Commit graph

663629 commits

Author SHA1 Message Date
Paul E. McKenney 8ef0f37efb rcu: Open-code the rcu_cblist_empty() function
Because the rcu_cblist_empty() just samples the ->head pointer, and
because the rcu_cblist structure is quite straightforward, it makes
sense to open-code rcu_cblist_empty(p) as !p->head, cutting out a
level of indirection.  This commit makes this change.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-02 08:18:40 -07:00
Paul E. McKenney 98059b9861 rcu: Separately compile large rcu_segcblist functions
This commit creates a new kernel/rcu/rcu_segcblist.c file that
contains non-trivial segcblist functions.  Trivial functions
remain as static inline functions in kernel/rcu/rcu_segcblist.h

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2017-05-02 07:21:02 -07:00
Ingo Molnar 45753c5f31 srcu: Debloat the <linux/rcu_segcblist.h> header
Linus noticed that the <linux/rcu_segcblist.h> has huge inline functions
which should not be inline at all.

As a first step in cleaning this up, move them all to kernel/rcu/ and
only keep an absolute minimum of data type defines in the header:

  before:   -rw-r--r-- 1 mingo mingo 22284 May  2 10:25 include/linux/rcu_segcblist.h
   after:   -rw-r--r-- 1 mingo mingo  3180 May  2 10:22 include/linux/rcu_segcblist.h

More can be done, such as uninlining the large functions, which inlining
is unjustified even if it's an RCU internal matter.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-05-02 06:29:22 -07:00
Paul E. McKenney b5fe223a4b srcu: Adjust default auto-expediting holdoff
The default value for the kernel boot parameter srcutree.exp_holdoff
is 50 microseconds, which is too long for good Tree SRCU performance
(compared to Classic SRCU) on the workloads tested by Mike Galbraith.
This commit therefore sets the default value to 25 microseconds, which
shows excellent results in Mike's testing.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Mike Galbraith <efault@gmx.de>
2017-04-27 08:35:24 -07:00
Ingo Molnar 96fd20cf3f Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 "This series greatly reduces the performance degradation of Tree SRCU
  on a CPU-hotplug stress test.  The effect was not subtle:  Mike Galbraith
  measured Classic SRCU at 55 seconds and Tree SRCU at more than 16 -minutes-
  for this test.  Mike collected ftrace data that showed that Classic SRCU
  was auto-expediting invocations of synchronize_srcu() that found SRCU
  completely idle.  This series therefore adds this auto-expedite capability
  to Tree SRCU, bringing the performance shortfall to less than ten seconds,
  which is a great improvement over the initial shortfall of 15 minutes."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-27 07:41:37 +02:00
Paul E. McKenney 22607d66bb srcu: Specify auto-expedite holdoff time
On small systems, in the absence of readers, expedited SRCU grace
periods can complete in less than a microsecond.  This means that an
eight-CPU system can have all CPUs doing synchronize_srcu() in a tight
loop and almost always expedite.  This might actually be desirable in
some situations, but in general it is a good way to needlessly burn
CPU cycles.  And in those situations where it is desirable, your friend
is the function synchronize_srcu_expedited().

For other situations, this commit adds a kernel parameter that specifies
a holdoff between completing the last SRCU grace period and auto-expediting
the next.  If the next grace period starts before the holdoff expires,
auto-expediting is disabled.  The holdoff is 50 microseconds by default,
and can be tuned to the desired number of nanoseconds.  A value of zero
disables auto-expediting.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Mike Galbraith <efault@gmx.de>
2017-04-26 16:32:17 -07:00
Paul E. McKenney 2da4b2a7fd srcu: Expedite first synchronize_srcu() when idle
Classic SRCU in effect expedites the first synchronize_srcu() when SRCU
is idle, and Mike Galbraith demonstrated that some use cases do in fact
rely on this behavior.  In particular, Mike showed that Steven Rostedt's
hotplug stress script takes 55 seconds with Classic SRCU and more than
16 -minutes- when running Tree SRCU.  Assuming that each Tree SRCU's call
to synchronize_srcu() takes four milliseconds, this implies that Steven's
test invokes synchronize_srcu() in isolation, but more than once per
200 microseconds.  Mike used ftrace to demonstrate that the time between
successive calls to synchronize_srcu() ranged from 118 to 342 microseconds,
with one outlier at 80 milliseconds.  This data clearly indicates that
Tree SRCU needs to expedite the first invocation of synchronize_srcu()
during an SRCU idle period.

This commit therefor introduces a srcu_might_be_idle() function that
probabilistically checks whether or not SRCU is idle.  This function is
used by synchronize_rcu() as an additional criterion in deciding whether
or not to expedite.

(Hat trick to Peter Zijlstra for his earlier suggestion that this might
in fact be a problem.  Which for all I know might have motivated Mike to
look into it.)

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Mike Galbraith <efault@gmx.de>
2017-04-26 16:32:16 -07:00
Paul E. McKenney 1e9a038b7f srcu: Expedited grace periods with reduced memory contention
Commit f60d231a87 ("srcu: Crude control of expedited grace periods")
introduced a per-srcu_struct atomic counter to track outstanding
requests for grace periods.  This works, but represents a memory-contention
bottleneck.  This commit therefore uses the srcu_node combining tree
to remove this bottleneck.

