The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: rcu@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The WARN_ON_ONCE() invocation within the CONFIG_PREEMPT=y version of
rcu_note_context_switch() triggers when there is a voluntary context
switch in an RCU read-side critical section, but there is quite a gap
between the output of that WARN_ON_ONCE() and this RCU-usage error.
This commit therefore converts the WARN_ON_ONCE() to a WARN_ONCE()
that explicitly describes the problem in its message.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The cond_resched() function reports an RCU quiescent state only in
non-preemptible TREE RCU implementation.  This commit therefore adds a
comment explaining why cond_resched() does nothing in preemptible kernels.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Neeraj Upadhyay <neeraju@codeaurora.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Uladzislau Rezki <urezki@gmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

There are a few remaining locations in kernel/rcu that still use
"&per_cpu()".  This commit replaces them with "per_cpu_ptr(&)", and does
not introduce any functional change.
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Within rcu_gp_fqs_loop(), the "ret" local variable is set to the
return value from swait_event_idle_timeout_exclusive(), but "ret" is
unconditionally overwritten later in the code.  This commit therefore
removes this useless assignment.
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

This commit marks the accesses in tree_stall.h so as to both avoid
undesirable compiler optimizations and to keep KCSAN focused on the
accesses of the core algorithm.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The kbuild test project found an oversized stack frame in rcu_gp_kthread()
for some kernel configurations.  This oversizing was due to a very large
amount of inlining, which is unnecessary due to the fact that this code
executes infrequently.  This commit therefore marks rcu_gp_init() and
rcu_gp_fqs_loop noinline_for_stack to conserve stack space.
Reported-by: kernel test robot <lkp@intel.com>
Tested-by: Rong Chen <rong.a.chen@intel.com>
[ paulmck: noinline_for_stack per Nathan Chancellor. ]
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Accesses to ->qsmask are normally protected by ->lock, but there is an
exception in the diagnostic code in rcu_check_boost_fail().  This commit
therefore applies data_race() to this access to avoid KCSAN complaining
about the C-language writes protected by ->lock.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

This commit marks some interrupt-induced read-side data races in
__srcu_read_lock(), __srcu_read_unlock(), and srcu_torture_stats_print().
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Systems with low-bandwidth consoles can have very large printk()
latencies, and on such systems it makes no sense to have the next RCU CPU
stall warning message start output before the prior message completed.
This commit therefore sets the time of the next stall only after the
prints have completed.  While printing, the time of the next stall
message is set to ULONG_MAX/2 jiffies into the future.
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

rcu_cpu_stall_reset() is one of the functions virtual CPUs
execute during VM resume in order to handle jiffies skew
that can trigger false positive stall warnings. Paul has
pointed out that this approach is problematic because
rcu_cpu_stall_reset() disables RCU grace period stall-detection
virtually forever, while in fact it can just restart the
stall-detection timeout.
Suggested-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The soft watchdog timer function checks if a virtual machine
was suspended and hence what looks like a lockup in fact
is a false positive.

This is what kvm_check_and_clear_guest_paused() does: it
tests guest PVCLOCK_GUEST_STOPPED (which is set by the host)
and if it's set then we need to touch all watchdogs and bail
out.

Watchdog timer function runs from IRQ, so PVCLOCK_GUEST_STOPPED
check works fine.

There is, however, one more watchdog that runs from IRQ, so
watchdog timer fn races with it, and that watchdog is not aware
of PVCLOCK_GUEST_STOPPED - RCU stall detector.

apic_timer_interrupt()
 smp_apic_timer_interrupt()
  hrtimer_interrupt()
   __hrtimer_run_queues()
    tick_sched_timer()
     tick_sched_handle()
      update_process_times()
       rcu_sched_clock_irq()

This triggers RCU stalls on our devices during VM resume.

If tick_sched_handle()->rcu_sched_clock_irq() runs on a VCPU
before watchdog_timer_fn()->kvm_check_and_clear_guest_paused()
then there is nothing on this VCPU that touches watchdogs and
RCU reads stale gp stall timestamp and new jiffies value, which
makes it think that RCU has stalled.

