Commit graph

21875 commits

Author SHA1 Message Date
David Collins
d4b065ff47 sysctl: add boot_reason and cold_boot sysctl entries for arm64
Define boot_reason and cold_boot variables in the arm64 version
of setup.c so that arm64 targets can export the boot_reason and
cold_boot sysctl entries.

This feature is required by the qpnp-power-on driver.

Change-Id: Id2d4ff5b8caa2e6a35d4ac61e338963d602c8b84
Signed-off-by: David Collins <collinsd@codeaurora.org>
[osvaldob: resolved trival merge conflicts]
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>
2016-03-01 12:22:13 -08:00
Luis R. Rodriguez
e2f712dc92 modules: fix modparam async_probe request
commit 4355efbd80482a961cae849281a8ef866e53d55c upstream.

Commit f2411da746 ("driver-core: add driver module
asynchronous probe support") added async probe support,
in two forms:

  * in-kernel driver specification annotation
  * generic async_probe module parameter (modprobe foo async_probe)

To support the generic kernel parameter parse_args() was
extended via commit ecc8617053 ("module: add extra
argument for parse_params() callback") however commit
failed to f2411da746 failed to add the required argument.

This causes a crash then whenever async_probe generic
module parameter is used. This was overlooked when the
form in which in-kernel async probe support was reworked
a bit... Fix this as originally intended.

Cc: Hannes Reinecke <hare@suse.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> [minimized]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:25 -08:00
Rusty Russell
a24d9a2fee module: wrapper for symbol name.
commit 2e7bac536106236104e9e339531ff0fcdb7b8147 upstream.

This trivial wrapper adds clarity and makes the following patch
smaller.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:25 -08:00
Thomas Gleixner
82e730baa9 itimers: Handle relative timers with CONFIG_TIME_LOW_RES proper
commit 51cbb5242a41700a3f250ecfb48dcfb7e4375ea4 upstream.

As Helge reported for timerfd we have the same issue in itimers. We return
remaining time larger than the programmed relative time to user space in case
of CONFIG_TIME_LOW_RES=y. Use the proper function to adjust the extra time
added in hrtimer_start_range_ns().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Helge Deller <deller@gmx.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: dhowells@redhat.com
Link: http://lkml.kernel.org/r/20160114164159.528222587@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:25 -08:00
Thomas Gleixner
1c94da3e74 posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper
commit 572c39172684c3711e4a03c9a7380067e2b0661c upstream.

As Helge reported for timerfd we have the same issue in posix timers. We
return remaining time larger than the programmed relative time to user space
in case of CONFIG_TIME_LOW_RES=y. Use the proper function to adjust the extra
time added in hrtimer_start_range_ns().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Helge Deller <deller@gmx.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: dhowells@redhat.com
Link: http://lkml.kernel.org/r/20160114164159.450510905@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:25 -08:00
Mateusz Guzik
e5e99792b6 prctl: take mmap sem for writing to protect against others
commit ddf1d398e517e660207e2c807f76a90df543a217 upstream.

An unprivileged user can trigger an oops on a kernel with
CONFIG_CHECKPOINT_RESTORE.

proc_pid_cmdline_read takes mmap_sem for reading and obtains args + env
start/end values. These get sanity checked as follows:
        BUG_ON(arg_start > arg_end);
        BUG_ON(env_start > env_end);

These can be changed by prctl_set_mm. Turns out also takes the semaphore for
reading, effectively rendering it useless. This results in:

