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Heiner Kallweit c1305a4072 [media] rc: nuvoton: fix deadlock in nvt_write_wakeup_codes
nvt_write_wakeup_codes acquires the same lock as the ISR but doesn't
disable interrupts on the local CPU. This caused the following
deadlock. Fix this by using spin_lock_irqsave.

[  432.362008] ================================
[  432.362074] WARNING: inconsistent lock state
[  432.362144] 4.10.0-rc7-next-20170210 #1 Not tainted
[  432.362219] --------------------------------
[  432.362286] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
[  432.362379] swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
[  432.362457]  (&(&nvt->lock)->rlock){?.+...}, at: [<ffffffffa016b17d>] nvt_cir_isr+0x2d/0x520 [nuvoton_cir]
[  432.362611] {HARDIRQ-ON-W} state was registered at:
[  432.362686]
[  432.362698] [<ffffffff810adb7c>] __lock_acquire+0x5dc/0x1260
[  432.362812]
[  432.362817] [<ffffffff810aec29>] lock_acquire+0xe9/0x1d0
[  432.362927]
[  432.362934] [<ffffffff81609f63>] _raw_spin_lock+0x33/0x50
[  432.363045]
[  432.363051] [<ffffffffa016b822>] nvt_write_wakeup_codes.isra.12+0x22/0xe0 [nuvoton_cir]
[  432.363193]
[  432.363199] [<ffffffffa016b9bf>] wakeup_data_store+0xdf/0xf0 [nuvoton_cir]
[  432.363327]
[  432.363333] [<ffffffff81484223>] dev_attr_store+0x13/0x20
[  432.363441]
[  432.363449] [<ffffffff81232450>] sysfs_kf_write+0x40/0x50
[  432.363558]
[  432.363564] [<ffffffff81231640>] kernfs_fop_write+0x150/0x1e0
[  432.363676]
[  432.363685] [<ffffffff811b36a3>] __vfs_write+0x23/0x120
[  432.363791]
[  432.363798] [<ffffffff811b4d53>] vfs_write+0xc3/0x1e0
[  432.363902]
[  432.363909] [<ffffffff811b6124>] SyS_write+0x44/0xa0
[  432.364012]
[  432.364021] [<ffffffff81002c47>] do_syscall_64+0x57/0x140
[  432.364129]
[  432.364135] [<ffffffff8160a9e4>] return_from_SYSCALL_64+0x0/0x7a
[  432.364252] irq event stamp: 415118
[  432.364313] hardirqs last  enabled at (415115): [<ffffffff814fd2eb>] cpuidle_enter_state+0x11b/0x370
[  432.364445] hardirqs last disabled at (415116): [<ffffffff8160b2cb>] common_interrupt+0x8b/0x90
[  432.364573] softirqs last  enabled at (415118): [<ffffffff8106157c>] _local_bh_enable+0x1c/0x50
[  432.364699] softirqs last disabled at (415117): [<ffffffff810629a3>] irq_enter+0x43/0x60
[  432.364814]
               other info that might help us debug this:
[  432.364909]  Possible unsafe locking scenario:

[  432.367821]        CPU0
[  432.370645]        ----
[  432.373432]   lock(&(&nvt->lock)->rlock);
[  432.376228]   <Interrupt>
[  432.378982]     lock(&(&nvt->lock)->rlock);
[  432.381757]
                *** DEADLOCK ***

