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Marc Zyngier c8101f7729 net: dsa: Fix lockdep false positive splat
Creating a macvtap on a DSA-backed interface results in the following
splat when lockdep is enabled:

[   19.638080] IPv6: ADDRCONF(NETDEV_CHANGE): lan0: link becomes ready
[   23.041198] device lan0 entered promiscuous mode
[   23.043445] device eth0 entered promiscuous mode
[   23.049255]
[   23.049557] ============================================
[   23.055021] WARNING: possible recursive locking detected
[   23.060490] 5.0.0-rc3-00013-g56c857a1b8d3 #118 Not tainted
[   23.066132] --------------------------------------------
[   23.071598] ip/2861 is trying to acquire lock:
[   23.076171] 00000000f61990cb (_xmit_ETHER){+...}, at: dev_set_rx_mode+0x1c/0x38
[   23.083693]
[   23.083693] but task is already holding lock:
[   23.089696] 00000000ecf0c3b4 (_xmit_ETHER){+...}, at: dev_uc_add+0x24/0x70
[   23.096774]
[   23.096774] other info that might help us debug this:
[   23.103494]  Possible unsafe locking scenario:
[   23.103494]
[   23.109584]        CPU0
[   23.112093]        ----
[   23.114601]   lock(_xmit_ETHER);
[   23.117917]   lock(_xmit_ETHER);
[   23.121233]
[   23.121233]  *** DEADLOCK ***
[   23.121233]
[   23.127325]  May be due to missing lock nesting notation
[   23.127325]
[   23.134315] 2 locks held by ip/2861:
[   23.137987]  #0: 000000003b766c72 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x338/0x4e0
[   23.146231]  #1: 00000000ecf0c3b4 (_xmit_ETHER){+...}, at: dev_uc_add+0x24/0x70
[   23.153757]
[   23.153757] stack backtrace:
[   23.158243] CPU: 0 PID: 2861 Comm: ip Not tainted 5.0.0-rc3-00013-g56c857a1b8d3 #118
[   23.166212] Hardware name: Globalscale Marvell ESPRESSOBin Board (DT)
[   23.172843] Call trace:
[   23.175358]  dump_backtrace+0x0/0x188
[   23.179116]  show_stack+0x14/0x20
[   23.182524]  dump_stack+0xb4/0xec
[   23.185928]  __lock_acquire+0x123c/0x1860
[   23.190048]  lock_acquire+0xc8/0x248
[   23.193724]  _raw_spin_lock_bh+0x40/0x58
[   23.197755]  dev_set_rx_mode+0x1c/0x38
[   23.201607]  dev_set_promiscuity+0x3c/0x50
[   23.205820]  dsa_slave_change_rx_flags+0x5c/0x70
[   23.210567]  __dev_set_promiscuity+0x148/0x1e0
[   23.215136]  __dev_set_rx_mode+0x74/0x98
[   23.219167]  dev_uc_add+0x54/0x70
[   23.222575]  macvlan_open+0x170/0x1d0
[   23.226336]  __dev_open+0xe0/0x160
[   23.229830]  __dev_change_flags+0x16c/0x1b8
[   23.234132]  dev_change_flags+0x20/0x60
[   23.238074]  do_setlink+0x2d0/0xc50
[   23.241658]  __rtnl_newlink+0x5f8/0x6e8
[   23.245601]  rtnl_newlink+0x50/0x78
[   23.249184]  rtnetlink_rcv_msg+0x360/0x4e0
[   23.253397]  netlink_rcv_skb+0xe8/0x130
[   23.257338]  rtnetlink_rcv+0x14/0x20
[   23.261012]  netlink_unicast+0x190/0x210
[   23.265043]  netlink_sendmsg+0x288/0x350
[   23.269075]  sock_sendmsg+0x18/0x30
[   23.272659]  ___sys_sendmsg+0x29c/0x2c8
[   23.276602]  __sys_sendmsg+0x60/0xb8
[   23.280276]  __arm64_sys_sendmsg+0x1c/0x28
[   23.284488]  el0_svc_common+0xd8/0x138
[   23.288340]  el0_svc_handler+0x24/0x80
[   23.292192]  el0_svc+0x8/0xc

This looks fairly harmless (no actual deadlock occurs), and is
fixed in a similar way to c6894dec8e ("bridge: fix lockdep
addr_list_lock false positive splat") by putting the addr_list_lock
in its own lockdep class.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-04 18:30:43 -08:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-01-27 12:02:00 -08:00
block Revert "block: cover another queue enter recursion via BIO_QUEUE_ENTERED" 2019-01-27 06:35:28 -07:00
certs kbuild: remove redundant target cleaning on failure 2019-01-06 09:46:51 +09:00
crypto crypto: sm3 - fix undefined shift by >= width of value 2019-01-10 21:37:32 +08:00
Documentation drm fixes. msm, sun4i, amdgpu, i915 gvt 2019-01-25 12:19:10 +13:00
drivers s390/qeth: conclude all event processing before offlining a card 2019-02-04 09:43:48 -08:00
firmware kbuild: change filechk to surround the given command with { } 2019-01-06 09:46:51 +09:00
fs a set of small smb3 fixes, some fixing various crediting issues discovered during xfstest runs, five for stable 2019-01-26 15:38:22 -08:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-02-01 15:28:07 -08:00
init kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7 2019-01-14 10:37:09 +09:00
ipc ipc: IPCMNI limit check for semmni 2018-10-31 08:54:14 -07:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-02-01 15:28:07 -08:00
lib lib/test_rhashtable: Make test_insert_dup() allocate its hash table dynamically 2019-01-31 09:36:52 -08:00
LICENSES This is a fairly typical cycle for documentation. There's some welcome 2018-10-24 18:01:11 +01:00
mm Revert "mm, memory_hotplug: initialize struct pages for the full memory section" 2019-01-28 10:35:22 -08:00
net net: dsa: Fix lockdep false positive splat 2019-02-04 18:30:43 -08:00
samples samples/bpf: workaround clang asm goto compilation errors 2019-01-15 20:57:30 +01:00
scripts Bug fixes for gcc-plugins 2019-01-21 13:07:03 +13:00
security Merge branch 'fixes-v5.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-01-17 16:54:58 +12:00
sound sound fixes for 5.0-rc4 2019-01-25 05:55:26 +13:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-02-01 15:28:07 -08:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt KVM: validate userspace input in kvm_clear_dirty_log_protect() 2019-01-11 18:38:07 +01:00
.clang-format clang-format: Update .clang-format with the latest for_each macro list 2019-01-19 19:26:06 +01:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support for DT binding schema checks 2018-12-13 09:41:32 -06:00
.mailmap A few early MIPS fixes for 4.21: 2019-01-05 12:48:25 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Add CREDITS entry for Shaohua Li 2019-01-04 14:27:09 -07:00
Kbuild kbuild: use assignment instead of define ... endef for filechk_* rules 2019-01-06 10:22:35 +09:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS wireless-drivers fixes for 5.0 2019-02-04 09:12:06 -08:00
Makefile Linux 5.0-rc4 2019-01-27 15:18:05 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

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.