<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include, branch v3.16.74</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v3.16.74</id>
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<updated>2019-09-23T20:12:16Z</updated>
<entry>
<title>appletalk: Fix compile regression</title>
<updated>2019-09-23T20:12:16Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2019-03-06T10:52:36Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8a8b481d1908d18213a55260498c5b0af6f12892'/>
<id>urn:sha1:8a8b481d1908d18213a55260498c5b0af6f12892</id>
<content type='text'>
commit 27da0d2ef998e222a876c0cec72aa7829a626266 upstream.

A bugfix just broke compilation of appletalk when CONFIG_SYSCTL
is disabled:

In file included from net/appletalk/ddp.c:65:
net/appletalk/ddp.c: In function 'atalk_init':
include/linux/atalk.h:164:34: error: expected expression before 'do'
 #define atalk_register_sysctl()  do { } while(0)
                                  ^~
net/appletalk/ddp.c:1934:7: note: in expansion of macro 'atalk_register_sysctl'
  rc = atalk_register_sysctl();

This is easier to avoid by using conventional inline functions
as stubs rather than macros. The header already has inline
functions for other purposes, so I'm changing over all the
macros for consistency.

Fixes: 6377f787aeb9 ("appletalk: Fix use-after-free in atalk_proc_exit")
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>appletalk: Fix use-after-free in atalk_proc_exit</title>
<updated>2019-09-23T20:12:15Z</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2019-03-01T02:57:57Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2714dac820ef997b8d225eba6788b69cf8398464'/>
<id>urn:sha1:2714dac820ef997b8d225eba6788b69cf8398464</id>
<content type='text'>
commit 6377f787aeb945cae7abbb6474798de129e1f3ac upstream.

KASAN report this:

BUG: KASAN: use-after-free in pde_subdir_find+0x12d/0x150 fs/proc/generic.c:71
Read of size 8 at addr ffff8881f41fe5b0 by task syz-executor.0/2806

CPU: 0 PID: 2806 Comm: syz-executor.0 Not tainted 5.0.0-rc7+ #45
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xfa/0x1ce lib/dump_stack.c:113
 print_address_description+0x65/0x270 mm/kasan/report.c:187
 kasan_report+0x149/0x18d mm/kasan/report.c:317
 pde_subdir_find+0x12d/0x150 fs/proc/generic.c:71
 remove_proc_entry+0xe8/0x420 fs/proc/generic.c:667
 atalk_proc_exit+0x18/0x820 [appletalk]
 atalk_exit+0xf/0x5a [appletalk]
 __do_sys_delete_module kernel/module.c:1018 [inline]
 __se_sys_delete_module kernel/module.c:961 [inline]
 __x64_sys_delete_module+0x3dc/0x5e0 kernel/module.c:961
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb2de6b9c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200001c0
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb2de6ba6bc
R13: 00000000004bccaa R14: 00000000006f6bc8 R15: 00000000ffffffff

Allocated by task 2806:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:496
 slab_post_alloc_hook mm/slab.h:444 [inline]
 slab_alloc_node mm/slub.c:2739 [inline]
 slab_alloc mm/slub.c:2747 [inline]
 kmem_cache_alloc+0xcf/0x250 mm/slub.c:2752
 kmem_cache_zalloc include/linux/slab.h:730 [inline]
 __proc_create+0x30f/0xa20 fs/proc/generic.c:408
 proc_mkdir_data+0x47/0x190 fs/proc/generic.c:469
 0xffffffffc10c01bb
 0xffffffffc10c0166
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 2806:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:458
 slab_free_hook mm/slub.c:1409 [inline]
 slab_free_freelist_hook mm/slub.c:1436 [inline]
 slab_free mm/slub.c:2986 [inline]
 kmem_cache_free+0xa6/0x2a0 mm/slub.c:3002
 pde_put+0x6e/0x80 fs/proc/generic.c:647
 remove_proc_entry+0x1d3/0x420 fs/proc/generic.c:684
 0xffffffffc10c031c
 0xffffffffc10c0166
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881f41fe500
 which belongs to the cache proc_dir_entry of size 256
The buggy address is located 176 bytes inside of
 256-byte region [ffff8881f41fe500, ffff8881f41fe600)
The buggy address belongs to the page:
page:ffffea0007d07f80 count:1 mapcount:0 mapping:ffff8881f6e69a00 index:0x0
flags: 0x2fffc0000000200(slab)
raw: 02fffc0000000200 dead000000000100 dead000000000200 ffff8881f6e69a00
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881f41fe480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881f41fe500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
&gt;ffff8881f41fe580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8881f41fe600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8881f41fe680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