  kernel BUG at fs/proc/base.c:240!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: virtio_net
  CPU: 0 PID: 925 Comm: a.out Not tainted 4.4.0-rc8-next-20160105dupa+ #71
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  task: ffff880077a68000 ti: ffff8800784d0000 task.ti: ffff8800784d0000
  RIP: proc_pid_cmdline_read+0x520/0x530
  RSP: 0018:ffff8800784d3db8  EFLAGS: 00010206
  RAX: ffff880077c5b6b0 RBX: ffff8800784d3f18 RCX: 0000000000000000
  RDX: 0000000000000002 RSI: 00007f78e8857000 RDI: 0000000000000246
  RBP: ffff8800784d3e40 R08: 0000000000000008 R09: 0000000000000001
  R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000050
  R13: 00007f78e8857800 R14: ffff88006fcef000 R15: ffff880077c5b600
  FS:  00007f78e884a740(0000) GS:ffff88007b200000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 00007f78e8361770 CR3: 00000000790a5000 CR4: 00000000000006f0
  Call Trace:
    __vfs_read+0x37/0x100
    vfs_read+0x82/0x130
    SyS_read+0x58/0xd0
    entry_SYSCALL_64_fastpath+0x12/0x76
  Code: 4c 8b 7d a8 eb e9 48 8b 9d 78 ff ff ff 4c 8b 7d 90 48 8b 03 48 39 45 a8 0f 87 f0 fe ff ff e9 d1 fe ff ff 4c 8b 7d 90 eb c6 0f 0b <0f> 0b 0f 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00
  RIP   proc_pid_cmdline_read+0x520/0x530
  ---[ end trace 97882617ae9c6818 ]---

Turns out there are instances where the code just reads aformentioned
values without locking whatsoever - namely environ_read and get_cmdline.

Interestingly these functions look quite resilient against bogus values,
but I don't believe this should be relied upon.

The first patch gets rid of the oops bug by grabbing mmap_sem for
writing.

The second patch is optional and puts locking around aformentioned
consumers for safety.  Consumers of other fields don't seem to benefit
from similar treatment and are left untouched.

This patch (of 2):

The code was taking the semaphore for reading, which does not protect
against readers nor concurrent modifications.

The problem could cause a sanity checks to fail in procfs's cmdline
reader, resulting in an OOPS.

Note that some functions perform an unlocked read of various mm fields,
but they seem to be fine despite possible modificaton.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anshuman Khandual <anshuman.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:25 -08:00
Thomas Gleixner
acaf84251f futex: Drop refcount if requeue_pi() acquired the rtmutex
commit fb75a4282d0d9a3c7c44d940582c2d226cf3acfb upstream.

If the proxy lock in the requeue loop acquires the rtmutex for a
waiter then it acquired also refcount on the pi_state related to the
futex, but the waiter side does not drop the reference count.

Add the missing free_pi_state() call.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <darren@dvhart.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Bhuvanesh_Surachari@mentor.com
Cc: Andy Lowe <Andy_Lowe@mentor.com>
Link: http://lkml.kernel.org/r/20151219200607.178132067@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:23 -08:00
Toshi Kani
30066dcdf9 devm_memremap_release(): fix memremap'd addr handling
commit 9273a8bbf58a15051e53a777389a502420ddc60e upstream.

The pmem driver calls devm_memremap() to map a persistent memory range.
When the pmem driver is unloaded, this memremap'd range is not released
so the kernel will leak a vma.

Fix devm_memremap_release() to handle a given memremap'd address
properly.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:23 -08:00
Jann Horn
969624b7c1 ptrace: use fsuid, fsgid, effective creds for fs access checks
commit caaee6234d05a58c5b4d05e7bf766131b810a657 upstream.

By checking the effective credentials instead of the real UID / permitted
capabilities, ensure that the calling process actually intended to use its
credentials.

To ensure that all ptrace checks use the correct caller credentials (e.g.
in case out-of-tree code or newly added code omits the PTRACE_MODE_*CREDS
flag), use two new flags and require one of them to be set.

The problem was that when a privileged task had temporarily dropped its
privileges, e.g.  by calling setreuid(0, user_uid), with the intent to
perform following syscalls with the credentials of a user, it still passed
ptrace access checks that the user would not be able to pass.

While an attacker should not be able to convince the privileged task to
perform a ptrace() syscall, this is a problem because the ptrace access
check is reused for things in procfs.

