Since tun->flags might be shared by multiple tfile structures,
it is better to make sure tun_get_user() is using the flags
for the current tfile.

Presence of the READ_ONCE() in tun_napi_frags_enabled() gave a hint
of what could happen, but we need something stronger to please
syzbot.

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 13647 Comm: syz-executor5 Not tainted 4.19.0-rc5+ torvalds#59
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:dev_gro_receive+0x132/0x2720 net/core/dev.c:5427
Code: 48 c1 ea 03 80 3c 02 00 0f 85 6e 20 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 6e 10 49 8d bd d0 00 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 59 20 00 00 4d 8b a5 d0 00 00 00 31 ff 41 81 e4
RSP: 0018:ffff8801c400f410 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8618d325
RDX: 000000000000001a RSI: ffffffff86189f97 RDI: 00000000000000d0
RBP: ffff8801c400f608 R08: ffff8801c8fb4300 R09: 0000000000000000
R10: ffffed0038801ed7 R11: 0000000000000003 R12: ffff8801d327d358
R13: 0000000000000000 R14: ffff8801c16dd8c0 R15: 0000000000000004
FS:  00007fe003615700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe1f3c43db8 CR3: 00000001bebb2000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 napi_gro_frags+0x3f4/0xc90 net/core/dev.c:5715
 tun_get_user+0x31d5/0x42a0 drivers/net/tun.c:1922
 tun_chr_write_iter+0xb9/0x154 drivers/net/tun.c:1967
 call_write_iter include/linux/fs.h:1808 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x6b8/0x9f0 fs/read_write.c:487
 vfs_write+0x1fc/0x560 fs/read_write.c:549
 ksys_write+0x101/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 <48> 3d 01 f0 ff ff 0f 83 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe003614c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000012 RSI: 0000000020000000 RDI: 000000000000000a
RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe0036156d4
R13: 00000000004c5574 R14: 00000000004d8e98 R15: 00000000ffffffff
Modules linked in:

RIP: 0010:dev_gro_receive+0x132/0x2720 net/core/dev.c:5427
Code: 48 c1 ea 03 80 3c 02 00 0f 85 6e 20 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 6e 10 49 8d bd d0 00 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 59 20 00 00 4d 8b a5 d0 00 00 00 31 ff 41 81 e4
RSP: 0018:ffff8801c400f410 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8618d325
RDX: 000000000000001a RSI: ffffffff86189f97 RDI: 00000000000000d0
RBP: ffff8801c400f608 R08: ffff8801c8fb4300 R09: 0000000000000000
R10: ffffed0038801ed7 R11: 0000000000000003 R12: ffff8801d327d358
R13: 0000000000000000 R14: ffff8801c16dd8c0 R15: 0000000000000004
FS:  00007fe003615700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe1f3c43db8 CR3: 00000001bebb2000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 90e33d4 ("tun: enable napi_gro_frags() for TUN/TAP driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sergey Suloev reported a crash happening in drm_client_dev_hotplug()
when fbdev had failed to register.

[    9.124598] vc4_hdmi 3f902000.hdmi: ASoC: Failed to create component debugfs directory
[    9.147667] vc4_hdmi 3f902000.hdmi: vc4-hdmi-hifi <-> 3f902000.hdmi mapping ok
[    9.155184] vc4_hdmi 3f902000.hdmi: ASoC: no DMI vendor name!
[    9.166544] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
[    9.173840] vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops [vc4])
[    9.181029] vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4])
[    9.188519] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
[    9.195690] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4])
[    9.203523] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4])
[    9.215032] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4])
[    9.274785] vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
[    9.290246] [drm] Initialized vc4 0.0.0 20140616 for soc:gpu on minor 0
[    9.297464] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    9.304600] [drm] Driver supports precise vblank timestamp query.
[    9.382856] vc4-drm soc:gpu: [drm:drm_fb_helper_fbdev_setup [drm_kms_helper]] *ERROR* Failed to set fbdev configuration
[   10.404937] Unable to handle kernel paging request at virtual address 00330a656369768a
[   10.441620] [00330a656369768a] address between user and kernel address ranges
[   10.449087] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[   10.454762] Modules linked in: brcmfmac vc4 drm_kms_helper cfg80211 drm rfkill smsc95xx brcmutil usbnet drm_panel_orientation_quirks raspberrypi_hwmon bcm2835_dma crc32_ce pwm_bcm2835 bcm2835_rng virt_dma rng_core i2c_bcm2835 ip_tables x_tables ipv6
[   10.477296] CPU: 2 PID: 45 Comm: kworker/2:1 Not tainted 4.19.0-rc5 #3
[   10.483934] Hardware name: Raspberry Pi 3 Model B Rev 1.2 (DT)
[   10.489966] Workqueue: events output_poll_execute [drm_kms_helper]
[   10.596515] Process kworker/2:1 (pid: 45, stack limit = 0x000000007e8924dc)
[   10.603590] Call trace:
[   10.606259]  drm_client_dev_hotplug+0x5c/0xb0 [drm]
[   10.611303]  drm_kms_helper_hotplug_event+0x30/0x40 [drm_kms_helper]
[   10.617849]  output_poll_execute+0xc4/0x1e0 [drm_kms_helper]
[   10.623616]  process_one_work+0x1c8/0x318
[   10.627695]  worker_thread+0x48/0x428
[   10.631420]  kthread+0xf8/0x128
[   10.634615]  ret_from_fork+0x10/0x18
[   10.638255] Code: 54000220 f9401261 aa1303e0 b4000141 (f9400c2)
[   10.644456] ---[ end trace c75b4a4b0e141908 ]---

The reason for this is that drm_fbdev_cma_init() removes the drm_client
when fbdev registration fails, but it doesn't remove the client from the
drm_device client list. So the client list now has a pointer that points
into the unknown and we have a 'use after free' situation.

Split drm_client_new() into drm_client_init() and drm_client_add() to fix
removal in the error path.

Fixes: 894a677 ("drm/cma-helper: Use the generic fbdev emulation")
Reported-by: Sergey Suloev <ssuloev@orpaltech.com>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181001194536.57756-1-noralf@tronnes.org

This reverts commit d76c743.

While commit d76c743 ("serial: 8250_dw: Fix runtime PM handling")
fixes runtime PM handling when using kgdb, it introduces a traceback for
everyone else.

BUG: sleeping function called from invalid context at
	/mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034
in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0
7 locks held by swapper/0/1:
 #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b
 #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b
 #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb
 #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0
 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0
 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217
 torvalds#6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f
irq event stamp: 735222
__down_trylock_console_sem+0x4a/0x84
console_unlock+0x338/0x60f
__do_softirq+0x4a4/0x50d
irq_exit+0x64/0xe2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 torvalds#6
Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017
Call Trace:
 dump_stack+0x7d/0xbd
 ___might_sleep+0x238/0x259
 __pm_runtime_resume+0x4e/0xa4
 ? serial8250_rpm_get+0x2e/0x44
 serial8250_console_write+0x44/0x301
 ? lock_acquire+0x1b8/0x1fa
 console_unlock+0x577/0x60f
 vprintk_emit+0x1f0/0x217
 printk+0x52/0x6e
 register_console+0x43b/0x524
 uart_add_one_port+0x672/0x8b0
 ? set_io_from_upio+0x150/0x162
 serial8250_register_8250_port+0x825/0x8bb
 dw8250_probe+0x80c/0x8b0
 ? dw8250_serial_inq+0x8e/0x8e
 ? dw8250_check_lcr+0x108/0x108
 ? dw8250_runtime_resume+0x5b/0x5b
 ? dw8250_serial_outq+0xa1/0xa1
 ? dw8250_remove+0x115/0x115
 platform_drv_probe+0x76/0xc5
 really_probe+0x1f1/0x3ee
 ? driver_allows_async_probing+0x5d/0x5d
 driver_probe_device+0xd6/0x112
 ? driver_allows_async_probing+0x5d/0x5d
 bus_for_each_drv+0xbe/0xe5
 __device_attach+0xdd/0x15b
 bus_probe_device+0x5a/0x10b
 device_add+0x501/0x894
 ? _raw_write_unlock+0x27/0x3a
 platform_device_add+0x224/0x2b7
 mfd_add_device+0x718/0x75b
 ? __kmalloc+0x144/0x16a
 ? mfd_add_devices+0x38/0xdb
 mfd_add_devices+0x9b/0xdb
 intel_lpss_probe+0x7d4/0x8ee
 intel_lpss_pci_probe+0xac/0xd4
 pci_device_probe+0x101/0x18e
...

Revert the offending patch until a more comprehensive solution
is available.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Fixes: d76c743 ("serial: 8250_dw: Fix runtime PM handling")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The incoming skb needs to be reallocated in case the headroom
is not sufficient to add the MAP header. This allocation needs to
be atomic otherwise it results in the following splat

[32805.801456] BUG: sleeping function called from invalid context
[32805.841141] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[32805.904773] task: ffffffd7c5f62280 task.stack: ffffff80464a8000
[32805.910851] pc : ___might_sleep+0x180/0x188
[32805.915143] lr : ___might_sleep+0x180/0x188
[32806.131520] Call trace:
[32806.134041]  ___might_sleep+0x180/0x188
[32806.137980]  __might_sleep+0x50/0x84
[32806.141653]  __kmalloc_track_caller+0x80/0x3bc
[32806.146215]  __kmalloc_reserve+0x3c/0x88
[32806.150241]  pskb_expand_head+0x74/0x288
[32806.154269]  rmnet_egress_handler+0xb0/0x1d8
[32806.162239]  rmnet_vnd_start_xmit+0xc8/0x13c
[32806.166627]  dev_hard_start_xmit+0x148/0x280
[32806.181181]  sch_direct_xmit+0xa4/0x198
[32806.185125]  __qdisc_run+0x1f8/0x310
[32806.188803]  net_tx_action+0x23c/0x26c
[32806.192655]  __do_softirq+0x220/0x408
[32806.196420]  do_softirq+0x4c/0x70

Fixes: ceed73a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

team's ndo_add_slave() acquires 'team->lock' and later tries to open the
newly enslaved device via dev_open(). This emits a 'NETDEV_UP' event
that causes the VLAN driver to add VLAN 0 on the team device. team's
ndo_vlan_rx_add_vid() will also try to acquire 'team->lock' and
deadlock.

Fix this by checking early at the enslavement function that a team
device is not being enslaved to itself.

A similar check was added to the bond driver in commit 09a89c2
("bonding: disallow enslaving a bond to itself").