This commit adds new ->srcu_gp_seq_needed_exp fields to the
srcu_data, srcu_node, and srcu_struct structures, which track the
farthest-in-the-future grace period that must be expedited, which in
turn requires that all nearer-term grace periods also be expedited.
Requests for expediting start with the srcu_data structure, run up
through the srcu_node tree, and end at the srcu_struct structure.
Note that it may be necessary to expedite a grace period that just
now started, and this is handled by a new srcu_funnel_exp_start()
function, which is invoked when the grace period itself is already
in its way, but when that grace period was not marked as expedited.

A new srcu_get_delay() function returns zero if there is at least one
expedited SRCU grace period in flight, or SRCU_INTERVAL otherwise.
This function is used to calculate delays:  Normal grace periods
are allowed to extend in order to cover more requests with a given
grace-period computation, which decreases per-request overhead.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Mike Galbraith <efault@gmx.de>
2017-04-26 16:32:16 -07:00
Paul E. McKenney 7f6733c3c6 srcu: Make rcutorture writer stalls print SRCU GP state
In the past, SRCU was simple enough that there was little point in
making the rcutorture writer stall messages print the SRCU grace-period
number state.  With the advent of Tree SRCU, this has changed.  This
commit therefore makes Classic, Tiny, and Tree SRCU report this state
to rcutorture as needed.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Mike Galbraith <efault@gmx.de>
2017-04-26 11:23:28 -07:00
Paul E. McKenney c7e88067c1 srcu: Exact tracking of srcu_data structures containing callbacks
The current Tree SRCU implementation schedules a workqueue for every
srcu_data covered by a given leaf srcu_node structure having callbacks,
even if only one of those srcu_data structures actually contains
callbacks.  This is clearly inefficient for workloads that don't feature
callbacks everywhere all the time.  This commit therefore adds an array
of masks that are used by the leaf srcu_node structures to track exactly
which srcu_data structures contain callbacks.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Mike Galbraith <efault@gmx.de>
2017-04-26 11:23:12 -07:00
Paul E. McKenney d160a727c4 srcu: Make SRCU be built by default
SRCU is optional, and included only if there is a "select SRCU" in effect.
However, we now have Tiny SRCU, so this commit defaults CONFIG_SRCU=y.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-04-24 08:36:02 -07:00
Paul E. McKenney 677df9d461 srcu: Fix Kconfig botch when SRCU not selected
If the CONFIG_SRCU option is not selected, for example, when building
arch/tile allnoconfig, the following build errors appear:

	kernel/rcu/tree.o: In function `srcu_online_cpu':
	tree.c:(.text+0x4248): multiple definition of `srcu_online_cpu'
	kernel/rcu/srcutree.o:srcutree.c:(.text+0x2120): first defined here
	kernel/rcu/tree.o: In function `srcu_offline_cpu':
	tree.c:(.text+0x4250): multiple definition of `srcu_offline_cpu'
	kernel/rcu/srcutree.o:srcutree.c:(.text+0x2160): first defined here

The corresponding .config file shows CONFIG_TREE_SRCU=y, but no sign
of CONFIG_SRCU, which fatally confuses SRCU's #ifdefs, resulting in
the above errors.  The reason this occurs is the folowing line in
init/Kconfig's definition for TREE_SRCU:

	default y if !TINY_RCU && !CLASSIC_SRCU

If CONFIG_CLASSIC_SRCU=n, as it will be in for allnoconfig, and if
CONFIG_SMP=y, then we will get CONFIG_TREE_SRCU=y but no CONFIG_SRCU,
as seen in the .config file, and which will result in the above errors.
This error did not show up during rcutorture testing because rcutorture
forces CONFIG_SRCU=y, as it must to prevent build errors in rcutorture.c.

This commit therefore conditions TREE_SRCU (and TINY_SRCU, while it is
at it) with SRCU, like this:

	default y if SRCU && !TINY_RCU && !CLASSIC_SRCU

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20170423162205.GP3956@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-24 08:14:48 +02:00
Ingo Molnar 58d30c36d4 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 - Documentation updates.

 - Miscellaneous fixes.

 - Parallelize SRCU callback handling (plus overlapping patches).

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-23 11:12:44 +02:00
Linus Torvalds 94836ecf1e Fix a 4.11 regression that triggers a BUG() on an attempt to use an
unsupported NFSv4 compound op.
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Merge tag 'nfsd-4.11-2' of git://linux-nfs.org/~bfields/linux

Pull nfsd bugfix from Bruce Fields:
 "Fix a 4.11 regression that triggers a BUG() on an attempt to use an
  unsupported NFSv4 compound op"

* tag 'nfsd-4.11-2' of git://linux-nfs.org/~bfields/linux:
  nfsd: fix oops on unsupported operation
2017-04-21 16:37:48 -07:00
Linus Torvalds 057a650bdc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Don't race in IPSEC dumps, from Yuejie Shi.

 2) Verify lengths properly in IPSEC reqeusts, from Herbert Xu.

 3) Fix out of bounds access in ipv6 segment routing code, from David
    Lebrun.

 4) Don't write into the header of cloned SKBs in smsc95xx driver, from
    James Hughes.

 5) Several other drivers have this bug too, fix them. From Eric
    Dumazet.

 6) Fix access to uninitialized data in TC action cookie code, from
    Wolfgang Bumiller.

 7) Fix double free in IPV6 segment routing, again from David Lebrun.

