Commit Graph

440794 Commits

Author SHA1 Message Date
Linus Torvalds
edf2377c47 - Call put_device() instead of kfree() - core
- Add DT support - gpio-backlight
  - Use managed resources - lm3639_bl
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Merge tag 'backlight-for-linus-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight changes from Lee Jones:
 - core: call put_device() instead of kfree()
 - gpio-backlight: add DT support
 - lm3639_bl driver: use managed resources

* tag 'backlight-for-linus-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: lm3639: Use devm_backlight_device_register()
  backlight: gpio-backlight: Add DT support
  backlight: core: Replace kfree with put_device
2014-04-10 08:52:35 -07:00
John W. Linville
029d3ac972 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem 2014-04-10 09:58:06 -04:00
Jens Axboe
360f92c244 block: fix regression with block enabled tagging
Martin reported that his test system would not boot with
current git, it oopsed with this:

BUG: unable to handle kernel paging request at ffff88046c6c9e80
IP: [<ffffffff812971e0>] blk_queue_start_tag+0x90/0x150
PGD 1ddf067 PUD 1de2067 PMD 47fc7d067 PTE 800000046c6c9060
Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: sd_mod lpfc(+) scsi_transport_fc scsi_tgt oracleasm
rpcsec_gss_krb5 ipv6 igb dca i2c_algo_bit i2c_core hwmon
CPU: 3 PID: 87 Comm: kworker/u17:1 Not tainted 3.14.0+ #246
Hardware name: Supermicro X9DRX+-F/X9DRX+-F, BIOS 3.00 07/09/2013
Workqueue: events_unbound async_run_entry_fn
task: ffff8802743c2150 ti: ffff880273d02000 task.ti: ffff880273d02000
RIP: 0010:[<ffffffff812971e0>]  [<ffffffff812971e0>]
blk_queue_start_tag+0x90/0x150
RSP: 0018:ffff880273d03a58  EFLAGS: 00010092
RAX: ffff88046c6c9e78 RBX: ffff880077208e78 RCX: 00000000fffc8da6
RDX: 00000000fffc186d RSI: 0000000000000009 RDI: 00000000fffc8d9d
RBP: ffff880273d03a88 R08: 0000000000000001 R09: ffff8800021c2410
R10: 0000000000000005 R11: 0000000000015b30 R12: ffff88046c5bb8a0
R13: ffff88046c5c0890 R14: 000000000000001e R15: 000000000000001e
FS:  0000000000000000(0000) GS:ffff880277b00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88046c6c9e80 CR3: 00000000018f6000 CR4: 00000000000407e0
Stack:
 ffff880273d03a98 ffff880474b18800 0000000000000000 ffff880474157000
 ffff88046c5c0890 ffff880077208e78 ffff880273d03ae8 ffffffff813b9e62
 ffff880200000010 ffff880474b18968 ffff880474b18848 ffff88046c5c0cd8
Call Trace:
 [<ffffffff813b9e62>] scsi_request_fn+0xf2/0x510
 [<ffffffff81293167>] __blk_run_queue+0x37/0x50
 [<ffffffff8129ac43>] blk_execute_rq_nowait+0xb3/0x130
 [<ffffffff8129ad24>] blk_execute_rq+0x64/0xf0
 [<ffffffff8108d2b0>] ? bit_waitqueue+0xd0/0xd0
 [<ffffffff813bba35>] scsi_execute+0xe5/0x180
 [<ffffffff813bbe4a>] scsi_execute_req_flags+0x9a/0x110
 [<ffffffffa01b1304>] sd_spinup_disk+0x94/0x460 [sd_mod]
 [<ffffffff81160000>] ? __unmap_hugepage_range+0x200/0x2f0
 [<ffffffffa01b2b9a>] sd_revalidate_disk+0xaa/0x3f0 [sd_mod]
 [<ffffffffa01b2fb8>] sd_probe_async+0xd8/0x200 [sd_mod]
 [<ffffffff8107703f>] async_run_entry_fn+0x3f/0x140
 [<ffffffff8106a1c5>] process_one_work+0x175/0x410
 [<ffffffff8106b373>] worker_thread+0x123/0x400
 [<ffffffff8106b250>] ? manage_workers+0x160/0x160
 [<ffffffff8107104e>] kthread+0xce/0xf0
 [<ffffffff81070f80>] ? kthread_freezable_should_stop+0x70/0x70
 [<ffffffff815f0bac>] ret_from_fork+0x7c/0xb0
 [<ffffffff81070f80>] ? kthread_freezable_should_stop+0x70/0x70
Code: 48 0f ab 11 72 db 48 81 4b 40 00 00 10 00 89 83 08 01 00 00 48 89
df 49 8b 04 24 48 89 1c d0 e8 f7 a8 ff ff 49 8b 85 28 05 00 00 <48> 89
58 08 48 89 03 49 8d 85 28 05 00 00 48 89 43 08 49 89 9d
RIP  [<ffffffff812971e0>] blk_queue_start_tag+0x90/0x150
 RSP <ffff880273d03a58>
CR2: ffff88046c6c9e80