WARNING: possible recursive locking detected
4.18.0-rc7+ torvalds#176 Not tainted
--------------------------------------------
syz-executor4/6391 is trying to acquire lock:
(____ptrval____) (&team->lock){+.+.}, at: team_vlan_rx_add_vid+0x3b/0x1e0 drivers/net/team/team.c:1868

but task is already holding lock:
(____ptrval____) (&team->lock){+.+.}, at: team_add_slave+0xdb/0x1c30 drivers/net/team/team.c:1947

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&team->lock);
  lock(&team->lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz-executor4/6391:
 #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x412/0xc30 net/core/rtnetlink.c:4662
 #1: (____ptrval____) (&team->lock){+.+.}, at: team_add_slave+0xdb/0x1c30 drivers/net/team/team.c:1947

stack backtrace:
CPU: 1 PID: 6391 Comm: syz-executor4 Not tainted 4.18.0-rc7+ torvalds#176
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_deadlock_bug kernel/locking/lockdep.c:1765 [inline]
 check_deadlock kernel/locking/lockdep.c:1809 [inline]
 validate_chain kernel/locking/lockdep.c:2405 [inline]
 __lock_acquire.cold.64+0x1fb/0x486 kernel/locking/lockdep.c:3435
 lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924
 __mutex_lock_common kernel/locking/mutex.c:757 [inline]
 __mutex_lock+0x176/0x1820 kernel/locking/mutex.c:894
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909
 team_vlan_rx_add_vid+0x3b/0x1e0 drivers/net/team/team.c:1868
 vlan_add_rx_filter_info+0x14a/0x1d0 net/8021q/vlan_core.c:210
 __vlan_vid_add net/8021q/vlan_core.c:278 [inline]
 vlan_vid_add+0x63e/0x9d0 net/8021q/vlan_core.c:308
 vlan_device_event.cold.12+0x2a/0x2f net/8021q/vlan.c:381
 notifier_call_chain+0x180/0x390 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735
 call_netdevice_notifiers net/core/dev.c:1753 [inline]
 dev_open+0x173/0x1b0 net/core/dev.c:1433
 team_port_add drivers/net/team/team.c:1219 [inline]
 team_add_slave+0xa8b/0x1c30 drivers/net/team/team.c:1948
 do_set_master+0x1c9/0x220 net/core/rtnetlink.c:2248
 do_setlink+0xba4/0x3e10 net/core/rtnetlink.c:2382
 rtnl_setlink+0x2a9/0x400 net/core/rtnetlink.c:2636
 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4665
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2455
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4683
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0xa18/0xfd0 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:652
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2126
 __sys_sendmsg+0x11d/0x290 net/socket.c:2164
 __do_sys_sendmsg net/socket.c:2173 [inline]
 __se_sys_sendmsg net/socket.c:2171 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2171
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x456b29
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9706bf8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9706bf96d4 RCX: 0000000000456b29
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000004
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d3548 R14: 00000000004c8227 R15: 0000000000000000

Fixes: 87002b0 ("net: introduce vlan_vid_[add/del] and use them instead of direct [add/kill]_vid ndo calls")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-and-tested-by: syzbot+bd051aba086537515cdb@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>

With commit 2ea6263 ("powerpc/topology: Get topology for shared
processors at boot"), kdump kernel on shared LPAR may crash.

The necessary conditions are
- Shared LPAR with at least 2 nodes having memory and CPUs.
- Memory requirement for kdump kernel must be met by the first N-1
  nodes where there are at least N nodes with memory and CPUs.

Example numactl of such a machine.
  $ numactl -H
  available: 5 nodes (0,2,5-7)
  node 0 cpus:
  node 0 size: 0 MB
  node 0 free: 0 MB
  node 2 cpus:
  node 2 size: 255 MB
  node 2 free: 189 MB
  node 5 cpus: 24 25 26 27 28 29 30 31
  node 5 size: 4095 MB
  node 5 free: 4024 MB
  node 6 cpus: 0 1 2 3 4 5 6 7 16 17 18 19 20 21 22 23
  node 6 size: 6353 MB
  node 6 free: 5998 MB
  node 7 cpus: 8 9 10 11 12 13 14 15 32 33 34 35 36 37 38 39
  node 7 size: 7640 MB
  node 7 free: 7164 MB
  node distances:
  node   0   2   5   6   7
    0:  10  40  40  40  40
    2:  40  10  40  40  40
    5:  40  40  10  40  40
    6:  40  40  40  10  20
    7:  40  40  40  20  10

Steps to reproduce.
1. Load / start kdump service.
2. Trigger a kdump (for example : echo c > /proc/sysrq-trigger)

When booting a kdump kernel with 2048M:

  kexec: Starting switchover sequence.
  I'm in purgatory
  Using 1TB segments
  hash-mmu: Initializing hash mmu with SLB
  Linux version 4.19.0-rc5-master+ (srikar@linux-xxu6) (gcc version 4.8.5 (SUSE Linux)) #1 SMP Thu Sep 27 19:45:00 IST 2018
  Found initrd at 0xc000000009e70000:0xc00000000ae554b4
  Using pSeries machine description
  -----------------------------------------------------
  ppc64_pft_size    = 0x1e
  phys_mem_size     = 0x88000000
  dcache_bsize      = 0x80
  icache_bsize      = 0x80
  cpu_features      = 0x000000ff8f5d91a7
    possible        = 0x0000fbffcf5fb1a7
    always          = 0x0000006f8b5c91a1
  cpu_user_features = 0xdc0065c2 0xef000000
  mmu_features      = 0x7c006001
  firmware_features = 0x00000007c45bfc57
  htab_hash_mask    = 0x7fffff
  physical_start    = 0x8000000
  -----------------------------------------------------
  numa:   NODE_DATA [mem 0x87d5e300-0x87d67fff]
  numa:     NODE_DATA(0) on node 6
  numa:   NODE_DATA [mem 0x87d54600-0x87d5e2ff]
  Top of RAM: 0x88000000, Total RAM: 0x88000000
  Memory hole size: 0MB
  Zone ranges:
    DMA      [mem 0x0000000000000000-0x0000000087ffffff]
    DMA32    empty
    Normal   empty
  Movable zone start for each node
  Early memory node ranges
    node   6: [mem 0x0000000000000000-0x0000000087ffffff]
  Could not find start_pfn for node 0
  Initmem setup node 0 [mem 0x0000000000000000-0x0000000000000000]
  On node 0 totalpages: 0
  Initmem setup node 6 [mem 0x0000000000000000-0x0000000087ffffff]
  On node 6 totalpages: 34816

  Unable to handle kernel paging request for data at address 0x00000060
  Faulting instruction address: 0xc000000008703a54
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  CPU: 11 PID: 1 Comm: swapper/11 Not tainted 4.19.0-rc5-master+ #1
  NIP:  c000000008703a54 LR: c000000008703a38 CTR: 0000000000000000
  REGS: c00000000b673440 TRAP: 0380   Not tainted  (4.19.0-rc5-master+)
  MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 24022022  XER: 2000000
  CFAR: c0000000086fc238 IRQMASK: 0
  GPR00: c000000008703a38 c00000000b6736c0 c000000009281900 0000000000000000
  GPR04: 0000000000000000 0000000000000000 fffffffffffff001 c00000000b660080
  GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000220
  GPR12: 0000000000002200 c000000009e51400 0000000000000000 0000000000000008
  GPR16: 0000000000000000 c000000008c152e8 c000000008c152a8 0000000000000000
  GPR20: c000000009422fd8 c000000009412fd8 c000000009426040 0000000000000008
  GPR24: 0000000000000000 0000000000000000 c000000009168bc8 c000000009168c78
  GPR28: c00000000b126410 0000000000000000 c00000000916a0b8 c00000000b126400
  NIP [c000000008703a54] bus_add_device+0x84/0x1e0
  LR [c000000008703a38] bus_add_device+0x68/0x1e0
  Call Trace:
  [c00000000b6736c0] [c000000008703a38] bus_add_device+0x68/0x1e0 (unreliable)
  [c00000000b673740] [c000000008700194] device_add+0x454/0x7c0
  [c00000000b673800] [c00000000872e660] __register_one_node+0xb0/0x240
  [c00000000b673860] [c00000000839a6bc] __try_online_node+0x12c/0x180
  [c00000000b673900] [c00000000839b978] try_online_node+0x58/0x90
  [c00000000b673930] [c0000000080846d8] find_and_online_cpu_nid+0x158/0x190
  [c00000000b673a10] [c0000000080848a0] numa_update_cpu_topology+0x190/0x580
  [c00000000b673c00] [c000000008d3f2e4] smp_cpus_done+0x94/0x108
  [c00000000b673c70] [c000000008d5c00c] smp_init+0x174/0x19c
  [c00000000b673d00] [c000000008d346b8] kernel_init_freeable+0x1e0/0x450
  [c00000000b673dc0] [c0000000080102e8] kernel_init+0x28/0x160
  [c00000000b673e30] [c00000000800b65c] ret_from_kernel_thread+0x5c/0x80
  Instruction dump:
  60000000 60000000 e89e0020 7fe3fb78 4bff87d5 60000000 7c7d1b79 4082008c
  e8bf0050 e93e0098 3b9f0010 2fa50000 <e8690060> 38630018 419e0114 7f84e37
  ---[ end trace 593577668c2daa65 ]---

However a regular kernel with 4096M (2048 gets reserved for crash
kernel) boots properly.

Unlike regular kernels, which mark all available nodes as online,
kdump kernel only marks just enough nodes as online and marks the rest
as offline at boot. However kdump kernel boots with all available
CPUs. With Commit 2ea6263 ("powerpc/topology: Get topology for
shared processors at boot"), all CPUs are onlined on their respective
nodes at boot time. try_online_node() tries to online the offline
nodes but fails as all needed subsystems are not yet initialized.

As part of fix, detect and skip early onlining of a offline node.

Fixes: 2ea6263 ("powerpc/topology: Get topology for shared processors at boot")
Reported-by: Pavithra Prakash <pavrampu@in.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:

BUG: Bad page map in process JobWrk0013  pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma:          (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage:          (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G        W          4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
 dump_stack+0x5a/0x75
 print_bad_pte+0x217/0x2c0
 ? enqueue_task_fair+0x76/0x9f0
 _vm_normal_page+0xe5/0x100
 zap_pte_range+0x148/0x740
 unmap_page_range+0x39a/0x4b0
 unmap_vmas+0x42/0x90
 unmap_region+0x99/0xf0
 ? vma_gap_callbacks_rotate+0x1a/0x20
 do_munmap+0x255/0x3a0
 vm_munmap+0x54/0x80
 SyS_munmap+0x1d/0x30
 do_syscall_64+0x74/0x150
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...

when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.

Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).

Fixes: 69660fd ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd3119 ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

On systems with OF_IMAP_OLDWORLD_MAC set in of_irq_workarounds, the
devicetree interrupt parsing code is different, causing unit tests of
devicetree interrupt nodes to fail. Due to a bug in unittest code, which
tries to dereference an uninitialized pointer, this results in a crash.

OF: /testcase-data/phandle-tests/consumer-a: arguments longer than property
Unable to handle kernel paging request for data at address 0x00bc616e
Faulting instruction address: 0xc08e9468
Oops: Kernel access of bad area, sig: 11 [#1]
BE PREEMPT PowerMac
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.72-rc1-yocto-standard+ #1
task: cf8e0000 task.stack: cf8da000
NIP:  c08e9468 LR: c08ea5bc CTR: c08ea5a
REGS: cf8dbb50 TRAP: 0300   Not tainted  (4.14.72-rc1-yocto-standard+)
MSR:  00001032 <ME,IR,DR,RI>  CR: 82004044  XER: 00000000
DAR: 00bc616e DSISR: 40000000
GPR00: c08ea5bc cf8dbc00 cf8e0000 c13ca51 c13ca51 c13ca8a0 00000066 00000002
GPR08: 00000063 00bc614e c0b05865 000affff 82004048 00000000 c00047f0 00000000
GPR16: c0a80000 c0a9cc34 c13ca51 c0ad113 05ffffff 000affff c0b05860 c0abeef8
GPR24: cecec278 cecec278 c0a8c4d0 c0a885e0 c13ca8a0 05ffffff c13ca8a0 c13ca51

NIP [c08e9468] device_node_gen_full_name+0x30/0x15c
LR [c08ea5bc] device_node_string+0x190/0x3c8
Call Trace:
[cf8dbc00] [c007f670] trace_hardirqs_on_caller+0x118/0x1fc (unreliable)
[cf8dbc40] [c08ea5bc] device_node_string+0x190/0x3c8
[cf8dbcb0] [c08eb794] pointer+0x25c/0x4d0
[cf8dbd00] [c08ebcbc] vsnprintf+0x2b4/0x5ec
[cf8dbd60] [c08ec00c] vscnprintf+0x18/0x48
[cf8dbd70] [c008e268] vprintk_store+0x4c/0x22c
[cf8dbda0] [c008ecac] vprintk_emit+0x94/0x130
[cf8dbdd0] [c008ff54] printk+0x5c/0x6c
[cf8dbe10] [c0b8ddd4] of_unittest+0x2220/0x26f8
[cf8dbea0] [c0004434] do_one_initcall+0x4c/0x184
[cf8dbf00] [c0b4534c] kernel_init_freeable+0x13c/0x1d8
[cf8dbf30] [c0004814] kernel_init+0x24/0x118
[cf8dbf40] [c0013398] ret_from_kernel_thread+0x5c/0x64

The problem was observed when running a qemu test for the g3beige machine
with devicetree unittests enabled.

