linux-toradex.git/net/ieee802154/socket.c, branch v5.3.2 Linux kernel for Apalis and Colibri modules Merge branch 'ieee802154-for-davem-2019-08-24' of git://git.kernel.org/pub/scm/linux/kernel/git/sschmidt/wpan 2019-08-24T20:46:57+00:00 David S. Miller davem@davemloft.net 2019-08-24T20:46:57+00:00 12e2e15d837fd7d621d92fc81e3727304a2a2201 Stefan Schmidt says: ==================== pull-request: ieee802154 for net 2019-08-24 An update from ieee802154 for your *net* tree. Yue Haibing fixed two bugs discovered by KASAN in the hwsim driver for ieee802154 and Colin Ian King cleaned up a redundant variable assignment. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> 
Stefan Schmidt says:

====================
pull-request: ieee802154 for net 2019-08-24

An update from ieee802154 for your *net* tree.

Yue Haibing fixed two bugs discovered by KASAN in the hwsim driver for
ieee802154 and Colin Ian King cleaned up a redundant variable assignment.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
net: ieee802154: remove redundant assignment to rc 2019-08-13T23:10:41+00:00 Colin Ian King colin.king@canonical.com 2019-08-13T14:28:18+00:00 074014abdf2bd2a00da3dd14a6ae04cafc1d62cc Variable rc is initialized to a value that is never read and it is re-assigned later. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org> 
Variable rc is initialized to a value that is never read and it is
re-assigned later. The initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30T18:26:41+00:00 Thomas Gleixner tglx@linutronix.de 2019-05-27T06:55:21+00:00 1802d0beecafe581ad584634ba92f8a471d8a63a Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: rework SIOCGSTAMP ioctl handling 2019-04-19T21:07:40+00:00 Arnd Bergmann arnd@arndb.de 2019-04-17T20:51:48+00:00 c7cbdbf29f488a19982cd9f4a109887f18028bbb The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many socket protocol handlers, and all of those end up calling the same sock_get_timestamp()/sock_get_timestampns() helper functions, which results in a lot of duplicate code. With the introduction of 64-bit time_t on 32-bit architectures, this gets worse, as we then need four different ioctl commands in each socket protocol implementation. To simplify that, let's add a new .gettstamp() operation in struct proto_ops, and move ioctl implementation into the common sock_ioctl()/compat_sock_ioctl_trans() functions that these all go through. We can reuse the sock_get_timestamp() implementation, but generalize it so it can deal with both native and compat mode, as well as timeval and timespec structures. Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many
socket protocol handlers, and all of those end up calling the same
sock_get_timestamp()/sock_get_timestampns() helper functions, which
results in a lot of duplicate code.

With the introduction of 64-bit time_t on 32-bit architectures, this
gets worse, as we then need four different ioctl commands in each
socket protocol implementation.

To simplify that, let's add a new .gettstamp() operation in
struct proto_ops, and move ioctl implementation into the common
sock_ioctl()/compat_sock_ioctl_trans() functions that these all go
through.

We can reuse the sock_get_timestamp() implementation, but generalize
it so it can deal with both native and compat mode, as well as
timeval and timespec structures.

Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ieee802154: add rx LQI from userspace 2018-07-13T16:18:18+00:00 Romuald CARI romuald.cari@devialet.com 2018-06-07T14:08:02+00:00 811e299f4645588cc7a1b78d97b6847c155324b9 The Link Quality Indication data exposed by drivers could not be accessed from userspace. Since this data is per-datagram received, it makes sense to make it available to userspace application through the ancillary data mechanism in recvmsg rather than through ioctls. This can be activated using the socket option WPAN_WANTLQI under SOL_IEEE802154 protocol. This LQI data is available in the ancillary data buffer under the SOL_IEEE802154 level as the type WPAN_LQI. The value is an unsigned byte indicating the link quality with values ranging 0-255. Signed-off-by: Romuald Cari <romuald.cari@devialet.com> Signed-off-by: Clément Peron <clement.peron@devialet.com> Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org> 
The Link Quality Indication data exposed by drivers could not be accessed from
userspace. Since this data is per-datagram received, it makes sense to make it
available to userspace application through the ancillary data mechanism in
recvmsg rather than through ioctls. This can be activated using the socket
option WPAN_WANTLQI under SOL_IEEE802154 protocol.