 8) Don't let userspace set the RTF_PCPU flag, oops. From David Ahern.

 9) Fix use after free in qrtr code, from Dan Carpenter.

10) Don't double-destroy devices in ip6mr code, from Nikolay
    Aleksandrov.

11) Don't pass out-of-range TX queue indices into drivers, from Tushar
    Dave.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (30 commits)
  netpoll: Check for skb->queue_mapping
  ip6mr: fix notification device destruction
  bpf, doc: update bpf maintainers entry
  net: qrtr: potential use after free in qrtr_sendmsg()
  bpf: Fix values type used in test_maps
  net: ipv6: RTF_PCPU should not be settable from userspace
  gso: Validate assumption of frag_list segementation
  kaweth: use skb_cow_head() to deal with cloned skbs
  ch9200: use skb_cow_head() to deal with cloned skbs
  lan78xx: use skb_cow_head() to deal with cloned skbs
  sr9700: use skb_cow_head() to deal with cloned skbs
  cx82310_eth: use skb_cow_head() to deal with cloned skbs
  smsc75xx: use skb_cow_head() to deal with cloned skbs
  ipv6: sr: fix double free of skb after handling invalid SRH
  MAINTAINERS: Add "B:" field for networking.
  net sched actions: allocate act cookie early
  qed: Fix issue in populating the PFC config paramters.
  qed: Fix possible system hang in the dcbnl-getdcbx() path.
  qed: Fix sending an invalid PFC error mask to MFW.
  qed: Fix possible error in populating max_tc field.
  ...
2017-04-21 13:20:47 -07:00
Tushar Dave c70b17b775 netpoll: Check for skb->queue_mapping
Reducing real_num_tx_queues needs to be in sync with skb queue_mapping
otherwise skbs with queue_mapping greater than real_num_tx_queues
can be sent to the underlying driver and can result in kernel panic.

One such event is running netconsole and enabling VF on the same
device. Or running netconsole and changing number of tx queues via
ethtool on same device.

e.g.
Unable to handle kernel NULL pointer dereference
tsk->{mm,active_mm}->context = 0000000000001525
tsk->{mm,active_mm}->pgd = fff800130ff9a000
              \|/ ____ \|/
              "@'/ .. \`@"
              /_| \__/ |_\
                 \__U_/
kworker/48:1(475): Oops [#1]
CPU: 48 PID: 475 Comm: kworker/48:1 Tainted: G           OE
4.11.0-rc3-davem-net+ #7
Workqueue: events queue_process
task: fff80013113299c0 task.stack: fff800131132c000
TSTATE: 0000004480e01600 TPC: 00000000103f9e3c TNPC: 00000000103f9e40 Y:
00000000    Tainted: G           OE
TPC: <ixgbe_xmit_frame_ring+0x7c/0x6c0 [ixgbe]>
g0: 0000000000000000 g1: 0000000000003fff g2: 0000000000000000 g3:
0000000000000001
g4: fff80013113299c0 g5: fff8001fa6808000 g6: fff800131132c000 g7:
00000000000000c0
o0: fff8001fa760c460 o1: fff8001311329a50 o2: fff8001fa7607504 o3:
0000000000000003
o4: fff8001f96e63a40 o5: fff8001311d77ec0 sp: fff800131132f0e1 ret_pc:
000000000049ed94
RPC: <set_next_entity+0x34/0xb80>
l0: 0000000000000000 l1: 0000000000000800 l2: 0000000000000000 l3:
0000000000000000
l4: 000b2aa30e34b10d l5: 0000000000000000 l6: 0000000000000000 l7:
fff8001fa7605028
i0: fff80013111a8a00 i1: fff80013155a0780 i2: 0000000000000000 i3:
0000000000000000
i4: 0000000000000000 i5: 0000000000100000 i6: fff800131132f1a1 i7:
00000000103fa4b0
I7: <ixgbe_xmit_frame+0x30/0xa0 [ixgbe]>
Call Trace:
 [00000000103fa4b0] ixgbe_xmit_frame+0x30/0xa0 [ixgbe]
 [0000000000998c74] netpoll_start_xmit+0xf4/0x200
 [0000000000998e10] queue_process+0x90/0x160
 [0000000000485fa8] process_one_work+0x188/0x480
 [0000000000486410] worker_thread+0x170/0x4c0
 [000000000048c6b8] kthread+0xd8/0x120
 [0000000000406064] ret_from_fork+0x1c/0x2c
 [0000000000000000]           (null)
Disabling lock debugging due to kernel taint
Caller[00000000103fa4b0]: ixgbe_xmit_frame+0x30/0xa0 [ixgbe]
Caller[0000000000998c74]: netpoll_start_xmit+0xf4/0x200
Caller[0000000000998e10]: queue_process+0x90/0x160
Caller[0000000000485fa8]: process_one_work+0x188/0x480
Caller[0000000000486410]: worker_thread+0x170/0x4c0
Caller[000000000048c6b8]: kthread+0xd8/0x120
Caller[0000000000406064]: ret_from_fork+0x1c/0x2c
Caller[0000000000000000]:           (null)

Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 15:45:19 -04:00
Nikolay Aleksandrov 723b929ca0 ip6mr: fix notification device destruction
Andrey Konovalov reported a BUG caused by the ip6mr code which is caused
because we call unregister_netdevice_many for a device that is already
being destroyed. In IPv4's ipmr that has been resolved by two commits
long time ago by introducing the "notify" parameter to the delete
function and avoiding the unregister when called from a notifier, so
let's do the same for ip6mr.