In particular, the following somewhat interesting procfs entries only rely
on ptrace access checks:

 /proc/$pid/stat - uses the check for determining whether pointers
     should be visible, useful for bypassing ASLR
 /proc/$pid/maps - also useful for bypassing ASLR
 /proc/$pid/cwd - useful for gaining access to restricted
     directories that contain files with lax permissions, e.g. in
     this scenario:
     lrwxrwxrwx root root /proc/13020/cwd -> /root/foobar
     drwx------ root root /root
     drwxr-xr-x root root /root/foobar
     -rw-r--r-- root root /root/foobar/secret

Therefore, on a system where a root-owned mode 6755 binary changes its
effective credentials as described and then dumps a user-specified file,
this could be used by an attacker to reveal the memory layout of root's
processes or reveal the contents of files he is not allowed to access
(through /proc/$pid/cwd).

[akpm@linux-foundation.org: fix warning]
Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25 12:01:16 -08:00
Raghavendra K T
a800cbddbc sched: Fix crash in sched_init_numa()
commit 9c03ee147193645be4c186d3688232fa438c57c7 upstream.

The following PowerPC commit:

  c118baf802 ("arch/powerpc/mm/numa.c: do not allocate bootmem memory for non existing nodes")

avoids allocating bootmem memory for non existent nodes.

But when DEBUG_PER_CPU_MAPS=y is enabled, my powerNV system failed to boot
because in sched_init_numa(), cpumask_or() operation was done on
unallocated nodes.

Fix that by making cpumask_or() operation only on existing nodes.

[ Tested with and w/o DEBUG_PER_CPU_MAPS=y on x86 and PowerPC. ]

Reported-by: Jan Stancek <jstancek@redhat.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: <gkurz@linux.vnet.ibm.com>
Cc: <grant.likely@linaro.org>
Cc: <nikunj@linux.vnet.ibm.com>
Cc: <vdavydov@parallels.com>
Cc: <linuxppc-dev@lists.ozlabs.org>
Cc: <linux-mm@kvack.org>
Cc: <peterz@infradead.org>
Cc: <benh@kernel.crashing.org>
Cc: <paulus@samba.org>
Cc: <mpe@ellerman.id.au>
Cc: <anton@samba.org>
Link: http://lkml.kernel.org/r/1452884483-11676-1-git-send-email-raghavendra.kt@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-17 12:31:02 -08:00
Thomas Gleixner
dd0d511548 hrtimer: Handle remaining time proper for TIME_LOW_RES
commit 203cbf77de59fc8f13502dcfd11350c6d4a5c95f upstream.

If CONFIG_TIME_LOW_RES is enabled we add a jiffie to the relative timeout to
prevent short sleeps, but we do not account for that in interfaces which
retrieve the remaining time.

Helge observed that timerfd can return a remaining time larger than the
relative timeout. That's not expected and breaks userland test programs.

Store the information that the timer was armed relative and provide functions
to adjust the remaining time. To avoid bloating the hrtimer struct make state
a u8, which as a bonus results in better code on x86 at least.

Reported-and-tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: dhowells@redhat.com
Link: http://lkml.kernel.org/r/20160114164159.273328486@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-17 12:30:57 -08:00
Tejun Heo
a623f87a72 printk: do cond_resched() between lines while outputting to consoles
commit 8d91f8b15361dfb438ab6eb3b319e2ded43458ff upstream.

@console_may_schedule tracks whether console_sem was acquired through
lock or trylock.  If the former, we're inside a sleepable context and
console_conditional_schedule() performs cond_resched().  This allows
console drivers which use console_lock for synchronization to yield
while performing time-consuming operations such as scrolling.

However, the actual console outputting is performed while holding
irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
before starting outputting lines.  Also, only a few drivers call
console_conditional_schedule() to begin with.  This means that when a
lot of lines need to be output by console_unlock(), for example on a
console registration, the task doing console_unlock() may not yield for
a long time on a non-preemptible kernel.

If this happens with a slow console devices, for example a serial
console, the outputting task may occupy the cpu for a very long time.
Long enough to trigger softlockup and/or RCU stall warnings, which in
turn pile more messages, sometimes enough to trigger the next cycle of
warnings incapacitating the system.

Fix it by making console_unlock() insert cond_resched() between lines if
@console_may_schedule.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Calvin Owens <calvinowens@fb.com>
Acked-by: Jan Kara <jack@suse.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-17 12:30:57 -08:00
Steven Rostedt
bf46aa7ec7 tracing/stacktrace: Show entire trace if passed in function not found
commit 6ccd83714a009ee301b50c15f6c3a5dc1f30164c upstream.

