Commit Graph

20228 Commits

Author SHA1 Message Date
Christoph Hellwig
343df3c79c suspend: simplify block I/O handling
Stop abusing struct page functionality and the swap end_io handler, and
instead add a modified version of the blk-lib.c bio_batch helpers.

Also move the block I/O code into swap.c as they are directly tied into
each other.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Ming Lin <mlin@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-19 09:19:59 -06:00
Shaohua Li
5596d0d591 sched: always use blk_schedule_flush_plug in io_schedule_out
block plug callback could sleep, so we introduce a parameter
'from_schedule' and corresponding drivers can use it to destinguish a
schedule plug flush or a plug finish. Unfortunately io_schedule_out
still uses blk_flush_plug(). This causes below output (Note, I added a
might_sleep() in raid1_unplug to make it trigger faster, but the whole
thing doesn't matter if I add might_sleep). In raid1/10, this can cause
deadlock.

This patch makes io_schedule_out always uses blk_schedule_flush_plug.
This should only impact drivers (as far as I know, raid 1/10) which are
sensitive to the 'from_schedule' parameter.

[  370.817949] ------------[ cut here ]------------
[  370.817960] WARNING: CPU: 7 PID: 145 at ../kernel/sched/core.c:7306 __might_sleep+0x7f/0x90()
[  370.817969] do not call blocking ops when !TASK_RUNNING; state=2 set at [<ffffffff81092fcf>] prepare_to_wait+0x2f/0x90
[  370.817971] Modules linked in: raid1
[  370.817976] CPU: 7 PID: 145 Comm: kworker/u16:9 Tainted: G        W       4.0.0+ #361
[  370.817977] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140709_153802- 04/01/2014
[  370.817983] Workqueue: writeback bdi_writeback_workfn (flush-9:1)
[  370.817985]  ffffffff81cd83be ffff8800ba8cb298 ffffffff819dd7af 0000000000000001
[  370.817988]  ffff8800ba8cb2e8 ffff8800ba8cb2d8 ffffffff81051afc ffff8800ba8cb2c8
[  370.817990]  ffffffffa00061a8 000000000000041e 0000000000000000 ffff8800ba8cba28
[  370.817993] Call Trace:
[  370.817999]  [<ffffffff819dd7af>] dump_stack+0x4f/0x7b
[  370.818002]  [<ffffffff81051afc>] warn_slowpath_common+0x8c/0xd0
[  370.818004]  [<ffffffff81051b86>] warn_slowpath_fmt+0x46/0x50
[  370.818006]  [<ffffffff81092fcf>] ? prepare_to_wait+0x2f/0x90
[  370.818008]  [<ffffffff81092fcf>] ? prepare_to_wait+0x2f/0x90
[  370.818010]  [<ffffffff810776ef>] __might_sleep+0x7f/0x90
[  370.818014]  [<ffffffffa0000c03>] raid1_unplug+0xd3/0x170 [raid1]
[  370.818024]  [<ffffffff81421d9a>] blk_flush_plug_list+0x8a/0x1e0
[  370.818028]  [<ffffffff819e3550>] ? bit_wait+0x50/0x50
[  370.818031]  [<ffffffff819e21b0>] io_schedule_timeout+0x130/0x140
[  370.818033]  [<ffffffff819e3586>] bit_wait_io+0x36/0x50
[  370.818034]  [<ffffffff819e31b5>] __wait_on_bit+0x65/0x90
[  370.818041]  [<ffffffff8125b67c>] ? ext4_read_block_bitmap_nowait+0xbc/0x630
[  370.818043]  [<ffffffff819e3550>] ? bit_wait+0x50/0x50
[  370.818045]  [<ffffffff819e3302>] out_of_line_wait_on_bit+0x72/0x80
[  370.818047]  [<ffffffff810935e0>] ? autoremove_wake_function+0x40/0x40
[  370.818050]  [<ffffffff811de744>] __wait_on_buffer+0x44/0x50
[  370.818053]  [<ffffffff8125ae80>] ext4_wait_block_bitmap+0xe0/0xf0
[  370.818058]  [<ffffffff812975d6>] ext4_mb_init_cache+0x206/0x790
[  370.818062]  [<ffffffff8114bc6c>] ? lru_cache_add+0x1c/0x50
[  370.818064]  [<ffffffff81297c7e>] ext4_mb_init_group+0x11e/0x200
[  370.818066]  [<ffffffff81298231>] ext4_mb_load_buddy+0x341/0x360
[  370.818068]  [<ffffffff8129a1a3>] ext4_mb_find_by_goal+0x93/0x2f0
[  370.818070]  [<ffffffff81295b54>] ? ext4_mb_normalize_request+0x1e4/0x5b0
[  370.818072]  [<ffffffff8129ab67>] ext4_mb_regular_allocator+0x67/0x460
[  370.818074]  [<ffffffff81295b54>] ? ext4_mb_normalize_request+0x1e4/0x5b0
[  370.818076]  [<ffffffff8129ca4b>] ext4_mb_new_blocks+0x4cb/0x620
[  370.818079]  [<ffffffff81290956>] ext4_ext_map_blocks+0x4c6/0x14d0
[  370.818081]  [<ffffffff812a4d4e>] ? ext4_es_lookup_extent+0x4e/0x290
[  370.818085]  [<ffffffff8126399d>] ext4_map_blocks+0x14d/0x4f0
[  370.818088]  [<ffffffff81266fbd>] ext4_writepages+0x76d/0xe50
[  370.818094]  [<ffffffff81149691>] do_writepages+0x21/0x50
[  370.818097]  [<ffffffff811d5c00>] __writeback_single_inode+0x60/0x490
[  370.818099]  [<ffffffff811d630a>] writeback_sb_inodes+0x2da/0x590
[  370.818103]  [<ffffffff811abf4b>] ? trylock_super+0x1b/0x50
[  370.818105]  [<ffffffff811abf4b>] ? trylock_super+0x1b/0x50
[  370.818107]  [<ffffffff811d665f>] __writeback_inodes_wb+0x9f/0xd0
[  370.818109]  [<ffffffff811d69db>] wb_writeback+0x34b/0x3c0
[  370.818111]  [<ffffffff811d70df>] bdi_writeback_workfn+0x23f/0x550
[  370.818116]  [<ffffffff8106bbd8>] process_one_work+0x1c8/0x570
[  370.818117]  [<ffffffff8106bb5b>] ? process_one_work+0x14b/0x570
[  370.818119]  [<ffffffff8106c09b>] worker_thread+0x11b/0x470
[  370.818121]  [<ffffffff8106bf80>] ? process_one_work+0x570/0x570
[  370.818124]  [<ffffffff81071868>] kthread+0xf8/0x110
[  370.818126]  [<ffffffff81071770>] ? kthread_create_on_node+0x210/0x210
[  370.818129]  [<ffffffff819e9322>] ret_from_fork+0x42/0x70
[  370.818131]  [<ffffffff81071770>] ? kthread_create_on_node+0x210/0x210
[  370.818132] ---[ end trace 7b4deb71e68b6605 ]---

V2: don't change ->in_iowait

Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-08 14:17:15 -06:00
Linus Torvalds
6c3c1eb3c3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Receive packet length needs to be adjust by 2 on RX to accomodate
    the two padding bytes in altera_tse driver.  From Vlastimil Setka.

