linux/drivers
Linus Torvalds 97d052ea3f A set of locking fixes and updates:
- Untangle the header spaghetti which causes build failures in various
     situations caused by the lockdep additions to seqcount to validate that
     the write side critical sections are non-preemptible.
 
   - The seqcount associated lock debug addons which were blocked by the
     above fallout.
 
     seqcount writers contrary to seqlock writers must be externally
     serialized, which usually happens via locking - except for strict per
     CPU seqcounts. As the lock is not part of the seqcount, lockdep cannot
     validate that the lock is held.
 
     This new debug mechanism adds the concept of associated locks.
     sequence count has now lock type variants and corresponding
     initializers which take a pointer to the associated lock used for
     writer serialization. If lockdep is enabled the pointer is stored and
     write_seqcount_begin() has a lockdep assertion to validate that the
     lock is held.
 
     Aside of the type and the initializer no other code changes are
     required at the seqcount usage sites. The rest of the seqcount API is
     unchanged and determines the type at compile time with the help of
     _Generic which is possible now that the minimal GCC version has been
     moved up.
 
     Adding this lockdep coverage unearthed a handful of seqcount bugs which
     have been addressed already independent of this.
 
     While generaly useful this comes with a Trojan Horse twist: On RT
     kernels the write side critical section can become preemtible if the
     writers are serialized by an associated lock, which leads to the well
     known reader preempts writer livelock. RT prevents this by storing the
     associated lock pointer independent of lockdep in the seqcount and
     changing the reader side to block on the lock when a reader detects
     that a writer is in the write side critical section.
 
  - Conversion of seqcount usage sites to associated types and initializers.
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Merge tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Thomas Gleixner:
 "A set of locking fixes and updates:

   - Untangle the header spaghetti which causes build failures in
     various situations caused by the lockdep additions to seqcount to
     validate that the write side critical sections are non-preemptible.

   - The seqcount associated lock debug addons which were blocked by the
     above fallout.

     seqcount writers contrary to seqlock writers must be externally
     serialized, which usually happens via locking - except for strict
     per CPU seqcounts. As the lock is not part of the seqcount, lockdep
     cannot validate that the lock is held.

     This new debug mechanism adds the concept of associated locks.
     sequence count has now lock type variants and corresponding
     initializers which take a pointer to the associated lock used for
     writer serialization. If lockdep is enabled the pointer is stored
     and write_seqcount_begin() has a lockdep assertion to validate that
     the lock is held.

     Aside of the type and the initializer no other code changes are
     required at the seqcount usage sites. The rest of the seqcount API
     is unchanged and determines the type at compile time with the help
     of _Generic which is possible now that the minimal GCC version has
     been moved up.

     Adding this lockdep coverage unearthed a handful of seqcount bugs
     which have been addressed already independent of this.

     While generally useful this comes with a Trojan Horse twist: On RT
     kernels the write side critical section can become preemtible if
     the writers are serialized by an associated lock, which leads to
     the well known reader preempts writer livelock. RT prevents this by
     storing the associated lock pointer independent of lockdep in the
     seqcount and changing the reader side to block on the lock when a
     reader detects that a writer is in the write side critical section.

   - Conversion of seqcount usage sites to associated types and
     initializers"

* tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  locking/seqlock, headers: Untangle the spaghetti monster
  locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header
  x86/headers: Remove APIC headers from <asm/smp.h>
  seqcount: More consistent seqprop names
  seqcount: Compress SEQCNT_LOCKNAME_ZERO()
  seqlock: Fold seqcount_LOCKNAME_init() definition
  seqlock: Fold seqcount_LOCKNAME_t definition
  seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g
  hrtimer: Use sequence counter with associated raw spinlock
  kvm/eventfd: Use sequence counter with associated spinlock
  userfaultfd: Use sequence counter with associated spinlock
  NFSv4: Use sequence counter with associated spinlock
  iocost: Use sequence counter with associated spinlock
  raid5: Use sequence counter with associated spinlock
  vfs: Use sequence counter with associated spinlock
  timekeeping: Use sequence counter with associated raw spinlock
  xfrm: policy: Use sequence counters with associated lock
  netfilter: nft_set_rbtree: Use sequence counter with associated rwlock
  netfilter: conntrack: Use sequence counter with associated spinlock
  sched: tasks: Use sequence counter with associated spinlock
  ...
2020-08-10 19:07:44 -07:00
..
accessibility TTY/Serial patches for 5.9-rc1 2020-08-06 14:56:11 -07:00
acpi - Add support to enable/disable the thermal zones resulting on core code and 2020-08-06 18:10:55 -07:00
amba
android drivers: android: Fix the SPDX comment style 2020-07-29 17:05:44 +02:00
ata
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
auxdisplay Minor cleanup for auxdisplay: 2020-08-06 18:09:34 -07:00
base More power management updates for 5.9-rc1 2020-08-07 13:13:09 -07:00
bcma bcma: gpio: Use irqchip template 2020-08-02 18:26:51 +03:00
block pci-v5.9-changes 2020-08-07 18:48:15 -07:00
bluetooth Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next 2020-07-31 15:11:52 -07:00
bus MIPS upates for v5.9 2020-08-06 10:54:07 -07:00
cdrom
char Minor cleanups to the IPMI driver for 5.9 2020-08-08 09:32:18 -07:00
clk It looks like a smaller batch of clk updates this time around. In the core 2020-08-07 13:35:51 -07:00
clocksource Time, timers and related driver updates: 2020-08-04 18:17:37 -07:00
connector
counter Merge branch 'ib-5.8-tcb' into HEAD 2020-07-22 14:37:23 +01:00
cpufreq Merge branch 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm 2020-08-04 12:44:53 +02:00
cpuidle powerpc updates for 5.9 2020-08-07 10:33:50 -07:00
crypto Merge branch 'akpm' (patches from Andrew) 2020-08-07 11:39:33 -07:00
dax
dca
devfreq PM / devfreq: Fix the wrong end with semicolon 2020-07-30 17:22:58 +09:00
dio
dma Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 21:14:30 -07:00
dma-buf A set of locking fixes and updates: 2020-08-10 19:07:44 -07:00
edac 17ed808ad2 ("EDAC: Fix reference count leaks") 2020-08-03 20:01:00 -07:00
eisa
extcon
firewire
firmware Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
fpga Linux 5.8-rc7 2020-07-27 11:49:37 +02:00
fsi
gnss
gpio This is the bulk of GPIO changes for the v5.9 kernel cycle: 2020-08-05 12:56:27 -07:00
gpu A set of locking fixes and updates: 2020-08-10 19:07:44 -07:00
greybus greybus: Use fallthrough pseudo-keyword 2020-07-29 16:58:08 +02:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2020-08-10 16:33:54 -07:00
hsi
hv hyperv-next for 5.9 2020-08-06 09:26:10 -07:00
hwmon hwmon updates for v5.9 2020-08-05 13:13:57 -07:00
hwspinlock
hwtracing
i2c Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
i3c
ide
idle Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
iio iio: imu: st_lsm6dsx: reset hw ts after resume 2020-07-22 14:55:43 +01:00
infiniband RDMA 5.9 merge window pull request 2020-08-06 16:43:36 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2020-08-10 16:35:57 -07:00