Make RCU stall watchdog aware of PVCLOCK_GUEST_STOPPED and
don't report RCU stalls when we resume the VM.
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

We have two separate sections that talk about why list_empty_rcu()
is not needed, so this commit consolidates them.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
[ paulmck: The usual wordsmithing. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

KCSAN flags accesses to ->rcu_read_lock_nesting as data races, but
in the past, the overhead of marked accesses was excessive.  However,
that was long ago, and much has changed since then, both in terms of
hardware and of compilers.  Here is data taken on an eight-core laptop
using Intel(R) Core(TM) i9-10885H CPU @ 2.40GHz with a kernel built
using gcc version 9.3.0, with all data in nanoseconds.

Unmarked accesses (status quo), measured by three refscale runs:

	Minimum reader duration:  3.286  2.851  3.395
	Median reader duration:   3.698  3.531  3.4695
	Maximum reader duration:  4.481  5.215  5.157

Marked accesses, also measured by three refscale runs:

	Minimum reader duration:  3.501  3.677  3.580
	Median reader duration:   4.053  3.723  3.895
	Maximum reader duration:  7.307  4.999  5.511

This focused microbenhmark shows only sub-nanosecond differences which
are unlikely to be visible at the system level.  This commit therefore
marks data-racing accesses to ->rcu_read_lock_nesting.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Accesses to the rcu_data structure's ->dynticks field have always been
fully ordered because it was not possible to prove that weaker ordering
was safe.  However, with the removal of the rcu_eqs_special_set() function
and the advent of the Linux-kernel memory model, it is now easy to show
that two of the four original full memory barriers can be weakened to
acquire and release operations.  The remaining pair must remain full
memory barriers.  This change makes the memory ordering requirements
more evident, and it might well also speed up the to-idle and from-idle
fastpaths on some architectures.

The following litmus test, adapted from one supplied off-list by Frederic
Weisbecker, models the RCU grace-period kthread detecting an idle CPU
that is concurrently transitioning to non-idle:

	C dynticks-from-idle

	{
		DYNTICKS=0; (* Initially idle. *)
	}

	P0(int *X, int *DYNTICKS)
	{
		int dynticks;
		int x;

		// Idle.
		dynticks = READ_ONCE(*DYNTICKS);
		smp_store_release(DYNTICKS, dynticks + 1);
		smp_mb();
		// Now non-idle
		x = READ_ONCE(*X);
	}

	P1(int *X, int *DYNTICKS)
	{
		int dynticks;

		WRITE_ONCE(*X, 1);
		smp_mb();
		dynticks = smp_load_acquire(DYNTICKS);
	}

	exists (1:dynticks=0 /\ 0:x=1)

Running "herd7 -conf linux-kernel.cfg dynticks-from-idle.litmus" verifies
this transition, namely, showing that if the RCU grace-period kthread (P1)
sees another CPU as idle (P0), then any memory access prior to the start
of the grace period (P1's write to X) will be seen by any RCU read-side
critical section following the to-non-idle transition (P0's read from X).
This is a straightforward use of full memory barriers to force ordering
in a store-buffering (SB) litmus test.

The following litmus test, also adapted from the one supplied off-list
by Frederic Weisbecker, models the RCU grace-period kthread detecting
a non-idle CPU that is concurrently transitioning to idle:

	C dynticks-into-idle

	{
		DYNTICKS=1; (* Initially non-idle. *)
	}

	P0(int *X, int *DYNTICKS)
	{
		int dynticks;

		// Non-idle.
		WRITE_ONCE(*X, 1);
		dynticks = READ_ONCE(*DYNTICKS);
		smp_store_release(DYNTICKS, dynticks + 1);
		smp_mb();
		// Now idle.
	}

	P1(int *X, int *DYNTICKS)
	{
		int x;
		int dynticks;

		smp_mb();
		dynticks = smp_load_acquire(DYNTICKS);
		x = READ_ONCE(*X);
	}

	exists (1:dynticks=2 /\ 1:x=0)

Running "herd7 -conf linux-kernel.cfg dynticks-into-idle.litmus" verifies
this transition, namely, showing that if the RCU grace-period kthread
(P1) sees another CPU as newly idle (P0), then any pre-idle memory access
(P0's write to X) will be seen by any code following the grace period
(P1's read from X).  This is a simple release-acquire pair forcing
ordering in a message-passing (MP) litmus test.