 2) If rx frame is dropped due to out of memory in macb driver, we leave
    the receive ring descriptors in an undefined state.  From Punnaiah
    Choudary Kalluri

 3) Some netlink subsystems erroneously signal NLM_F_MULTI.  That is
    only for dumps.  Fix from Nicolas Dichtel.

 4) Fix mis-use of raw rt->rt_pmtu value in ipv4, one must always go via
    the ipv4_mtu() helper.  From Herbert Xu.

 5) Fix null deref in bridge netfilter, and miscalculated lengths in
    jump/goto nf_tables verdicts.  From Florian Westphal.

 6) Unhash ping sockets properly.

 7) Software implementation of BPF divide did 64/32 rather than 64/64
    bit divide.  The JITs got it right.  Fix from Alexei Starovoitov.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (30 commits)
  ipv4: Missing sk_nulls_node_init() in ping_unhash().
  net: fec: Fix RGMII-ID mode
  net/mlx4_en: Schedule napi when RX buffers allocation fails
  netxen_nic: use spin_[un]lock_bh around tx_clean_lock
  net/mlx4_core: Fix unaligned accesses
  mlx4_en: Use correct loop cursor in error path.
  cxgb4: Fix MC1 memory offset calculation
  bnx2x: Delay during kdump load
  net: Fix Kernel Panic in bonding driver debugfs file: rlb_hash_table
  net: dsa: Fix scope of eeprom-length property
  net: macb: Fix race condition in driver when Rx frame is dropped
  hv_netvsc: Fix a bug in netvsc_start_xmit()
  altera_tse: Correct rx packet length
  mlx4: Fix tx ring affinity_mask creation
  tipc: fix problem with parallel link synchronization mechanism
  tipc: remove wrong use of NLM_F_MULTI
  bridge/nl: remove wrong use of NLM_F_MULTI
  bridge/mdb: remove wrong use of NLM_F_MULTI
  net: sched: act_connmark: don't zap skb->nfct
  trivial: net: systemport: bcmsysport.h: fix 0x0x prefix
  ...
2015-05-01 20:51:04 -07:00
Linus Torvalds
4a152c3913 Power management and ACPI fixes for v4.1-rc2
- Fix for a regression in the cpuidle core introduced by one of
    the recent commits in the clockevents_notify() removal series
    that put a call to a function which had to be executed with
    disabled interrupts into a code path running with enabled
    interrupts (Rafael J Wysocki).
 
  - Fix for a build problem in ACPICA (with GCC 4.5) introduced by one
    of the recent ACPICA tools commits that added a duplicate typedef
    to one of the ACPICA's header files by mistake (Olaf Hering).
 
  - Fix for a regression in the ACPI SBS (Smart Battery Subsystem)
    driver introduced during the 3.18 development cycle causing the
    smart battery manager to be marked as not present when it should
    be marked as present (Chris Bainbridge).
 
 /
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Merge tag 'pm+acpi-4.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI fixes from Rafael Wysocki:
 "Three regression fixes this time, one for a recent regression in the
  cpuidle core affecting multiple systems, one for an inadvertently
  added duplicate typedef in ACPICA that breaks compilation with GCC 4.5
  and one for an ACPI Smart Battery Subsystem driver regression
  introduced during the 3.18 cycle (stable-candidate).

  Specifics:

   - Fix for a regression in the cpuidle core introduced by one of the
     recent commits in the clockevents_notify() removal series that put
     a call to a function which had to be executed with disabled
     interrupts into a code path running with enabled interrupts (Rafael
     J Wysocki)

   - Fix for a build problem in ACPICA (with GCC 4.5) introduced by one
     of the recent ACPICA tools commits that added a duplicate typedef
     to one of the ACPICA's header files by mistake (Olaf Hering)

   - Fix for a regression in the ACPI SBS (Smart Battery Subsystem)
     driver introduced during the 3.18 development cycle causing the
     smart battery manager to be marked as not present when it should be
     marked as present (Chris Bainbridge)"

* tag 'pm+acpi-4.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle: Run tick_broadcast_exit() with disabled interrupts
  ACPI / SBS: Enable battery manager when present
  ACPICA: remove duplicate u8 typedef
2015-04-30 14:23:31 -07:00
Linus Torvalds
9dbbe3cfc3 Remove from guest code the handling of task migration during a
pvclock read; instead use the correct protocol in KVM.
 
 This removes the need for task migration notifiers in core
 scheduler code.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm changes from Paolo Bonzini:
 "Remove from guest code the handling of task migration during a pvclock
  read; instead use the correct protocol in KVM.

  This removes the need for task migration notifiers in core scheduler
  code"

[ The scheduler people really hated the migration notifiers, so this was
  kind of required  - Linus ]

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  x86: pvclock: Really remove the sched notifier for cross-cpu migrations
  kvm: x86: fix kvmclock update protocol
2015-04-30 09:44:04 -07:00
David Howells
9c4249c8e0 modsign: change default key details
Change default key details to be more obviously unspecified.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-30 09:35:41 -07:00
Rafael J. Wysocki
df8d9eeadd cpuidle: Run tick_broadcast_exit() with disabled interrupts
Commit 335f49196f (sched/idle: Use explicit broadcast oneshot
control function) replaced clockevents_notify() invocations in
cpuidle_idle_call() with direct calls to tick_broadcast_enter()
and tick_broadcast_exit(), but it overlooked the fact that
interrupts were already enabled before calling the latter which
led to functional breakage on systems using idle states with the
CPUIDLE_FLAG_TIMER_STOP flag set.

Fix that by moving the invocations of tick_broadcast_enter()
and tick_broadcast_exit() down into cpuidle_enter_state() where
interrupts are still disabled when tick_broadcast_exit() is
called.  Also ensure that interrupts will be disabled before
running tick_broadcast_exit() even if they have been enabled by
the idle state's ->enter callback.  Trigger a WARN_ON_ONCE() in
that case, as we generally don't want that to happen for states
with CPUIDLE_FLAG_TIMER_STOP set.

Fixes: 335f49196f (sched/idle: Use explicit broadcast oneshot control function)
Reported-and-tested-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-29 15:19:21 +02:00
Linus Torvalds
14bc84ce0b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "One additional new feature for 4.1, a new PRNG based on SHA-512 for
  the zcrypt driver.

  Two memory management related changes, the page table reallocation for
  KVM is removed, and with file ptes gone the encoding of page table
  entries is improved.