It should check the return value of atalk_proc_init fails,
otherwise atalk_exit will trgger use-after-free in pde_subdir_find
while unload the module.This patch fix error cleanup path of atalk_init

Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>mac80211: add API to request TDLS operation from userspace</title>
<updated>2019-09-23T20:12:09Z</updated>
<author>
<name>Arik Nemtsov</name>
<email>arik@wizery.com</email>
</author>
<published>2014-06-11T14:18:25Z</published>
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<id>urn:sha1:4ddb257573f61238bca2e3482e2f9cd94627f936</id>
<content type='text'>
commit c887f0d3a03283cb6fe2c32aae62229bebd3fa32 upstream.

Write a mac80211 to the cfg80211 API for requesting a userspace TDLS
operation. Define TDLS specific reason codes that can be used here.

Signed-off-by: Arik Nemtsov &lt;arikx.nemtsov@intel.com&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>mfd: da9063: Fix OTP control register names to match datasheets for DA9063/63L</title>
<updated>2019-09-23T20:12:05Z</updated>
<author>
<name>Steve Twiss</name>
<email>stwiss.opensource@diasemi.com</email>
</author>
<published>2019-04-26T13:33:35Z</published>
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<id>urn:sha1:5aa0b508145ff5a8a339aaad14ce9632b262c7e4</id>
<content type='text'>
commit 6b4814a9451add06d457e198be418bf6a3e6a990 upstream.

Mismatch between what is found in the Datasheets for DA9063 and DA9063L
provided by Dialog Semiconductor, and the register names provided in the
MFD registers file. The changes are for the OTP (one-time-programming)
control registers. The two naming errors are OPT instead of OTP, and
COUNT instead of CONT (i.e. control).

Signed-off-by: Steve Twiss &lt;stwiss.opensource@diasemi.com&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>media: davinci/vpbe: array underflow in vpbe_enum_outputs()</title>
<updated>2019-09-23T20:12:02Z</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2019-04-24T09:46:27Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=993b03c917d72759a638b266ceb5652a1ee84dc7'/>
<id>urn:sha1:993b03c917d72759a638b266ceb5652a1ee84dc7</id>
<content type='text'>
commit b72845ee5577b227131b1fef23f9d9a296621d7b upstream.

In vpbe_enum_outputs() we check if (temp_index &gt;= cfg-&gt;num_outputs) but
the problem is that "temp_index" can be negative.  This patch changes
the types to unsigned to address this array underflow bug.

Fixes: 66715cdc3224 ("[media] davinci vpbe: VPBE display driver")

Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Acked-by: "Lad, Prabhakar" &lt;prabhakar.csengg@gmail.com&gt;
Signed-off-by: Hans Verkuil &lt;hverkuil-cisco@xs4all.nl&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab+samsung@kernel.org&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>of: fix clang -Wunsequenced for be32_to_cpu()</title>
<updated>2019-09-23T20:11:57Z</updated>
<author>
<name>Phong Tran</name>
<email>tranmanphong@gmail.com</email>
</author>
<published>2019-04-30T14:56:24Z</published>
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<id>urn:sha1:8939c50855f40af4963daf1550b30923052ba599</id>
<content type='text'>
commit 440868661f36071886ed360d91de83bd67c73b4f upstream.

Now, make the loop explicit to avoid clang warning.

./include/linux/of.h:238:37: warning: multiple unsequenced modifications
to 'cell' [-Wunsequenced]
                r = (r &lt;&lt; 32) | be32_to_cpu(*(cell++));
                                                  ^~
./include/linux/byteorder/generic.h:95:21: note: expanded from macro
'be32_to_cpu'
                    ^
./include/uapi/linux/byteorder/little_endian.h:40:59: note: expanded
from macro '__be32_to_cpu'
                                                          ^
./include/uapi/linux/swab.h:118:21: note: expanded from macro '__swab32'
        ___constant_swab32(x) :                 \
                           ^
./include/uapi/linux/swab.h:18:12: note: expanded from macro
'___constant_swab32'
        (((__u32)(x) &amp; (__u32)0x000000ffUL) &lt;&lt; 24) |            \
                  ^