Of course, if the grace-period kthread detects the CPU as non-idle,
it will refrain from reporting a quiescent state on behalf of that CPU,
so there are no ordering requirements from the grace-period kthread in
that case.  However, other subsystems call rcu_is_idle_cpu() to check
for CPUs being non-idle from an RCU perspective.  That case is also
verified by the above litmus tests with the proviso that the sense of
the low-order bit of the DYNTICKS counter be inverted.

Unfortunately, on x86 smp_mb() is as expensive as a cache-local atomic
increment.  This commit therefore weakens only the read from ->dynticks.
However, the updates are abstracted into a rcu_dynticks_inc() function
to ease any future changes that might be needed.

[ paulmck: Apply Linus Torvalds feedback. ]

Link: https://lore.kernel.org/lkml/20210721202127.2129660-4-paulmck@kernel.org/Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Commit b8c17e66 ("rcu: Maintain special bits at bottom of ->dynticks
counter") reserved a bit at the bottom of the ->dynticks counter to defer
flushing of TLBs, but this facility never has been used.  This commit
therefore removes this capability along with the rcu_eqs_special_set()
function used to trigger it.

Link: https://lore.kernel.org/linux-doc/CALCETrWNPOOdTrFabTDd=H7+wc6xJ9rJceg6OL1S0rTV5pfSsA@mail.gmail.com/Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: "Joel Fernandes (Google)" <joel@joelfernandes.org>
[ paulmck: Forward-port to v5.13-rc1. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

If rcu_print_task_stall() is invoked on an rcu_node structure that does
not contain any tasks blocking the current grace period, it takes an
early exit that fails to release that rcu_node structure's lock.  This
results in a self-deadlock, which is detected by lockdep.

To reproduce this bug:

tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --duration 3 --trust-make --configs "TREE03" --kconfig "CONFIG_PROVE_LOCKING=y" --bootargs "rcutorture.stall_cpu=30 rcutorture.stall_cpu_block=1 rcutorture.fwd_progress=0 rcutorture.test_boost=0"

This will also result in other complaints, including RCU's scheduler
hook complaining about blocking rather than preemption and an rcutorture
writer stall.

Only a partial RCU CPU stall warning message will be printed because of
the self-deadlock.

This commit therefore releases the lock on the rcu_print_task_stall()
function's early exit path.

Fixes: c583bcb8 ("rcu: Don't invoke try_invoke_on_locked_down_task() with irqs disabled")
Tested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The for loop in rcu_print_task_stall() always omits ts[0], which points
to the first task blocking the stalled grace period.  This in turn fails
to count this first task, which means that ndetected will be equal to
zero when all CPUs have passed through their quiescent states and only
one task is blocking the stalled grace period.  This zero value for
ndetected will in turn result in an incorrect "All QSes seen" message:

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu:    Tasks blocked on level-1 rcu_node (CPUs 12-23):
        (detected by 15, t=6504 jiffies, g=164777, q=9011209)
rcu: All QSes seen, last rcu_preempt kthread activity 1 (4295252379-4295252378), jiffies_till_next_fqs=1, root ->qsmask 0x2
BUG: sleeping function called from invalid context at include/linux/uaccess.h:156
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 70613, name: msgstress04
INFO: lockdep is turned off.
Preemption disabled at:
[<ffff8000104031a4>] create_object.isra.0+0x204/0x4b0
CPU: 15 PID: 70613 Comm: msgstress04 Kdump: loaded Not tainted
5.12.2-yoctodev-standard #1
Hardware name: Marvell OcteonTX CN96XX board (DT)
Call trace:
 dump_backtrace+0x0/0x2cc
 show_stack+0x24/0x30
 dump_stack+0x110/0x188
 ___might_sleep+0x214/0x2d0
 __might_sleep+0x7c/0xe0

This commit therefore fixes the loop to include ts[0].