Disable interrupt node tests on affected systems to avoid both false
unittest failures and the crash.

With this patch in place, unittest on the affected system passes with
the following message.

	dt-test ### end of unittest - 144 passed, 0 failed

Fixes: 53a4209 ("of: Add device tree selftests")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>

syzbot managed to crash in skb_checksum_help() [1] :

        BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));

Root cause is the following check in skb_partial_csum_set()

	if (unlikely(start > skb_headlen(skb)) ||
	    unlikely((int)start + off > skb_headlen(skb) - 2))
		return false;

If skb_headlen(skb) is 1, then (skb_headlen(skb) - 2) becomes 0xffffffff
and the check fails to detect that ((int)start + off) is off the limit,
since the compare is unsigned.

When we fix that, then the first condition (start > skb_headlen(skb))
becomes obsolete.

Then we should also check that (skb_headroom(skb) + start) wont
overflow 16bit field.

[1]
kernel BUG at net/core/dev.c:2880!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 7330 Comm: syz-executor4 Not tainted 4.19.0-rc6+ torvalds#253
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:skb_checksum_help+0x9e3/0xbb0 net/core/dev.c:2880
Code: 85 00 ff ff ff 48 c1 e8 03 42 80 3c 28 00 0f 84 09 fb ff ff 48 8b bd 00 ff ff ff e8 97 a8 b9 fb e9 f8 fa ff ff e8 2d 09 76 fb <0f> 0b 48 8b bd 28 ff ff ff e8 1f a8 b9 fb e9 b1 f6 ff ff 48 89 cf
RSP: 0018:ffff8801d83a6f60 EFLAGS: 00010293
RAX: ffff8801b9834380 RBX: ffff8801b9f8d8c0 RCX: ffffffff8608c6d7
RDX: 0000000000000000 RSI: ffffffff8608cc63 RDI: 0000000000000006
RBP: ffff8801d83a7068 R08: ffff8801b9834380 R09: 0000000000000000
R10: ffff8801d83a76d8 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000010001 R14: 000000000000ffff R15: 00000000000000a8
FS:  00007f1a66db5700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7d77f091b0 CR3: 00000001ba252000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 skb_csum_hwoffload_help+0x8f/0xe0 net/core/dev.c:3269
 validate_xmit_skb+0xa2a/0xf30 net/core/dev.c:3312
 __dev_queue_xmit+0xc2f/0x3950 net/core/dev.c:3797
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3838
 packet_snd net/packet/af_packet.c:2928 [inline]
 packet_sendmsg+0x422d/0x64c0 net/packet/af_packet.c:2953

Fixes: 5ff8dda ("net: Ensure partial checksum offset is inside the skb head")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When booting kernel with LOCKDEP option, below warning info was found:

WARNING: possible recursive locking detected
4.19.0-rc7+ torvalds#14 Not tainted
--------------------------------------------
swapper/0/1 is trying to acquire lock:
00000000dcfc0fc8 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh
include/linux/spinlock.h:334 [inline]
00000000dcfc0fc8 (&(&list->lock)->rlock#4){+...}, at:
tipc_link_reset+0x125/0xdf0 net/tipc/link.c:850

but task is already holding lock:
00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh
include/linux/spinlock.h:334 [inline]
00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at:
tipc_link_reset+0xfa/0xdf0 net/tipc/link.c:849

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&list->lock)->rlock#4);
  lock(&(&list->lock)->rlock#4);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by swapper/0/1:
 #0: 00000000f7539d34 (pernet_ops_rwsem){+.+.}, at:
register_pernet_subsys+0x19/0x40 net/core/net_namespace.c:1051
 #1: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at:
spin_lock_bh include/linux/spinlock.h:334 [inline]
 #1: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at:
tipc_link_reset+0xfa/0xdf0 net/tipc/link.c:849

stack backtrace:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7+ torvalds#14
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1af/0x295 lib/dump_stack.c:113
 print_deadlock_bug kernel/locking/lockdep.c:1759 [inline]
 check_deadlock kernel/locking/lockdep.c:1803 [inline]
 validate_chain kernel/locking/lockdep.c:2399 [inline]
 __lock_acquire+0xf1e/0x3c60 kernel/locking/lockdep.c:3411
 lock_acquire+0x1db/0x520 kernel/locking/lockdep.c:3900
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168
 spin_lock_bh include/linux/spinlock.h:334 [inline]
 tipc_link_reset+0x125/0xdf0 net/tipc/link.c:850
 tipc_link_bc_create+0xb5/0x1f0 net/tipc/link.c:526
 tipc_bcast_init+0x59b/0xab0 net/tipc/bcast.c:521
 tipc_init_net+0x472/0x610 net/tipc/core.c:82
 ops_init+0xf7/0x520 net/core/net_namespace.c:129
 __register_pernet_operations net/core/net_namespace.c:940 [inline]
 register_pernet_operations+0x453/0xac0 net/core/net_namespace.c:1011
 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1052
 tipc_init+0x83/0x104 net/tipc/core.c:140
 do_one_initcall+0x109/0x70a init/main.c:885
 do_initcall_level init/main.c:953 [inline]
 do_initcalls init/main.c:961 [inline]
 do_basic_setup init/main.c:979 [inline]
 kernel_init_freeable+0x4bd/0x57f init/main.c:1144
 kernel_init+0x13/0x180 init/main.c:1063
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413

The reason why the noise above was complained by LOCKDEP is because we
nested to hold l->wakeupq.lock and l->inputq->lock in tipc_link_reset
function. In fact it's unnecessary to move skb buffer from l->wakeupq
queue to l->inputq queue while holding the two locks at the same time.
Instead, we can move skb buffers in l->wakeupq queue to a temporary
list first and then move the buffers of the temporary list to l->inputq
queue, which is also safe for us.

Fixes: 3f32d0b ("tipc: lock wakeup & inputq at tipc_link_reset()")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>

Signed-off-by: David S. Miller <davem@davemloft.net>

libdwfl parses an ELF file itself and creates mappings for the
individual sections. perf on the other hand sees raw mmap events which
represent individual sections. When we encounter an address pointing
into a mapping with pgoff != 0, we must take that into account and
report the file at the non-offset base address.

This fixes unwinding with libdwfl in some cases. E.g. for a file like:

```

using namespace std;

mutex g_mutex;

double worker()
{
    lock_guard<mutex> guard(g_mutex);
    uniform_real_distribution<double> uniform(-1E5, 1E5);
    default_random_engine engine;
    double s = 0;
    for (int i = 0; i < 1000; ++i) {
        s += norm(complex<double>(uniform(engine), uniform(engine)));
    }
    cout << s << endl;
    return s;
}

int main()
{
    vector<std::future<double>> results;
    for (int i = 0; i < 10000; ++i) {
        results.push_back(async(launch::async, worker));
    }
    return 0;
}
```

Compile it with `g++ -g -O2 -lpthread cpp-locking.cpp  -o cpp-locking`,
then record it with `perf record --call-graph dwarf -e
sched:sched_switch`.

When you analyze it with `perf script` and libunwind, you should see:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
            7f38e4252d0b arena_get2.part.4+0x2fb (/usr/lib/libc-2.28.so)
            7f38e4255b1c tcache_init.part.6+0xec (/usr/lib/libc-2.28.so)
            7f38e42569e5 __GI___libc_malloc+0x115 (inlined)
            7f38e4241790 __GI__IO_file_doallocate+0x90 (inlined)
            7f38e424fbbf __GI__IO_doallocbuf+0x4f (inlined)
            7f38e424ee47 __GI__IO_file_overflow+0x197 (inlined)
            7f38e424df36 _IO_new_file_xsputn+0x116 (inlined)
            7f38e4242bfb __GI__IO_fwrite+0xdb (inlined)
            7f38e463fa6d std::basic_streambuf<char, std::char_traits<char> >::sputn(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> >::_M_put(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::__write<char>(std::ostreambuf_iterator<char, std::char_traits<char> >, char const*, int)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_float<double>(std::ostreambuf_iterator<c>
            7f38e464bd70 std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, double) const+0x90 (inl>
            7f38e464bd70 std::ostream& std::ostream::_M_insert<double>(double)+0x90 (/usr/lib/libstdc++.so.6.0.25)
            563b9cb502f7 std::ostream::operator<<(double)+0xb7 (inlined)
            563b9cb502f7 worker()+0xb7 (/ssd/milian/projects/kdab/rnd/hotspot/build/tests/test-clients/cpp-locking/cpp-locking)
            563b9cb506fb double std::__invoke_impl<double, double (*)()>(std::__invoke_other, double (*&&)())+0x2b (inlined)
            563b9cb506fb std::__invoke_result<double (*)()>::type std::__invoke<double (*)()>(double (*&&)())+0x2b (inlined)
            563b9cb506fb decltype (__invoke((_S_declval<0ul>)())) std::thread::_Invoker<std::tuple<double (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>)+0x2b (inlined)
            563b9cb506fb std::thread::_Invoker<std::tuple<double (*)()> >::operator()()+0x2b (inlined)
            563b9cb506fb std::__future_base::_Task_setter<std::unique_ptr<std::__future_base::_Result<double>, std::__future_base::_Result_base::_Deleter>, std::thread::_Invoker<std::tuple<double (*)()> >, dou>
            563b9cb506fb std::_Function_handler<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> (), std::__future_base::_Task_setter<std::unique_ptr<std::__future_>
            563b9cb507e8 std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>::operator()() const+0x28 (inlined)
            563b9cb507e8 std::__future_base::_State_baseV2::_M_do_set(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>*, bool*)+0x28 (/ssd/milian/>
            7f38e46d24fe __pthread_once_slow+0xbe (/usr/lib/libpthread-2.28.so)
            563b9cb51149 __gthread_once+0xe9 (inlined)
            563b9cb51149 void std::call_once<void (std::__future_base::_State_baseV2::*)(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>*, bool*)>
            563b9cb51149 std::__future_base::_State_baseV2::_M_set_result(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>, bool)+0xe9 (inlined)
            563b9cb51149 std::__future_base::_Async_state_impl<std::thread::_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread::_Invoker<std::tuple<double (*)()> >&&)::{lambda()#1}::op>
            563b9cb51149 void std::__invoke_impl<void, std::__future_base::_Async_state_impl<std::thread::_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread::_Invoker<std::tuple<double>
            563b9cb51149 std::__invoke_result<std::__future_base::_Async_state_impl<std::thread::_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread::_Invoker<std::tuple<double (*)()> >>
            563b9cb51149 decltype (__invoke((_S_declval<0ul>)())) std::thread::_Invoker<std::tuple<std::__future_base::_Async_state_impl<std::thread::_Invoker<std::tuple<double (*)()> >, double>::_Async_state_>
            563b9cb51149 std::thread::_Invoker<std::tuple<std::__future_base::_Async_state_impl<std::thread::_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread::_Invoker<std::tuple<dou>
            563b9cb51149 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__future_base::_Async_state_impl<std::thread::_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread>
            7f38e45f0062 execute_native_thread_routine+0x12 (/usr/lib/libstdc++.so.6.0.25)
            7f38e46caa9c start_thread+0xfc (/usr/lib/libpthread-2.28.so)
            7f38e42ccb22 __GI___clone+0x42 (inlined)
```

Before this patch, using libdwfl, you would see:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
        a041161e77950c5c [unknown] ([unknown])
```