Martin bisected and found this to be the problem patch;

	commit 6d113398dc
	Author: Jan Kara <jack@suse.cz>
	Date:   Mon Feb 24 16:39:54 2014 +0100

	    block: Stop abusing rq->csd.list in blk-softirq

and the problem was immediately apparent. The patch states that
it is safe to reuse queuelist at completion time, since it is
no longer used. However, that is not true if a device is using
block enabled tagging. If that is the case, then the queuelist
is reused to keep track of busy tags. If a device also ended
up using softirq completions, we'd reuse ->queuelist for the
IPI handling while block tagging was still using it. Boom.

Fix this by adding a new ipi_list list head, and share the
memory used with the request hash table. The hash table is
never used after the request is moved to the dispatch list,
which happens long before any potential completion of the
request. Add a new request bit for this, so we don't have
cases that check rq->hash while it could potentially have
been reused for the IPI completion.

Reported-by: Martin K. Petersen <martin.petersen@oracle.com>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-09 21:54:06 -06:00
Martin K. Petersen
2bfad21ecc scsi: Make sure cmd_flags are 64-bit
cmd_flags in struct request is now 64 bits wide but the scsi_execute
functions truncated arguments passed to int leading to errors. Make sure
the flags parameters are u64.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Jens Axboe <axboe@fb.com>
CC: Jan Kara <jack@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-09 20:26:20 -06:00
Mathieu Desnoyers
abb43f6998 tracing: Fix anonymous unions in struct ftrace_event_call
gcc <= 4.5.x has significant limitations with respect to initialization
of anonymous unions within structures. They need to be surrounded by
brackets, _and_ they need to be initialized in the same order in which
they appear in the structure declaration.

Link: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10676
Link: http://lkml.kernel.org/r/1397077568-3156-1-git-send-email-mathieu.desnoyers@efficios.com

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-04-09 20:02:55 -04:00
Behan Webster
c4586256f0 x86: LLVMLinux: Fix "incomplete type const struct x86cpu_device_id"
Similar to the fix in 40413dcb7b

MODULE_DEVICE_TABLE(x86cpu, ...) expects the struct to be called struct
x86cpu_device_id, and not struct x86_cpu_id which is what is used in the rest
of the kernel code.  Although gcc seems to ignore this error, clang fails
without this define to fix the name.

Code from drivers/thermal/x86_pkg_temp_thermal.c
static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = { ... };
MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);

Error from clang:
drivers/thermal/x86_pkg_temp_thermal.c:577:1: error: variable has
      incomplete type 'const struct x86cpu_device_id'
MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
^
include/linux/module.h:145:3: note: expanded from macro
      'MODULE_DEVICE_TABLE'
  MODULE_GENERIC_TABLE(type##_device, name)
  ^
include/linux/module.h:87:32: note: expanded from macro
      'MODULE_GENERIC_TABLE'
extern const struct gtype##_id __mod_##gtype##_table            \
                               ^
<scratch space>:143:1: note: expanded from here
__mod_x86cpu_device_table
^
drivers/thermal/x86_pkg_temp_thermal.c:577:1: note: forward declaration of
      'struct x86cpu_device_id'
include/linux/module.h:145:3: note: expanded from macro
      'MODULE_DEVICE_TABLE'
  MODULE_GENERIC_TABLE(type##_device, name)
  ^
include/linux/module.h:87:21: note: expanded from macro
      'MODULE_GENERIC_TABLE'
extern const struct gtype##_id __mod_##gtype##_table            \
                    ^
<scratch space>:141:1: note: expanded from here
x86cpu_device_id
^
1 error generated.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-09 13:44:35 -07:00
Jan-Simon Möller
fd2d0a19ab x86 kbuild: LLVMLinux: More cc-options added for clang
Protect more options for x86 with cc-option so that we don't get errors when
using clang instead of gcc.  Add more or different options when using clang as
well. Also need to enforce that SSE is off for clang and the stack is 8-byte
aligned.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
2014-04-09 13:44:35 -07:00
Behan Webster
3ddf5ce966 x86, acpi: LLVMLinux: Remove nested functions from Thinkpad ACPI
The only real change is passing in event_mask to the formerly nested functions.
Otherwise it's just moving around function and macro code.