  And three bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/zcrypt: Introduce new SHA-512 based Pseudo Random Generator.
  s390/mm: change swap pte encoding and pgtable cleanup
  s390/mm: correct transfer of dirty & young bits in __pmd_to_pte
  s390/bpf: add dependency to z196 features
  s390/3215: free memory in error path
  s390/kvm: remove delayed reallocation of page tables for KVM
  kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFP
2015-04-28 09:58:46 -07:00
Alexei Starovoitov
876a7ae65b bpf: fix 64-bit divide
ALU64_DIV instruction should be dividing 64-bit by 64-bit,
whereas do_div() does 64-bit by 32-bit divide.
x64 and arm64 JITs correctly implement 64 by 64 unsigned divide.
llvm BPF backend emits code assuming that ALU64_DIV does 64 by 64.

Fixes: 89aa075832 ("net: sock: allow eBPF programs to be attached to sockets")
Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-27 23:11:49 -04:00
Paolo Bonzini
73459e2a1a x86: pvclock: Really remove the sched notifier for cross-cpu migrations
This reverts commits 0a4e6be9ca
and 80f7fdb1c7.

The task migration notifier was originally introduced in order to support
the pvclock vsyscall with non-synchronized TSC, but KVM only supports it
with synchronized TSC.  Hence, on KVM the race condition is only needed
due to a bad implementation on the host side, and even then it's so rare
that it's mostly theoretical.

As far as KVM is concerned it's possible to fix the host, avoiding the
additional complexity in the vDSO and the (re)introduction of the task
migration notifier.

Xen, on the other hand, hasn't yet implemented vsyscall support at
all, so we do not care about its plans for non-synchronized TSC.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-27 15:49:30 +02:00
Linus Torvalds
9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Martin Schwidefsky
7e01b5acd8 kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFP
Introduce KEXEC_CONTROL_MEMORY_GFP to allow the architecture code
to override the gfp flags of the allocation for the kexec control
page. The loop in kimage_alloc_normal_control_pages allocates pages
with GFP_KERNEL until a page is found that happens to have an
address smaller than the KEXEC_CONTROL_MEMORY_LIMIT. On systems
with a large memory size but a small KEXEC_CONTROL_MEMORY_LIMIT
the loop will keep allocating memory until the oom killer steps in.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-23 16:52:01 +02:00
Linus Torvalds
27cf3a16b2 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit fixes from Paul Moore:
 "Seven audit patches for v4.1, all bug fixes.

  The largest, and perhaps most significant commit helps resolve some
  memory pressure issues related to the inode cache and audit, there are
  also a few small commits which help resolve some timing issues with
  the audit log queue, and the rest fall into the always popular "code
  clean-up" category.

  In general, nothing really substantial, just a nice set of maintenance
  patches"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  audit: Remove condition which always evaluates to false
  audit: reduce mmap_sem hold for mm->exe_file
  audit: consolidate handling of mm->exe_file
  audit: code clean up
  audit: don't reset working wait time accidentally with auditd
  audit: don't lose set wait time on first successful call to audit_log_start()
  audit: move the tree pruning to a dedicated thread
2015-04-22 14:49:23 -07:00
Linus Torvalds
4f2112351b This adds three fixes for the tracing code.
The first is a bug when ftrace_dump_on_oops is triggered in atomic context
 and function graph tracer is the tracer that is being reported.
 
 The second fix is bad parsing of the trace_events from the kernel
 command line, where it would ignore specific events if the system
 name is used with defining the event(it enables all events within the
 system).
 
 The last one is a fix to the TRACE_DEFINE_ENUM(), where a check was missing
 to see if the ptr was incremented to the end of the string, but the loop
 increments it again and can miss the nul delimiter to stop processing.
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Merge tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This adds three fixes for the tracing code.

  The first is a bug when ftrace_dump_on_oops is triggered in atomic
  context and function graph tracer is the tracer that is being
  reported.

  The second fix is bad parsing of the trace_events from the kernel
  command line, where it would ignore specific events if the system name
  is used with defining the event(it enables all events within the
  system).

  The last one is a fix to the TRACE_DEFINE_ENUM(), where a check was
  missing to see if the ptr was incremented to the end of the string,
  but the loop increments it again and can miss the nul delimiter to
  stop processing"

* tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix possible out of bounds memory access when parsing enums
  tracing: Fix incorrect enabling of trace events by boot cmdline
  tracing: Handle ftrace_dump() atomic context in graph_trace_open()
2015-04-22 11:27:36 -07:00
Linus Torvalds
15ce2658dd Quentin opened a can of worms by adding extable entry checking to modpost,
but most architectures seem fixed now.  Thanks to all involved.
 
 Last minute rebase because I noticed a "[PATCH]" had snuck into a commit
 message somehow.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Quentin opened a can of worms by adding extable entry checking to
  modpost, but most architectures seem fixed now.  Thanks to all
  involved.

  Last minute rebase because I noticed a "[PATCH]" had snuck into a
  commit message somehow"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: don't emit section mismatch warnings for compiler optimizations
  modpost: expand pattern matching to support substring matches
  modpost: do not try to match the SHT_NUL section.
  modpost: fix extable entry size calculation.
  modpost: fix inverted logic in is_extable_fault_address().
  modpost: handle -ffunction-sections
  modpost: Whitelist .text.fixup and .exception.text
  params: handle quotes properly for values not of form foo="bar".
  modpost: document the use of struct section_check.
  modpost: handle relocations mismatch in __ex_table.
  scripts: add check_extable.sh script.
  modpost: mismatch_handler: retrieve tosym information only when needed.
  modpost: factorize symbol pretty print in get_pretty_name().
  modpost: add handler function pointer to sectioncheck.
  modpost: add .sched.text and .kprobes.text to the TEXT_SECTIONS list.
  modpost: add strict white-listing when referencing sections.
  module: do not print allocation-fail warning on bogus user buffer size
  kernel/module.c: fix typos in message about unused symbols
2015-04-22 09:49:24 -07:00
Linus Torvalds
1fc149933f Char/Misc driver patches for 4.1-rc1
Here's the big char/misc driver patchset for 4.1-rc1.
 
 Lots of different driver subsystem updates here, nothing major, full
 details are in the shortlog below.
 
 All of this has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here's the big char/misc driver patchset for 4.1-rc1.

  Lots of different driver subsystem updates here, nothing major, full
  details are in the shortlog.