With this patch applied, we get a bit further in unwinding:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
            7f38e4252d0b arena_get2.part.4+0x2fb (/usr/lib/libc-2.28.so)
            7f38e4255b1c tcache_init.part.6+0xec (/usr/lib/libc-2.28.so)
            7f38e42569e5 __GI___libc_malloc+0x115 (inlined)
            7f38e4241790 __GI__IO_file_doallocate+0x90 (inlined)
            7f38e424fbbf __GI__IO_doallocbuf+0x4f (inlined)
            7f38e424ee47 __GI__IO_file_overflow+0x197 (inlined)
            7f38e424df36 _IO_new_file_xsputn+0x116 (inlined)
            7f38e4242bfb __GI__IO_fwrite+0xdb (inlined)
            7f38e463fa6d std::basic_streambuf<char, std::char_traits<char> >::sputn(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> >::_M_put(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::__write<char>(std::ostreambuf_iterator<char, std::char_traits<char> >, char const*, int)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_float<double>(std::ostreambuf_iterator<c>
            7f38e464bd70 std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, double) const+0x90 (inl>
            7f38e464bd70 std::ostream& std::ostream::_M_insert<double>(double)+0x90 (/usr/lib/libstdc++.so.6.0.25)
            563b9cb502f7 std::ostream::operator<<(double)+0xb7 (inlined)
            563b9cb502f7 worker()+0xb7 (/ssd/milian/projects/kdab/rnd/hotspot/build/tests/test-clients/cpp-locking/cpp-locking)
        6eab825c1ee3e4ff [unknown] ([unknown])
```

Note that the backtrace is still stopping too early, when compared to
the nice results obtained via libunwind. It's unclear so far what the
reason for that is.

Committer note:

Further comment by Milian on the thread started on the Link: tag below:

 ---
The remaining issue is due to a bug in elfutils:

https://sourceware.org/ml/elfutils-devel/2018-q4/msg00089.html

With both patches applied, libunwind and elfutils produce the same output for
the above scenario.
 ---

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181029141644.3907-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Ido Schimmel says:

====================
mlxsw: Enable minimum shaper on MC TCs

Petr says:

An MC-aware mode was introduced in commit 7b81953 ("mlxsw:
spectrum: Configure MC-aware mode on mlxsw ports"). In MC-aware mode,
BUM traffic gets a special treatment by being assigned to a separate set
of traffic classes 8..15. Pairs of TCs 0 and 8, 1 and 9, etc., are then
configured to strictly prioritize the lower-numbered ones. The intention
is to prevent BUM traffic from flooding the switch and push out all UC
traffic, which would otherwise happen, and instead give UC traffic
precedence.

However strictly prioritizing UC traffic has the effect that UC overload
pushes out all BUM traffic, such as legitimate ARP queries. These
packets are kept in queues for a while, but under sustained UC overload,
their lifetime eventually expires and these packets are dropped. That is
detrimental to network performance as well.

In this patchset, MC TCs (8..15) are configured with minimum shaper of
200Mbps (a minimum permitted value) to allow a trickle of necessary
control traffic to get through.

First in patch #1, the QEEC register is extended with fields necessary
to configure the minimum shaper.

In patch #2, minimum shaper is enabled on TCs 8..15.

In patches #3 and #4, first the MC-awareness test is tweaked to support
the minimum shaper, and then a new test is introduced to test that MC
traffic behaves well under UC overload.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

Increase kasan instrumented kernel stack size from 32k to 64k. Other
architectures seems to get away with just doubling kernel stack size under
kasan, but on s390 this appears to be not enough due to bigger frame size.
The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE
vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting
stack overflow is fs sync on xfs filesystem:

 #0 [9a0681e8]  704 bytes  check_usage at 34b1fc
 #1 [9a0684a8]  432 bytes  check_usage at 34c710
 #2 [9a068658]  1048 bytes  validate_chain at 35044a
 #3 [9a068a70]  312 bytes  __lock_acquire at 3559fe
 #4 [9a068ba8]  440 bytes  lock_acquire at 3576ee
 #5 [9a068d60]  104 bytes  _raw_spin_lock at 21b44e0
 torvalds#6 [9a068dc8]  1992 bytes  enqueue_entity at 2dbf72
 torvalds#7 [9a069590]  1496 bytes  enqueue_task_fair at 2df5f0
 torvalds#8 [9a069b68]  64 bytes  ttwu_do_activate at 28f438
 torvalds#9 [9a069ba8]  552 bytes  try_to_wake_up at 298c4c
 torvalds#10 [9a069dd0]  168 bytes  wake_up_worker at 23f97c
 torvalds#11 [9a069e78]  200 bytes  insert_work at 23fc2e
 torvalds#12 [9a069f40]  648 bytes  __queue_work at 2487c0
 torvalds#13 [9a06a1c8]  200 bytes  __queue_delayed_work at 24db28
 torvalds#14 [9a06a290]  248 bytes  mod_delayed_work_on at 24de84
 torvalds#15 [9a06a388]  24 bytes  kblockd_mod_delayed_work_on at 153e2a0
 torvalds#16 [9a06a3a]  288 bytes  __blk_mq_delay_run_hw_queue at 158168c
 torvalds#17 [9a06a4c0]  192 bytes  blk_mq_run_hw_queue at 1581a3c
 torvalds#18 [9a06a58]  184 bytes  blk_mq_sched_insert_requests at 15a2192
 torvalds#19 [9a06a638]  1024 bytes  blk_mq_flush_plug_list at 1590f3a
 torvalds#20 [9a06aa38]  704 bytes  blk_flush_plug_list at 1555028
 torvalds#21 [9a06acf8]  320 bytes  schedule at 219e476
 torvalds#22 [9a06ae38]  760 bytes  schedule_timeout at 21b0aac
 torvalds#23 [9a06b130]  408 bytes  wait_for_common at 21a1706
 torvalds#24 [9a06b2c8]  360 bytes  xfs_buf_iowait at fa1540
 torvalds#25 [9a06b430]  256 bytes  __xfs_buf_submit at fadae6
 torvalds#26 [9a06b530]  264 bytes  xfs_buf_read_map at fae3f6
 torvalds#27 [9a06b638]  656 bytes  xfs_trans_read_buf_map at 10ac9a8
 torvalds#28 [9a06b8c]  304 bytes  xfs_btree_kill_root at e72426
 torvalds#29 [9a06b9f8]  288 bytes  xfs_btree_lookup_get_block at e7bc5e
 torvalds#30 [9a06bb18]  624 bytes  xfs_btree_lookup at e7e1a6
 torvalds#31 [9a06bd88]  2664 bytes  xfs_alloc_ag_vextent_near at dfa070
 torvalds#32 [9a06c7f0]  144 bytes  xfs_alloc_ag_vextent at dff3ca
 torvalds#33 [9a06c880]  1128 bytes  xfs_alloc_vextent at e05fce
 torvalds#34 [9a06cce8]  584 bytes  xfs_bmap_btalloc at e58342
 torvalds#35 [9a06cf30]  1336 bytes  xfs_bmapi_write at e618de
 torvalds#36 [9a06d468]  776 bytes  xfs_iomap_write_allocate at ff678e
 torvalds#37 [9a06d770]  720 bytes  xfs_map_blocks at f82af8
 torvalds#38 [9a06da40]  928 bytes  xfs_writepage_map at f83cd6
 torvalds#39 [9a06dde0]  320 bytes  xfs_do_writepage at f85872
 torvalds#40 [9a06df20]  1320 bytes  write_cache_pages at 73dfe8
 torvalds#41 [9a06e448]  208 bytes  xfs_vm_writepages at f7f892
 torvalds#42 [9a06e518]  88 bytes  do_writepages at 73fe6a
 torvalds#43 [9a06e57]  872 bytes  __writeback_single_inode at a20cb6
 torvalds#44 [9a06e8d8]  664 bytes  writeback_sb_inodes at a23be2
 torvalds#45 [9a06eb70]  296 bytes  __writeback_inodes_wb at a242e0
 torvalds#46 [9a06ec98]  928 bytes  wb_writeback at a2500e
 torvalds#47 [9a06f038]  848 bytes  wb_do_writeback at a260ae
 torvalds#48 [9a06f388]  536 bytes  wb_workfn at a28228
 torvalds#49 [9a06f5a0]  1088 bytes  process_one_work at 24a234
 torvalds#50 [9a06f9e0]  1120 bytes  worker_thread at 24ba26
 torvalds#51 [9a06fe40]  104 bytes  kthread at 26545a
 #52 [9a06fea]             kernel_thread_starter at 21b6b62

To be able to increase the stack size to 64k reuse LLILL instruction
in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE
(65192) value as unsigned.

Reported-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

…_nlattr

Otherwise, we hit a NULL pointer deference since handlers always assume
default timeout policy is passed.

  netlink: 24 bytes leftover after parsing attributes in process `syz-executor2'.
  kasan: CONFIG_KASAN_INLINE enabled
  kasan: GPF could be caused by NULL-ptr deref or user memory access
  general protection fault: 0000 [#1] PREEMPT SMP KASAN
  CPU: 0 PID: 9575 Comm: syz-executor1 Not tainted 4.19.0+ torvalds#312
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  RIP: 0010:icmp_timeout_obj_to_nlattr+0x77/0x170 net/netfilter/nf_conntrack_proto_icmp.c:297

Fixes: c779e84 ("netfilter: conntrack: remove get_timeout() indirection")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Mike Galbraith reported a regression caused by the commit 9b6f7e1
("mm: rework memcg kernel stack accounting") on a system with
"cgroup_disable=memory" boot option: the system panics with the following
stack trace:

  BUG: unable to handle kernel NULL pointer dereference at 00000000000000f8
  PGD 0 P4D 0
  Oops: 0002 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 1 Comm: systemd Not tainted 4.19.0-preempt+ torvalds#410
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20180531_142017-buildhw-08.phx2.fed4
  RIP: 0010:page_counter_try_charge+0x22/0xc0
  Code: 41 5d c3 c3 0f 1f 40 00 0f 1f 44 00 00 48 85 ff 0f 84 a7 00 00 00 41 56 48 89 f8 49 89 fe 49
  Call Trace:
   try_charge+0xcb/0x780
   memcg_kmem_charge_memcg+0x28/0x80
   memcg_kmem_charge+0x8b/0x1d0
   copy_process.part.41+0x1ca/0x2070
   _do_fork+0xd7/0x3d0
   do_syscall_64+0x5a/0x180
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

The problem occurs because get_mem_cgroup_from_current() returns the NULL
pointer if memory controller is disabled.  Let's check if this is a case
at the beginning of memcg_kmem_charge() and just return 0 if
mem_cgroup_disabled() returns true.  This is how we handle this case in
many other places in the memory controller code.

Link: http://lkml.kernel.org/r/20181029215123.17830-1-guro@fb.com
Fixes: 9b6f7e1 ("mm: rework memcg kernel stack accounting")
Signed-off-by: Roman Gushchin <guro@fb.com>
Reported-by: Mike Galbraith <efault@gmx.de>
Acked-by: Rik van Riel <riel@surriel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We have received a bug report that unbinding a large pmem (>1TB) can
result in a soft lockup:

  NMI watchdog: BUG: soft lockup - CPU#9 stuck for 23s! [ndctl:4365]
  [...]
  Supported: Yes
  CPU: 9 PID: 4365 Comm: ndctl Not tainted 4.12.14-94.40-default #1 SLE12-SP4
  Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
  task: ffff9cce7d4410c0 task.stack: ffffbe9eb1bc4000
  RIP: 0010:__put_page+0x62/0x80
  Call Trace:
   devm_memremap_pages_release+0x152/0x260
   release_nodes+0x18d/0x1d0
   device_release_driver_internal+0x160/0x210
   unbind_store+0xb3/0xe0
   kernfs_fop_write+0x102/0x180
   __vfs_write+0x26/0x150
   vfs_write+0xad/0x1a0
   SyS_write+0x42/0x90
   do_syscall_64+0x74/0x150
   entry_SYSCALL_64_after_hwframe+0x3d/0xa2
  RIP: 0033:0x7fd13166b3d0

It has been reported on an older (4.12) kernel but the current upstream
code doesn't cond_resched in the hot remove code at all and the given
range to remove might be really large.  Fix the issue by calling
cond_resched once per memory section.

Link: http://lkml.kernel.org/r/20181031125840.23982-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Dan Williams <dan.j.williams@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Due to what appears to be a copy/paste error, the opening ENTRY()
of cpu_v7_hvc_switch_mm() lacks a matching ENDPROC(), and instead,
the one for cpu_v7_smc_switch_mm() is duplicated.

Given that it is ENDPROC() that emits the Thumb annotation, the
cpu_v7_hvc_switch_mm() routine will be called in ARM mode on a
Thumb2 kernel, resulting in the following splat:

  Internal error: Oops - undefined instruction: 0 [#1] SMP THUMB2
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.18.0-rc1-00030-g4d28ad89189d-dirty torvalds#488
  Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
  PC is at cpu_v7_hvc_switch_mm+0x12/0x18
  LR is at flush_old_exec+0x31b/0x570
  pc : [<c0316efe>]    lr : [<c04117c7>]    psr: 00000013
  sp : ee899e50  ip : 00000000  fp : 00000001
  r10: eda28f34  r9 : eda31800  r8 : c12470e0
  r7 : eda1fc00  r6 : eda53000  r5 : 00000000  r4 : ee88c000
  r3 : c0316eec  r2 : 00000001  r1 : eda53000  r0 : 6da6c000
  Flags: nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none

Note the 'ISA ARM' in the last line.

Fix this by using the correct name in ENDPROC().

Cc: <stable@vger.kernel.org>
Fixes: 1011510 ("ARM: spectre-v2: add firmware based hardening")
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

When the cow_file_range fails, the related resources are unlocked
according to the range [start..end), so the unlock cannot be repeated in
run_delalloc_nocow.

In some cases (e.g. cur_offset <= end && cow_start != -1), cur_offset is
not updated correctly, so move the cur_offset update before
cow_file_range.

  kernel BUG at mm/page-writeback.c:2663!
  Internal error: Oops - BUG: 0 [#1] SMP
  CPU: 3 PID: 31525 Comm: kworker/u8:7 Tainted: P O
  Hardware name: Realtek_RTD1296 (DT)
  Workqueue: writeback wb_workfn (flush-btrfs-1)
  task: ffffffc076db3380 ti: ffffffc02e9ac000 task.ti: ffffffc02e9ac000
  PC is at clear_page_dirty_for_io+0x1bc/0x1e8
  LR is at clear_page_dirty_for_io+0x14/0x1e8
  pc : [<ffffffc00033c91c>] lr : [<ffffffc00033c774>] pstate: 40000145
  sp : ffffffc02e9af4f0
  Process kworker/u8:7 (pid: 31525, stack limit = 0xffffffc02e9ac020)
  Call trace:
  [<ffffffc00033c91c>] clear_page_dirty_for_io+0x1bc/0x1e8
  [<ffffffbffc514674>] extent_clear_unlock_delalloc+0x1e4/0x210 [btrfs]
  [<ffffffbffc4fb168>] run_delalloc_nocow+0x3b8/0x948 [btrfs]
  [<ffffffbffc4fb948>] run_delalloc_range+0x250/0x3a8 [btrfs]
  [<ffffffbffc514c0c>] writepage_delalloc.isra.21+0xbc/0x1d8 [btrfs]
  [<ffffffbffc516048>] __extent_writepage+0xe8/0x248 [btrfs]
  [<ffffffbffc51630c>] extent_write_cache_pages.isra.17+0x164/0x378 [btrfs]
  [<ffffffbffc5185a8>] extent_writepages+0x48/0x68 [btrfs]
  [<ffffffbffc4f5828>] btrfs_writepages+0x20/0x30 [btrfs]
  [<ffffffc00033d758>] do_writepages+0x30/0x88
  [<ffffffc0003ba0f4>] __writeback_single_inode+0x34/0x198
  [<ffffffc0003ba6c4>] writeback_sb_inodes+0x184/0x3c0
  [<ffffffc0003ba96c>] __writeback_inodes_wb+0x6c/0xc0
  [<ffffffc0003bac20>] wb_writeback+0x1b8/0x1c0
  [<ffffffc0003bb0f0>] wb_workfn+0x150/0x250
  [<ffffffc0002b0014>] process_one_work+0x1dc/0x388
  [<ffffffc0002b02f0>] worker_thread+0x130/0x500
  [<ffffffc0002b6344>] kthread+0x10c/0x110
  [<ffffffc000284590>] ret_from_fork+0x10/0x40
  Code: d503201f a9025bb5 a90363b f90023b (d4210000)

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>

… block

If we attempt to deduplicate the last block of a file A into the middle of
a file B, and file A's size is not a multiple of the block size, we end
rounding the deduplication length to 0 bytes, to avoid the data corruption
issue fixed by commit de02b9f ("Btrfs: fix data corruption when
deduplicating between different files"). However a length of zero will
cause the insertion of an extent state with a start value greater (by 1)
then the end value, leading to a corrupt extent state that will trigger a
warning and cause chaos such as an infinite loop during inode eviction.
Example trace:

 [96049.833585] ------------[ cut here ]------------
 [96049.833714] WARNING: CPU: 0 PID: 24448 at fs/btrfs/extent_io.c:436 insert_state+0x101/0x120 [btrfs]
 [96049.833767] CPU: 0 PID: 24448 Comm: xfs_io Not tainted 4.19.0-rc7-btrfs-next-39 #1
 [96049.833768] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
 [96049.833780] RIP: 0010:insert_state+0x101/0x120 [btrfs]
 [96049.833783] RSP: 0018:ffffafd2c3707af0 EFLAGS: 00010282
 [96049.833785] RAX: 0000000000000000 RBX: 000000000004dfff RCX: 0000000000000006
 [96049.833786] RDX: 0000000000000007 RSI: ffff99045c143230 RDI: ffff99047b2168a0
 [96049.833787] RBP: ffff990457851cd0 R08: 0000000000000001 R09: 0000000000000000
 [96049.833787] R10: ffffafd2c3707ab8 R11: 0000000000000000 R12: ffff9903b93b12c8
 [96049.833788] R13: 000000000004e000 R14: ffffafd2c3707b80 R15: ffffafd2c3707b78
 [96049.833790] FS:  00007f5c14e7d700(0000) GS:ffff99047b200000(0000) knlGS:0000000000000000
 [96049.833791] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [96049.833792] CR2: 00007f5c146abff8 CR3: 0000000115f4c004 CR4: 00000000003606f0
 [96049.833795] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [96049.833796] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [96049.833796] Call Trace:
 [96049.833809]  __set_extent_bit+0x46c/0x6a0 [btrfs]
 [96049.833823]  lock_extent_bits+0x6b/0x210 [btrfs]
 [96049.833831]  ? _raw_spin_unlock+0x24/0x30
 [96049.833841]  ? test_range_bit+0xdf/0x130 [btrfs]
 [96049.833853]  lock_extent_range+0x8e/0x150 [btrfs]
 [96049.833864]  btrfs_double_extent_lock+0x78/0xb0 [btrfs]
 [96049.833875]  btrfs_extent_same_range+0x14e/0x550 [btrfs]
 [96049.833885]  ? rcu_read_lock_sched_held+0x3f/0x70
 [96049.833890]  ? __kmalloc_node+0x2b0/0x2f0
 [96049.833899]  ? btrfs_dedupe_file_range+0x19a/0x280 [btrfs]
 [96049.833909]  btrfs_dedupe_file_range+0x270/0x280 [btrfs]
 [96049.833916]  vfs_dedupe_file_range_one+0xd9/0xe0
 [96049.833919]  vfs_dedupe_file_range+0x131/0x1b0
 [96049.833924]  do_vfs_ioctl+0x272/0x6e0
 [96049.833927]  ? __fget+0x113/0x200
 [96049.833931]  ksys_ioctl+0x70/0x80
 [96049.833933]  __x64_sys_ioctl+0x16/0x20
 [96049.833937]  do_syscall_64+0x60/0x1b0
 [96049.833939]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [96049.833941] RIP: 0033:0x7f5c1478ddd7
 [96049.833943] RSP: 002b:00007ffe15b196a8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
 [96049.833945] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5c1478ddd7
 [96049.833946] RDX: 00005625ece322d0 RSI: 00000000c0189436 RDI: 0000000000000004
 [96049.833947] RBP: 0000000000000000 R08: 00007f5c14a46f48 R09: 0000000000000040
 [96049.833948] R10: 0000000000000541 R11: 0000000000000202 R12: 0000000000000000
 [96049.833949] R13: 0000000000000000 R14: 0000000000000004 R15: 00005625ece322d0
 [96049.833954] irq event stamp: 6196
 [96049.833956] hardirqs last  enabled at (6195): [<ffffffff91b00663>] console_unlock+0x503/0x640
 [96049.833958] hardirqs last disabled at (6196): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
 [96049.833959] softirqs last  enabled at (6114): [<ffffffff92600370>] __do_softirq+0x370/0x421
 [96049.833964] softirqs last disabled at (6095): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
 [96049.833965] ---[ end trace db7b05f01b7fa10c ]---
 [96049.935816] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
 [96049.935822] irq event stamp: 6584
 [96049.935823] hardirqs last  enabled at (6583): [<ffffffff91b00663>] console_unlock+0x503/0x640
 [96049.935825] hardirqs last disabled at (6584): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
 [96049.935827] softirqs last  enabled at (6328): [<ffffffff92600370>] __do_softirq+0x370/0x421
 [96049.935828] softirqs last disabled at (6313): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
 [96049.935829] ---[ end trace db7b05f01b7fa123 ]---
 [96049.935840] ------------[ cut here ]------------
 [96049.936065] WARNING: CPU: 1 PID: 24463 at fs/btrfs/extent_io.c:436 insert_state+0x101/0x120 [btrfs]
 [96049.936107] CPU: 1 PID: 24463 Comm: umount Tainted: G        W         4.19.0-rc7-btrfs-next-39 #1
 [96049.936108] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
 [96049.936117] RIP: 0010:insert_state+0x101/0x120 [btrfs]
 [96049.936119] RSP: 0018:ffffafd2c3637bc0 EFLAGS: 00010282
 [96049.936120] RAX: 0000000000000000 RBX: 000000000004dfff RCX: 0000000000000006
 [96049.936121] RDX: 0000000000000007 RSI: ffff990445cf88e0 RDI: ffff99047b2968a0
 [96049.936122] RBP: ffff990457851cd0 R08: 0000000000000001 R09: 0000000000000000
 [96049.936123] R10: ffffafd2c3637b88 R11: 0000000000000000 R12: ffff9904574301e8
 [96049.936124] R13: 000000000004e000 R14: ffffafd2c3637c50 R15: ffffafd2c3637c48
 [96049.936125] FS:  00007fe4b87e72c0(0000) GS:ffff99047b280000(0000) knlGS:0000000000000000
 [96049.936126] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [96049.936128] CR2: 00005562e52618d8 CR3: 00000001151c8005 CR4: 00000000003606e0