This is the only place in the Linux kernel where nested functions are still in
use. Nested functions aren't part of the C standards, and complicate the
generated code. Although the Linux Kernel has never set out to be entirely C
standard compliant, it is increasingly compliant to the standard which is
supported by other compilers such as Clang. The LLVMLinux project is working on
being able to compile the Linux kernel with Clang. The use of nested functions
blocks this effort.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
2014-04-09 13:44:35 -07:00
Mark Charlebois
565cbdc2fe LLVMLinux: Add support for clang to compiler.h and new compiler-clang.h
Add a compiler-clang.h file to add specific macros needed for compiling the
kernel with clang.

Initially the only override required is the macro for silencing the
compiler for a purposefully uninintialized variable.

Author: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
2014-04-09 13:44:35 -07:00
Behan Webster
aa93685afb LLVMLinux: Remove warning about returning an uninitialized variable
Fix uninitialized return code in default case in cmpxchg-local.h

This patch fixes the code to prevent an uninitialized return value that is detected
when compiling with clang. The bug produces numerous warnings when compiling the
Linux kernel with clang.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2014-04-09 13:44:35 -07:00
Jan-Simon Möller
db46293bc6 kbuild: LLVMLinux: Fix LINUX_COMPILER definition script for compilation with clang
When building the LINUX_COMPILER definition, instead of merely taking the last
line from "$(CC) -v", grep for ' version ' in the output. This supports both
gcc and clang.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
2014-04-09 13:44:35 -07:00
Jan-Simon Möller
8a260796a1 Documentation: LLVMLinux: Update Documentation/dontdiff
Clang has a few other kinds of derived files which shouldn't be added to a
patch. Add them to the Documentation/dontdiff file to prevent this.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Cc: PaX Team <pageexec@freemail.hu>
2014-04-09 13:44:34 -07:00
Jan-Simon Möller
3d3d6b8474 kbuild: LLVMLinux: Adapt warnings for compilation with clang
When compiling kernel with clang, disable warnings which are too noisy, and
add the clang flag catch-undefined-behavior.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <mcharleb@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
2014-04-09 13:44:34 -07:00
Behan Webster
61163efae0 kbuild: LLVMLinux: Add Kbuild support for building kernel with Clang
Add support to toplevel Makefile for compiling with clang, both for
HOSTCC and CC. Use cc-option to prevent gcc option from breaking clang, and
from clang options from breaking gcc.

Clang 3.4 semantics are the same as gcc semantics for unsupported flags. For
unsupported warnings clang 3.4 returns true but shows a warning and gcc shows
a warning and returns false.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
2014-04-09 13:44:34 -07:00
Dmitry Petukhov
f34c4a35d8 l2tp: take PMTU from tunnel UDP socket
When l2tp driver tries to get PMTU for the tunnel destination, it uses
the pointer to struct sock that represents PPPoX socket, while it
should use the pointer that represents UDP socket of the tunnel.

Signed-off-by: Dmitry Petukhov <dmgenp@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-09 15:24:38 -04:00
Tim Gardner
a5065eb6da ALSA: usb-audio: Suppress repetitive debug messages from retire_playback_urb()
BugLink: http://bugs.launchpad.net/bugs/1305133

Malfunctioning or slow devices can cause a flood of dmesg SPAM.

I've ignored checkpatch.pl complaints about the use of printk_ratelimit() in favour
of prior art in sound/usb/pcm.c.

WARNING: Prefer printk_ratelimited or pr_<level>_ratelimited to printk_ratelimit
+	if (printk_ratelimit() &&

Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Eldad Zack <eldad@fogrefinery.com>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-04-09 21:07:38 +02:00
Mugunthan V N
629c9a8fd0 drivers: net: cpsw: Add default vlan for dual emac case also
Dual EMAC works with VLAN segregation of the ports, so default vlan needs
to be added in dual EMAC case else default vlan will be tagged for all
egress packets and vlan unaware switches/servers will drop packets
from the EVM.