  All of this has been in linux-next for a while"

* tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (133 commits)
  mei: trace: remove unused TRACE_SYSTEM_STRING
  DTS: ARM: OMAP3-N900: Add lis3lv02d support
  Documentation: DT: lis302: update wakeup binding
  lis3lv02d: DT: add wakeup unit 2 and wakeup threshold
  lis3lv02d: DT: use s32 to support negative values
  Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case
  Drivers: hv: hv_balloon: correctly handle val.freeram<num_pages case
  mei: replace check for connection instead of transitioning
  mei: use mei_cl_is_connected consistently
  mei: fix mei_poll operation
  hv_vmbus: Add gradually increased delay for retries in vmbus_post_msg()
  Drivers: hv: hv_balloon: survive ballooning request with num_pages=0
  Drivers: hv: hv_balloon: eliminate jumps in piecewiese linear floor function
  Drivers: hv: hv_balloon: do not online pages in offline blocks
  hv: remove the per-channel workqueue
  hv: don't schedule new works in vmbus_onoffer()/vmbus_onoffer_rescind()
  hv: run non-blocking message handlers in the dispatch tasklet
  coresight: moving to new "hwtracing" directory
  coresight-tmc: Adding a status interface to sysfs
  coresight: remove the unnecessary configuration coresight-default-sink
  ...
2015-04-21 09:42:58 -07:00
Linus Torvalds
41d5e08ea8 TTY/Serial patches for 4.1-rc1
Here's the big tty/serial driver update for 4.1-rc1.
 
 It was delayed for a bit due to some questions surrounding some of the
 console command line parsing changes that are in here.  There's still
 one tiny regression for people who were previously putting multiple
 console command lines and expecting them all to be ignored for some odd
 reason, but Peter is working on fixing that.  If not, I'll send a revert
 for the offending patch, but I have faith that Peter can address it.
 
 Other than the console work here, there's the usual serial driver
 updates and changes, and a buch of 8250 reworks to try to make that
 driver easier to maintain over time, and have it support more devices in
 the future.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here's the big tty/serial driver update for 4.1-rc1.

  It was delayed for a bit due to some questions surrounding some of the
  console command line parsing changes that are in here.  There's still
  one tiny regression for people who were previously putting multiple
  console command lines and expecting them all to be ignored for some
  odd reason, but Peter is working on fixing that.  If not, I'll send a
  revert for the offending patch, but I have faith that Peter can
  address it.

  Other than the console work here, there's the usual serial driver
  updates and changes, and a buch of 8250 reworks to try to make that
  driver easier to maintain over time, and have it support more devices
  in the future.

  All of these have been in linux-next for a while"

* tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits)
  n_gsm: Drop unneeded cast on netdev_priv
  sc16is7xx: expose RTS inversion in RS-485 mode
  serial: 8250_pci: port failed after wakeup from S3
  earlycon: 8250: Document kernel command line options
  earlycon: 8250: Fix command line regression
  earlycon: Fix __earlycon_table stride
  tty: clean up the tty time logic a bit
  serial: 8250_dw: only get the clock rate in one place
  serial: 8250_dw: remove useless ACPI ID check
  dmaengine: hsu: move memory allocation to GFP_NOWAIT
  dmaengine: hsu: remove redundant pieces of code
  serial: 8250_pci: add Intel Tangier support
  dmaengine: hsu: add Intel Tangier PCI ID
  serial: 8250_pci: replace switch-case by formula for Intel MID
  serial: 8250_pci: replace switch-case by formula
  tty: cpm_uart: replace CONFIG_8xx by CONFIG_CPM1
  serial: jsm: some off by one bugs
  serial: xuartps: Fix check in console_setup().
  serial: xuartps: Get rid of register access macros.
  serial: xuartps: Fix iobase use.
  ...
2015-04-21 09:33:10 -07:00
Linus Torvalds
5224b9613b smp: Fix error case handling in smp_call_function_*()
Commit 8053871d0f ("smp: Fix smp_call_function_single_async()
locking") fixed the locking for the asynchronous smp-call case, but in
the process of moving the lock handling around, one of the error cases
ended up not unlocking the call data at all.

This went unnoticed on x86, because this is a "caller is buggy" case,
where the caller is trying to call a non-existent CPU.  But apparently
ARM does that (at least under qemu-arm).  Bindly doing cross-cpu calls
to random CPU's that aren't even online seems a bit fishy, but the error
handling was clearly not correct.

Simply add the missing "csd_unlock()" to the error path.

Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Analyzed-by: Rabin Vincent <rabin@rab.in>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-19 13:19:23 -07:00
Linus Torvalds
396c9df223 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Two fixes: an smp-call fix and a lockdep fix"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Fix smp_call_function_single_async() locking
  lockdep: Make print_lock() robust against concurrent release
2015-04-18 11:23:42 -04:00
Linus Torvalds
388f997620 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix verifier memory corruption and other bugs in BPF layer, from
    Alexei Starovoitov.

 2) Add a conservative fix for doing BPF properly in the BPF classifier
    of the packet scheduler on ingress.  Also from Alexei.

 3) The SKB scrubber should not clear out the packet MARK and security
    label, from Herbert Xu.

 4) Fix oops on rmmod in stmmac driver, from Bryan O'Donoghue.

 5) Pause handling is not correct in the stmmac driver because it
    doesn't take into consideration the RX and TX fifo sizes.  From
    Vince Bridgers.

 6) Failure path missing unlock in FOU driver, from Wang Cong.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
  net: dsa: use DEVICE_ATTR_RW to declare temp1_max
  netns: remove BUG_ONs from net_generic()
  IB/ipoib: Fix ndo_get_iflink
  sfc: Fix memcpy() with const destination compiler warning.
  altera tse: Fix network-delays and -retransmissions after high throughput.
  net: remove unused 'dev' argument from netif_needs_gso()
  act_mirred: Fix bogus header when redirecting from VLAN
  inet_diag: fix access to tcp cc information
  tcp: tcp_get_info() should fetch socket fields once
  net: dsa: mv88e6xxx: Add missing initialization in mv88e6xxx_set_port_state()
  skbuff: Do not scrub skb mark within the same name space
  Revert "net: Reset secmark when scrubbing packet"
  bpf: fix two bugs in verification logic when accessing 'ctx' pointer
  bpf: fix bpf helpers to use skb->mac_header relative offsets
  stmmac: Configure Flow Control to work correctly based on rxfifo size
  stmmac: Enable unicast pause frame detect in GMAC Register 6
  stmmac: Read tx-fifo-depth and rx-fifo-depth from the devicetree
  stmmac: Add defines and documentation for enabling flow control
  stmmac: Add properties for transmit and receive fifo sizes
  stmmac: fix oops on rmmod after assigning ip addr
  ...
2015-04-17 16:31:08 -04:00
Steven Rostedt (Red Hat)
3193899d4d tracing: Fix possible out of bounds memory access when parsing enums
The code that replaces the enum names with the enum values in the
tracepoints' format files could possible miss the end of string nul
character. This was caused by processing things like backslashes, quotes
and other tokens. After processing the tokens, a check for the nul
character needed to be done before continuing the loop, because the loop
incremented the pointer before doing the check, which could bypass the nul
character.