When a max stack trace is discovered, the stack dump is saved. In order to
not record the overhead of the stack tracer, the ip of the traced function
is looked for within the dump. The trace is started from the location of
that function. But if for some reason the ip is not found, the entire stack
trace is then truncated. That's not very useful. Instead, print everything
if the ip of the traced function is not found within the trace.

This issue showed up on s390.

Link: http://lkml.kernel.org/r/20160129102241.1b3c9c04@gandalf.local.home

Fixes: 72ac426a5b ("tracing: Clean up stack tracing and fix fentry updates")
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-17 12:30:57 -08:00
Steven Rostedt (Red Hat)
cc6d98006b tracing: Fix stacktrace skip depth in trace_buffer_unlock_commit_regs()
commit 7717c6be699975f6733d278b13b7c4295d73caf6 upstream.

While cleaning the stacktrace code I unintentially changed the skip depth of
trace_buffer_unlock_commit_regs() from 0 to 6. kprobes uses this function,
and with skipping 6 call backs, it can easily produce no stack.

Here's how I tested it:

 # echo 'p:ext4_sync_fs ext4_sync_fs ' > /sys/kernel/debug/tracing/kprobe_events
 # echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable
 # cat /sys/kernel/debug/trace
            sync-2394  [005]   502.457060: ext4_sync_fs: (ffffffff81317650)
            sync-2394  [005]   502.457063: kernel_stack:         <stack trace>
            sync-2394  [005]   502.457086: ext4_sync_fs: (ffffffff81317650)
            sync-2394  [005]   502.457087: kernel_stack:         <stack trace>
            sync-2394  [005]   502.457091: ext4_sync_fs: (ffffffff81317650)

After putting back the skip stack to zero, we have:

            sync-2270  [000]   748.052693: ext4_sync_fs: (ffffffff81317650)
            sync-2270  [000]   748.052695: kernel_stack:         <stack trace>
 => iterate_supers (ffffffff8126412e)
 => sys_sync (ffffffff8129c4b6)
 => entry_SYSCALL_64_fastpath (ffffffff8181f0b2)
            sync-2270  [000]   748.053017: ext4_sync_fs: (ffffffff81317650)
            sync-2270  [000]   748.053019: kernel_stack:         <stack trace>
 => iterate_supers (ffffffff8126412e)
 => sys_sync (ffffffff8129c4b6)
 => entry_SYSCALL_64_fastpath (ffffffff8181f0b2)
            sync-2270  [000]   748.053381: ext4_sync_fs: (ffffffff81317650)
            sync-2270  [000]   748.053383: kernel_stack:         <stack trace>
 => iterate_supers (ffffffff8126412e)
 => sys_sync (ffffffff8129c4b6)
 => entry_SYSCALL_64_fastpath (ffffffff8181f0b2)

Fixes: 73dddbb57b "tracing: Only create stacktrace option when STACKTRACE is configured"
Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-17 12:30:56 -08:00
Colin Cross
55d35d82b7 hardlockup: detect hard lockups without NMIs using secondary cpus
Emulate NMIs on systems where they are not available by using timer
interrupts on other cpus.  Each cpu will use its softlockup hrtimer
to check that the next cpu is processing hrtimer interrupts by
verifying that a counter is increasing.

This patch is useful on systems where the hardlockup detector is not
available due to a lack of NMIs, for example most ARM SoCs.
Without this patch any cpu stuck with interrupts disabled can
cause a hardware watchdog reset with no debugging information,
but with this patch the kernel can detect the lockup and panic,
which can result in useful debugging info.

Change-Id: Ia5faf50243e19c1755201212e04c8892d929785a
Signed-off-by: Colin Cross <ccross@android.com>
2016-02-16 13:54:19 -08:00
dcashman
d49d88766b FROMLIST: mm: mmap: Add new /proc tunable for mmap_base ASLR.
(cherry picked from commit https://lkml.org/lkml/2015/12/21/337)

ASLR  only uses as few as 8 bits to generate the random offset for the
mmap base address on 32 bit architectures. This value was chosen to
prevent a poorly chosen value from dividing the address space in such
a way as to prevent large allocations. This may not be an issue on all
platforms. Allow the specification of a minimum number of bits so that
platforms desiring greater ASLR protection may determine where to place
the trade-off.