The trace from Andrey:
------------[ cut here ]------------
kernel BUG at net/core/dev.c:6813!
invalid opcode: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 1165 Comm: kworker/u4:3 Not tainted 4.11.0-rc7+ #251
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
01/01/2011
Workqueue: netns cleanup_net
task: ffff880069208000 task.stack: ffff8800692d8000
RIP: 0010:rollback_registered_many+0x348/0xeb0 net/core/dev.c:6813
RSP: 0018:ffff8800692de7f0 EFLAGS: 00010297
RAX: ffff880069208000 RBX: 0000000000000002 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88006af90569
RBP: ffff8800692de9f0 R08: ffff8800692dec60 R09: 0000000000000000
R10: 0000000000000006 R11: 0000000000000000 R12: ffff88006af90070
R13: ffff8800692debf0 R14: dffffc0000000000 R15: ffff88006af90000
FS:  0000000000000000(0000) GS:ffff88006cb00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe7e897d870 CR3: 00000000657e7000 CR4: 00000000000006e0
Call Trace:
 unregister_netdevice_many.part.105+0x87/0x440 net/core/dev.c:7881
 unregister_netdevice_many+0xc8/0x120 net/core/dev.c:7880
 ip6mr_device_event+0x362/0x3f0 net/ipv6/ip6mr.c:1346
 notifier_call_chain+0x145/0x2f0 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x51/0x90 net/core/dev.c:1647
 call_netdevice_notifiers net/core/dev.c:1663
 rollback_registered_many+0x919/0xeb0 net/core/dev.c:6841
 unregister_netdevice_many.part.105+0x87/0x440 net/core/dev.c:7881
 unregister_netdevice_many net/core/dev.c:7880
 default_device_exit_batch+0x4fa/0x640 net/core/dev.c:8333
 ops_exit_list.isra.4+0x100/0x150 net/core/net_namespace.c:144
 cleanup_net+0x5a8/0xb40 net/core/net_namespace.c:463
 process_one_work+0xc04/0x1c10 kernel/workqueue.c:2097
 worker_thread+0x223/0x19c0 kernel/workqueue.c:2231
 kthread+0x35e/0x430 kernel/kthread.c:231
 ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430
Code: 3c 32 00 0f 85 70 0b 00 00 48 b8 00 02 00 00 00 00 ad de 49 89
47 78 e9 93 fe ff ff 49 8d 57 70 49 8d 5f 78 eb 9e e8 88 7a 14 fe <0f>
0b 48 8b 9d 28 fe ff ff e8 7a 7a 14 fe 48 b8 00 00 00 00 00
RIP: rollback_registered_many+0x348/0xeb0 RSP: ffff8800692de7f0
---[ end trace e0b29c57e9b3292c ]---

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 15:35:47 -04:00
Daniel Borkmann cdb9049918 bpf, doc: update bpf maintainers entry
Add various related files that have been missing under
BPF entry covering essential parts of its infrastructure
and also add myself as co-maintainer.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 15:25:10 -04:00
Dan Carpenter 6f60f43810 net: qrtr: potential use after free in qrtr_sendmsg()
If skb_pad() fails then it frees the skb so we should check for errors.

Fixes: bdabad3e36 ("net: Add Qualcomm IPC router")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 15:19:27 -04:00
David Miller 89087c456f bpf: Fix values type used in test_maps
Maps of per-cpu type have their value element size adjusted to 8 if it
is specified smaller during various map operations.

This makes test_maps as a 32-bit binary fail, in fact the kernel
writes past the end of the value's array on the user's stack.

To be quite honest, I think the kernel should reject creation of a
per-cpu map that doesn't have a value size of at least 8 if that's
what the kernel is going to silently adjust to later.

If the user passed something smaller, it is a sizeof() calcualtion
based upon the type they will actually use (just like in this testcase
code) in later calls to the map operations.

Fixes: df570f5772 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_ARRAY")
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2017-04-21 15:16:46 -04:00
David Ahern 557c44be91 net: ipv6: RTF_PCPU should not be settable from userspace
Andrey reported a fault in the IPv6 route code:

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 1 PID: 4035 Comm: a.out Not tainted 4.11.0-rc7+ #250
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff880069809600 task.stack: ffff880062dc8000
RIP: 0010:ip6_rt_cache_alloc+0xa6/0x560 net/ipv6/route.c:975
RSP: 0018:ffff880062dced30 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff8800670561c0 RCX: 0000000000000006
RDX: 0000000000000003 RSI: ffff880062dcfb28 RDI: 0000000000000018
RBP: ffff880062dced68 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff880062dcfb28 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007feebe37e7c0(0000) GS:ffff88006cb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000205a0fe4 CR3: 000000006b5c9000 CR4: 00000000000006e0
Call Trace:
 ip6_pol_route+0x1512/0x1f20 net/ipv6/route.c:1128
 ip6_pol_route_output+0x4c/0x60 net/ipv6/route.c:1212
...