Link: http://lkml.kernel.org/r/552E661D.5060502@oracle.com

Reported-by: Sasha Levin <sasha.levin@oracle.com> # via KASan
Tested-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Fixes: 0c564a538a "tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values"
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-17 10:34:43 -04:00
Davidlohr Bueso
11163348a2 oprofile: reduce mmap_sem hold for mm->exe_file
sync_buffer() needs the mmap_sem for two distinct operations, both only
occurring upon user context switch handling:

 1) Dealing with the exe_file.

 2) Adding the dcookie data as we need to lookup the vma that
   backs it. This is done via add_sample() and add_data().

This patch isolates 1), for it will no longer need the mmap_sem for
serialization.  However, for now, make of the more standard
get_mm_exe_file(), requiring only holding the mmap_sem to read the value,
and relying on reference counting to make sure that the exe file won't
dissappear underneath us while doing the get dcookie.

As a consequence, for 2) we move the mmap_sem locking into where we really
need it, in lookup_dcookie().  The benefits are twofold: reduce mmap_sem
hold times, and cleaner code.

[akpm@linux-foundation.org: export get_mm_exe_file for arch/x86/oprofile/oprofile.ko]
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Robert Richter <rric@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:11 -04:00
Andrey Ryabinin
9d796e6623 gcov: fix softlockups
gcov profiling if enabled with other heavy compile-time instrumentation
like KASan could trigger following softlockups:

  NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]
  Modules linked in:
  irq event stamp: 22823276
  hardirqs last  enabled at (22823275): [<ffffffff86e8d10d>] mutex_lock_nested+0x7d9/0x930
  hardirqs last disabled at (22823276): [<ffffffff86e9521d>] apic_timer_interrupt+0x6d/0x80
  softirqs last  enabled at (22823172): [<ffffffff811ed969>] __do_softirq+0x4db/0x729
  softirqs last disabled at (22823167): [<ffffffff811edfcf>] irq_exit+0x7d/0x15b
  CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W       3.19.0-05245-gbb33326-dirty #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5.1-0-g8936dbb-20141113_115728-nilsson.home.kraxel.org 04/01/2014
  task: ffff88006cba8000 ti: ffff88006cbb0000 task.ti: ffff88006cbb0000
  RIP: kasan_mem_to_shadow+0x1e/0x1f
  Call Trace:
    strcmp+0x28/0x70
    get_node_by_name+0x66/0x99
    gcov_event+0x4f/0x69e
    gcov_enable_events+0x54/0x7b
    gcov_fs_init+0xf8/0x134
    do_one_initcall+0x1b2/0x288
    kernel_init_freeable+0x467/0x580
    kernel_init+0x15/0x18b
    ret_from_fork+0x7c/0xb0
  Kernel panic - not syncing: softlockup: hung tasks

Fix this by sticking cond_resched() in gcov_enable_events().

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:08 -04:00
Heinrich Schuchardt
230633d109 kernel/sysctl.c: detect overflows when converting to int
When converting unsigned long to int overflows may occur.  These currently
are not detected when writing to the sysctl file system.

E.g. on a system where int has 32 bits and long has 64 bits
  echo 0x800001234 > /proc/sys/kernel/threads-max
has the same effect as
  echo 0x1234 > /proc/sys/kernel/threads-max

The patch adds the missing check in do_proc_dointvec_conv.

With the patch an overflow will result in an error EINVAL when writing to
the the sysctl file system.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:08 -04:00
Davidlohr Bueso
6e399cd144 prctl: avoid using mmap_sem for exe_file serialization
Oleg cleverly suggested using xchg() to set the new mm->exe_file instead
of calling set_mm_exe_file() which requires some form of serialization --
mmap_sem in this case.  For archs that do not have atomic rmw instructions
we still fallback to a spinlock alternative, so this should always be
safe.  As such, we only need the mmap_sem for looking up the backing
vm_file, which can be done sharing the lock.  Naturally, this means we
need to manually deal with both the new and old file reference counting,
and we need not worry about the MMF_EXE_FILE_CHANGED bits, which can
probably be deleted in the future anyway.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:07 -04:00
Konstantin Khlebnikov
90f31d0ea8 mm: rcu-protected get_mm_exe_file()
This patch removes mm->mmap_sem from mm->exe_file read side.
Also it kills dup_mm_exe_file() and moves exe_file duplication into
dup_mmap() where both mmap_sems are locked.

[akpm@linux-foundation.org: fix comment typo]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:07 -04:00
Heinrich Schuchardt
16db3d3f11 kernel/sysctl.c: threads-max observe limits
Users can change the maximum number of threads by writing to
/proc/sys/kernel/threads-max.

With the patch the value entered is checked against the same limits that
apply when fork_init is called.

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>
2015-04-17 09:04:07 -04:00
Heinrich Schuchardt
ac1b398de1 kernel/fork.c: avoid division by zero
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 32-bit calculation there is no solution which delivers valid results
for all possible combinations of the parameters.  The code is only called
once.  Hence a 64-bit calculation can be used as solution.

[akpm@linux-foundation.org: use clamp_t(), per Oleg]
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>
2015-04-17 09:04:07 -04:00
Heinrich Schuchardt
ff691f6e03 kernel/fork.c: new function for max_threads
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>
2015-04-17 09:04:06 -04:00
Jean Delvare
3ea7f5e25e fork_init: update max_threads comment
The comment explaining what value max_threads is set to is outdated.  The
maximum memory consumption ratio for thread structures was 1/2 until
February 2002, then it was briefly changed to 1/16 before being set to 1/8
which we still use today.  The comment was never updated to reflect that
change, it's about time.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:06 -04:00
Michal Hocko
35f71bc0a0 fork: report pid reservation failure properly
copy_process will report any failure in alloc_pid as ENOMEM currently
which is misleading because the pid allocation might fail not only when
the memory is short but also when the pid space is consumed already.

The current man page even mentions this case:

: EAGAIN
:
:       A system-imposed limit on the number of threads was encountered.
:       There are a number of limits that may trigger this error: the
:       RLIMIT_NPROC soft resource limit (set via setrlimit(2)), which
:       limits the number of processes and threads for a real user ID, was
:       reached; the kernel's system-wide limit on the number of processes
:       and threads, /proc/sys/kernel/threads-max, was reached (see
:       proc(5)); or the maximum number of PIDs, /proc/sys/kernel/pid_max,
:       was reached (see proc(5)).

so the current behavior is also incorrect wrt.  documentation.  POSIX man
page also suggest returing EAGAIN when the process count limit is reached.