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Tested-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-09 14:55:37 -04:00
Felix Fietkau
5869e795e0 ath9k: fix a scheduling while atomic bug in CSA handling
Commit "ath9k: prepare for multi-interface CSA support" added a call to
ieee80211_iterate_active_interfaces in atomic context (beacon tasklet),
which is crashing.
Use ieee80211_iterate_active_interfaces_atomic instead.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:55 -04:00
Felix Fietkau
09efc56345 ath9k_hw: reduce ANI firstep range for older chips
Use 0-8 instead of 0-16, which is closer to the old implementation.
Also drop the overwrite of the firstep_low parameter to improve
stability.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:55 -04:00
Janusz Dziedzic
4d76248013 ath9k: Enable DFS only when ATH9K_DFS_CERTIFIED
Add DFS interface combination only when
CONFIG_ATH9K_DFS_CERTIFIED is set. In other case
user can run CAC/beaconing without proper handling
of pulse events (without radar detection activated).

Reported-by: Cedric Voncken <cedric.voncken@acksys.fr>
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:55 -04:00
Rafał Miłecki
12cd43c6ed b43: Fix machine check error due to improper access of B43_MMIO_PSM_PHY_HDR
Register B43_MMIO_PSM_PHY_HDR is 16 bit one, so accessing it with 32b
functions isn't safe. On my machine it causes delayed (!) CPU exception:

Disabling lock debugging due to kernel taint
mce: [Hardware Error]: CPU 0: Machine Check Exception: 4 Bank 4: b200000000070f0f
mce: [Hardware Error]: TSC 164083803dc
mce: [Hardware Error]: PROCESSOR 2:20fc2 TIME 1396650505 SOCKET 0 APIC 0 microcode 0
mce: [Hardware Error]: Run the above through 'mcelog --ascii'
mce: [Hardware Error]: Machine check: Processor context corrupt
Kernel panic - not syncing: Fatal machine check on current CPU
Kernel Offset: 0x0 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffff9fffffff)

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org> [2.6.35+]
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:55 -04:00
Paul Bolle
5212f518ac rtlwifi: btcoexist: remove undefined Kconfig macros
There are references to four undefined Kconfig macros in the code.
Commit 8542373dcc ("Staging: rtl8812ae: remove undefined Kconfig
macros") removed identical references from that staging driver, but
they resurfaced in rtlwifi. Remove these again as the checks for them
still will always evaluate to false.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:54 -04:00
Chun-Yeow Yeoh
cdacdcc246 ath9k_htc: set IEEE80211_TX_STAT_AMPDU for acked aggregated frames
Frame aggregation requires the IEEE80211_TX_STAT_AMPDU to
be set so that mac80211 can report the last_tx_rate correctly.

Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:54 -04:00
Fariya Fatima
d453ba81cd rsi: Fixed issue relating to doing dma on stack error.
Signed-off-by: Fariya Fatima <fariyaf@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:54 -04:00
Fariya Fatima
5156fd24e9 rsi: Fixed issue relating to index of q_num.
Signed-off-by: Fariya Fatima <fariyaf@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:54 -04:00
Fariya Fatima
d50c761aef rsi: Fixed issue relating to return value.
Signed-off-by: Fariya Fatima <fariyaf@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:54 -04:00
Fariya Fatima
57a2a093b4 rsi: Fixed issue relating to variable de-referenced before check 'adapter'
Signed-off-by: Fariya Fatima <fariyaf@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:53 -04:00
Fariya Fatima
bff37af7f2 rsi: Fixed signedness bug reported by static code analyzer.
Signed-off-by: Fariya Fatima <fariyaf@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:53 -04:00
Fariya Fatima
b25e77fdfa rsi: Potential null pointer derefernce issue fixed.
Signed-off-by: Fariya Fatima <fariyaf@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-04-09 13:55:53 -04:00
Balakumaran Kannan
fa8cddaf90 net phylib: Remove unnecessary condition check in phy
This condition check makes no difference in the code flow since 3.10

Signed-off-by: Balakumaran Kannan <kumaran.4353@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-09 13:03:53 -04:00
Daniel Borkmann
1e1cdf8ac7 net: sctp: test if association is dead in sctp_wake_up_waiters
In function sctp_wake_up_waiters(), we need to involve a test
if the association is declared dead. If so, we don't have any
reference to a possible sibling association anymore and need
to invoke sctp_write_space() instead, and normally walk the
socket's associations and notify them of new wmem space. The
reason for special casing is that otherwise, we could run
into the following issue when a sctp_primitive_SEND() call
from sctp_sendmsg() fails, and tries to flush an association's
outq, i.e. in the following way:

sctp_association_free()
`-> list_del(&asoc->asocs)         <-- poisons list pointer
    asoc->base.dead = true
    sctp_outq_free(&asoc->outqueue)
    `-> __sctp_outq_teardown()
     `-> sctp_chunk_free()
      `-> consume_skb()
       `-> sctp_wfree()
        `-> sctp_wake_up_waiters() <-- dereferences poisoned pointers
                                       if asoc->ep->sndbuf_policy=0

Therefore, only walk the list in an 'optimized' way if we find
that the current association is still active. We could also use
list_del_init() in addition when we call sctp_association_free(),
but as Vlad suggests, we want to trap such bugs and thus leave
it poisoned as is.