Fixes: c583bcb8 ("rcu: Don't invoke try_invoke_on_locked_down_task() with irqs disabled")
Tested-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Merge tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Skip invalid hybrid PMU on hybrid systems when the atom (little) CPUs
   are offlined.

 - Fix 'perf test' problems related to the recently added hybrid
   (BIG/little) code.

 - Split ARM's coresight (hw tracing) decode by aux records to avoid
   fatal decoding errors.

 - Fix add event failure in 'perf probe' when running 32-bit perf in a
   64-bit kernel.

 - Fix 'perf sched record' failure when CONFIG_SCHEDSTATS is not set.

 - Fix memory and refcount leaks detected by ASAn when running 'perf
   test', should be clean of warnings now.

 - Remove broken definition of __LITTLE_ENDIAN from tools'
   linux/kconfig.h, which was breaking the build in some systems.

 - Cast PTHREAD_STACK_MIN to int as it may turn into 'long
   sysconf(__SC_THREAD_STACK_MIN_VALUE), breaking the build in some
   systems.

 - Fix libperf build error with LIBPFM4=1.

 - Sync UAPI files changed by the memfd_secret new syscall.

* tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (35 commits)
  perf sched: Fix record failure when CONFIG_SCHEDSTATS is not set
  perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
  perf data: Close all files in close_dir()
  perf probe-file: Delete namelist in del_events() on the error path
  perf test bpf: Free obj_buf
  perf trace: Free strings in trace__parse_events_option()
  perf trace: Free syscall tp fields in evsel->priv
  perf trace: Free syscall->arg_fmt
  perf trace: Free malloc'd trace fields on exit
  perf lzma: Close lzma stream on exit
  perf script: Fix memory 'threads' and 'cpus' leaks on exit
  perf script: Release zstd data
  perf session: Cleanup trace_event
  perf inject: Close inject.output on exit
  perf report: Free generated help strings for sort option
  perf env: Fix memory leak of cpu_pmu_caps
  perf test maps__merge_in: Fix memory leak of maps
  perf dso: Fix memory leak in dso__new_map()
  perf test event_update: Fix memory leak of unit
  perf test event_update: Fix memory leak of evlist
  ...

Pull xfs fixes from Darrick Wong:
 "A few fixes for issues in the new online shrink code, additional
  corrections for my recent bug-hunt w.r.t. extent size hints on
  realtime, and improved input checking of the GROWFSRT ioctl.

  IOW, the usual 'I somehow got bored during the merge window and
  resumed auditing the farther reaches of xfs':

   - Fix shrink eligibility checking when sparse inode clusters enabled

   - Reset '..' directory entries when unlinking directories to prevent
     verifier errors if fs is shrinked later

   - Don't report unusable extent size hints to FSGETXATTR

   - Don't warn when extent size hints are unusable because the sysadmin
     configured them that way

   - Fix insufficient parameter validation in GROWFSRT ioctl

   - Fix integer overflow when adding rt volumes to filesystem"

* tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: detect misaligned rtinherit directory extent size hints
  xfs: fix an integer overflow error in xfs_growfs_rt
  xfs: improve FSGROWFSRT precondition checking
  xfs: don't expose misaligned extszinherit hints to userspace
  xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
  xfs: reset child dir '..' entry when unlinking child
  xfs: check for sparse inode clusters that cross new EOAG when shrinking

Pull iomap fixes from Darrick Wong:
 "A handful of bugfixes for the iomap code.

  There's nothing especially exciting here, just fixes for UBSAN (not
  KASAN as I erroneously wrote in the tag message) warnings about
  undefined behavior in the SEEK_DATA/SEEK_HOLE code, and some
  reshuffling of per-page block state info to fix some problems with
  gfs2.

