proc copy address of proc_ns_ops into ns_common new helpers: ns_alloc_inum/ns_free_inum make proc_ns_operations work with struct ns_common * instead of void * switch the rest of proc_ns_operations to working with &...->ns netns: switch ->get()/->put()/->install()/->inum() to working with &net->ns make mntns ->get()/->put()/->install()/->inum() work with &mnt_ns->ns common object embedded into various struct ....ns
2014-12-16Merge tag 'trace-3.19-2' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "As the merge window is still open, and this code was not as complex as I thought it might be. I'm pushing this in now. This will allow Thomas to debug his irq work for 3.20. This adds two new features: 1) Allow traceopoints to be enabled right after mm_init(). By passing in the trace_event= kernel command line parameter, tracepoints can be enabled at boot up. For debugging things like the initialization of interrupts, it is needed to have tracepoints enabled very early. People have asked about this before and this has been on my todo list. As it can be helpful for Thomas to debug his upcoming 3.20 IRQ work, I'm pushing this now. This way he can add tracepoints into the IRQ set up and have users enable them when things go wrong. 2) Have the tracepoints printed via printk() (the console) when they are triggered. If the irq code locks up or reboots the box, having the tracepoint output go into the kernel ring buffer is useless for debugging. But being able to add the tp_printk kernel command line option along with the trace_event= option will have these tracepoints printed as they occur, and that can be really useful for debugging early lock up or reboot problems. This code is not that intrusive and it passed all my tests. Thomas tried them out too and it works for his needs. Link: http://lkml.kernel.org/r/20141214201609.126831471@goodmis.org" * tag 'trace-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Add tp_printk cmdline to have tracepoints go to printk() tracing: Move enabling tracepoints to just after rcu_init()
2014-12-15tracing: Move enabling tracepoints to just after rcu_init()Steven Rostedt (Red Hat)1-0/+4
Enabling tracepoints at boot up can be very useful. The tracepoint can be initialized right after RCU has been. There's no need to wait for the early_initcall() to be called. That's too late for some things that can use tracepoints for debugging. Move the logic to enable tracepoints out of the initcalls and into init/main.c to right after rcu_init(). This also allows trace_printk() to be used early too. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412121539300.16494@nanos Link: http://lkml.kernel.org/r/20141214164104.307127356@goodmis.org Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-15Merge branch 'next' of ↵Linus Torvalds1-1/+5
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: "In terms of changes, there's general maintenance to the Smack, SELinux, and integrity code. The IMA code adds a new kconfig option, IMA_APPRAISE_SIGNED_INIT, which allows IMA appraisal to require signatures. Support for reading keys from rootfs before init is call is also added" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits) selinux: Remove security_ops extern security: smack: fix out-of-bounds access in smk_parse_smack() VFS: refactor vfs_read() ima: require signature based appraisal integrity: provide a hook to load keys when rootfs is ready ima: load x509 certificate from the kernel integrity: provide a function to load x509 certificate from the kernel integrity: define a new function integrity_read_file() Security: smack: replace kzalloc with kmem_cache for inode_smack Smack: Lock mode for the floor and hat labels ima: added support for new kernel cmdline parameter ima_template_fmt ima: allocate field pointers array on demand in template_desc_init_fields() ima: don't allocate a copy of template_fmt in template_desc_init_fields() ima: display template format in meas. list if template name length is zero ima: added error messages to template-related functions ima: use atomic bit operations to protect policy update interface ima: ignore empty and with whitespaces policy lines ima: no need to allocate entry for comment ima: report policy load status ima: use path names cache ...