Bug: 24047224
Signed-off-by: Daniel Cashman <dcashman@android.com>
Signed-off-by: Daniel Cashman <dcashman@google.com>
Change-Id: Ibf9ed3d4390e9686f5cc34f605d509a20d40e6c2
2016-02-16 13:54:14 -08:00
Amit Pundir
29a4f01daa mm: private anonymous memory build fixes for 4.4
Update vma_merge() call in private anonymous memory prctl,
introduced in AOSP commit ee8c5f78f09a
"mm: add a field to store names for private anonymous memory",
so as to align with changes from upstream commit 19a809afe2
"userfaultfd: teach vma_merge to merge across vma->vm_userfaultfd_ctx".

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2016-02-16 13:54:13 -08:00
Colin Cross
586278d78b mm: add a field to store names for private anonymous memory
Userspace processes often have multiple allocators that each do
anonymous mmaps to get memory.  When examining memory usage of
individual processes or systems as a whole, it is useful to be
able to break down the various heaps that were allocated by
each layer and examine their size, RSS, and physical memory
usage.

This patch adds a user pointer to the shared union in
vm_area_struct that points to a null terminated string inside
the user process containing a name for the vma.  vmas that
point to the same address will be merged, but vmas that
point to equivalent strings at different addresses will
not be merged.

Userspace can set the name for a region of memory by calling
prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name);
Setting the name to NULL clears it.

The names of named anonymous vmas are shown in /proc/pid/maps
as [anon:<name>] and in /proc/pid/smaps in a new "Name" field
that is only present for named vmas.  If the userspace pointer
is no longer valid all or part of the name will be replaced
with "<fault>".

The idea to store a userspace pointer to reduce the complexity
within mm (at the expense of the complexity of reading
/proc/pid/mem) came from Dave Hansen.  This results in no
runtime overhead in the mm subsystem other than comparing
the anon_name pointers when considering vma merging.  The pointer
is stored in a union with fieds that are only used on file-backed
mappings, so it does not increase memory usage.

Includes fix from Jed Davis <jld@mozilla.com> for typo in
prctl_set_vma_anon_name, which could attempt to set the name
across two vmas at the same time due to a typo, which might
corrupt the vma list.  Fix it to use tmp instead of end to limit
the name setting to a single vma at a time.

Change-Id: I9aa7b6b5ef536cd780599ba4e2fba8ceebe8b59f
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
2016-02-16 13:54:13 -08:00
Rik van Riel
f8ade3666c add extra free kbytes tunable
Add a userspace visible knob to tell the VM to keep an extra amount
of memory free, by increasing the gap between each zone's min and
low watermarks.

This is useful for realtime applications that call system
calls and have a bound on the number of allocations that happen
in any short time period.  In this application, extra_free_kbytes
would be left at an amount equal to or larger than than the
maximum number of allocations that happen in any burst.

It may also be useful to reduce the memory use of virtual
machines (temporarily?), in a way that does not cause memory
fragmentation like ballooning does.

[ccross]
Revived for use on old kernels where no other solution exists.
The tunable will be removed on kernels that do better at avoiding
direct reclaim.

Change-Id: I765a42be8e964bfd3e2886d1ca85a29d60c3bb3e
Signed-off-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Colin Cross <ccross@android.com>
2016-02-16 13:54:12 -08:00
Arve Hjønnevåg
2774238025 ARM: Fix "Make low-level printk work" to use a separate config option
Change-Id: I5ca8db61b595adc642a07ea187bd41fd7636840e
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2016-02-16 13:54:03 -08:00
Nishanth Menon
4e09c51018 panic: Add board ID to panic output
At times, it is necessary for boards to provide some additional information
as part of panic logs. Provide information on the board hardware as part
of panic logs.

It is safer to print this information at the very end in case something
bad happens as part of the information retrieval itself.

To use this, set global mach_panic_string to an appropriate string in the
board file.