This LQI data is available in the ancillary data buffer under the SOL_IEEE802154
level as the type WPAN_LQI. The value is an unsigned byte indicating the link
quality with values ranging 0-255.

Signed-off-by: Romuald Cari <romuald.cari@devialet.com>
Signed-off-by: Clément Peron <clement.peron@devialet.com>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28T17:40:47+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-06-28T16:43:44+00:00 a11e1d432b51f63ba698d044441284a661f01144 The poll() changes were not well thought out, and completely unexplained. They also caused a huge performance regression, because "->poll()" was no longer a trivial file operation that just called down to the underlying file operations, but instead did at least two indirect calls. Indirect calls are sadly slow now with the Spectre mitigation, but the performance problem could at least be largely mitigated by changing the "->get_poll_head()" operation to just have a per-file-descriptor pointer to the poll head instead. That gets rid of one of the new indirections. But that doesn't fix the new complexity that is completely unwarranted for the regular case. The (undocumented) reason for the poll() changes was some alleged AIO poll race fixing, but we don't make the common case slower and more complex for some uncommon special case, so this all really needs way more explanations and most likely a fundamental redesign. [ This revert is a revert of about 30 different commits, not reverted individually because that would just be unnecessarily messy - Linus ] Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
net: convert datagram_poll users tp ->poll_mask 2018-05-26T07:16:44+00:00 Christoph Hellwig hch@lst.de 2018-04-09T13:27:37+00:00 db5051ead64a987e863f71a770351a75be542b15 Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: ieee802154: fix net_device reference release too early 2017-05-23T18:05:15+00:00 Lin Zhang xiaolou4617@gmail.com 2017-05-23T05:29:39+00:00 a611c58b3d42a92e6b23423e166dd17c0c7fffce This patch fixes the kernel oops when release net_device reference in advance. In function raw_sendmsg(i think the dgram_sendmsg has the same problem), there is a race condition between dev_put and dev_queue_xmit when the device is gong that maybe lead to dev_queue_ximt to see an illegal net_device pointer. My test kernel is 3.13.0-32 and because i am not have a real 802154 device, so i change lowpan_newlink function to this: /* find and hold real wpan device */ real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK])); if (!real_dev) return -ENODEV; // if (real_dev->type != ARPHRD_IEEE802154) { // dev_put(real_dev); // return -EINVAL; // } lowpan_dev_info(dev)->real_dev = real_dev; lowpan_dev_info(dev)->fragment_tag = 0; mutex_init(&lowpan_dev_info(dev)->dev_list_mtx); Also, in order to simulate preempt, i change the raw_sendmsg function to this: skb->dev = dev; skb->sk = sk; skb->protocol = htons(ETH_P_IEEE802154); dev_put(dev); //simulate preempt schedule_timeout_uninterruptible(30 * HZ); err = dev_queue_xmit(skb); if (err > 0) err = net_xmit_errno(err); and this is my userspace test code named test_send_data: int main(int argc, char **argv) { char buf[127]; int sockfd; sockfd = socket(AF_IEEE802154, SOCK_RAW, 0); if (sockfd < 0) { printf("create sockfd error: %s\n", strerror(errno)); return -1; } send(sockfd, buf, sizeof(buf), 0); return 0; } This is my test case: root@zhanglin-x-computer:~/develop/802154# uname -a Linux zhanglin-x-computer 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux root@zhanglin-x-computer:~/develop/802154# ip link add link eth0 name lowpan0 type lowpan root@zhanglin-x-computer:~/develop/802154# //keep the lowpan0 device down root@zhanglin-x-computer:~/develop/802154# ./test_send_data & //wait a while