2014-12-13mm/page_ext: resurrect struct page extending code for debuggingJoonsoo Kim1-0/+7
When we debug something, we'd like to insert some information to every page. For this purpose, we sometimes modify struct page itself. But, this has drawbacks. First, it requires re-compile. This makes us hesitate to use the powerful debug feature so development process is slowed down. And, second, sometimes it is impossible to rebuild the kernel due to third party module dependency. At third, system behaviour would be largely different after re-compile, because it changes size of struct page greatly and this structure is accessed by every part of kernel. Keeping this as it is would be better to reproduce errornous situation. This feature is intended to overcome above mentioned problems. This feature allocates memory for extended data per page in certain place rather than the struct page itself. This memory can be accessed by the accessor functions provided by this code. During the boot process, it checks whether allocation of huge chunk of memory is needed or not. If not, it avoids allocating memory at all. With this advantage, we can include this feature into the kernel in default and can avoid rebuild and solve related problems. Until now, memcg uses this technique. But, now, memcg decides to embed their variable to struct page itself and it's code to extend struct page has been removed. I'd like to use this code to develop debug feature, so this patch resurrect it. To help these things to work well, this patch introduces two callbacks for clients. One is the need callback which is mandatory if user wants to avoid useless memory allocation at boot-time. The other is optional, init callback, which is used to do proper initialization after memory is allocated. Detailed explanation about purpose of these functions is in code comment. Please refer it. Others are completely same with previous extension code in memcg. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> 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>
2014-12-11Merge branch 'nsfs' into for-nextAl Viro1-0/+2
2014-12-11take the targets of /proc/*/ns/* symlinks to separate fsAl Viro1-0/+2
New pseudo-filesystem: nsfs. Targets of /proc/*/ns/* live there now. It's not mountable (not even registered, so it's not in /proc/filesystems, etc.). Files on it *are* bindable - we explicitly permit that in do_loopback(). This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well. get_proc_ns() is a macro now (it's simply returning ->i_private; would have been an inline, if not for header ordering headache). proc_ns_inode() is an ex-parrot. The interface used in procfs is ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops). Dentries and inodes are never hashed; a non-counting reference to dentry is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path() if present. See ns_get_path()/ns_prune_dentry/nsfs_evict() for details of that mechanism. As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt; it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets from ns_get_path(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-11init: allow CONFIG_INIT_FALLBACK=n to disable defaults if init= failsAndy Lutomirski1-1/+6
If a user puts init=/whatever on the command line and /whatever can't be run, then the kernel will try a few default options before giving up. If init=/whatever came from a bootloader prompt, then this is unexpected but probably harmless. On the other hand, if it comes from a script (e.g. a tool like virtme or perhaps a future kselftest script), then the fallbacks are likely to exist, but they'll do the wrong thing. For example, they might unexpectedly invoke systemd. This adds a config option CONFIG_INIT_FALLBACK. If unset, then a failure to run the specified init= process be fatal. The tentative plan is to remove CONFIG_INIT_FALLBACK for 3.20. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Rob Landley <rob@landley.net> Cc: Chuck Ebbert <cebbert.lkml@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Shuah Khan <shuah.kh@samsung.com> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-11mm: embed the memcg pointer directly into struct pageJohannes Weiner1-7/+0
Memory cgroups used to have 5 per-page pointers. To allow users to disable that amount of overhead during runtime, those pointers were allocated in a separate array, with a translation layer between them and struct page. There is now only one page pointer remaining: the memcg pointer, that indicates which cgroup the page is associated with when charged. The complexity of runtime allocation and the runtime translation overhead is no longer justified to save that *potential* 0.19% of memory. With CONFIG_SLUB, page->mem_cgroup actually sits in the doubleword padding after the page->private member and doesn't even increase struct page, and then this patch actually saves space. Remaining users that care can still compile their kernels without CONFIG_MEMCG. text data bss dec hex filename 8828345 1725264 983040 11536649 b00909 vmlinux.old 8827425 1725264 966656 11519345 afc571 vmlinux.new [mhocko@suse.cz: update Documentation/cgroups/memory.txt] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vladimir Davydov <vdavydov@parallels.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Tejun Heo <tj@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-19Merge branch 'next' of ↵James Morris1-1/+5
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next
2014-11-18integrity: provide a hook to load keys when rootfs is readyDmitry Kasatkin1-1/+5
Keys can only be loaded once the rootfs is mounted. Initcalls are not suitable for that. This patch defines a special hook to load the x509 public keys onto the IMA keyring, before attempting to access any file. The keys are required for verifying the file's signature. The hook is called after the root filesystem is mounted and before the kernel calls 'init'. Changes in v3: * added more explanation to the patch description (Mimi) Changes in v2: * Hook renamed as 'integrity_load_keys()' to handle both IMA and EVM keys by integrity subsystem. * Hook patch moved after defining loading functions Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-11param: fix crash on bad kernel argumentsDaniel Thompson1-1/+1