Signed-off-by: Phong Tran &lt;tranmanphong@gmail.com&gt;
Reported-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Link: https://github.com/ClangBuiltLinux/linux/issues/460
Suggested-by: David Laight &lt;David.Laight@ACULAB.COM&gt;
Reviewed-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
[robh: fix up whitespace]
Signed-off-by: Rob Herring &lt;robh@kernel.org&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>Bluetooth: Align minimum encryption key size for LE and BR/EDR connections</title>
<updated>2019-09-23T20:11:50Z</updated>
<author>
<name>Marcel Holtmann</name>
<email>marcel@holtmann.org</email>
</author>
<published>2019-04-24T20:19:17Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=1f52c0fb870d0a3e00f790d5a8085bcb234ad0fe'/>
<id>urn:sha1:1f52c0fb870d0a3e00f790d5a8085bcb234ad0fe</id>
<content type='text'>
commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream.

The minimum encryption key size for LE connections is 56 bits and to
align LE with BR/EDR, enforce 56 bits of minimum encryption key size for
BR/EDR connections as well.

Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Johan Hedberg &lt;johan.hedberg@intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>smpboot: Place the __percpu annotation correctly</title>
<updated>2019-09-23T20:11:46Z</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2019-04-24T08:52:53Z</published>
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<id>urn:sha1:c241753cac92a58f69c62110620f773e11c9f64b</id>
<content type='text'>
commit d4645d30b50d1691c26ff0f8fa4e718b08f8d3bb upstream.

The test robot reported a wrong assignment of a per-CPU variable which
it detected by using sparse and sent a report. The assignment itself is
correct. The annotation for sparse was wrong and hence the report.
The first pointer is a "normal" pointer and points to the per-CPU memory
area. That means that the __percpu annotation has to be moved.

Move the __percpu annotation to pointer which points to the per-CPU
area. This change affects only the sparse tool (and is ignored by the
compiler).

Reported-by: kbuild test robot &lt;lkp@intel.com&gt;
Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.ibm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: f97f8f06a49fe ("smpboot: Provide infrastructure for percpu hotplug threads")
Link: http://lkml.kernel.org/r/20190424085253.12178-1-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum</title>
<updated>2019-09-23T20:11:39Z</updated>
<author>
<name>Stefan Mätje</name>
<email>stefan.maetje@esd.eu</email>
</author>
<published>2019-03-29T17:07:35Z</published>
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<id>urn:sha1:57b9ed53b9ade4b1bb4950eafd21ccb0fb46a6db</id>
<content type='text'>
commit 4ec73791a64bab25cabf16a6067ee478692e506d upstream.

Due to an erratum in some Pericom PCIe-to-PCI bridges in reverse mode
(conventional PCI on primary side, PCIe on downstream side), the Retrain
Link bit needs to be cleared manually to allow the link training to
complete successfully.

If it is not cleared manually, the link training is continuously restarted
and no devices below the PCI-to-PCIe bridge can be accessed.  That means
drivers for devices below the bridge will be loaded but won't work and may
even crash because the driver is only reading 0xffff.

See the Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf for
details.  Devices known as affected so far are: PI7C9X110, PI7C9X111SL,
PI7C9X130.

Add a new flag, clear_retrain_link, in struct pci_dev.  Quirks for affected
devices set this bit.

Note that pcie_retrain_link() lives in aspm.c because that's currently the
only place we use it, but this erratum is not specific to ASPM, and we may
retrain links for other reasons in the future.

Signed-off-by: Stefan Mätje &lt;stefan.maetje@esd.eu&gt;
[bhelgaas: apply regardless of CONFIG_PCIEASPM]
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
[bwh: Backported to 3.16:
 - Use dev_info() instead of pci_info()
 - Adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
<entry>
<title>pwm: Fix deadlock warning when removing PWM device</title>
<updated>2019-09-23T20:11:34Z</updated>
<author>
<name>Phong Hoang</name>
<email>phong.hoang.wz@renesas.com</email>
</author>
<published>2019-03-19T10:40:08Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=811f5bba33330cb071bba3532ff6f81718b20af7'/>
<id>urn:sha1:811f5bba33330cb071bba3532ff6f81718b20af7</id>
<content type='text'>
commit 347ab9480313737c0f1aaa08e8f2e1a791235535 upstream.

This patch fixes deadlock warning if removing PWM device
when CONFIG_PROVE_LOCKING is enabled.