   - Fix KASAN warnings due to integer overflow in SEEK_DATA/SEEK_HOLE

   - Fix assertion errors when using inlinedata files on gfs2"

* tag 'iomap-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: Don't create iomap_page objects in iomap_page_mkwrite_actor
  iomap: Don't create iomap_page objects for inline files
  iomap: Permit pages without an iop to enter writeback
  iomap: remove the length variable in iomap_seek_hole
  iomap: remove the length variable in iomap_seek_data

Merge tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Restore the original behavior of scripts/setlocalversion when
   LOCALVERSION is set to empty.

 - Show Kconfig prompts even for 'make -s'

 - Fix the combination of COFNIG_LTO_CLANG=y and CONFIG_MODVERSIONS=y
   for older GNU Make versions

* tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  Documentation: Fix intiramfs script name
  Kbuild: lto: fix module versionings mismatch in GNU make 3.X
  kbuild: do not suppress Kconfig prompts for silent build
  scripts/setlocalversion: fix a bug when LOCALVERSION is empty

Documentation was not changed when renaming the script in commit
80e715a0 ("initramfs: rename gen_initramfs_list.sh to
gen_initramfs.sh"). Fixing this.

Basically does:

 $ sed -i -e s/gen_initramfs_list.sh/gen_initramfs.sh/g $(git grep -l gen_initramfs_list.sh)

Fixes: 80e715a0 ("initramfs: rename gen_initramfs_list.sh to gen_initramfs.sh")
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When building modules(CONFIG_...=m), I found some of module versions
are incorrect and set to 0.
This can be found in build log for first clean build which shows

WARNING: EXPORT symbol "XXXX" [drivers/XXX/XXX.ko] version generation failed,
symbol will not be versioned.

But in second build(incremental build), the WARNING disappeared and the
module version becomes valid CRC and make someone who want to change
modules without updating kernel image can't insert their modules.

The problematic code is
+	$(foreach n, $(filter-out FORCE,$^),				\
+		$(if $(wildcard $(n).symversions),			\
+			; cat $(n).symversions >> $@.symversions))

For example:
  rm -f fs/notify/built-in.a.symversions    ; rm -f fs/notify/built-in.a; \
llvm-ar cDPrST fs/notify/built-in.a fs/notify/fsnotify.o \
fs/notify/notification.o fs/notify/group.o ...

`foreach n` shows nothing to `cat` into $(n).symversions because
`if $(wildcard $(n).symversions)` return nothing, but actually
they do exist during this line was executed.

-rw-r--r-- 1 root root 168580 Jun 13 19:10 fs/notify/fsnotify.o
-rw-r--r-- 1 root root    111 Jun 13 19:10 fs/notify/fsnotify.o.symversions

The reason is the $(n).symversions are generated at runtime, but
Makefile wildcard function expends and checks the file exist or not
during parsing the Makefile.

Thus fix this by use `test` shell command to check the file
existence in runtime.

Rebase from both:
1. [https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@mediatek.com/]
2. [https://lore.kernel.org/lkml/20210702032943.7865-1-lecopzer.chen@mediatek.com/]

Fixes: 38e89184 ("kbuild: lto: fix module versioning")
Co-developed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When a new CONFIG option is available, Kbuild shows a prompt to get
the user input.

  $ make
  [ snip ]
  Core Scheduling for SMT (SCHED_CORE) [N/y/?] (NEW)

This is the only interactive place in the build process.

Commit 174a1dcc ("kbuild: sink stdout from cmd for silent build")
suppressed Kconfig prompts as well because syncconfig is invoked by
the 'cmd' macro. You cannot notice the fact that Kconfig is waiting
for the user input.

Use 'kecho' to show the equivalent short log without suppressing stdout
from sub-make.

Fixes: 174a1dcc ("kbuild: sink stdout from cmd for silent build")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

The commit 042da426 ("scripts/setlocalversion: simplify the short
version part") reduces indentation. Unfortunately, it also changes behavior
in a subtle way - if the user has empty "LOCALVERSION" variable, the plus
sign is appended to the kernel version. It wasn't appended before.