Why is it safe to resolve the issue by testing for asoc->base.dead?
Parallel calls to sctp_sendmsg() are protected under socket lock,
that is lock_sock()/release_sock(). Only within that path under
lock held, we're setting skb/chunk owner via sctp_set_owner_w().
Eventually, chunks are freed directly by an association still
under that lock. So when traversing association list on destruction
time from sctp_wake_up_waiters() via sctp_wfree(), a different
CPU can't be running sctp_wfree() while another one calls
sctp_association_free() as both happens under the same lock.
Therefore, this can also not race with setting/testing against
asoc->base.dead as we are guaranteed for this to happen in order,
under lock. Further, Vlad says: the times we check asoc->base.dead
is when we've cached an association pointer for later processing.
In between cache and processing, the association may have been
freed and is simply still around due to reference counts. We check
asoc->base.dead under a lock, so it should always be safe to check
and not race against sctp_association_free(). Stress-testing seems
fine now, too.

Fixes: cd253f9f357d ("net: sctp: wake up all assocs if sndbuf policy is per socket")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Vlad Yasevich <vyasevic@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-09 12:37:49 -04:00
Takashi Iwai
50487c3a4a ASoC: Fixes for v3.15
A smattering of device specific fixes, nothing stands out here except
 for the multiplatform fixes for Samsung and the device IDs being added
 by Stephen Warren - there's no real code changes from those and they
 give better robustness to the enumeration with DT.
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Merge tag 'asoc-v3.15-5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v3.15

A smattering of device specific fixes, nothing stands out here except
for the multiplatform fixes for Samsung and the device IDs being added
by Stephen Warren - there's no real code changes from those and they
give better robustness to the enumeration with DT.
2014-04-09 17:50:02 +02:00
Linus Torvalds
39de65aa2c Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Here is the pull request from the i2c subsystem.  It got a little
  delayed because I needed to wait for a dependency to be included
  (commit b424080a9e: "reset: Add optional resets and stubs").  Plus,
  I had some email problems.  All done now, the highlights are:

   - drivers can now deprecate their use of i2c classes.  That shouldn't
     be used on embedded platforms anyhow and was often blindly
     copy&pasted.  This mechanism gives users time to switch away and
     ultimately boot faster once the use of classes for those drivers is
     gone for good.

   - new drivers for QUP, Cadence, efm32

   - tracepoint support for I2C and SMBus

   - bigger cleanups for the mv64xxx, nomadik, and designware drivers

  And the usual bugfixes, cleanups, feature additions.  Most stuff has
  been in linux-next for a while.  Just some hot fixes and new drivers
  were added a bit more recently."

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (63 commits)
  i2c: cadence: fix Kconfig dependency
  i2c: Add driver for Cadence I2C controller
  i2c: cadence: Document device tree bindings
  Documentation: i2c: improve section about flags mangling the protocol
  i2c: qup: use proper type fro clk_freq
  i2c: qup: off by ones in qup_i2c_probe()
  i2c: efm32: fix binding doc
  MAINTAINERS: update I2C web resources
  i2c: qup: New bus driver for the Qualcomm QUP I2C controller
  i2c: qup: Add device tree bindings information
  i2c: i2c-xiic: deprecate class based instantiation
  i2c: i2c-sirf: deprecate class based instantiation
  i2c: i2c-mv64xxx: deprecate class based instantiation
  i2c: i2c-designware-platdrv: deprecate class based instantiation
  i2c: i2c-davinci: deprecate class based instantiation
  i2c: i2c-bcm2835: deprecate class based instantiation
  i2c: mv64xxx: Fix reset controller handling
  i2c: omap: fix usage of IS_ERR_VALUE with pm_runtime_get_sync
  i2c: efm32: new bus driver
  i2c: exynos5: remove unnecessary cast of void pointer
  ...
2014-04-09 08:45:40 -07:00
Linus Torvalds
97e18dc007 MMC highlights for 3.15:
Core:
  - CONFIG_MMC_UNSAFE_RESUME=y is now default behavior.
  - DT bindings for SDHCI UHS, eMMC HS200, high-speed DDR, at 1.8/1.2V.
  - Add GPIO descriptor based slot-gpio card detect API.
 