Change-Id: Id12cdda87b0cd2940dd01d52db97e6162f671b4d
Signed-off-by: Nishanth Menon <nm@ti.com>
2016-02-16 13:54:02 -08:00
Tony Lindgren
3200304ca3 ARM: Make low-level printk work
Makes low-level printk work.

Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-02-16 13:54:01 -08:00
San Mehat
9d19f72b43 proc: smaps: Allow smaps access for CAP_SYS_RESOURCE
Signed-off-by: San Mehat <san@google.com>
2016-02-16 13:53:50 -08:00
Micha Kalfon
d4d049c55d prctl: make PR_SET_TIMERSLACK_PID pid namespace aware
Make PR_SET_TIMERSLACK_PID consider pid namespace and resolve the
target pid in the caller's namespace. Otherwise, calls from pid
namespace other than init would fail or affect the wrong task.

Change-Id: I1da15196abc4096536713ce03714e99d2e63820a
Signed-off-by: Micha Kalfon <micha@cellrox.com>
Acked-by: Oren Laadan <orenl@cellrox.com>
2016-02-16 13:53:49 -08:00
Micha Kalfon
18f42f60be prctl: fix misplaced PR_SET_TIMERSLACK_PID case
The case clause for the PR_SET_TIMERSLACK_PID option was placed inside
the an internal switch statement for PR_MCE_KILL (see commits 37a591d4
and 8ae872f1) . This commit moves it to the right place.

Change-Id: I63251669d7e2f2aa843d1b0900e7df61518c3dea
Signed-off-by: Micha Kalfon <micha@cellrox.com>
Acked-by: Oren Laadan <orenl@cellrox.com>
2016-02-16 13:53:48 -08:00
Ruchi Kandoi
2476d3c241 prctl: adds the capable(CAP_SYS_NICE) check to PR_SET_TIMERSLACK_PID.
Adds a capable() check to make sure that arbitary apps do not change the
timer slack for other apps.

Bug: 15000427
Change-Id: I558a2551a0e3579c7f7e7aae54b28aa9d982b209
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2016-02-16 13:53:48 -08:00
Ruchi Kandoi
f2902f9065 prctl: adds PR_SET_TIMERSLACK_PID for setting timer slack of an arbitrary thread.
Second argument is similar to PR_SET_TIMERSLACK, if non-zero then the
slack is set to that value otherwise sets it to the default for the thread.

Takes PID of the thread as the third argument.

This allows power/performance management software to set timer slack for
other threads according to its policy for the thread (such as when the
thread is designated foreground vs. background activity)

Change-Id: I744d451ff4e60dae69f38f53948ff36c51c14a3f
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2016-02-16 13:53:47 -08:00
Amit Pundir
703920c14a cgroup: refactor allow_attach handler for 4.4
Refactor *allow_attach() handler to align it with the changes
from mainline commit 1f7dd3e5a6 "cgroup: fix handling of
multi-destination migration from subtree_control enabling".

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2016-02-16 13:53:46 -08:00
Dmitry Shmidt
69db8fca42 cgroup: fix cgroup_taskset_for_each call in allow_attach() for 4.1
Change-Id: I05013f6e76c30b0ece3671f9f2b4bbdc626cd35c
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
2016-02-16 13:53:46 -08:00
Christian Poetzsch
f4adb71017 Fix generic cgroup subsystem permission checks
In 53b5e2f generic cgroup subsystem permission checks have been added.
When this is been done within procs_write an empty taskset is added to
the tasks css set. When a task later on migrates to a new group we see a
dmesg warning cause the mg_node isn't empty (cgroup.c:2086). Cause this
happens all the time this spams dmesg.

I am not really familiar with this code, but it looks to me like adding
the taskset is just a temporary action in this context. Therefore this
taskset should be removed after the actual check. This is what this fix
does.

This problem was seen and the fix tested on x86 using l-mr1 and master.