root@zhanglin-x-computer:~/develop/802154# ip link del link dev lowpan0 //the device is gone //oops [381.303307] general protection fault: 0000 [#1]SMP [381.303407] Modules linked in: af_802154 6lowpan bnep rfcomm bluetooth nls_iso8859_1 snd_hda_codec_hdmi snd_hda_codec_realtek rts5139(C) snd_hda_intel snd_had_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi snd_seq_midi_event snd_rawmidi snd_req intel_rapl snd_seq_device coretemp i915 kvm_intel kvm snd_timer snd crct10dif_pclmul crc32_pclmul ghash_clmulni_intel cypted drm_kms_helper drm i2c_algo_bit soundcore video mac_hid parport_pc ppdev ip parport hid_generic usbhid hid ahci r8169 mii libahdi [381.304286] CPU:1 PID: 2524 Commm: 1 Tainted: G C 0 3.13.0-32-generic [381.304409] Hardware name: Haier Haier DT Computer/Haier DT Codputer, BIOS FIBT19H02_X64 06/09/2014 [381.304546] tasks: ffff000096965fc0 ti: ffffB0013779c000 task.ti: ffffB8013779c000 [381.304659] RIP: 0010:[<ffffffff01621fe1>] [<ffffffff81621fe1>] __dev_queue_ximt+0x61/0x500 [381.304798] RSP: 0018:ffffB8013779dca0 EFLAGS: 00010202 [381.304880] RAX: 272b031d57565351 RBX: 0000000000000000 RCX: ffff8800968f1a00 [381.304987] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800968f1a00 [381.305095] RBP: ffff8e013773dce0 R08: 0000000000000266 R09: 0000000000000004 [381.305202] R10: 0000000000000004 R11: 0000000000000005 R12: ffff88013902e000 [381.305310] R13: 000000000000007f R14: 000000000000007f R15: ffff8800968f1a00 [381.305418] FS: 00007fc57f50f740(0000) GS: ffff88013fc80000(0000) knlGS: 0000000000000000 [381.305540] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [381.305627] CR2: 00007fad0841c000 CR3: 00000001368dd000 CR4: 00000000001007e0 [361.905734] Stack: [381.305768] 00000000002052d0 000000003facb30a ffff88013779dcc0 ffff880137764000 [381.305898] ffff88013779de70 000000000000007f 000000000000007f ffff88013902e000 [381.306026] ffff88013779dcf0 ffffffff81622490 ffff88013779dd39 ffffffffa03af9f1 [381.306155] Call Trace: [381.306202] [<ffffffff81622490>] dev_queue_xmit+0x10/0x20 [381.306294] [<ffffffffa03af9f1>] raw_sendmsg+0x1b1/0x270 [af_802154] [381.306396] [<ffffffffa03af054>] ieee802154_sock_sendmsg+0x14/0x20 [af_802154] [381.306512] [<ffffffff816079eb>] sock_sendmsg+0x8b/0xc0 [381.306600] [<ffffffff811d52a5>] ? __d_alloc+0x25/0x180 [381.306687] [<ffffffff811a1f56>] ? kmem_cache_alloc_trace+0x1c6/0x1f0 [381.306791] [<ffffffff81607b91>] SYSC_sendto+0x121/0x1c0 [381.306878] [<ffffffff8109ddf4>] ? vtime_account_user+x54/0x60 [381.306975] [<ffffffff81020d45>] ? syscall_trace_enter+0x145/0x250 [381.307073] [<ffffffff816086ae>] SyS_sendto+0xe/0x10 [381.307156] [<ffffffff8172c87f>] tracesys+0xe1/0xe6 [381.307233] Code: c6 a1 a4 ff 41 8b 57 78 49 8b 47 20 85 d2 48 8b 80 78 07 00 00 75 21 49 8b 57 18 48 85 d2 74 18 48 85 c0 74 13 8b 92 ac 01 00 00 <3b> 50 10 73 08 8b 44 90 14 41 89 47 78 41 f6 84 24 d5 00 00 00 [381.307801] RIP [<ffffffff81621fe1>] _dev_queue_xmit+0x61/0x500 [381.307901] RSP <ffff88013779dca0> [381.347512] Kernel panic - not syncing: Fatal exception in interrupt [381.347747] drm_kms_helper: panic occurred, switching back to text console In my opinion, there is always exist a chance that the device is gong before call dev_queue_xmit. I think the latest kernel is have the same problem and that dev_put should be behind of the dev_queue_xmit. Signed-off-by: Lin Zhang <xiaolou4617@gmail.com> Acked-by: Stefan Schmidt <stefan@osg.samsung.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> 
This patch fixes the kernel oops when release net_device reference in
advance. In function raw_sendmsg(i think the dgram_sendmsg has the same
problem), there is a race condition between dev_put and dev_queue_xmit
when the device is gong that maybe lead to dev_queue_ximt to see
an illegal net_device pointer.