 Drivers:
  - dw_mmc: Refactor SOCFPGA support as a variant inside dw_mmc-pltfm.c.
  - mmci: Support HW busy detection on ux500.
  - omap: Support MMC_ERASE.
  - omap_hsmmc: Support MMC_PM_KEEP_POWER, MMC_PM_WAKE_SDIO_IRQ, (a)cmd23.
  - rtsx: Support pre-req/post-req async.
  - sdhci: Add support for Realtek RTS5250 controllers.
  - sdhci-acpi: Add support for 80860F16, fix 80860F14/SDIO card detect.
  - sdhci-msm: Add new driver for Qualcomm SDHCI chipset support.
  - sdhci-pxav3: Add support for Marvell Armada 380 and 385 SoCs.
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Merge tag 'mmc-updates-for-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc

Pull MMC updates from Chris Ball:
 "MMC highlights for 3.15:

  Core:
   - CONFIG_MMC_UNSAFE_RESUME=y is now default behavior
   - DT bindings for SDHCI UHS, eMMC HS200, high-speed DDR, at 1.8/1.2V
   - Add GPIO descriptor based slot-gpio card detect API

  Drivers:
   - dw_mmc: Refactor SOCFPGA support as a variant inside dw_mmc-pltfm.c
   - mmci: Support HW busy detection on ux500
   - omap: Support MMC_ERASE
   - omap_hsmmc: Support MMC_PM_KEEP_POWER, MMC_PM_WAKE_SDIO_IRQ, (a)cmd23
   - rtsx: Support pre-req/post-req async
   - sdhci: Add support for Realtek RTS5250 controllers
   - sdhci-acpi: Add support for 80860F16, fix 80860F14/SDIO card detect
   - sdhci-msm: Add new driver for Qualcomm SDHCI chipset support
   - sdhci-pxav3: Add support for Marvell Armada 380 and 385 SoCs"

* tag 'mmc-updates-for-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (102 commits)
  mmc: sdhci-acpi: Intel SDIO has broken card detect
  mmc: sdhci-pxav3: add support for the Armada 38x SDHCI controller
  mmc: sdhci-msm: Add platform_execute_tuning implementation
  mmc: sdhci-msm: Initial support for Qualcomm chipsets
  mmc: sdhci-msm: Qualcomm SDHCI binding documentation
  sdhci: only reprogram retuning timer when flag is set
  mmc: rename ARCH_BCM to ARCH_BCM_MOBILE
  mmc: sdhci: Allow for irq being shared
  mmc: sdhci-acpi: Add device id 80860F16
  mmc: sdhci-acpi: Fix broken card detect for ACPI HID 80860F14
  mmc: slot-gpio: Add GPIO descriptor based CD GPIO API
  mmc: slot-gpio: Split out CD IRQ request into a separate function
  mmc: slot-gpio: Record GPIO descriptors instead of GPIO numbers
  Revert "dts: socfpga: Add support for SD/MMC on the SOCFPGA platform"
  mmc: sdhci-spear: use generic card detection gpio support
  mmc: sdhci-spear: remove support for power gpio
  mmc: sdhci-spear: simplify resource handling
  mmc: sdhci-spear: fix platform_data usage
  mmc: sdhci-spear: fix error handling paths for DT
  mmc: sdhci-bcm-kona: fix build errors when built-in
  ...
2014-04-09 08:39:39 -07:00
Linus Torvalds
042f7b7cbd Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull more powerpc updates from Ben Herrenschmidt:
 "Here are a few more powerpc things for you.

  So you'll find here the conversion of the two new firmware sysfs
  interfaces to the new API for self-removing files that Greg and Tejun
  introduced, so they can finally remove the old one.

  I'm also reverting the hwmon driver for powernv.  I shouldn't have
  merged it, I got a bit carried away here.  I hadn't realized it was
  never CCed to the relevant maintainer(s) and list(s), and happens to
  have some issues so I'm taking it out and it will come back via the
  proper channels.

  The rest is a bunch of LE fixes (argh, some of the new stuff was
  broken on LE, I really need to start testing LE myself !) and various
  random fixes here and there.