This patch simply propagates error code from alloc_pid and makes sure we
return -EAGAIN due to reservation failure.  This will make behavior of
fork closer to both our documentation and POSIX.

alloc_pid might alsoo fail when the reaper in the pid namespace is dead
(the namespace basically disallows all new processes) and there is no
good error code which would match documented ones. We have traditionally
returned ENOMEM for this case which is misleading as well but as per
Eric W. Biederman this behavior is documented in man pid_namespaces(7)

: If the "init" process of a PID namespace terminates, the kernel
: terminates all of the processes in the namespace via a SIGKILL signal.
: This behavior reflects the fact that the "init" process is essential for
: the correct operation of a PID namespace.  In this case, a subsequent
: fork(2) into this PID namespace will fail with the error ENOMEM; it is
: not possible to create a new processes in a PID namespace whose "init"
: process has terminated.

and introducing a new error code would be too risky so let's stick to
ENOMEM for this case.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:06 -04:00
Vladimir Davydov
69828dce7a signal: remove warning about using SI_TKILL in rt_[tg]sigqueueinfo
Sending SI_TKILL from rt_[tg]sigqueueinfo was deprecated, so now we issue
a warning on the first attempt of doing it.  We use WARN_ON_ONCE, which is
not informative and, what is worse, taints the kernel, making the trinity
syscall fuzzer complain false-positively from time to time.

It does not look like we need this warning at all, because the behaviour
changed quite a long time ago (2.6.39), and if an application relies on
the old API, it gets EPERM anyway and can issue a warning by itself.

So let us zap the warning in kernel.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:06 -04:00
Oleg Nesterov
64a4096c5c ptrace: ptrace_detach() can no longer race with SIGKILL
ptrace_detach() re-checks ->ptrace under tasklist lock and calls
release_task() if __ptrace_detach() returns true.  This was needed because
the __TASK_TRACED tracee could be killed/untraced, and it could even pass
exit_notify() before we take tasklist_lock.

But this is no longer possible after 9899d11f65 "ptrace: ensure
arch_ptrace/ptrace_request can never race with SIGKILL".  We can turn
these checks into WARN_ON() and remove release_task().

While at it, document the setting of child->exit_code.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Labath <labath@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:06 -04:00
Oleg Nesterov
b72c186999 ptrace: fix race between ptrace_resume() and wait_task_stopped()
ptrace_resume() is called when the tracee is still __TASK_TRACED.  We set
tracee->exit_code and then wake_up_state() changes tracee->state.  If the
tracer's sub-thread does wait() in between, task_stopped_code(ptrace => T)
wrongly looks like another report from tracee.

This confuses debugger, and since wait_task_stopped() clears ->exit_code
the tracee can miss a signal.

Test-case:

	#include <stdio.h>
	#include <unistd.h>
	#include <sys/wait.h>
	#include <sys/ptrace.h>
	#include <pthread.h>
	#include <assert.h>

	int pid;

	void *waiter(void *arg)
	{
		int stat;

		for (;;) {
			assert(pid == wait(&stat));
			assert(WIFSTOPPED(stat));
			if (WSTOPSIG(stat) == SIGHUP)
				continue;

			assert(WSTOPSIG(stat) == SIGCONT);
			printf("ERR! extra/wrong report:%x\n", stat);
		}
	}

	int main(void)
	{
		pthread_t thread;

		pid = fork();
		if (!pid) {
			assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0);
			for (;;)
				kill(getpid(), SIGHUP);
		}

		assert(pthread_create(&thread, NULL, waiter, NULL) == 0);

		for (;;)
			ptrace(PTRACE_CONT, pid, 0, SIGCONT);

		return 0;
	}

Note for stable: the bug is very old, but without 9899d11f65 "ptrace:
ensure arch_ptrace/ptrace_request can never race with SIGKILL" the fix
should use lock_task_sighand(child).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Pavel Labath <labath@google.com>
Tested-by: Pavel Labath <labath@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:06 -04:00
Linus Torvalds
8053871d0f smp: Fix smp_call_function_single_async() locking
The current smp_function_call code suffers a number of problems, most
notably smp_call_function_single_async() is broken.

The problem is that flush_smp_call_function_queue() does csd_unlock()
_after_ calling csd->func(). This means that a caller cannot properly
synchronize the csd usage as it has to.

Change the code to release the csd before calling ->func() for the
async case, and put a WARN_ON_ONCE(csd->flags & CSD_FLAG_LOCK) in
smp_call_function_single_async() to warn us of improper serialization,
because any waiting there can results in deadlocks when called with
IRQs disabled.

Rename the (currently) unused WAIT flag to SYNCHRONOUS and (re)use it
such that we know what to do in flush_smp_call_function_queue().

Rework csd_{,un}lock() to use smp_load_acquire() / smp_store_release()
to avoid some full barriers while more clearly providing lock
semantics.

Finally move the csd maintenance out of generic_exec_single() into its
callers for clearer code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ Added changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rafael David Tinoco <inaddy@ubuntu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CA+55aFz492bzLFhdbKN-Hygjcreup7CjMEYk3nTSfRWjppz-OA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:57:52 +02:00
Peter Zijlstra
d7bc3197b4 lockdep: Make print_lock() robust against concurrent release
During sysrq's show-held-locks command it is possible that
hlock_class() returns NULL for a given lock. The result is then (after
the warning):

	|BUG: unable to handle kernel NULL pointer dereference at 0000001c
	|IP: [<c1088145>] get_usage_chars+0x5/0x100
	|Call Trace:
	| [<c1088263>] print_lock_name+0x23/0x60
	| [<c1576b57>] print_lock+0x5d/0x7e
	| [<c1088314>] lockdep_print_held_locks+0x74/0xe0
	| [<c1088652>] debug_show_all_locks+0x132/0x1b0
	| [<c1315c48>] sysrq_handle_showlocks+0x8/0x10

This *might* happen because the thread on the other CPU drops the lock
after we are looking ->lockdep_depth and ->held_locks points no longer
to a lock that is held.

The fix here is to simply ignore it and continue.

Reported-by: Andreas Messerschmid <andreas@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17 09:42:14 +02:00
Alexei Starovoitov
725f9dcd58 bpf: fix two bugs in verification logic when accessing 'ctx' pointer
1.
first bug is a silly mistake. It broke tracing examples and prevented
simple bpf programs from loading.

In the following code:
if (insn->imm == 0 && BPF_SIZE(insn->code) == BPF_W) {
} else if (...) {
  // this part should have been executed when
  // insn->code == BPF_W and insn->imm != 0
}

Obviously it's not doing that. So simple instructions like:
r2 = *(u64 *)(r1 + 8)
will be rejected. Note the comments in the code around these branches
were and still valid and indicate the true intent.

Replace it with:
if (BPF_SIZE(insn->code) != BPF_W)
  continue;

if (insn->imm == 0) {
} else if (...) {
  // now this code will be executed when
  // insn->code == BPF_W and insn->imm != 0
}

2.
second bug is more subtle.
If malicious code is using the same dest register as source register,
the checks designed to prevent the same instruction to be used with different
pointer types will fail to trigger, since we were assigning src_reg_type
when it was already overwritten by check_mem_access().
The fix is trivial. Just move line:
src_reg_type = regs[insn->src_reg].type;
before check_mem_access().
Add new 'access skb fields bad4' test to check this case.