This issue can be reproceduced by the following steps on
the R-Car H3 Salvator-X board if the backlight is disabled:

 # cd /sys/class/pwm/pwmchip0
 # echo 0 &gt; export
 # ls
 device  export  npwm  power  pwm0  subsystem  uevent  unexport
 # cd device/driver
 # ls
 bind  e6e31000.pwm  uevent  unbind
 # echo e6e31000.pwm &gt; unbind

[   87.659974] ======================================================
[   87.666149] WARNING: possible circular locking dependency detected
[   87.672327] 5.0.0 #7 Not tainted
[   87.675549] ------------------------------------------------------
[   87.681723] bash/2986 is trying to acquire lock:
[   87.686337] 000000005ea0e178 (kn-&gt;count#58){++++}, at: kernfs_remove_by_name_ns+0x50/0xa0
[   87.694528]
[   87.694528] but task is already holding lock:
[   87.700353] 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c
[   87.707405]
[   87.707405] which lock already depends on the new lock.
[   87.707405]
[   87.715574]
[   87.715574] the existing dependency chain (in reverse order) is:
[   87.723048]
[   87.723048] -&gt; #1 (pwm_lock){+.+.}:
[   87.728017]        __mutex_lock+0x70/0x7e4
[   87.732108]        mutex_lock_nested+0x1c/0x24
[   87.736547]        pwm_request_from_chip.part.6+0x34/0x74
[   87.741940]        pwm_request_from_chip+0x20/0x40
[   87.746725]        export_store+0x6c/0x1f4
[   87.750820]        dev_attr_store+0x18/0x28
[   87.754998]        sysfs_kf_write+0x54/0x64
[   87.759175]        kernfs_fop_write+0xe4/0x1e8
[   87.763615]        __vfs_write+0x40/0x184
[   87.767619]        vfs_write+0xa8/0x19c
[   87.771448]        ksys_write+0x58/0xbc
[   87.775278]        __arm64_sys_write+0x18/0x20
[   87.779721]        el0_svc_common+0xd0/0x124
[   87.783986]        el0_svc_compat_handler+0x1c/0x24
[   87.788858]        el0_svc_compat+0x8/0x18
[   87.792947]
[   87.792947] -&gt; #0 (kn-&gt;count#58){++++}:
[   87.798260]        lock_acquire+0xc4/0x22c
[   87.802353]        __kernfs_remove+0x258/0x2c4
[   87.806790]        kernfs_remove_by_name_ns+0x50/0xa0
[   87.811836]        remove_files.isra.1+0x38/0x78
[   87.816447]        sysfs_remove_group+0x48/0x98
[   87.820971]        sysfs_remove_groups+0x34/0x4c
[   87.825583]        device_remove_attrs+0x6c/0x7c
[   87.830197]        device_del+0x11c/0x33c
[   87.834201]        device_unregister+0x14/0x2c
[   87.838638]        pwmchip_sysfs_unexport+0x40/0x4c
[   87.843509]        pwmchip_remove+0xf4/0x13c
[   87.847773]        rcar_pwm_remove+0x28/0x34
[   87.852039]        platform_drv_remove+0x24/0x64
[   87.856651]        device_release_driver_internal+0x18c/0x21c
[   87.862391]        device_release_driver+0x14/0x1c
[   87.867175]        unbind_store+0xe0/0x124
[   87.871265]        drv_attr_store+0x20/0x30
[   87.875442]        sysfs_kf_write+0x54/0x64
[   87.879618]        kernfs_fop_write+0xe4/0x1e8
[   87.884055]        __vfs_write+0x40/0x184
[   87.888057]        vfs_write+0xa8/0x19c
[   87.891887]        ksys_write+0x58/0xbc
[   87.895716]        __arm64_sys_write+0x18/0x20
[   87.900154]        el0_svc_common+0xd0/0x124
[   87.904417]        el0_svc_compat_handler+0x1c/0x24
[   87.909289]        el0_svc_compat+0x8/0x18
[   87.913378]
[   87.913378] other info that might help us debug this:
[   87.913378]
[   87.921374]  Possible unsafe locking scenario:
[   87.921374]
[   87.927286]        CPU0                    CPU1
[   87.931808]        ----                    ----
[   87.936331]   lock(pwm_lock);
[   87.939293]                                lock(kn-&gt;count#58);
[   87.945120]                                lock(pwm_lock);
[   87.950599]   lock(kn-&gt;count#58);
[   87.953908]
[   87.953908]  *** DEADLOCK ***
[   87.953908]
[   87.959821] 4 locks held by bash/2986:
[   87.963563]  #0: 00000000ace7bc30 (sb_writers#6){.+.+}, at: vfs_write+0x188/0x19c
[   87.971044]  #1: 00000000287991b2 (&amp;of-&gt;mutex){+.+.}, at: kernfs_fop_write+0xb4/0x1e8
[   87.978872]  #2: 00000000f739d016 (&amp;dev-&gt;mutex){....}, at: device_release_driver_internal+0x40/0x21c
[   87.988001]  #3: 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c
[   87.995481]
[   87.995481] stack backtrace:
[   87.999836] CPU: 0 PID: 2986 Comm: bash Not tainted 5.0.0 #7
[   88.005489] Hardware name: Renesas Salvator-X board based on r8a7795 ES1.x (DT)
[   88.012791] Call trace:
[   88.015235]  dump_backtrace+0x0/0x190
[   88.018891]  show_stack+0x14/0x1c
[   88.022204]  dump_stack+0xb0/0xec
[   88.025514]  print_circular_bug.isra.32+0x1d0/0x2e0
[   88.030385]  __lock_acquire+0x1318/0x1864
[   88.034388]  lock_acquire+0xc4/0x22c
[   88.037958]  __kernfs_remove+0x258/0x2c4
[   88.041874]  kernfs_remove_by_name_ns+0x50/0xa0
[   88.046398]  remove_files.isra.1+0x38/0x78
[   88.050487]  sysfs_remove_group+0x48/0x98
[   88.054490]  sysfs_remove_groups+0x34/0x4c
[   88.058580]  device_remove_attrs+0x6c/0x7c
[   88.062671]  device_del+0x11c/0x33c
[   88.066154]  device_unregister+0x14/0x2c
[   88.070070]  pwmchip_sysfs_unexport+0x40/0x4c
[   88.074421]  pwmchip_remove+0xf4/0x13c
[   88.078163]  rcar_pwm_remove+0x28/0x34
[   88.081906]  platform_drv_remove+0x24/0x64
[   88.085996]  device_release_driver_internal+0x18c/0x21c
[   88.091215]  device_release_driver+0x14/0x1c
[   88.095478]  unbind_store+0xe0/0x124
[   88.099048]  drv_attr_store+0x20/0x30
[   88.102704]  sysfs_kf_write+0x54/0x64
[   88.106359]  kernfs_fop_write+0xe4/0x1e8
[   88.110275]  __vfs_write+0x40/0x184
[   88.113757]  vfs_write+0xa8/0x19c
[   88.117065]  ksys_write+0x58/0xbc
[   88.120374]  __arm64_sys_write+0x18/0x20
[   88.124291]  el0_svc_common+0xd0/0x124
[   88.128034]  el0_svc_compat_handler+0x1c/0x24
[   88.132384]  el0_svc_compat+0x8/0x18