  Finally one bit that's not strictly a fix, which is the HVC OPAL
  change to "kick" the HVC thread when the firmware tells us there is
  new incoming data.  I don't feel like waiting for this one, it's
  simple enough, and it makes a big difference in console responsiveness
  which is good for my nerves"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (26 commits)
  powerpc/powernv Adapt opal-elog and opal-dump to new sysfs_remove_file_self
  Revert "powerpc/powernv: hwmon driver for power values, fan rpm and temperature"
  power, sched: stop updating inside arch_update_cpu_topology() when nothing to be update
  powerpc/le: Avoid creatng R_PPC64_TOCSAVE relocations for modules.
  arch/powerpc: Use RCU_INIT_POINTER(x, NULL) in platforms/cell/spu_syscalls.c
  powerpc/opal: Add missing include
  powerpc: Convert last uses of __FUNCTION__ to __func__
  powerpc: Add lq/stq emulation
  powerpc/powernv: Add invalid OPAL call
  powerpc/powernv: Add OPAL message log interface
  powerpc/book3s: Fix mc_recoverable_range buffer overrun issue.
  powerpc: Remove dead code in sycall entry
  powerpc: Use of_node_init() for the fakenode in msi_bitmap.c
  powerpc/mm: NUMA pte should be handled via slow path in get_user_pages_fast()
  powerpc/powernv: Fix endian issues with sensor code
  powerpc/powernv: Fix endian issues with OPAL async code
  tty/hvc_opal: Kick the HVC thread on OPAL console events
  powerpc/powernv: Add opal_notifier_unregister() and export to modules
  powerpc/ppc64: Do not turn AIL (reloc-on interrupts) too early
  powerpc/ppc64: Gracefully handle early interrupts
  ...
2014-04-09 08:35:31 -07:00
Linus Torvalds
69cd9eba38 futex: avoid race between requeue and wake
Jan Stancek reported:
 "pthread_cond_broadcast/4-1.c testcase from openposix testsuite (LTP)
  occasionally fails, because some threads fail to wake up.

  Testcase creates 5 threads, which are all waiting on same condition.
  Main thread then calls pthread_cond_broadcast() without holding mutex,
  which calls:

      futex(uaddr1, FUTEX_CMP_REQUEUE_PRIVATE, 1, 2147483647, uaddr2, ..)

  This immediately wakes up single thread A, which unlocks mutex and
  tries to wake up another thread:

      futex(uaddr2, FUTEX_WAKE_PRIVATE, 1)

  If thread A manages to call futex_wake() before any waiters are
  requeued for uaddr2, no other thread is woken up"

The ordering constraints for the hash bucket waiter counting are that
the waiter counts have to be incremented _before_ getting the spinlock
(because the spinlock acts as part of the memory barrier), but the
"requeue" operation didn't honor those rules, and nobody had even
thought about that case.

This fairly simple patch just increments the waiter count for the target
hash bucket (hb2) when requeing a futex before taking the locks.  It
then decrements them again after releasing the lock - the code that
actually moves the futex(es) between hash buckets will do the additional
required waiter count housekeeping.

Reported-and-tested-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # 3.14
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-09 08:02:12 -07:00
Mathieu Desnoyers
b725dfea24 tracepoint: Fix sparse warnings in tracepoint.c
Fix the following sparse warnings:

  CHECK   kernel/tracepoint.c
kernel/tracepoint.c:184:18: warning: incorrect type in assignment (different address spaces)
kernel/tracepoint.c:184:18:    expected struct tracepoint_func *tp_funcs
kernel/tracepoint.c:184:18:    got struct tracepoint_func [noderef] <asn:4>*funcs
kernel/tracepoint.c:216:18: warning: incorrect type in assignment (different address spaces)
kernel/tracepoint.c:216:18:    expected struct tracepoint_func *tp_funcs
kernel/tracepoint.c:216:18:    got struct tracepoint_func [noderef] <asn:4>*funcs
kernel/tracepoint.c:392:24: error: return expression in void function
  CC      kernel/tracepoint.o
kernel/tracepoint.c: In function tracepoint_module_going:
kernel/tracepoint.c:491:6: warning: symbol 'syscall_regfunc' was not declared. Should it be static?
kernel/tracepoint.c:508:6: warning: symbol 'syscall_unregfunc' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/1397049883-28692-1-git-send-email-mathieu.desnoyers@efficios.com