interconnect Char/Misc driver patches for 5.9-rc1 2020-08-05 11:43:47 -07:00
iommu A set of locking fixes and updates: 2020-08-10 19:07:44 -07:00
ipack
irqchip The usual boring updates from the interrupt subsystem: 2020-08-04 18:11:58 -07:00
isdn mISDN: Don't try to print a sockptr_t from debug logging code. 2020-07-24 16:36:13 -07:00
leds LEDs changes for 5.9-rc1. 2020-08-05 19:24:27 -07:00
lightnvm
macintosh powerpc updates for 5.9 2020-08-07 10:33:50 -07:00
mailbox mailbox: mediatek: cmdq: clear task in channel before shutdown 2020-08-03 23:56:38 -05:00
mcb
md A set of locking fixes and updates: 2020-08-10 19:07:44 -07:00
media pci-v5.9-changes 2020-08-07 18:48:15 -07:00
memory MTD core changes: 2020-08-09 12:38:51 -07:00
memstick MMC core: 2020-08-05 13:23:24 -07:00
message
mfd irqdomain/treewide: Free firmware node after domain removal 2020-07-23 00:08:52 +02:00
misc Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 21:14:30 -07:00
mmc This tree adds the sched_set_fifo*() encapsulation APIs to remove 2020-08-06 11:55:43 -07:00
most drivers: most: add USB adapter driver 2020-07-31 14:38:12 +02:00
mtd This pull request contains changes for JFFS2, UBI and UBIFS 2020-08-10 18:20:04 -07:00
mux
net pci-v5.9-changes 2020-08-07 18:48:15 -07:00
nfc
ntb
nubus
nvdimm powerpc updates for 5.9 2020-08-07 10:33:50 -07:00
nvme for-5.9/block-merge-20200804 2020-08-05 11:12:34 -07:00
nvmem nvmem: qcom-spmi-sdam: Enable multiple devices 2020-07-29 17:12:09 +02:00
of MIPS upates for v5.9 2020-08-06 10:54:07 -07:00
opp Merge branch 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm 2020-08-04 12:44:53 +02:00
oprofile
parisc
parport
pci pci-v5.9-changes 2020-08-07 18:48:15 -07:00
pcmcia
perf It looks like a smaller batch of clk updates this time around. In the core 2020-08-07 13:35:51 -07:00
phy phy for 5.9 2020-07-23 09:52:10 +02:00
pinctrl This is the bulk of the pin control changes for the v5.9 2020-08-09 12:52:28 -07:00
platform - Add support to enable/disable the thermal zones resulting on core code and 2020-08-06 18:10:55 -07:00
pnp
power power supply and reset changes for the v5.9 series 2020-08-07 21:27:37 -07:00
powercap This tree adds the sched_set_fifo*() encapsulation APIs to remove 2020-08-06 11:55:43 -07:00
pps
ps3
ptp ptp: only allow phase values lower than 1 period 2020-08-05 12:06:44 -07:00
pwm
rapidio
ras
regulator Merge remote-tracking branch 'regulator/for-5.9' into regulator-next 2020-07-30 23:27:08 +01:00
remoteproc
reset SOC: TI Keystone driver update for v5.9 2020-07-27 14:24:51 +02:00
rpmsg
rtc
s390 Merge branch 'akpm' (patches from Andrew) 2020-08-07 11:39:33 -07:00
sbus
scsi pci-v5.9-changes 2020-08-07 18:48:15 -07:00
sfi
sh
siox
slimbus
soc Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 21:14:30 -07:00
soundwire soundwire updates for 5.9-rc1 2020-07-23 09:12:15 +02:00
spi sound updates for 5.9 2020-08-06 14:27:31 -07:00
spmi
ssb Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
staging pci-v5.9-changes 2020-08-07 18:48:15 -07:00
target Merge branch 'akpm' (patches from Andrew) 2020-08-07 11:39:33 -07:00
tc
tee
thermal thermal: don't make THERMAL_NETLINK 'default y' 2020-08-07 09:05:02 -07:00
thunderbolt thunderbolt: merge fix for kunix_resource changes 2020-08-09 11:06:10 -07:00
tty TTY/Serial patches for 5.9-rc1 2020-08-06 14:56:11 -07:00
uio
usb media updates for v5.9-rc1 2020-08-07 13:00:53 -07:00
vdpa
vfio
vhost Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
video TTY/Serial patches for 5.9-rc1 2020-08-06 14:56:11 -07:00
virt
virtio Remove uninitialized_var() macro for v5.9-rc1 2020-08-04 13:49:43 -07:00
visorbus
vlynq
vme
w1
watchdog
xen Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
zorro
Kconfig
Makefile