[  432.389888] no locks held by swapper/0/0.
[  432.392574]
               stack backtrace:
[  432.397774] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.10.0-rc7-next-20170210 #1
[  432.400375] Hardware name: ZOTAC ZBOX-CI321NANO/ZBOX-CI321NANO, BIOS B246P105 06/01/2015
[  432.403023] Call Trace:
[  432.405636]  <IRQ>
[  432.408208]  dump_stack+0x68/0x93
[  432.410775]  print_usage_bug+0x1dd/0x1f0
[  432.413334]  mark_lock+0x559/0x5c0
[  432.415871]  ? print_shortest_lock_dependencies+0x1a0/0x1a0
[  432.418431]  __lock_acquire+0x6b1/0x1260
[  432.420941]  lock_acquire+0xe9/0x1d0
[  432.423396]  ? nvt_cir_isr+0x2d/0x520 [nuvoton_cir]
[  432.425844]  _raw_spin_lock+0x33/0x50
[  432.428252]  ? nvt_cir_isr+0x2d/0x520 [nuvoton_cir]
[  432.430670]  nvt_cir_isr+0x2d/0x520 [nuvoton_cir]
[  432.433085]  __handle_irq_event_percpu+0x43/0x330
[  432.435493]  handle_irq_event_percpu+0x1e/0x50
[  432.437884]  handle_irq_event+0x34/0x60
[  432.440236]  handle_edge_irq+0x6a/0x150
[  432.442561]  handle_irq+0x15/0x20
[  432.444854]  do_IRQ+0x57/0x110
[  432.447115]  common_interrupt+0x90/0x90
[  432.449380] RIP: 0010:cpuidle_enter_state+0x120/0x370
[  432.451653] RSP: 0018:ffffffff81c03dd8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffffcc
[  432.453994] RAX: ffffffff81c14500 RBX: 0000000000000008 RCX: 00000064aac6f2d2
[  432.456349] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff81c14500
[  432.458704] RBP: ffffffff81c03e18 R08: cccccccccccccccd R09: 0000000000000018
[  432.461072] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880100a21260
[  432.463450] R13: ffffffff81c7e6f8 R14: 0000000000000008 R15: ffffffff81c7e6e0
[  432.465819]  </IRQ>
[  432.468104]  ? cpuidle_enter_state+0x11b/0x370
[  432.470413]  cpuidle_enter+0x12/0x20
[  432.472698]  call_cpuidle+0x1e/0x40
[  432.474967]  do_idle+0xe3/0x1c0
[  432.477172]  cpu_startup_entry+0x18/0x20
[  432.479376]  rest_init+0x130/0x140
[  432.481565]  start_kernel+0x3cc/0x3d9
[  432.483750]  x86_64_start_reservations+0x2a/0x2c
[  432.485980]  x86_64_start_kernel+0x178/0x18b
[  432.488222]  start_cpu+0x14/0x14
[  432.490453]  ? start_cpu+0x14/0x14

Fixes: 97c129747a "[media] rc: nuvoton-cir: Add support wakeup via sysfs filter callback"

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-03-03 07:06:57 -03:00
arch [media] ARM: multi_v7_defconfig: enable STMicroelectronics DELTA Support 2017-02-08 09:57:37 -02:00
block ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
certs certs: Add a secondary system keyring that can be added to dynamically 2016-04-11 22:48:09 +01:00
crypto This pull contains one set of changes: a conversion of the crypto DocBook 2016-12-17 16:00:34 -08:00
Documentation [media] Documentation: DT: add bindings for ST DELTA 2017-02-08 09:56:47 -02:00
drivers [media] rc: nuvoton: fix deadlock in nvt_write_wakeup_codes 2017-03-03 07:06:57 -03:00
firmware WHENCE: use https://linuxtv.org for LinuxTV URLs 2015-12-04 10:35:11 -02:00
fs ktime: Get rid of ktime_equal() 2016-12-25 17:21:23 +01:00
include [media] v4l2-subdev.h: fix v4l2_subdev_pad_config documentation 2017-02-03 12:00:37 -02:00
init mm: add PageWaiters indicating tasks are waiting for a page bit 2016-12-25 11:54:48 -08:00
ipc ipc/sem: avoid idr tree lookup for interrupted semop 2016-12-14 16:04:08 -08:00
kernel Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-25 14:30:04 -08:00
lib Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-25 14:30:04 -08:00
mm mm: add PageWaiters indicating tasks are waiting for a page bit 2016-12-25 11:54:48 -08:00
net ktime: Get rid of ktime_equal() 2016-12-25 17:21:23 +01:00
samples Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-23 16:49:12 -08:00
scripts Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-12-22 10:03:52 -08:00
security Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
sound ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
tools Merge branch 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2016-12-25 14:01:28 -08:00
usr initramfs: allow again choice of the embedded initram compression algorithm 2016-12-14 16:04:08 -08:00
virt Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-25 14:30:04 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-08-02 16:48:52 -04:00
.mailmap Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-10-15 09:26:12 -07:00
COPYING
CREDITS CREDITS: Remove outdated address information 2016-12-21 15:21:29 -08:00
Kbuild scripts/gdb: provide linux constants 2016-05-23 17:04:14 -07:00
Kconfig kbuild: migrate all arch to the kconfig mainmenu upgrade 2010-09-19 22:54:11 -04:00
MAINTAINERS [media] MAINTAINERS: add st-delta driver 2017-02-08 09:57:55 -02:00
Makefile Linux 4.10-rc1 2016-12-25 16:13:08 -08:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.