Fixes: 9bac3d6d54 ("bpf: allow extended BPF programs access skb fields")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-16 14:08:49 -04:00
Alexei Starovoitov
c3de6317d7 bpf: fix verifier memory corruption
Due to missing bounds check the DAG pass of the BPF verifier can corrupt
the memory which can cause random crashes during program loading:

[8.449451] BUG: unable to handle kernel paging request at ffffffffffffffff
[8.451293] IP: [<ffffffff811de33d>] kmem_cache_alloc_trace+0x8d/0x2f0
[8.452329] Oops: 0000 [#1] SMP
[8.452329] Call Trace:
[8.452329]  [<ffffffff8116cc82>] bpf_check+0x852/0x2000
[8.452329]  [<ffffffff8116b7e4>] bpf_prog_load+0x1e4/0x310
[8.452329]  [<ffffffff811b190f>] ? might_fault+0x5f/0xb0
[8.452329]  [<ffffffff8116c206>] SyS_bpf+0x806/0xa30

Fixes: f1bca824da ("bpf: add search pruning optimization to verifier")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-16 12:06:11 -04:00
Joonsoo Kim
84fce9db4d tracing: Fix incorrect enabling of trace events by boot cmdline
There is a problem that trace events are not properly enabled with
boot cmdline. The problem is that if we pass "trace_event=kmem:mm_page_alloc"
to the boot cmdline, it enables all kmem trace events, and not just
the page_alloc event.

This is caused by the parsing mechanism. When we parse the cmdline, the buffer
contents is modified due to tokenization. And, if we use this buffer
again, we will get the wrong result.

Unfortunately, this buffer is be accessed three times to set trace events
properly at boot time. So, we need to handle this situation.

There is already code handling ",", but we need another for ":".
This patch adds it.

Link: http://lkml.kernel.org/r/1429159484-22977-1-git-send-email-iamjoonsoo.kim@lge.com

Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
[ added missing return ret; ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-16 09:44:07 -04:00
Rabin Vincent
ef99b88b16 tracing: Handle ftrace_dump() atomic context in graph_trace_open()
graph_trace_open() can be called in atomic context from ftrace_dump().
Use GFP_ATOMIC for the memory allocations when that's the case, in order
to avoid the following splat.

 BUG: sleeping function called from invalid context at mm/slab.c:2849
 in_atomic(): 1, irqs_disabled(): 128, pid: 0, name: swapper/0
 Backtrace:
 ..
 [<8004dc94>] (__might_sleep) from [<801371f4>] (kmem_cache_alloc_trace+0x160/0x238)
  r7:87800040 r6:000080d0 r5:810d16e8 r4:000080d0
 [<80137094>] (kmem_cache_alloc_trace) from [<800cbd60>] (graph_trace_open+0x30/0xd0)
  r10:00000100 r9:809171a8 r8:00008e28 r7:810d16f0 r6:00000001 r5:810d16e8
  r4:810d16f0
 [<800cbd30>] (graph_trace_open) from [<800c79c4>] (trace_init_global_iter+0x50/0x9c)
  r8:00008e28 r7:808c853c r6:00000001 r5:810d16e8 r4:810d16f0 r3:800cbd30
 [<800c7974>] (trace_init_global_iter) from [<800c7aa0>] (ftrace_dump+0x90/0x2ec)
  r4:810d2580 r3:00000000
 [<800c7a10>] (ftrace_dump) from [<80414b2c>] (sysrq_ftrace_dump+0x1c/0x20)
  r10:00000100 r9:809171a8 r8:808f6e7c r7:00000001 r6:00000007 r5:0000007a
  r4:808d5394
 [<80414b10>] (sysrq_ftrace_dump) from [<800169b8>] (return_to_handler+0x0/0x18)
 [<80415498>] (__handle_sysrq) from [<800169b8>] (return_to_handler+0x0/0x18)
  r8:808c8100 r7:808c8444 r6:00000101 r5:00000010 r4:84eb3210
 [<80415668>] (handle_sysrq) from [<800169b8>] (return_to_handler+0x0/0x18)
 [<8042a760>] (pl011_int) from [<800169b8>] (return_to_handler+0x0/0x18)
  r10:809171bc r9:809171a8 r8:00000001 r7:00000026 r6:808c6000 r5:84f01e60
  r4:8454fe00
 [<8007782c>] (handle_irq_event_percpu) from [<80077b44>] (handle_irq_event+0x4c/0x6c)
  r10:808c7ef0 r9:87283e00 r8:00000001 r7:00000000 r6:8454fe00 r5:84f01e60
  r4:84f01e00
 [<80077af8>] (handle_irq_event) from [<8007aa28>] (handle_fasteoi_irq+0xf0/0x1ac)
  r6:808f52a4 r5:84f01e60 r4:84f01e00 r3:00000000
 [<8007a938>] (handle_fasteoi_irq) from [<80076dc0>] (generic_handle_irq+0x3c/0x4c)
  r6:00000026 r5:00000000 r4:00000026 r3:8007a938
 [<80076d84>] (generic_handle_irq) from [<80077128>] (__handle_domain_irq+0x8c/0xfc)
  r4:808c1e38 r3:0000002e
 [<8007709c>] (__handle_domain_irq) from [<800087b8>] (gic_handle_irq+0x34/0x6c)
  r10:80917748 r9:00000001 r8:88802100 r7:808c7ef0 r6:808c8fb0 r5:00000015
  r4:8880210c r3:808c7ef0
 [<80008784>] (gic_handle_irq) from [<80014044>] (__irq_svc+0x44/0x7c)

Link: http://lkml.kernel.org/r/1428953721-31349-1-git-send-email-rabin@rab.in
Link: http://lkml.kernel.org/r/1428957012-2319-1-git-send-email-rabin@rab.in

Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-04-16 09:32:17 -04:00
Linus Torvalds
eea3a00264 Merge branch 'akpm' (patches from Andrew)
Merge second patchbomb from Andrew Morton:

 - the rest of MM

 - various misc bits

 - add ability to run /sbin/reboot at reboot time

 - printk/vsprintf changes

 - fiddle with seq_printf() return value

* akpm: (114 commits)
  parisc: remove use of seq_printf return value
  lru_cache: remove use of seq_printf return value
  tracing: remove use of seq_printf return value
  cgroup: remove use of seq_printf return value
  proc: remove use of seq_printf return value
  s390: remove use of seq_printf return value
  cris fasttimer: remove use of seq_printf return value
  cris: remove use of seq_printf return value
  openrisc: remove use of seq_printf return value
  ARM: plat-pxa: remove use of seq_printf return value
  nios2: cpuinfo: remove use of seq_printf return value
  microblaze: mb: remove use of seq_printf return value
  ipc: remove use of seq_printf return value
  rtc: remove use of seq_printf return value
  power: wakeup: remove use of seq_printf return value
  x86: mtrr: if: remove use of seq_printf return value
  linux/bitmap.h: improve BITMAP_{LAST,FIRST}_WORD_MASK
  MAINTAINERS: CREDITS: remove Stefano Brivio from B43
  .mailmap: add Ricardo Ribalda
  CREDITS: add Ricardo Ribalda Delgado
  ...
2015-04-15 16:39:15 -07:00
Joe Perches
962e3707d9 tracing: remove use of seq_printf return value
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")