Andrey's syzkaller program passes rtmsg.rtmsg_flags with the RTF_PCPU bit
set. Flags passed to the kernel are blindly copied to the allocated
rt6_info by ip6_route_info_create making a newly inserted route appear
as though it is a per-cpu route. ip6_rt_cache_alloc sees the flag set
and expects rt->dst.from to be set - which it is not since it is not
really a per-cpu copy. The subsequent call to __ip6_dst_alloc then
generates the fault.

Fix by checking for the flag and failing with EINVAL.

Fixes: d52d3997f8 ("ipv6: Create percpu rt6_info")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:55:33 -04:00
Ilan Tayari 43170c4e0b gso: Validate assumption of frag_list segementation
Commit 07b26c9454 ("gso: Support partial splitting at the frag_list
pointer") assumes that all SKBs in a frag_list (except maybe the last
one) contain the same amount of GSO payload.

This assumption is not always correct, resulting in the following
warning message in the log:
    skb_segment: too many frags

For example, mlx5 driver in Striding RQ mode creates some RX SKBs with
one frag, and some with 2 frags.
After GRO, the frag_list SKBs end up having different amounts of payload.
If this frag_list SKB is then forwarded, the aforementioned assumption
is violated.

Validate the assumption, and fall back to software GSO if it not true.

Change-Id: Ia03983f4a47b6534dd987d7a2aad96d54d46d212
Fixes: 07b26c9454 ("gso: Support partial splitting at the frag_list pointer")
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:30:29 -04:00
David S. Miller 918b70244f Merge branch 'skb_cow_head'
Eric Dumazet says:

====================
net: use skb_cow_head() to deal with cloned skbs

James Hughes found an issue with smsc95xx driver. Same problematic code
is found in other drivers.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:07 -04:00
Eric Dumazet 39fba7835a kaweth: use skb_cow_head() to deal with cloned skbs
We can use skb_cow_head() to properly deal with clones,
especially the ones coming from TCP stack that allow their head being
modified. This avoids a copy.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:06 -04:00
Eric Dumazet 6bc6895bdd ch9200: use skb_cow_head() to deal with cloned skbs
We need to ensure there is enough headroom to push extra header,
but we also need to check if we are allowed to change headers.

skb_cow_head() is the proper helper to deal with this.

Fixes: 4a476bd6d1 ("usbnet: New driver for QinHeng CH9200 devices")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:06 -04:00
Eric Dumazet d4ca735919 lan78xx: use skb_cow_head() to deal with cloned skbs
We need to ensure there is enough headroom to push extra header,
but we also need to check if we are allowed to change headers.

skb_cow_head() is the proper helper to deal with this.

Fixes: 55d7de9de6 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Cc: Woojung Huh <woojung.huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:05 -04:00
Eric Dumazet d532c1082f sr9700: use skb_cow_head() to deal with cloned skbs
We need to ensure there is enough headroom to push extra header,
but we also need to check if we are allowed to change headers.

skb_cow_head() is the proper helper to deal with this.

Fixes: c9b37458e9 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:05 -04:00
Eric Dumazet a9e840a208 cx82310_eth: use skb_cow_head() to deal with cloned skbs
We need to ensure there is enough headroom to push extra header,
but we also need to check if we are allowed to change headers.

skb_cow_head() is the proper helper to deal with this.

Fixes: cc28a20e77 ("introduce cx82310_eth: Conexant CX82310-based ADSL router USB ethernet driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:05 -04:00
Eric Dumazet b7c6d26758 smsc75xx: use skb_cow_head() to deal with cloned skbs
We need to ensure there is enough headroom to push extra header,
but we also need to check if we are allowed to change headers.

skb_cow_head() is the proper helper to deal with this.

Fixes: d0cad87170 ("smsc75xx: SMSC LAN75xx USB gigabit ethernet adapter driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Hughes <james.hughes@raspberrypi.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:24:04 -04:00
David Lebrun 95b9b88d2d ipv6: sr: fix double free of skb after handling invalid SRH
The icmpv6_param_prob() function already does a kfree_skb(),
this patch removes the duplicate one.

Fixes: 1ababeba4a ("ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header)")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:16:01 -04:00
Linus Torvalds 92b4fc7563 powerpc fixes for 4.11 #8
Just two fixes. The first fixes kprobing a stdu, and is marked for stable as
 it's been broken for ~ever. In hindsight this could have gone in next.
 
 The other is a fix for a change we merged this cycle, where if we take a certain
 exception when the kernel is running relocated (currently only used for kdump),
 we checkstop the box.
 
 Thanks to:
   Ravi Bangoria.
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Merge tag 'powerpc-4.11-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Just two fixes.

  The first fixes kprobing a stdu, and is marked for stable as it's been
  broken for ~ever. In hindsight this could have gone in next.

  The other is a fix for a change we merged this cycle, where if we take
  a certain exception when the kernel is running relocated (currently
  only used for kdump), we checkstop the box.

  Thanks to Ravi Bangoria"

* tag 'powerpc-4.11-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64: Fix HMI exception on LE with CONFIG_RELOCATABLE=y
  powerpc/kprobe: Fix oops when kprobed on 'stdu' instruction
2017-04-21 09:34:45 -07:00
Linus Torvalds fe7ba28933 pci-v4.11-fixes-5
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Merge tag 'pci-v4.11-fixes-5' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI fix from Bjorn Helgaas:
 "Sorry this is so late. It's been in -next for over a week, but I
  forgot to send it on until now.