 [96049.936129] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [96049.936131] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [96049.936131] Call Trace:
 [96049.936141]  __set_extent_bit+0x46c/0x6a0 [btrfs]
 [96049.936154]  lock_extent_bits+0x6b/0x210 [btrfs]
 [96049.936167]  btrfs_evict_inode+0x1e1/0x5a0 [btrfs]
 [96049.936172]  evict+0xbf/0x1c0
 [96049.936174]  dispose_list+0x51/0x80
 [96049.936176]  evict_inodes+0x193/0x1c0
 [96049.936180]  generic_shutdown_super+0x3f/0x110
 [96049.936182]  kill_anon_super+0xe/0x30
 [96049.936189]  btrfs_kill_super+0x13/0x100 [btrfs]
 [96049.936191]  deactivate_locked_super+0x3a/0x70
 [96049.936193]  cleanup_mnt+0x3b/0x80
 [96049.936195]  task_work_run+0x93/0xc0
 [96049.936198]  exit_to_usermode_loop+0xfa/0x100
 [96049.936201]  do_syscall_64+0x17f/0x1b0
 [96049.936202]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [96049.936204] RIP: 0033:0x7fe4b80cfb37
 [96049.936206] RSP: 002b:00007ffff092b688 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [96049.936207] RAX: 0000000000000000 RBX: 00005562e5259060 RCX: 00007fe4b80cfb37
 [96049.936208] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00005562e525faa0
 [96049.936209] RBP: 00005562e525faa0 R08: 00005562e525f770 R09: 0000000000000015
 [96049.936210] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fe4b85d1e64
 [96049.936211] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
 [96049.936211] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
 [96049.936216] irq event stamp: 6616
 [96049.936219] hardirqs last  enabled at (6615): [<ffffffff91b00663>] console_unlock+0x503/0x640
 [96049.936219] hardirqs last disabled at (6616): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
 [96049.936222] softirqs last  enabled at (6328): [<ffffffff92600370>] __do_softirq+0x370/0x421
 [96049.936222] softirqs last disabled at (6313): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
 [96049.936223] ---[ end trace db7b05f01b7fa124 ]---

The second stack trace, from inode eviction, is repeated forever due to
the infinite loop during eviction.

This is the same type of problem fixed way back in 2015 by commit
113e828 ("Btrfs: fix inode eviction infinite loop after extent_same
ioctl") and commit ccccf3d ("Btrfs: fix inode eviction infinite loop
after cloning into it").

So fix this by returning immediately if the deduplication range length
gets rounded down to 0 bytes, as there is nothing that needs to be done in
such case.

Example reproducer:

 $ mkfs.btrfs -f /dev/sdb
 $ mount /dev/sdb /mnt

 $ xfs_io -f -c "pwrite -S 0xe6 0 100" /mnt/foo
 $ xfs_io -f -c "pwrite -S 0xe6 0 1M" /mnt/bar

 # Unmount the filesystem and mount it again so that we start without any
 # extent state records when we ask for the deduplication.
 $ umount /mnt
 $ mount /dev/sdb /mnt

 $ xfs_io -c "dedupe /mnt/foo 0 500K 100" /mnt/bar

 # This unmount triggers the infinite loop.
 $ umount /mnt

A test case for fstests will follow soon.

Fixes: de02b9f ("Btrfs: fix data corruption when deduplicating between different files")
CC: <stable@vger.kernel.org> # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Following on from this patch: https://lkml.org/lkml/2017/11/3/516,
Corsair K70 LUX RGB keyboards also require the DELAY_INIT quirk to
start correctly at boot.

Dmesg output:
usb 1-6: string descriptor 0 read error: -110
usb 1-6: New USB device found, idVendor=1b1c, idProduct=1b33
usb 1-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-6: can't set config #1, error -110

Signed-off-by: Emmanuel Pescosta <emmanuelpescosta099@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Raydium USB touchscreen fails to set config if LPM is enabled:
[    2.030658] usb 1-8: New USB device found, idVendor=2386, idProduct=3119
[    2.030659] usb 1-8: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[    2.030660] usb 1-8: Product: Raydium Touch System
[    2.030661] usb 1-8: Manufacturer: Raydium Corporation
[    7.132209] usb 1-8: can't set config #1, error -110

Same behavior can be observed on 2386:3114.

Raydium claims the touchscreen supports LPM under Windows, so I used
Microsoft USB Test Tools (MUTT) [1] to check its LPM status. MUTT shows
that the LPM doesn't work under Windows, either. So let's just disable LPM
for Raydium touchscreens.

[1] https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/usb-test-tools

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There's a race between close_ctree() and cleaner_kthread().
close_ctree() sets btrfs_fs_closing(), and the cleaner stops when it
sees it set, but this is racy; the cleaner might have already checked
the bit and could be cleaning stuff. In particular, if it deletes unused
block groups, it will create delayed iputs for the free space cache
inodes. As of "btrfs: don't run delayed_iputs in commit", we're no
longer running delayed iputs after a commit. Therefore, if the cleaner
creates more delayed iputs after delayed iputs are run in
btrfs_commit_super(), we will leak inodes on unmount and get a busy
inode crash from the VFS.

Fix it by parking the cleaner before we actually close anything. Then,
any remaining delayed iputs will always be handled in
btrfs_commit_super(). This also ensures that the commit in close_ctree()
is really the last commit, so we can get rid of the commit in
cleaner_kthread().

The fstest/generic/475 followed by 476 can trigger a crash that
manifests as a slab corruption caused by accessing the freed kthread
structure by a wake up function. Sample trace:

[ 5657.077612] BUG: unable to handle kernel NULL pointer dereference at 00000000000000cc
[ 5657.079432] PGD 1c57a067 P4D 1c57a067 PUD da10067 PMD 0
[ 5657.080661] Oops: 0000 [#1] PREEMPT SMP
[ 5657.081592] CPU: 1 PID: 5157 Comm: fsstress Tainted: G        W         4.19.0-rc8-default+ torvalds#323
[ 5657.083703] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014
[ 5657.086577] RIP: 0010:shrink_page_list+0x2f9/0xe90
[ 5657.091937] RSP: 0018:ffffb5c745c8f728 EFLAGS: 00010287
[ 5657.092953] RAX: 0000000000000074 RBX: ffffb5c745c8f830 RCX: 0000000000000000
[ 5657.094590] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a8747fdf3d0
[ 5657.095987] RBP: ffffb5c745c8f9e0 R08: 0000000000000000 R09: 0000000000000000
[ 5657.097159] R10: ffff9a8747fdf5e8 R11: 0000000000000000 R12: ffffb5c745c8f788
[ 5657.098513] R13: ffff9a877f6ff2c0 R14: ffff9a877f6ff2c8 R15: dead000000000200
[ 5657.099689] FS:  00007f948d853b80(0000) GS:ffff9a877d600000(0000) knlGS:0000000000000000
[ 5657.101032] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5657.101953] CR2: 00000000000000cc CR3: 00000000684bd000 CR4: 00000000000006e0
[ 5657.103159] Call Trace:
[ 5657.103776]  shrink_inactive_list+0x194/0x410
[ 5657.104671]  shrink_node_memcg.constprop.84+0x39a/0x6a0
[ 5657.105750]  shrink_node+0x62/0x1c0
[ 5657.106529]  try_to_free_pages+0x1a4/0x500
[ 5657.107408]  __alloc_pages_slowpath+0x2c9/0xb20
[ 5657.108418]  __alloc_pages_nodemask+0x268/0x2b0
[ 5657.109348]  kmalloc_large_node+0x37/0x90
[ 5657.110205]  __kmalloc_node+0x236/0x310
[ 5657.111014]  kvmalloc_node+0x3e/0x70

Fixes: 30928e9 ("btrfs: don't run delayed_iputs in commit")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add trace ]
Signed-off-by: David Sterba <dsterba@suse.com>

[why]
Removing connector reusage from DM to match the rest of the tree ended
up revealing an issue that was surprisingly subtle. The original amdgpu
code for DC that was submitted appears to have left a chunk in
dm_dp_create_fake_mst_encoder() that tries to find a "master encoder",
the likes of which isn't actually used or stored anywhere. It does so at
the wrong time as well by trying to access parts of the drm_connector
from the encoder init before it's actually been initialized. This
results in a NULL pointer deref on MST hotplugs:

[  160.696613] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[  160.697234] PGD 0 P4D 0
[  160.697814] Oops: 0010 [#1] SMP PTI
[  160.698430] CPU: 2 PID: 64 Comm: kworker/2:1 Kdump: loaded Tainted: G           O      4.19.0Lyude-Test+ #2
[  160.699020] Hardware name: HP HP ZBook 15 G4/8275, BIOS P70 Ver. 01.22 05/17/2018
[  160.699672] Workqueue: events_long drm_dp_mst_link_probe_work [drm_kms_helper]
[  160.700322] RIP: 0010:          (null)
[  160.700920] Code: Bad RIP value.
[  160.701541] RSP: 0018:ffffc9000029fc78 EFLAGS: 00010206
[  160.702183] RAX: 0000000000000000 RBX: ffff8804440ed468 RCX: ffff8804440e9158
[  160.702778] RDX: 0000000000000000 RSI: ffff8804556c5700 RDI: ffff8804440ed000
[  160.703408] RBP: ffff880458e21800 R08: 0000000000000002 R09: 000000005fca0a25
[  160.704002] R10: ffff88045a077a3d R11: ffff88045a077a3c R12: ffff8804440ed000
[  160.704614] R13: ffff880458e21800 R14: ffff8804440e9000 R15: ffff8804440e9000
[  160.705260] FS:  0000000000000000(0000) GS:ffff88045f280000(0000) knlGS:0000000000000000
[  160.705854] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  160.706478] CR2: ffffffffffffffd6 CR3: 000000000200a001 CR4: 00000000003606e0
[  160.707124] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  160.707724] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  160.708372] Call Trace:
[  160.708998]  ? dm_dp_add_mst_connector+0xed/0x1d0 [amdgpu]
[  160.709625]  ? drm_dp_add_port+0x2fa/0x470 [drm_kms_helper]
[  160.710284]  ? wake_up_q+0x54/0x70
[  160.710877]  ? __mutex_unlock_slowpath.isra.18+0xb3/0x110
[  160.711512]  ? drm_dp_dpcd_access+0xe7/0x110 [drm_kms_helper]
[  160.712161]  ? drm_dp_send_link_address+0x155/0x1e0 [drm_kms_helper]
[  160.712762]  ? drm_dp_check_and_send_link_address+0xa3/0xd0 [drm_kms_helper]
[  160.713408]  ? drm_dp_mst_link_probe_work+0x4b/0x80 [drm_kms_helper]
[  160.714013]  ? process_one_work+0x1a1/0x3a0
[  160.714667]  ? worker_thread+0x30/0x380
[  160.715326]  ? wq_update_unbound_numa+0x10/0x10
[  160.715939]  ? kthread+0x112/0x130
[  160.716591]  ? kthread_create_worker_on_cpu+0x70/0x70