This patch reverts to the old behavior - we append the plus sign only if
the LOCALVERSION variable is not set.

Fixes: 042da426 ("scripts/setlocalversion: simplify the short version part")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The tracepoints trace_sched_stat_{wait, sleep, iowait} are not exposed to user
if CONFIG_SCHEDSTATS is not set, "perf sched record" records the three events.
As a result, the command fails.

Before:

  #perf sched record sleep 1
  event syntax error: 'sched:sched_stat_wait'
                       \___ unknown tracepoint

  Error:  File /sys/kernel/tracing/events/sched/sched_stat_wait not found.
  Hint:   Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events

Solution:
  Check whether schedstat tracepoints are exposed. If no, these events are not recorded.

After:
  # perf sched record sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.163 MB perf.data (1091 samples) ]
  # perf sched report
  run measurement overhead: 4736 nsecs
  sleep measurement overhead: 9059979 nsecs
  the run test took 999854 nsecs
  the sleep test took 8945271 nsecs
  nr_run_events:        716
  nr_sleep_events:      785
  nr_wakeup_events:     0
  ...
  ------------------------------------------------------------

Fixes: 2a09b5de ("sched/fair: do not expose some tracepoints to user if CONFIG_SCHEDSTATS is not set")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Yafang Shao <laoar.shao@gmail.com>
Link: http://lore.kernel.org/lkml/20210713112358.194693-1-yangjihong1@huawei.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The "address" member of "struct probe_trace_point" uses long data type.
If kernel is 64-bit and perf program is 32-bit, size of "address"
variable is 32 bits.

As a result, upper 32 bits of address read from kernel are truncated, an
error occurs during address comparison in kprobe_warn_out_range().

Before:

  # perf probe -a schedule
  schedule is out of .text, skip it.
    Error: Failed to add events.

Solution:
  Change data type of "address" variable to u64 and change corresponding
address printing and value assignment.

After:

  # perf.new.new probe -a schedule
  Added new event:
    probe:schedule       (on schedule)

  You can now use it in all perf tools, such as:

          perf record -e probe:schedule -aR sleep 1

  # perf probe -l
    probe:schedule       (on schedule@kernel/sched/core.c)
  # perf record -e probe:schedule -aR sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
  # perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'probe:schedule'
  # Event count (approx.): 1366
  #
  # Overhead  Command          Shared Object      Symbol
  # ........  ...............  .................  ............
  #
       6.22%  migration/0      [kernel.kallsyms]  [k] schedule
       6.22%  migration/1      [kernel.kallsyms]  [k] schedule
       6.22%  migration/2      [kernel.kallsyms]  [k] schedule
       6.22%  migration/3      [kernel.kallsyms]  [k] schedule
       6.15%  migration/10     [kernel.kallsyms]  [k] schedule
       6.15%  migration/11     [kernel.kallsyms]  [k] schedule
       6.15%  migration/12     [kernel.kallsyms]  [k] schedule
       6.15%  migration/13     [kernel.kallsyms]  [k] schedule
       6.15%  migration/14     [kernel.kallsyms]  [k] schedule
       6.15%  migration/15     [kernel.kallsyms]  [k] schedule
       6.15%  migration/4      [kernel.kallsyms]  [k] schedule
       6.15%  migration/5      [kernel.kallsyms]  [k] schedule
       6.15%  migration/6      [kernel.kallsyms]  [k] schedule
       6.15%  migration/7      [kernel.kallsyms]  [k] schedule
       6.15%  migration/8      [kernel.kallsyms]  [k] schedule
       6.15%  migration/9      [kernel.kallsyms]  [k] schedule
       0.22%  rcu_sched        [kernel.kallsyms]  [k] schedule
  ...
  #
  # (Cannot load tips.txt file, please install perf!)
  #
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jianlin Lv <jianlin.lv@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When using 'perf report' in directory mode, the first file is not closed
on exit, causing a memory leak.

The problem is caused by the iterating variable never reaching 0.