Change-Id: I9894d39e8b5692ef65149002b07e65a84a33ffea
Signed-off-by: Christian Poetzsch <christian.potzsch@imgtec.com>
2016-02-16 13:53:45 -08:00
Rom Lemarchand
0d6687a82a cgroup: Fix issues in allow_attach callback
- Return -EINVAL when cgroups support isn't enabled
- Add allow_attach callback in CPU cgroups

Change-Id: Id3360b4a39919524fc4b6fcbd44fa2050009f000
Signed-off-by: Rom Lemarchand <romlem@android.com>
2016-02-16 13:53:44 -08:00
Colin Cross
1811046286 cgroup: Add generic cgroup subsystem permission checks
Rather than using explicit euid == 0 checks when trying to move
tasks into a cgroup via CFS, move permission checks into each
specific cgroup subsystem. If a subsystem does not specify a
'allow_attach' handler, then we fall back to doing our checks
the old way.

Use the 'allow_attach' handler for the 'cpu' cgroup to allow
non-root processes to add arbitrary processes to a 'cpu' cgroup
if it has the CAP_SYS_NICE capability set.

This version of the patch adds a 'allow_attach' handler instead
of reusing the 'can_attach' handler.  If the 'can_attach' handler
is reused, a new cgroup that implements 'can_attach' but not
the permission checks could end up with no permission checks
at all.

Change-Id: Icfa950aa9321d1ceba362061d32dc7dfa2c64f0c
Original-Author: San Mehat <san@google.com>
Signed-off-by: Colin Cross <ccross@android.com>
2016-02-16 13:53:43 -08:00
Rom Lemarchand
6809864a2c cgroup: refactor allow_attach function into common code
move cpu_cgroup_allow_attach to a common subsys_cgroup_allow_attach.
This allows any process with CAP_SYS_NICE to move tasks across cgroups if
they use this function as their allow_attach handler.

Bug: 18260435
Change-Id: I6bb4933d07e889d0dc39e33b4e71320c34a2c90f
Signed-off-by: Rom Lemarchand <romlem@android.com>
2016-02-16 13:53:42 -08:00
Ruchi Kandoi
1f027b30b5 wakeup_reason: use vsnprintf instead of snsprintf for vargs.
Bug: 22368519
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2016-02-16 13:53:42 -08:00
Amit Pundir
45e6e57272 power: wakeup_reason: fix suspend time reporting
Suspend time reporting Change-Id: I2cb9a9408a5fd12166aaec11b935a0fd6a408c63
(Power: Report suspend times from last_suspend_time), is broken on 3.16+
kernels because get_xtime_and_monotonic_and_sleep_offset() hrtimer helper
routine is removed from kernel timekeeping.

The replacement helper routines ktime_get_update_offsets_{tick,now}()
are private to core kernel timekeeping so we can't use them, hence using
ktime_get() and ktime_get_boottime() instead and sampling the time twice.

Idea is to use Monotonic boottime offset to calculate total time spent
in last suspend state and CLOCK_MONOTONIC to calculate time spent in
last suspend-resume process.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
2016-02-16 13:53:41 -08:00
jinqian
1cc3aac268 Power: Report suspend times from last_suspend_time
This node epxorts two values separated by space.
From left to right:
1. time spent in suspend/resume process
2. time spent sleep in suspend state

Change-Id: I2cb9a9408a5fd12166aaec11b935a0fd6a408c63
2016-02-16 13:53:40 -08:00
Dylan Reid
e710ba39fa power: Remove HAS_WAKELOCK config and document WAKELOCK
Remove the HAS_WAKELOCK config as it doesn't seem to have been used in
the 3.10 or 3.14 kernels.

Add some Documentation to CONFIG_WAKELOCK so that it is selectable and
can be disabled is desired.

Signed-off-by: Dylan Reid <dgreid@chromium.org>
2016-02-16 13:53:40 -08:00
Lorenzo Colitti
49f054b7c5 Make suspend abort reason logging depend on CONFIG_PM_SLEEP
This unbreaks the build on architectures such as um that do not
support CONFIG_PM_SLEEP.

Change-Id: Ia846ed0a7fca1d762ececad20748d23610e8544f
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
2016-02-16 13:53:39 -08:00
Dmitry Shmidt
dd0c7788b6 power: Add check_wakeup_reason() to verify wakeup source irq
Wakeup reason is set before driver resume handlers are called.
It is cleared before driver suspend handlers are called, on
PM_SUSPEND_PREPARE.