[  160.717262]  ? ret_from_fork+0x35/0x40
[  160.717886] Modules linked in: amdgpu(O) vfat fat snd_hda_codec_generic joydev i915 chash gpu_sched ttm i2c_algo_bit drm_kms_helper snd_hda_codec_hdmi hp_wmi syscopyarea iTCO_wdt sysfillrect sparse_keymap sysimgblt fb_sys_fops snd_hda_intel usbhid wmi_bmof drm snd_hda_codec btusb snd_hda_core intel_rapl btrtl x86_pkg_temp_thermal btbcm btintel coretemp snd_pcm crc32_pclmul bluetooth psmouse snd_timer snd pcspkr i2c_i801 mei_me i2c_core soundcore mei tpm_tis wmi tpm_tis_core hp_accel ecdh_generic lis3lv02d tpm video rfkill acpi_pad input_polldev hp_wireless pcc_cpufreq crc32c_intel serio_raw tg3 xhci_pci xhci_hcd [last unloaded: amdgpu]
[  160.720141] CR2: 0000000000000000

Somehow the connector reusage DM was using for MST connectors managed to
paper over this issue entirely; hence why this was never caught until
now.

[how]
Since this code isn't used anywhere and seems useless anyway, we can
just drop it entirely. This appears to fix the issue on my HP ZBook with
an AMD WX4150.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

When the source and destination addresses for the cipher are the same, we
will get a NULL dereference from accessing the split destination
scatterlist memories, as shown:

[   56.565719] tcrypt:
[   56.565719] testing speed of async ecb(aes) (hisi_sec_aes_ecb) encryption
[   56.574683] tcrypt: test 0 (128 bit key, 16 byte blocks):
[   56.587585] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   56.596361] Mem abort info:
[   56.599151]   ESR = 0x96000006
[   56.602196]   Exception class = DABT (current EL), IL = 32 bits
[   56.608105]   SET = 0, FnV = 0
[   56.611149]   EA = 0, S1PTW = 0
[   56.614280] Data abort info:
[   56.617151]   ISV = 0, ISS = 0x00000006
[   56.620976]   CM = 0, WnR = 0
[   56.623930] user pgtable: 4k pages, 48-bit VAs, pgdp = (____ptrval____)
[   56.630533] [0000000000000000] pgd=0000041fc7e4d003, pud=0000041fcd9bf003, pmd=0000000000000000
[   56.639224] Internal error: Oops: 96000006 [#1] PREEMPT SMP
[   56.644782] Modules linked in: tcrypt(+)
[   56.648695] CPU: 21 PID: 2326 Comm: insmod Tainted: G        W         4.19.0-rc6-00001-g3fabfb8-dirty torvalds#716
[   56.658420] Hardware name: Huawei Taishan 2280 /D05, BIOS Hisilicon D05 IT17 Nemo 2.0 RC0 10/05/2018
[   56.667537] pstate: 20000005 (nzCv daif -PAN -UAO)
[   56.672322] pc : sec_alg_skcipher_crypto+0x318/0x748
[   56.677274] lr : sec_alg_skcipher_crypto+0x178/0x748
[   56.682224] sp : ffff0000118e3840
[   56.685525] x29: ffff0000118e3840 x28: ffff841fbb3f8118
[   56.690825] x27: 0000000000000000 x26: 0000000000000000
[   56.696125] x25: ffff841fbb3f8080 x24: ffff841fbadc0018
[   56.701425] x23: ffff000009119000 x22: ffff841fbb24e280
[   56.706724] x21: ffff841ff212e780 x20: ffff841ff212e700
[   56.712023] x19: 0000000000000001 x18: ffffffffffffffff
[   56.717322] x17: 0000000000000000 x16: 0000000000000000
[   56.722621] x15: ffff0000091196c8 x14: 72635f7265687069
[   56.727920] x13: 636b735f676c615f x12: ffff000009119940
[   56.733219] x11: 0000000000000000 x10: 00000000006080c0
[   56.738519] x9 : 0000000000000000 x8 : ffff841fbb24e480
[   56.743818] x7 : ffff841fbb24e500 x6 : ffff841ff00cdcc0
[   56.749117] x5 : 0000000000000010 x4 : 0000000000000000
[   56.754416] x3 : ffff841fbb24e380 x2 : ffff841fbb24e480
[   56.759715] x1 : 0000000000000000 x0 : ffff000008f682c8
[   56.765016] Process insmod (pid: 2326, stack limit = 0x(____ptrval____))
[   56.771702] Call trace:
[   56.774136]  sec_alg_skcipher_crypto+0x318/0x748
[   56.778740]  sec_alg_skcipher_encrypt+0x10/0x18
[   56.783259]  test_skcipher_speed+0x2a0/0x700 [tcrypt]
[   56.788298]  do_test+0x18f8/0x48c8 [tcrypt]
[   56.792469]  tcrypt_mod_init+0x60/0x1000 [tcrypt]
[   56.797161]  do_one_initcall+0x5c/0x178
[   56.800985]  do_init_module+0x58/0x1b4
[   56.804721]  load_module+0x1da4/0x2150
[   56.808456]  __se_sys_init_module+0x14c/0x1e8
[   56.812799]  __arm64_sys_init_module+0x18/0x20
[   56.817231]  el0_svc_common+0x60/0xe8
[   56.820880]  el0_svc_handler+0x2c/0x80
[   56.824615]  el0_svc+0x8/0xc
[   56.827483] Code: a94c87a3 910b200 f87b7842 f9004ba2 (b87b7821)
[   56.833564] ---[ end trace 0f63290590e93d94 ]---
Segmentation fault

Fix this by only accessing these memories when we have different src and
dst.

Fixes: 915e4e8 ("crypto: hisilicon - SEC security accelerator driver")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

LKP recently reported a hang at bootup in the floppy code:

[  245.678853] INFO: task mount:580 blocked for more than 120 seconds.
[  245.679906]       Tainted: G                T 4.19.0-rc6-00172-ga9f38e1 #1
[  245.680959] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  245.682181] mount           D 6372   580      1 0x00000004
[  245.683023] Call Trace:
[  245.683425]  __schedule+0x2df/0x570
[  245.683975]  schedule+0x2d/0x80
[  245.684476]  schedule_timeout+0x19d/0x330
[  245.685090]  ? wait_for_common+0xa5/0x170
[  245.685735]  wait_for_common+0xac/0x170
[  245.686339]  ? do_sched_yield+0x90/0x90
[  245.686935]  wait_for_completion+0x12/0x20
[  245.687571]  __floppy_read_block_0+0xfb/0x150
[  245.688244]  ? floppy_resume+0x40/0x40
[  245.688844]  floppy_revalidate+0x20f/0x240
[  245.689486]  check_disk_change+0x43/0x60
[  245.690087]  floppy_open+0x1ea/0x360
[  245.690653]  __blkdev_get+0xb4/0x4d0
[  245.691212]  ? blkdev_get+0x1db/0x370
[  245.691777]  blkdev_get+0x1f3/0x370
[  245.692351]  ? path_put+0x15/0x20
[  245.692871]  ? lookup_bdev+0x4b/0x90
[  245.693539]  blkdev_get_by_path+0x3d/0x80
[  245.694165]  mount_bdev+0x2a/0x190
[  245.694695]  squashfs_mount+0x10/0x20
[  245.695271]  ? squashfs_alloc_inode+0x30/0x30
[  245.695960]  mount_fs+0xf/0x90
[  245.696451]  vfs_kern_mount+0x43/0x130
[  245.697036]  do_mount+0x187/0xc40
[  245.697563]  ? memdup_user+0x28/0x50
[  245.698124]  ksys_mount+0x60/0xc0
[  245.698639]  sys_mount+0x19/0x20
[  245.699167]  do_int80_syscall_32+0x61/0x130
[  245.699813]  entry_INT80_32+0xc7/0xc7

showing that we never complete that read request. The reason is that
the completion setup is racy - it initializes the completion event
AFTER submitting the IO, which means that the IO could complete
before/during the init. If it does, we are passing garbage to
complete() and we may sleep forever waiting for the event to
occur.

Fixes: 7b7b68b ("floppy: bail out in open() if drive is not responding to block0 read")
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The following lockdep splat results from acquiring the init_mutex in
acpi_nfit_clear_to_send():

 WARNING: possible circular locking dependency detected
 lt-daxdev-error/7216 is trying to acquire lock:
 00000000f694db15 (&acpi_desc->init_mutex){+.+.}, at: acpi_nfit_clear_to_send+0x27/0x80 [nfit]

 but task is already holding lock:
 00000000182298f2 (&nvdimm_bus->reconfig_mutex){+.+.}, at: __nd_ioctl+0x457/0x610 [libnvdimm]

 which lock already depends on the new lock.


 the existing dependency chain (in reverse order) is:

 -> #1 (&nvdimm_bus->reconfig_mutex){+.+.}:
        nvdimm_badblocks_populate+0x41/0x150 [libnvdimm]
        nd_region_notify+0x95/0xb0 [libnvdimm]
        nd_device_notify+0x40/0x50 [libnvdimm]
        ars_complete+0x7f/0xd0 [nfit]
        acpi_nfit_scrub+0xbb/0x410 [nfit]
        process_one_work+0x22b/0x5c0
        worker_thread+0x3c/0x390
        kthread+0x11e/0x140
        ret_from_fork+0x3a/0x50

 -> #0 (&acpi_desc->init_mutex){+.+.}:
        __mutex_lock+0x83/0x980
        acpi_nfit_clear_to_send+0x27/0x80 [nfit]
        __nd_ioctl+0x474/0x610 [libnvdimm]
        nd_ioctl+0xa4/0xb0 [libnvdimm]
        do_vfs_ioctl+0xa5/0x6e0
        ksys_ioctl+0x70/0x80
        __x64_sys_ioctl+0x16/0x20
        do_syscall_64+0x60/0x210
        entry_SYSCALL_64_after_hwframe+0x49/0xbe

New infrastructure is needed to be able to perform this check without
acquiring the lock.

Fixes: 5948612 ("acpi, nfit: Further restrict userspace ARS start")
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Turns out that if you trigger an HPD storm on a system that has an MST
topology connected to it, you'll end up causing the kernel to eventually
hit a NULL deref:

[  332.339041] BUG: unable to handle kernel NULL pointer dereference at 00000000000000ec
[  332.340906] PGD 0 P4D 0
[  332.342750] Oops: 0000 [#1] SMP PTI
[  332.344579] CPU: 2 PID: 25 Comm: kworker/2:0 Kdump: loaded Tainted: G           O      4.18.0-rc3short-hpd-storm+ #2
[  332.346453] Hardware name: LENOVO 20BWS1KY00/20BWS1KY00, BIOS JBET71WW (1.35 ) 09/14/2018
[  332.348361] Workqueue: events intel_hpd_irq_storm_reenable_work [i915]
[  332.350301] RIP: 0010:intel_hpd_irq_storm_reenable_work.cold.3+0x2f/0x86 [i915]
[  332.352213] Code: 00 00 ba e8 00 00 00 48 c7 c6 c0 aa 5f a0 48 c7 c7 d0 73 62 a0 4c 89 c1 4c 89 04 24 e8 7f f5 af e0 4c 8b 04 24 44 89 f8 29 e8 <41> 39 80 ec 00 00 00 0f 85 43 13 fc ff 41 0f b6 86 b8 04 00 00 41
[  332.354286] RSP: 0018:ffffc90000147e48 EFLAGS: 00010006
[  332.356344] RAX: 0000000000000005 RBX: ffff8802c226c9d4 RCX: 0000000000000006
[  332.358404] RDX: 0000000000000000 RSI: 0000000000000082 RDI: ffff88032dc95570
[  332.360466] RBP: 0000000000000005 R08: 0000000000000000 R09: ffff88031b3dc840
[  332.362528] R10: 0000000000000000 R11: 000000031a069602 R12: ffff8802c226ca20
[  332.364575] R13: ffff8802c2268000 R14: ffff880310661000 R15: 000000000000000a
[  332.366615] FS:  0000000000000000(0000) GS:ffff88032dc80000(0000) knlGS:0000000000000000
[  332.368658] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  332.370690] CR2: 00000000000000ec CR3: 000000000200a003 CR4: 00000000003606e0
[  332.372724] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  332.374773] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  332.376798] Call Trace:
[  332.378809]  process_one_work+0x1a1/0x350
[  332.380806]  worker_thread+0x30/0x380