Fixes: 14552063 ("perf data: Add perf_data__(create_dir|close_dir) functions")
Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Link: http://lore.kernel.org/lkml/20210716141122.858082-1-rickyman7@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

ASan reports some memory leaks when running:

  # perf test "42: BPF filter"

This second leak is caused by a strlist not being dellocated on error
inside probe_file__del_events.

This patch adds a goto label before the deallocation and makes the error
path jump to it.
Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Fixes: e7895e42 ("perf probe: Split del_perf_probe_events()")
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/174963c587ae77fa108af794669998e4ae558338.1626343282.git.rickyman7@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull ARM SoC fixes from Arnd Bergmann:
 "Here are the patches for this week that came as the fallout of the
  merge window:

   - Two fixes for the NVidia memory controller driver

   - multiple defconfig files get patched to turn CONFIG_FB back on
     after that is no longer selected by CONFIG_DRM

   - ffa and scmpi firmware drivers fixes, mostly addressing compiler
     and documentation warnings

   - Platform specific fixes for device tree files on ASpeed, Renesas
     and NVidia SoC, mostly for recent regressions.

   - A workaround for a regression on the USB PHY with devlink when the
     usb-nop-xceiv driver is not available until the rootfs is mounted.

   - Device tree compiler warnings in Arm Versatile-AB"

* tag 'soc-fixes-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (35 commits)
  ARM: dts: versatile: Fix up interrupt controller node names
  ARM: multi_v7_defconfig: Make NOP_USB_XCEIV driver built-in
  ARM: configs: Update u8500_defconfig
  ARM: configs: Update Vexpress defconfig
  ARM: configs: Update Versatile defconfig
  ARM: configs: Update RealView defconfig
  ARM: configs: Update Integrator defconfig
  arm: Typo s/PCI_IXP4XX_LEGACY/IXP4XX_PCI_LEGACY/
  firmware: arm_scmi: Fix range check for the maximum number of pending messages
  firmware: arm_scmi: Avoid padding in sensor message structure
  firmware: arm_scmi: Fix kernel doc warnings about return values
  firmware: arm_scpi: Fix kernel doc warnings
  firmware: arm_scmi: Fix kernel doc warnings
  ARM: shmobile: defconfig: Restore graphical consoles
  firmware: arm_ffa: Fix a possible ffa_linux_errmap buffer overflow
  firmware: arm_ffa: Fix the comment style
  firmware: arm_ffa: Simplify probe function
  firmware: arm_ffa: Ensure drivers provide a probe function
  firmware: arm_scmi: Fix possible scmi_linux_errmap buffer overflow
  firmware: arm_scmi: Ensure drivers provide a probe function
  ...

This reverts commit 78869146.

It's not clear why, but it causes unexplained problems in entirely
unrelated xfs code.  The most likely explanation is some slab
corruption, possibly triggered due to CONFIG_SLUB_DEBUG_ON.  See [1].

It ends up having a few other problems too, like build errors on
arch/arc, and Geert reporting it using much more memory on m68k [3] (it
probably does so elsewhere too, but it is probably just more noticeable
on m68k).

The architecture issues (both build and memory use) are likely just
because this change effectively force-enabled STACKDEPOT (along with a
very bad default value for the stackdepot hash size).  But together with
the xfs issue, this all smells like "this commit was not ready" to me.

Link: https://lore.kernel.org/linux-xfs/YPE3l82acwgI2OiV@infradead.org/ [1]
Link: https://lore.kernel.org/lkml/202107150600.LkGNb4Vb-lkp@intel.com/ [2]
Link: https://lore.kernel.org/lkml/CAMuHMdW=eoVzM1Re5FVoEN87nKfiLmM2+Ah7eNu2KXEhCvbZyA@mail.gmail.com/ [3]
Reported-by: Christoph Hellwig <hch@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull SCSI fixes from James Bottomley:
 "One core fix for an oops which can occur if the error handling thread
  fails to start for some reason and the driver is removed.