Currently if the user passes an invalid value on the kernel command line then the kernel will crash during argument parsing. On most systems this is very hard to debug because the console hasn't been initialized yet. This is a regression due to commit 51e158c12aca ("param: hand arguments after -- straight to init") which, in response to the systemd debug controversy, made it possible to explicitly pass arguments to init. To achieve this parse_args() was extended from simply returning an error code to returning a pointer. Regretably the new init args logic does not perform a proper validity check on the pointer resulting in a crash. This patch fixes the validity check. Should the check fail then no arguments will be passed to init. This is reasonable and matches how the kernel treats its own arguments (i.e. no error recovery). Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: stable@vger.kernel.org Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-14kernel/param: consolidate __{start,stop}___param[] in <linux/moduleparam.h>Geert Uytterhoeven1-2/+0
Consolidate the various external const and non-const declarations of __start___param[] and __stop___param in <linux/moduleparam.h>. This requires making a few struct kernel_param pointers in kernel/params.c const. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-13Merge branch 'sched-core-for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave Hansen) - Various sched/idle refinements for better idle handling (Nicolas Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot) - sched/numa updates and optimizations (Rik van Riel) - sysbench speedup (Vincent Guittot) - capacity calculation cleanups/refactoring (Vincent Guittot) - Various cleanups to thread group iteration (Oleg Nesterov) - Double-rq-lock removal optimization and various refactorings (Kirill Tkhai) - various sched/deadline fixes ... and lots of other changes" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) sched/dl: Use dl_bw_of() under rcu_read_lock_sched() sched/fair: Delete resched_cpu() from idle_balance() sched, time: Fix build error with 64 bit cputime_t on 32 bit systems sched: Improve sysbench performance by fixing spurious active migration sched/x86: Fix up typo in topology detection x86, sched: Add new topology for multi-NUMA-node CPUs sched/rt: Use resched_curr() in task_tick_rt() sched: Use rq->rd in sched_setaffinity() under RCU read lock sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask' sched: Use dl_bw_of() under RCU read lock sched/fair: Remove duplicate code from can_migrate_task() sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW sched: print_rq(): Don't use tasklist_lock sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock() sched: Fix the task-group check in tg_has_rt_tasks() sched/fair: Leverage the idle state info when choosing the "idlest" cpu sched: Let the scheduler see CPU idle states sched/deadline: Fix inter- exclusive cpusets migrations sched/deadline: Clear dl_entity params when setscheduling to different class sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault() ...
2014-10-13Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes in this cycle were: - changes related to No-CBs CPUs and NO_HZ_FULL - RCU-tasks implementation - torture-test updates - miscellaneous fixes - locktorture updates - RCU documentation updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (81 commits) workqueue: Use cond_resched_rcu_qs macro workqueue: Add quiescent state between work items locktorture: Cleanup header usage locktorture: Cannot hold read and write lock locktorture: Fix __acquire annotation for spinlock irq locktorture: Support rwlocks rcu: Eliminate deadlock between CPU hotplug and expedited grace periods locktorture: Document boot/module parameters rcutorture: Rename rcutorture_runnable parameter locktorture: Add test scenario for rwsem_lock locktorture: Add test scenario for mutex_lock locktorture: Make torture scripting account for new _runnable name locktorture: Introduce torture context locktorture: Support rwsems locktorture: Add infrastructure for torturing read locks torture: Address race in module cleanup locktorture: Make statistics generic locktorture: Teach about lock debugging locktorture: Support mutexes locktorture: Add documentation ...
2014-09-19init/main.c: Give init_task a canaryAaron Tomlin1-0/+1
Tasks get their end of stack set to STACK_END_MAGIC with the aim to catch stack overruns. Currently this feature does not apply to init_task. This patch removes this restriction. Note that a similar patch was posted by Prarit Bhargava some time ago but was never merged: http://marc.info/?l=linux-kernel&m=127144305403241&w=2 Signed-off-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: aneesh.kumar@linux.vnet.ibm.com Cc: dzickus@redhat.com Cc: bmr@redhat.com Cc: jcastillo@redhat.com Cc: jgh@redhat.com Cc: minchan@kernel.org Cc: tglx@linutronix.de Cc: hannes@cmpxchg.org Cc: Alex Thorlton <athorlton@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Daeseok Youn <daeseok.youn@gmail.com> Cc: David Rientjes <rientjes@google.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Michael Opdenacker <michael.opdenacker@free-electrons.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1410527779-8133-2-git-send-email-atomlin@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16rcu: Fix attempt to avoid unsolicited offloading of callbacksPaul E. McKenney1-0/+1
Commit b58cc46c5f6b (rcu: Don't offload callbacks unless specifically requested) failed to adjust the callback lists of the CPUs that are known to be no-CBs CPUs only because they are also nohz_full= CPUs. This failure can result in callbacks that are posted during early boot getting stranded on nxtlist for CPUs whose no-CBs property becomes apparent late, and there can also be spurious warnings about offline CPUs posting callbacks. This commit fixes these problems by adding an early-boot rcu_init_nohz() that properly initializes the no-CBs CPUs. Note that kernels built with CONFIG_RCU_NOCB_CPU_ALL=y or with CONFIG_RCU_NOCB_CPU=n do not exhibit this bug. Neither do kernels booted without the nohz_full= boot parameter. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com> Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>