  A single fix to the DT binding of the HiSilicon PCIe host support"

* tag 'pci-v4.11-fixes-5' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: hisi: Fix DT binding (hisi-pcie-almost-ecam)
2017-04-21 09:26:34 -07:00
Linus Torvalds a9aa1908e2 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block layer fixes from Jens Axboe:
 "A couple of last minute fixes for regressions in this cycle. More
  specifically:

   - Two patches from Andy, adjusting the NVMe APST quirks to avoid some
     issues specific to one Toshiba drive, and some variant of Samsung
     on two specific Dell laptops.

   - A fix for mtip32xx, turning off mq scheduling on that device. We
     have a real fix for this, but it's too late in the cycle.
     Thankfully we already have a NO_SCHED flag we can apply here. A
     prep patch for this is ensuring that we honor the NO_SCHED flag
     when attempting to online switch schedulers, previsouly we only did
     so for drive load time. From Ming.

   - Fixing an oops in blk-mq polling with scheduling attached. This one
     is easily reproducible, it would be a shame to release 4.11 with
     that issue. From me.

  I'd prefer not having to send in patches at this point in time, but
  the above are all things that have regressed in this cycle and the
  fixes are relatively straight forward"

* 'for-linus' of git://git.kernel.dk/linux-block:
  blk-mq: fix potential oops with polling and blk-mq scheduler
  nvme: Quirk APST off on "THNSF5256GPUK TOSHIBA"
  nvme: Adjust the Samsung APST quirk
  mtip32xx: pass BLK_MQ_F_NO_SCHED
  block: respect BLK_MQ_F_NO_SCHED
2017-04-21 09:20:35 -07:00
Linus Torvalds 4664e3221b ACPI fix for final v4.11
- Avoid a false-positive warning regarding a variable that may not
    be initialized that started to trigger after a previous general
    build fix (Arnd Bergmann).
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Merge tag 'acpi-4.11-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI build fix from Rafael Wysocki:
 "This avoids a false-positive build warning from the compiler.

  Specifics:

   - Avoid a false-positive warning regarding a variable that may not be
     initialized that started to trigger after a previous general build
     fix (Arnd Bergmann)"

* tag 'acpi-4.11-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / power: Avoid maybe-uninitialized warning
2017-04-21 09:18:17 -07:00
Linus Torvalds 11b211ede8 MMC core:
- kmalloc sdio scratch buffer to make it DMA-friendly
 
 MMC host:
  - dw_mmc: Fix behaviour for SDIO IRQs when runtime PM is used
  - sdhci-esdhc-imx: Correct pad I/O drive strength for UHS-DDR50 cards
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Merge tag 'mmc-v4.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc

Pull MMC fixes from Ulf Hansson:
 "MMC core:

   - kmalloc sdio scratch buffer to make it DMA-friendly

  MMC host:

   - dw_mmc: Fix behaviour for SDIO IRQs when runtime PM is used

   - sdhci-esdhc-imx: Correct pad I/O drive strength for UHS-DDR50
     cards"

* tag 'mmc-v4.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-esdhc-imx: increase the pad I/O drive strength for DDR50 card
  mmc: dw_mmc: Don't allow Runtime PM for SDIO cards
  mmc: sdio: fix alignment issue in struct sdio_func
2017-04-21 09:15:43 -07:00
Linus Torvalds 4d4dfc1caa Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input fixlet from Dmitry Torokhov:
 "An update to Elan PS/2 driver to allow working on yet another
  Lifebook"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: elantech - add Fujitsu Lifebook E547 to force crc_enabled
2017-04-21 09:13:43 -07:00
David S. Miller b0522e13b2 MAINTAINERS: Add "B:" field for networking.
We want people to report bugs to the netdev list.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 10:44:47 -04:00
Paul E. McKenney f2094107ac Merge branches 'doc.2017.04.12a', 'fixes.2017.04.19a' and 'srcu.2017.04.21a' into HEAD
doc.2017.04.12a: Documentation updates
fixes.2017.04.19a: Miscellaneous fixes
srcu.2017.04.21a: Parallelize SRCU callback handling
2017-04-21 06:00:13 -07:00
Paul E. McKenney bcbfdd01dc rcu: Make non-preemptive schedule be Tasks RCU quiescent state
Currently, a call to schedule() acts as a Tasks RCU quiescent state
only if a context switch actually takes place.  However, just the
call to schedule() guarantees that the calling task has moved off of
whatever tracing trampoline that it might have been one previously.
This commit therefore plumbs schedule()'s "preempt" parameter into
rcu_note_context_switch(), which then records the Tasks RCU quiescent
state, but only if this call to schedule() was -not- due to a preemption.

To avoid adding overhead to the common-case context-switch path,
this commit hides the rcu_note_context_switch() check under an existing
non-common-case check.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-04-21 05:59:27 -07:00
Paul E. McKenney 0497b489b8 srcu: Expedite srcu_schedule_cbs_snp() callback invocation
Although Tree SRCU does reduce delays when there is at least one
synchronize_srcu_expedited() invocation pending, srcu_schedule_cbs_snp()
still waits for SRCU_INTERVAL before invoking callbacks.  Since
synchronize_srcu_expedited() now posts a callback and waits for
that callback to do a wakeup, this destroys the expedited nature of
synchronize_srcu_expedited().  This destruction became apparent to
Marc Zyngier in the guise of a guest-OS bootup slowdown from five
seconds to no fewer than forty seconds.