Miscellanea:

o Remove unused return value from trace_lookup_stack

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:25 -07:00
Joe Perches
94ff212d09 cgroup: remove use of seq_printf return value
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:25 -07:00
Joel Stanley
7a54f46b30 kernel/reboot.c: add orderly_reboot for graceful reboot
The kernel has orderly_poweroff which allows the kernel to initiate a
graceful shutdown of userspace, by running /sbin/poweroff.  This adds
orderly_reboot that will cause userspace to shut itself down by calling
/sbin/reboot.

This will be used for shutdown initiated by a system controller on
platforms that do not use ACPI.

orderly_reboot() should be used when the system wants to allow userspace
to gracefully shut itself down.  For cases where the system may imminently
catch on fire, the existing emergency_restart() provides an immediate
reboot without involving userspace.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:23 -07:00
Aaron Tomlin
972fae6993 kernel/hung_task.c: change hung_task.c to use for_each_process_thread()
In check_hung_uninterruptible_tasks() avoid the use of deprecated
while_each_thread().

The "max_count" logic will prevent a livelock - see commit 0c740d0a
("introduce for_each_thread() to replace the buggy while_each_thread()").
Having said this let's use for_each_process_thread().

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Wysochanski <dwysocha@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:22 -07:00
Jakub Sitnicki
96831c0a67 kernel/resource.c: remove deprecated __check_region() and friends
All users of __check_region(), check_region(), and check_mem_region() are
gone.  We got rid of the last user in v4.0-rc1.  Remove them.

bloat-o-meter on x86_64 shows:

add/remove: 0/3 grow/shrink: 0/0 up/down: 0/-102 (-102)
function                                     old     new   delta
__kstrtab___check_region                      15       -     -15
__ksymtab___check_region                      16       -     -16
__check_region                                71       -     -71

Signed-off-by: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:22 -07:00
Iulia Manda
2813893f8b kernel: conditionally support non-root users, groups and capabilities
There are a lot of embedded systems that run most or all of their
functionality in init, running as root:root.  For these systems,
supporting multiple users is not necessary.

This patch adds a new symbol, CONFIG_MULTIUSER, that makes support for
non-root users, non-root groups, and capabilities optional.  It is enabled
under CONFIG_EXPERT menu.

When this symbol is not defined, UID and GID are zero in any possible case
and processes always have all capabilities.

The following syscalls are compiled out: setuid, setregid, setgid,
setreuid, setresuid, getresuid, setresgid, getresgid, setgroups,
getgroups, setfsuid, setfsgid, capget, capset.

Also, groups.c is compiled out completely.

In kernel/capability.c, capable function was moved in order to avoid
adding two ifdef blocks.

This change saves about 25 KB on a defconfig build.  The most minimal
kernels have total text sizes in the high hundreds of kB rather than
low MB.  (The 25k goes down a bit with allnoconfig, but not that much.

The kernel was booted in Qemu.  All the common functionalities work.
Adding users/groups is not possible, failing with -ENOSYS.

Bloat-o-meter output:
add/remove: 7/87 grow/shrink: 19/397 up/down: 1675/-26325 (-24650)

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Iulia Manda <iulia.manda21@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:22 -07:00
Eric B Munson
5bbe3547aa mm: allow compaction of unevictable pages
Currently, pages which are marked as unevictable are protected from
compaction, but not from other types of migration.  The POSIX real time
extension explicitly states that mlock() will prevent a major page
fault, but the spirit of this is that mlock() should give a process the
ability to control sources of latency, including minor page faults.
However, the mlock manpage only explicitly says that a locked page will
not be written to swap and this can cause some confusion.  The
compaction code today does not give a developer who wants to avoid swap
but wants to have large contiguous areas available any method to achieve
this state.  This patch introduces a sysctl for controlling compaction
behavior with respect to the unevictable lru.  Users who demand no page
faults after a page is present can set compact_unevictable_allowed to 0
and users who need the large contiguous areas can enable compaction on
locked memory by leaving the default value of 1.

To illustrate this problem I wrote a quick test program that mmaps a
large number of 1MB files filled with random data.  These maps are
created locked and read only.  Then every other mmap is unmapped and I
attempt to allocate huge pages to the static huge page pool.  When the
compact_unevictable_allowed sysctl is 0, I cannot allocate hugepages
after fragmenting memory.  When the value is set to 1, allocations
succeed.

Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:17 -07:00
Vladimir Davydov
adbe427b92 memcg: zap mem_cgroup_lookup()
mem_cgroup_lookup() is a wrapper around mem_cgroup_from_id(), which
checks that id != 0 before issuing the function call.  Today, there is
no point in this additional check apart from optimization, because there
is no css with id <= 0, so that css_from_id, called by
mem_cgroup_from_id, will return NULL for any id <= 0.

Since mem_cgroup_from_id is only called from mem_cgroup_lookup, let us
zap mem_cgroup_lookup, substituting calls to it with mem_cgroup_from_id
and moving the check if id > 0 to css_from_id.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:16 -07:00
Linus Torvalds
fa2e5c073a Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc
Pull exec domain removal from Richard Weinberger:
 "This series removes execution domain support from Linux.

  The idea behind exec domains was to support different ABIs.  The
  feature was never complete nor stable.  Let's rip it out and make the
  kernel signal handling code less complicated"

* 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (27 commits)
  arm64: Removed unused variable
  sparc: Fix execution domain removal
  Remove rest of exec domains.
  arch: Remove exec_domain from remaining archs
  arc: Remove signal translation and exec_domain
  xtensa: Remove signal translation and exec_domain
  xtensa: Autogenerate offsets in struct thread_info
  x86: Remove signal translation and exec_domain
  unicore32: Remove signal translation and exec_domain
  um: Remove signal translation and exec_domain
  tile: Remove signal translation and exec_domain
  sparc: Remove signal translation and exec_domain
  sh: Remove signal translation and exec_domain
  s390: Remove signal translation and exec_domain
  mn10300: Remove signal translation and exec_domain
  microblaze: Remove signal translation and exec_domain
  m68k: Remove signal translation and exec_domain
  m32r: Remove signal translation and exec_domain
  m32r: Autogenerate offsets in struct thread_info
  frv: Remove signal translation and exec_domain
  ...
2015-04-15 13:53:55 -07:00