[  332.382777]  ? wq_update_unbound_numa+0x10/0x10
[  332.384772]  kthread+0x112/0x130
[  332.386740]  ? kthread_create_worker_on_cpu+0x70/0x70
[  332.388706]  ret_from_fork+0x35/0x40
[  332.390651] Modules linked in: i915(O) vfat fat joydev btusb btrtl btbcm btintel bluetooth ecdh_generic iTCO_wdt wmi_bmof i2c_algo_bit drm_kms_helper intel_rapl syscopyarea sysfillrect x86_pkg_temp_thermal sysimgblt coretemp fb_sys_fops crc32_pclmul drm psmouse pcspkr mei_me mei i2c_i801 lpc_ich mfd_core i2c_core tpm_tis tpm_tis_core thinkpad_acpi wmi tpm rfkill video crc32c_intel serio_raw ehci_pci xhci_pci ehci_hcd xhci_hcd [last unloaded: i915]
[  332.394963] CR2: 00000000000000ec

This appears to be due to the fact that with an MST topology, not all
intel_connector structs will have ->encoder set. So, fix this by
skipping connectors without encoders in
intel_hpd_irq_storm_reenable_work().

For those wondering, this bug was found on accident while simulating HPD
storms using a Chamelium connected to a ThinkPad T450s (Broadwell).

Changes since v1:
- Check intel_connector->mst_port instead of intel_connector->encoder

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181106213017.14563-3-lyude@redhat.com
(cherry picked from commit fee61de)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

We get the following warning:

[   47.926140] 32-bit node address hash set to 2010a0a
[   47.927202]
[   47.927433] ================================
[   47.928050] WARNING: inconsistent lock state
[   47.928661] 4.19.0+ torvalds#37 Tainted: G            E
[   47.929346] --------------------------------
[   47.929954] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   47.930116] swapper/3/0 [HC0[0]:SC1[3]:HE1:SE0] takes:
[   47.930116] 00000000af8bc31e (&(&ht->lock)->rlock){+.?.}, at: rhashtable_walk_enter+0x36/0xb0
[   47.930116] {SOFTIRQ-ON-W} state was registered at:
[   47.930116]   _raw_spin_lock+0x29/0x60
[   47.930116]   rht_deferred_worker+0x556/0x810
[   47.930116]   process_one_work+0x1f5/0x540
[   47.930116]   worker_thread+0x64/0x3e0
[   47.930116]   kthread+0x112/0x150
[   47.930116]   ret_from_fork+0x3a/0x50
[   47.930116] irq event stamp: 14044
[   47.930116] hardirqs last  enabled at (14044): [<ffffffff9a07fbba>] __local_bh_enable_ip+0x7a/0xf0
[   47.938117] hardirqs last disabled at (14043): [<ffffffff9a07fb81>] __local_bh_enable_ip+0x41/0xf0
[   47.938117] softirqs last  enabled at (14028): [<ffffffff9a0803ee>] irq_enter+0x5e/0x60
[   47.938117] softirqs last disabled at (14029): [<ffffffff9a0804a5>] irq_exit+0xb5/0xc0
[   47.938117]
[   47.938117] other info that might help us debug this:
[   47.938117]  Possible unsafe locking scenario:
[   47.938117]
[   47.938117]        CPU0
[   47.938117]        ----
[   47.938117]   lock(&(&ht->lock)->rlock);
[   47.938117]   <Interrupt>
[   47.938117]     lock(&(&ht->lock)->rlock);
[   47.938117]
[   47.938117]  *** DEADLOCK ***
[   47.938117]
[   47.938117] 2 locks held by swapper/3/0:
[   47.938117]  #0: 0000000062c64f90 ((&d->timer)){+.-.}, at: call_timer_fn+0x5/0x280
[   47.938117]  #1: 00000000ee39619c (&(&d->lock)->rlock){+.-.}, at: tipc_disc_timeout+0xc8/0x540 [tipc]
[   47.938117]
[   47.938117] stack backtrace:
[   47.938117] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G            E     4.19.0+ torvalds#37
[   47.938117] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   47.938117] Call Trace:
[   47.938117]  <IRQ>
[   47.938117]  dump_stack+0x5e/0x8b
[   47.938117]  print_usage_bug+0x1ed/0x1ff
[   47.938117]  mark_lock+0x5b5/0x630
[   47.938117]  __lock_acquire+0x4c0/0x18f0
[   47.938117]  ? lock_acquire+0xa6/0x180
[   47.938117]  lock_acquire+0xa6/0x180
[   47.938117]  ? rhashtable_walk_enter+0x36/0xb0
[   47.938117]  _raw_spin_lock+0x29/0x60
[   47.938117]  ? rhashtable_walk_enter+0x36/0xb0
[   47.938117]  rhashtable_walk_enter+0x36/0xb0
[   47.938117]  tipc_sk_reinit+0xb0/0x410 [tipc]
[   47.938117]  ? mark_held_locks+0x6f/0x90
[   47.938117]  ? __local_bh_enable_ip+0x7a/0xf0
[   47.938117]  ? lockdep_hardirqs_on+0x20/0x1a0
[   47.938117]  tipc_net_finalize+0xbf/0x180 [tipc]
[   47.938117]  tipc_disc_timeout+0x509/0x540 [tipc]
[   47.938117]  ? call_timer_fn+0x5/0x280
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  call_timer_fn+0xa1/0x280
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  run_timer_softirq+0x1f2/0x4d0
[   47.938117]  __do_softirq+0xfc/0x413
[   47.938117]  irq_exit+0xb5/0xc0
[   47.938117]  smp_apic_timer_interrupt+0xac/0x210
[   47.938117]  apic_timer_interrupt+0xf/0x20
[   47.938117]  </IRQ>
[   47.938117] RIP: 0010:default_idle+0x1c/0x140
[   47.938117] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 41 54 55 53 65 8b 2d d8 2b 74 65 0f 1f 44 00 00 e8 c6 2c 8b ff fb f4 <65> 8b 2d c5 2b 74 65 0f 1f 44 00 00 5b 5d 41 5c c3 65 8b 05 b4 2b
[   47.938117] RSP: 0018:ffffaf6ac0207ec8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
[   47.938117] RAX: ffff8f5b3735e200 RBX: 0000000000000003 RCX: 0000000000000001
[   47.938117] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8f5b3735e200
[   47.938117] RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000000
[   47.938117] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[   47.938117] R13: 0000000000000000 R14: ffff8f5b3735e200 R15: ffff8f5b3735e200
[   47.938117]  ? default_idle+0x1a/0x140
[   47.938117]  do_idle+0x1bc/0x280
[   47.938117]  cpu_startup_entry+0x19/0x20
[   47.938117]  start_secondary+0x187/0x1c0
[   47.938117]  secondary_startup_64+0xa4/0xb0

The reason seems to be that tipc_net_finalize()->tipc_sk_reinit() is
calling the function rhashtable_walk_enter() within a timer interrupt.
We fix this by executing tipc_net_finalize() in work queue context.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Konstantin has noticed that kvmalloc might trigger the following
warning:

  WARNING: CPU: 0 PID: 6676 at mm/vmstat.c:986 __fragmentation_index+0x54/0x60
  [...]
  Call Trace:
   fragmentation_index+0x76/0x90
   compaction_suitable+0x4f/0xf0
   shrink_node+0x295/0x310
   node_reclaim+0x205/0x250
   get_page_from_freelist+0x649/0xad0
   __alloc_pages_nodemask+0x12a/0x2a0
   kmalloc_large_node+0x47/0x90
   __kmalloc_node+0x22b/0x2e0
   kvmalloc_node+0x3e/0x70
   xt_alloc_table_info+0x3a/0x80 [x_tables]
   do_ip6t_set_ctl+0xcd/0x1c0 [ip6_tables]
   nf_setsockopt+0x44/0x60
   SyS_setsockopt+0x6f/0xc0
   do_syscall_64+0x67/0x120
   entry_SYSCALL_64_after_hwframe+0x3d/0xa2

the problem is that we only check for an out of bound order in the slow
path and the node reclaim might happen from the fast path already.  This
is fixable by making sure that kvmalloc doesn't ever use kmalloc for
requests that are larger than KMALLOC_MAX_SIZE but this also shows that
the code is rather fragile.  A recent UBSAN report just underlines that
by the following report

  UBSAN: Undefined behaviour in mm/page_alloc.c:3117:19
  shift exponent 51 is too large for 32-bit type 'int'
  CPU: 0 PID: 6520 Comm: syz-executor1 Not tainted 4.19.0-rc2 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
   __dump_stack lib/dump_stack.c:77 [inline]
   dump_stack+0xd2/0x148 lib/dump_stack.c:113
   ubsan_epilogue+0x12/0x94 lib/ubsan.c:159
   __ubsan_handle_shift_out_of_bounds+0x2b6/0x30b lib/ubsan.c:425
   __zone_watermark_ok+0x2c7/0x400 mm/page_alloc.c:3117
   zone_watermark_fast mm/page_alloc.c:3216 [inline]
   get_page_from_freelist+0xc49/0x44c0 mm/page_alloc.c:3300
   __alloc_pages_nodemask+0x21e/0x640 mm/page_alloc.c:4370
   alloc_pages_current+0xcc/0x210 mm/mempolicy.c:2093
   alloc_pages include/linux/gfp.h:509 [inline]
   __get_free_pages+0x12/0x60 mm/page_alloc.c:4414
   dma_mem_alloc+0x36/0x50 arch/x86/include/asm/floppy.h:156
   raw_cmd_copyin drivers/block/floppy.c:3159 [inline]
   raw_cmd_ioctl drivers/block/floppy.c:3206 [inline]
   fd_locked_ioctl+0xa00/0x2c10 drivers/block/floppy.c:3544
   fd_ioctl+0x40/0x60 drivers/block/floppy.c:3571
   __blkdev_driver_ioctl block/ioctl.c:303 [inline]
   blkdev_ioctl+0xb3c/0x1a30 block/ioctl.c:601
   block_ioctl+0x105/0x150 fs/block_dev.c:1883
   vfs_ioctl fs/ioctl.c:46 [inline]
   do_vfs_ioctl+0x1c0/0x1150 fs/ioctl.c:687
   ksys_ioctl+0x9e/0xb0 fs/ioctl.c:702
   __do_sys_ioctl fs/ioctl.c:709 [inline]
   __se_sys_ioctl fs/ioctl.c:707 [inline]
   __x64_sys_ioctl+0x7e/0xc0 fs/ioctl.c:707
   do_syscall_64+0xc4/0x510 arch/x86/entry/common.c:290
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Note that this is not a kvmalloc path.  It is just that the fast path
really depends on having sanitzed order as well.  Therefore move the
order check to the fast path.

Link: http://lkml.kernel.org/r/20181113094305.GM15120@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Byoungyoung Lee <lifeasageek@gmail.com>
Cc: "Dae R. Jeong" <threeearcat@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The current Cadence QSPI driver caused a kernel panic sporadically
when writing to QSPI. The problem was caused by writing more bytes
than needed because the QSPI operated on 4 bytes at a time.
<snip>
[   11.202044] Unable to handle kernel paging request at virtual address bffd3000
[   11.209254] pgd = e463054d
[   11.211948] [bffd3000] *pgd=2fffb811, *pte=00000000, *ppte=00000000
[   11.218202] Internal error: Oops: 7 [#1] SMP ARM
[   11.222797] Modules linked in:
[   11.225844] CPU: 1 PID: 1317 Comm: systemd-hwdb Not tainted 4.17.7-d0c45cd44a8f
[   11.235796] Hardware name: Altera SOCFPGA Arria10
[   11.240487] PC is at __raw_writesl+0x70/0xd4
[   11.244741] LR is at cqspi_write+0x1a0/0x2cc
</snip>
On a page boundary limit the number of bytes copied from the tx buffer
to remain within the page.

This patch uses a temporary buffer to hold the 4 bytes to write and then
copies only the bytes required from the tx buffer.

Reported-by: Adrian Amborzewicz <adrian.ambrozewicz@intel.com>
Signed-off-by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>