This commit therefore invokes callbacks immediately at the end of the
grace period when there is at least one synchronize_srcu_expedited()
invocation pending.  This brought Marc's guest-OS bootup times back
into the realm of reason.

Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-21 05:59:27 -07:00
Paul E. McKenney da915ad5cf srcu: Parallelize callback handling
Peter Zijlstra proposed using SRCU to reduce mmap_sem contention [1,2],
however, there are workloads that could result in a high volume of
concurrent invocations of call_srcu(), which with current SRCU would
result in excessive lock contention on the srcu_struct structure's
->queue_lock, which protects SRCU's callback lists.  This commit therefore
moves SRCU to per-CPU callback lists, thus greatly reducing contention.

Because a given SRCU instance no longer has a single centralized callback
list, starting grace periods and invoking callbacks are both more complex
than in the single-list Classic SRCU implementation.  Starting grace
periods and handling callbacks are now handled using an srcu_node tree
that is in some ways similar to the rcu_node trees used by RCU-bh,
RCU-preempt, and RCU-sched (for example, the srcu_node tree shape is
controlled by exactly the same Kconfig options and boot parameters that
control the shape of the rcu_node tree).

In addition, the old per-CPU srcu_array structure is now named srcu_data
and contains an rcu_segcblist structure named ->srcu_cblist for its
callbacks (and a spinlock to protect this).  The srcu_struct gets
an srcu_gp_seq that is used to associate callback segments with the
corresponding completion-time grace-period number.  These completion-time
grace-period numbers are propagated up the srcu_node tree so that the
grace-period workqueue handler can determine whether additional grace
periods are needed on the one hand and where to look for callbacks that
are ready to be invoked.

The srcu_barrier() function must now wait on all instances of the per-CPU
->srcu_cblist.  Because each ->srcu_cblist is protected by ->lock,
srcu_barrier() can remotely add the needed callbacks.  In theory,
it could also remotely start grace periods, but in practice doing so
is complex and racy.  And interestingly enough, it is never necessary
for srcu_barrier() to start a grace period because srcu_barrier() only
enqueues a callback when a callback is already present--and it turns out
that a grace period has to have already been started for this pre-existing
callback.  Furthermore, it is only the callback that srcu_barrier()
needs to wait on, not any particular grace period.  Therefore, a new
rcu_segcblist_entrain() function enqueues the srcu_barrier() function's
callback into the same segment occupied by the last pre-existing callback
in the list.  The special case where all the pre-existing callbacks are
on a different list (because they are in the process of being invoked)
is handled by enqueuing srcu_barrier()'s callback into the RCU_DONE_TAIL
segment, relying on the done-callbacks check that takes place after all
callbacks are inovked.

Note that the readers use the same algorithm as before.  Note that there
is a separate srcu_idx that tells the readers what counter to increment.
This unfortunately cannot be combined with srcu_gp_seq because they
need to be incremented at different times.

This commit introduces some ugly #ifdefs in rcutorture.  These will go
away when I feel good enough about Tree SRCU to ditch Classic SRCU.

Some crude performance comparisons, courtesy of a quickly hacked rcuperf
asynchronous-grace-period capability:

			Callback Queuing Overhead
			-------------------------
	# CPUS		Classic SRCU	Tree SRCU
	------          ------------    ---------
	     2              0.349 us     0.342 us
	    16             31.66  us     0.4   us
	    41             ---------     0.417 us

The times are the 90th percentiles, a statistic that was chosen to reject
the overheads of the occasional srcu_barrier() call needed to avoid OOMing
the test machine.  The rcuperf test hangs when running Classic SRCU at 41
CPUs, hence the line of dashes.  Despite the hacks to both the rcuperf code
and that statistics, this is a convincing demonstration of Tree SRCU's
performance and scalability advantages.

[1] https://lwn.net/Articles/309030/
[2] https://patchwork.kernel.org/patch/5108281/

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Fix initialization if synchronize_srcu_expedited() called first. ]
2017-04-21 05:59:26 -07:00
Paul E. McKenney 6ade8694f4 kvm: Move srcu_struct fields to end of struct kvm
Parallelizing SRCU callback handling will increase the size of
srcu_struct, which will move the kvm structure's kvm_arch field out
of reach of powerpc's current assembly code, which will result in the
following sort of build error:

arch/powerpc/kvm/book3s_hv_rmhandlers.S:617: Error: operand out of range (0x000000000000b328 is not between 0xffffffffffff8000 and 0x0000000000007fff)

This commit moves the srcu_struct fields in the kvm structure to follow
the kvm_arch field, which will allow powerpc's assembly code to continue
to be able to reach the kvm_arch field.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Michael Ellerman <michaele@au1.ibm.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
[ paulmck: Moved this commit to precede SRCU callback parallelization,
  and reworded the commit log into future tense, all in the name of
  bisectability. ]
2017-04-21 05:56:31 -07:00
Linus Torvalds c154165e93 Merge branch 'akpm' (patches from Andrew)
Merge two mm fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: prevent NR_ISOLATE_* stats from going negative
  Revert "mm, page_alloc: only use per-cpu allocator for irq-safe requests"
2017-04-20 15:31:08 -07:00
Rabin Vincent fc280fe871 mm: prevent NR_ISOLATE_* stats from going negative
Commit 6afcf8ef0c ("mm, compaction: fix NR_ISOLATED_* stats for pfn
based migration") moved the dec_node_page_state() call (along with the
page_is_file_cache() call) to after putback_lru_page().