Change-Id: I04218c9b0c115a7877e8029c73e6679ff82e0aa4
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
2016-02-16 13:53:39 -08:00
Ruchi Kandoi
57caa2ad5c power: Adds functionality to log the last suspend abort reason.
Extends the last_resume_reason to log suspend abort reason. The abort
reasons will have "Abort:" appended at the start to distinguish itself
from the resume reason.

Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
Change-Id: I3207f1844e3d87c706dfc298fb10e1c648814c5f
2016-02-16 13:53:38 -08:00
Ruchi Kandoi
1adb5b4034 power: Avoids bogus error messages for the suspend aborts.
Avoids printing bogus error message "tasks refusing to freeze", in cases
where pending wakeup source caused the suspend abort.

Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
Change-Id: I913ad290f501b31cd536d039834c8d24c6f16928
2016-02-16 13:53:38 -08:00
Ruchi Kandoi
4407d13a09 Power: Changes the permission to read only for sysfs file /sys/kernel/wakeup_reasons/last_resume_reason
Change-Id: I8ac568a7cb58c31decd379195de517ff3c6f9c65
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2016-02-16 13:53:37 -08:00
Greg Hackmann
5753c93191 power: wakeup_reason: rename irq_count to irqcount
On x86, irq_count conflicts with a declaration in
arch/x86/include/asm/processor.h

Change-Id: I3e4fde0ff64ef59ff5ed2adc0ea3a644641ee0b7
Signed-off-by: Greg Hackmann <ghackmann@google.com>
2016-02-16 13:53:36 -08:00
Ruchi Kandoi
617d4944c9 Power: Add guard condition for maximum wakeup reasons
Ensure the array for the wakeup reason IRQs does not overflow.

Change-Id: Iddc57a3aeb1888f39d4e7b004164611803a4d37c
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
(cherry picked from commit b5ea40cdfcf38296535f931a7e5e7bf47b6fad7f)
2016-02-16 13:53:36 -08:00
Ruchi Kandoi
93fd310cb6 POWER: fix compile warnings in log_wakeup_reason
Change I81addaf420f1338255c5d0638b0d244a99d777d1 introduced compile
warnings, fix these.

Change-Id: I05482a5335599ab96c0a088a7d175c8d4cf1cf69
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2016-02-16 13:53:35 -08:00
Ruchi Kandoi
abcb8499ac Power: add an API to log wakeup reasons
Add API log_wakeup_reason() and expose it to userspace via sysfs path
/sys/kernel/wakeup_reasons/last_resume_reason

Change-Id: I81addaf420f1338255c5d0638b0d244a99d777d1
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
2016-02-16 13:53:35 -08:00
Todd Poynor
1eff8f99f9 PM / Suspend: Print wall time at suspend entry and exit
Change-Id: I92f252414c013b018b9a392eae1ee039aa0e89dc
Signed-off-by: Todd Poynor <toddpoynor@google.com>
2016-02-16 13:53:34 -08:00
Arun Bharadwaj
a2b15c0b53 tracing/sched: Add trace events to track cpu hotplug.
Add ftrace event trace_sched_cpu_hotplug to track cpu
hot-add and hot-remove events.

This is useful in a variety of power, performance and
debug analysis scenarios.

Change-Id: I5d202c7a229ffacc3aafb7cf9afee0b0ee7b0931
Signed-off-by: Arun Bharadwaj <abharadw@codeaurora.org>
2016-02-16 13:53:29 -08:00
Dmitry Shmidt
99dd30a309 trace: fix compilation for 4.1
Change-Id: Id88b5d30847bc6d3cfe1d8cd00cbdc975c9712d1
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
2016-02-16 13:53:29 -08:00
Jamie Gennis
e33c31a091 trace: add non-hierarchical function_graph option
Add the 'funcgraph-flat' option to the function_graph tracer to use the default
trace printing format rather than the hierarchical formatting normally used.

Change-Id: If2900bfb86e6f8f51379f56da4f6fabafa630909
Signed-off-by: Jamie Gennis <jgennis@google.com>
2016-02-16 13:53:27 -08:00