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-04-09 10:12:11 -04:00
Martin K. Petersen
e69f18f06b block: Ensure we only enable integrity metadata for reads and writes
We'd occasionally attempt to generate protection information for flushes
and other requests with a zero payload. Make sure we only attempt to
enable integrity for reads and writes.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-09 08:00:06 -06:00
Martin K. Petersen
0bc6997306 block: Fix integrity verification
Commit bf36f9cfa6 caused a regression by effectively reverting Nic's
fix from 5837c80e87 that ensures we traverse the full bio_vec list
upon completion.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-09 08:00:04 -06:00
Martin K. Petersen
b7aa84d9cb block: Fix for_each_bvec()
Commit 4550dd6c6b introduced for_each_bvec() which iterates over each
bvec attached to a bio or bip. However, the macro fails to check bi_size
before dereferencing which can lead to crashes while counting/mapping
integrity scatterlist segments.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-04-09 08:00:01 -06:00
Thierry Reding
17c3ad0302 ALSA: hda - Make full_reset boolean
The full_reset argument to azx_init_chip() carries boolean rather than
numerical information, so update the type to reflect that.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-04-09 14:48:07 +02:00
Catalin Marinas
0b1f68e836 ARM: 8018/1: Add {inc,dec}_preempt_count asm macros
The patch adds asm macros for inc_preempt_count and dec_preempt_count_ti
(which also gets the current thread_info) instead of open-coding them in
arch/arm/vfp/*.S files.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Arun KS <getarunks@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-09 13:08:08 +01:00
Catalin Marinas
39ad04ccd6 ARM: 8017/1: Move asm macro get_thread_info to asm/assembler.h
asm/assembler.h is a better place for this macro since it is used by
asm files outside arch/arm/kernel/

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Arun KS <getarunks@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-09 13:08:07 +01:00
Hui Wang
137bcc33c6 ALSA: hda - add headset mic detect quirk for a Dell laptop
When we plug a 3-ring headset on the Dell machine (VID: 0x10ec0283,
SID: 0x10280667), the headset mic can't be detected, after apply this
patch, the headset mic can work well.

BugLink: https://bugs.launchpad.net/bugs/1297581
Cc: David Henningsson <david.henningsson@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-04-09 10:05:51 +02:00
Christoph Jaeger
292ab81df0 sound: dmasound: use module_platform_driver_probe()
Eliminate boilerplate code by using module_platform_driver_probe().

Signed-off-by: Christoph Jaeger <christophjaeger@linux.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-04-09 10:02:21 +02:00
Christoph Jaeger
34f980630f ALSA: au1x00: use module_platform_driver()
Eliminate boilerplate code by using module_platform_driver().

Signed-off-by: Christoph Jaeger <christophjaeger@linux.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-04-09 10:02:14 +02:00
Dylan Reid
7b0a48f340 ALSA: hda - Use runtime helper to check active state.
From azx_interrupt, use the helper to check if the device is active
instead of checking the state.  This will do the right thing if
runtime pm is disabled in addition to if the device is suspended.

Signed-off-by: Dylan Reid <dgreid@chromium.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-04-09 09:33:03 +02:00
Shaohua Li
e240c1839d raid5: get_active_stripe avoids device_lock
For sequential workload (or request size big workload), get_active_stripe can
find cached stripe. In this case, we always hold device_lock, which exposes a
lot of lock contention for such workload. If stripe count isn't 0, we don't
need hold the lock actually, since we just increase its count. And this is the
hot code path for such workload. Unfortunately we must delete the BUG_ON.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-04-09 14:42:42 +10:00
Shaohua Li
27c0f68f07 raid5: make_request does less prepare wait
In NUMA machine, prepare_to_wait/finish_wait in make_request exposes a
lot of contention for sequential workload (or big request size
workload). For such workload, each bio includes several stripes. So we
can just do prepare_to_wait/finish_wait once for the whold bio instead
of every stripe.  This reduces the lock contention completely for such
workload. Random workload might have the similar lock contention too,
but I didn't see it yet, maybe because my stroage is still not fast
enough.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-04-09 14:42:38 +10:00
NeilBrown
e2f23b606b md: avoid oops on unload if some process is in poll or select.
If md-mod is unloaded while some process is in poll() or select(),
then that process maintains a pointer to md_event_waiters, and when
the try to unlink from that list, they will oops.

The procfs infrastructure ensures that ->poll won't be called after
remove_proc_entry, but doesn't provide a wait_queue_head for us to
use, and the waitqueue code doesn't provide a way to remove all
listeners from a waitqueue.

So we need to:
 1/ make sure no further references to md_event_waiters are taken (by
    setting md_unloading)
 2/ wake up all processes currently waiting, and
 3/ wait until all those processes have disconnected from our
    wait_queue_head.

Reported-by: "majianpeng" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-04-09 14:42:34 +10:00