But page_is_file_cache() can change after putback_lru_page() is called,
so it should be called before putback_lru_page(), as it was before that
patch, to prevent NR_ISOLATE_* stats from going negative.

Without this fix, non-CONFIG_SMP kernels end up hanging in the
while(too_many_isolated()) { congestion_wait() } loop in
shrink_active_list() due to the negative stats.

 Mem-Info:
  active_anon:32567 inactive_anon:121 isolated_anon:1
  active_file:6066 inactive_file:6639 isolated_file:4294967295
                                                    ^^^^^^^^^^
  unevictable:0 dirty:115 writeback:0 unstable:0
  slab_reclaimable:2086 slab_unreclaimable:3167
  mapped:3398 shmem:18366 pagetables:1145 bounce:0
  free:1798 free_pcp:13 free_cma:0

Fixes: 6afcf8ef0c ("mm, compaction: fix NR_ISOLATED_* stats for pfn based migration")
Link: http://lkml.kernel.org/r/1492683865-27549-1-git-send-email-rabin.vincent@axis.com
Signed-off-by: Rabin Vincent <rabinv@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ming Ling <ming.ling@spreadtrum.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-20 15:30:18 -07:00
Mel Gorman d34b0733b4 Revert "mm, page_alloc: only use per-cpu allocator for irq-safe requests"
This reverts commit 374ad05ab6.

While the patch worked great for userspace allocations, the fact that
softirq loses the per-cpu allocator caused problems.  It needs to be
redone taking into account that a separate list is needed for hard/soft
IRQs or alternatively find a cheap way of detecting reentry due to an
interrupt.  Both are possible but sufficiently tricky that it shouldn't
be rushed.

Jesper had one method for allowing softirqs but reported that the cost
was high enough that it performed similarly to a plain revert.  His
figures for netperf TCP_STREAM were as follows

  Baseline v4.10.0  : 60316 Mbit/s
  Current 4.11.0-rc6: 47491 Mbit/s
  Jesper's patch    : 60662 Mbit/s
  This patch        : 60106 Mbit/s

As this is a regression, I wish to revert to noirq allocator for now and
go back to the drawing board.

Link: http://lkml.kernel.org/r/20170415145350.ixy7vtrzdzve57mh@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Tariq Toukan <ttoukan.linux@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-20 15:30:18 -07:00
Jens Axboe 3a07bb1d76 blk-mq: fix potential oops with polling and blk-mq scheduler
If we have a scheduler attached, blk_mq_tag_to_rq() on the
scheduled tags will return NULL if a request is no longer
in flight. This is different than using the normal tags,
where it will always return the fixed request. Check for
this condition for polling, in case we happen to enter
polling for a completed request.

The request address remains valid, so this check and return
should be perfectly safe.

Fixes: bd166ef183 ("blk-mq-sched: add framework for MQ capable IO schedulers")
Tested-by: Stephen Bates <sbates@raithlin.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 14:53:28 -06:00
Andy Lutomirski be56945c4e nvme: Quirk APST off on "THNSF5256GPUK TOSHIBA"
There's a report that it malfunctions with APST on.

See https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1678184

Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 14:42:10 -06:00
Andy Lutomirski ff5350a86b nvme: Adjust the Samsung APST quirk
I got a couple more reports: the Samsung APST issues appears to
affect multiple 950-series devices in Dell XPS 15 9550 and Precision
5510 laptops.  Change the quirk: rather than blacklisting the
firmware on the first problematic SSD that was reported, disable
APST on all 144d:a802 devices if they're installed in the two
affected Dell models.  While we're at it, disable only the deepest
sleep state instead of all of them -- the reporters say that this is
sufficient to fix the problem.

(I have a device that appears to be entirely identical to one of the
affected devices, but I have a different Dell laptop, so it's not
the case that all Samsung devices with firmware BXW75D0Q are broken
under all circumstances.)

Samsung engineers have an affected system, and hopefully they'll
give us a better workaround some time soon.  In the mean time, this
should minimize regressions.

See https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1678184

Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 14:42:09 -06:00
Wolfgang Bumiller e0535ce58b net sched actions: allocate act cookie early
Policing filters do not use the TCA_ACT_* enum and the tb[]
nlattr array in tcf_action_init_1() doesn't get filled for
them so we should not try to look for a TCA_ACT_COOKIE
attribute in the then uninitialized array.
The error handling in cookie allocation then calls
tcf_hash_release() leading to invalid memory access later
on.
Additionally, if cookie allocation fails after an already
existing non-policing filter has successfully been changed,
tcf_action_release() should not be called, also we would
have to roll back the changes in the error handling, so
instead we now allocate the cookie early and assign it on
success at the end.

CVE-2017-7979
Fixes: 1045ba77a5 ("net sched actions: Add support for user cookies")
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-20 16:32:07 -04:00
David S. Miller 43af390573 Merge branch 'qed-dcbx-fixes'
Sudarsana Reddy Kalluru says:

====================
qed: Dcbx bug fixes

The series has set of bug fixes for dcbx implementation of qed driver.
Please consider applying this to 'net' branch.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-20 16:29:41 -04:00