The sysfs unexport in pwmchip_remove() is completely asymmetric
to what we do in pwmchip_add_with_polarity() and commit 0733424c9ba9
("pwm: Unexport children before chip removal") is a strong indication
that this was wrong to begin with. We should just move
pwmchip_sysfs_unexport() where it belongs, which is right after
pwmchip_sysfs_unexport_children(). In that case, we do not need
separate functions anymore either.

We also really want to remove sysfs irrespective of whether or not
the chip will be removed as a result of pwmchip_remove(). We can only
assume that the driver will be gone after that, so we shouldn't leave
any dangling sysfs files around.

This warning disappears if we move pwmchip_sysfs_unexport() to
the top of pwmchip_remove(), pwmchip_sysfs_unexport_children().
That way it is also outside of the pwm_lock section, which indeed
doesn't seem to be needed.

Moving the pwmchip_sysfs_export() call outside of that section also
seems fine and it'd be perfectly symmetric with pwmchip_remove() again.

So, this patch fixes them.

Signed-off-by: Phong Hoang &lt;phong.hoang.wz@renesas.com&gt;
[shimoda: revise the commit log and code]
Fixes: 76abbdde2d95 ("pwm: Add sysfs interface")
Fixes: 0733424c9ba9 ("pwm: Unexport children before chip removal")
Signed-off-by: Yoshihiro Shimoda &lt;yoshihiro.shimoda.uh@renesas.com&gt;
Tested-by: Hoan Nguyen An &lt;na-hoan@jinso.co.jp&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Reviewed-by: Simon Horman &lt;horms+renesas@verge.net.au&gt;
Reviewed-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Signed-off-by: Thierry Reding &lt;thierry.reding@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
</entry>
</feed>