My test kernel is 3.13.0-32 and because i am not have a real 802154
device, so i change lowpan_newlink function to this:

        /* find and hold real wpan device */
        real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
        if (!real_dev)
                return -ENODEV;
//      if (real_dev->type != ARPHRD_IEEE802154) {
//              dev_put(real_dev);
//              return -EINVAL;
//      }
        lowpan_dev_info(dev)->real_dev = real_dev;
        lowpan_dev_info(dev)->fragment_tag = 0;
        mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);

Also, in order to simulate preempt, i change the raw_sendmsg function
to this:

        skb->dev = dev;
        skb->sk  = sk;
        skb->protocol = htons(ETH_P_IEEE802154);
        dev_put(dev);
        //simulate preempt
        schedule_timeout_uninterruptible(30 * HZ);
        err = dev_queue_xmit(skb);
        if (err > 0)
                err = net_xmit_errno(err);

and this is my userspace test code named test_send_data:

int main(int argc, char **argv)
{
        char buf[127];
        int sockfd;
        sockfd = socket(AF_IEEE802154, SOCK_RAW, 0);
        if (sockfd < 0) {
                printf("create sockfd error: %s\n", strerror(errno));
                return -1;
        }
        send(sockfd, buf, sizeof(buf), 0);
        return 0;
}

This is my test case:

root@zhanglin-x-computer:~/develop/802154# uname -a
Linux zhanglin-x-computer 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15
03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
root@zhanglin-x-computer:~/develop/802154# ip link add link eth0 name
lowpan0 type lowpan
root@zhanglin-x-computer:~/develop/802154#
//keep the lowpan0 device down
root@zhanglin-x-computer:~/develop/802154# ./test_send_data &
//wait a while
root@zhanglin-x-computer:~/develop/802154# ip link del link dev lowpan0
//the device is gone
//oops
[381.303307] general protection fault: 0000 [#1]SMP
[381.303407] Modules linked in: af_802154 6lowpan bnep rfcomm
bluetooth nls_iso8859_1 snd_hda_codec_hdmi snd_hda_codec_realtek
rts5139(C) snd_hda_intel
snd_had_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi
snd_seq_midi_event snd_rawmidi snd_req intel_rapl snd_seq_device
coretemp i915 kvm_intel
kvm snd_timer snd crct10dif_pclmul crc32_pclmul ghash_clmulni_intel
cypted drm_kms_helper drm i2c_algo_bit soundcore video mac_hid
parport_pc ppdev ip parport hid_generic
usbhid hid ahci r8169 mii libahdi
[381.304286] CPU:1 PID: 2524 Commm: 1 Tainted: G C 0 3.13.0-32-generic
[381.304409] Hardware name: Haier Haier DT Computer/Haier DT Codputer,
BIOS FIBT19H02_X64 06/09/2014
[381.304546] tasks: ffff000096965fc0 ti: ffffB0013779c000 task.ti:
ffffB8013779c000
[381.304659] RIP: 0010:[<ffffffff01621fe1>] [<ffffffff81621fe1>]
__dev_queue_ximt+0x61/0x500
[381.304798] RSP: 0018:ffffB8013779dca0 EFLAGS: 00010202
[381.304880] RAX: 272b031d57565351 RBX: 0000000000000000 RCX: ffff8800968f1a00
[381.304987] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800968f1a00
[381.305095] RBP: ffff8e013773dce0 R08: 0000000000000266 R09: 0000000000000004
[381.305202] R10: 0000000000000004 R11: 0000000000000005 R12: ffff88013902e000
[381.305310] R13: 000000000000007f R14: 000000000000007f R15: ffff8800968f1a00
[381.305418] FS:  00007fc57f50f740(0000) GS: ffff88013fc80000(0000)
knlGS: 0000000000000000
[381.305540] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[381.305627] CR2: 00007fad0841c000 CR3: 00000001368dd000 CR4: 00000000001007e0
[361.905734] Stack:
[381.305768]  00000000002052d0 000000003facb30a ffff88013779dcc0
ffff880137764000
[381.305898]  ffff88013779de70 000000000000007f 000000000000007f
ffff88013902e000
[381.306026]  ffff88013779dcf0 ffffffff81622490 ffff88013779dd39
ffffffffa03af9f1
[381.306155] Call Trace:
[381.306202]  [<ffffffff81622490>] dev_queue_xmit+0x10/0x20
[381.306294]  [<ffffffffa03af9f1>] raw_sendmsg+0x1b1/0x270 [af_802154]
[381.306396]  [<ffffffffa03af054>] ieee802154_sock_sendmsg+0x14/0x20 [af_802154]
[381.306512]  [<ffffffff816079eb>] sock_sendmsg+0x8b/0xc0
[381.306600]  [<ffffffff811d52a5>] ? __d_alloc+0x25/0x180
[381.306687]  [<ffffffff811a1f56>] ? kmem_cache_alloc_trace+0x1c6/0x1f0
[381.306791]  [<ffffffff81607b91>] SYSC_sendto+0x121/0x1c0
[381.306878]  [<ffffffff8109ddf4>] ? vtime_account_user+x54/0x60
[381.306975]  [<ffffffff81020d45>] ? syscall_trace_enter+0x145/0x250
[381.307073]  [<ffffffff816086ae>] SyS_sendto+0xe/0x10
[381.307156]  [<ffffffff8172c87f>] tracesys+0xe1/0xe6
[381.307233] Code: c6 a1 a4 ff 41 8b 57 78 49 8b 47 20 85 d2 48 8b 80
78 07 00 00 75 21 49 8b 57 18 48 85 d2 74 18 48 85 c0 74 13 8b 92 ac
01 00 00 <3b> 50 10 73 08 8b 44 90 14 41 89 47 78 41 f6 84 24 d5 00 00
00
[381.307801] RIP [<ffffffff81621fe1>] _dev_queue_xmit+0x61/0x500
[381.307901]  RSP <ffff88013779dca0>
[381.347512] Kernel panic - not syncing: Fatal exception in interrupt
[381.347747] drm_kms_helper: panic occurred, switching back to text console

In my opinion, there is always exist a chance that the device is gong
before call dev_queue_xmit.

I think the latest kernel is have the same problem and that
dev_put should be behind of the dev_queue_xmit.

Signed-off-by: Lin Zhang <xiaolou4617@gmail.com>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
net: ieee802154: remove explicit set skb->sk 2017-05-23T18:05:15+00:00 Lin Zhang xiaolou4617@gmail.com 2017-05-23T05:21:05+00:00 8fafda77762df659e578e349c4a67196d94957dc Explicit set skb->sk is needless, sock_alloc_send_skb is already set it. Signed-off-by: Lin Zhang <xiaolou4617@gmail.com> Acked-by: Stefan Schmidt <stefan@osg.samsung.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> 
Explicit set skb->sk is needless, sock_alloc_send_skb is already set it.

Signed-off-by: Lin Zhang <xiaolou4617@gmail.com>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
lib/vsprintf.c: remove %Z support 2017-02-28T02:43:47+00:00 Alexey Dobriyan adobriyan@gmail.com 2017-02-27T22:30:02+00:00 5b5e0928f742cfa853b2411400a1b19fa379d758 Now that %z is standartised in C99 there is no reason to support %Z. Unlike %L it doesn't even make format strings smaller. Use BUILD_BUG_ON in a couple ATM drivers. In case anyone didn't notice lib/vsprintf.o is about half of SLUB which is in my opinion is quite an achievement. Hopefully this patch inspires someone else to trim vsprintf.c more. Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>