  The other fixes are all minor ones in drivers"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: core: Add missing host_lock in ufshcd_vops_setup_xfer_req()
  scsi: mpi3mr: Fix W=1 compilation warnings
  scsi: pm8001: Clean up kernel-doc and comments
  scsi: zfcp: Report port fc_security as unknown early during remote cable pull
  scsi: core: Fix bad pointer dereference when ehandler kthread is invalid
  scsi: fas216: Fix a build error
  scsi: core: Fix the documentation of the scsi_execute() time parameter

Pull cifs fixes from Steve French:
 "Eight cifs/smb3 fixes, including three for stable.

  Three are DFS related fixes, and two to fix problems pointed out by
  static checkers"

* tag '5.14-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: do not share tcp sessions of dfs connections
  SMB3.1.1: fix mount failure to some servers when compression enabled
  cifs: added WARN_ON for all the count decrements
  cifs: fix missing null session check in mount
  cifs: handle reconnect of tcon when there is no cached dfs referral
  cifs: fix the out of range assignment to bit fields in parse_server_interfaces
  cifs: Do not use the original cruid when following DFS links for multiuser mounts
  cifs: use the expiry output of dns_query to schedule next resolution

Merge tag 'linux-kselftest-kunit-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kunit fixes from Shuah Khan:
 "Fixes to kunit tool and documentation:

   - fix asserts on older python versions

   - fixes to misleading error messages when TAP header format is
     incorrect or when file is missing

   - documentation fix: drop obsolete information about uml_abort
     coverage

   - remove unnecessary annotations"

* tag 'linux-kselftest-kunit-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: tool: Assert the version requirement
  kunit: tool: remove unnecessary "annotations" import
  Documentation: kunit: drop obsolete note about uml_abort for coverage
  kunit: tool: Fix error messages for cases of no tests and wrong TAP header

Merge tag 'linux-kselftest-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kselftest fix from Shuah Khan:
 "A fix to memory-hotplug hot-remove test to stop spamming logs with
  dump_page() entries and slowing the system down to a crawl"

* tag 'linux-kselftest-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: memory-hotplug: avoid spamming logs with dump_page(), ratio limit hot-remove error test

Pull tracing fix from Steven Rostedt:
 "Fix the histogram logic from possibly crashing the kernel

  Working on the histogram code, I found that if you dereference a char
  pointer in a trace event that happens to point to user space, it can
  crash the kernel, as it does no checks of that pointer. I have code
  coming that will do this better, so just remove this ability to treat
  character pointers in trace events as stings in the histogram"

* tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Do not reference char * as a string in histograms

Pull devicetree fixes from Rob Herring:

 - Drop 'resets' as required on renesas,du

 - Moving of fixed string patterns for 'properties' instead of
   'patternProperties'

 - Drop more redundant minItems/maxItems that we merged in the merge
   window

 - Indentation warning fix for sja1105

* tag 'devicetree-fixes-for-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  dt-bindings: display: renesas,du: Make resets optional on R-Car H1
  dt-bindings: Move fixed string 'patternProperties' to 'properties'
  dt-bindings: More dropping redundant minItems/maxItems
  dt-bindings: net: dsa: sja1105: Fix indentation warnings

Pull arm64 fixes from Will Deacon:
 "The bulk of the diffstat consists of changes to our uaccess routines
  so that they fall back to bytewise copying prior to reporting complete
  failure when the initial (multi-byte) access faults.

  However, the most disappointing change here is that we've had to bump
  ARCH_DMA_MINALIGN back to 128 bytes thanks to Qualcomm's "Kryo" CPU,
  which ended up in the MSM8996 mobile SoC. Still, at least we're now
  aware of this design and one of the hardware designers confirmed the
  L2 cacheline size for us.

  Summary:

   - Fix instrumentation annotations for entry code

   - Ensure kernel MTE state is restored correctly on resume from suspend

   - Fix MTE fault from new strlen() routine

   - Fallback to byte-wise accesses on initial uaccess fault

   - Bump Clang requirement for BTI

   - Revert ARCH_DMA_MINALIGN back to 128 bytes (shakes fist at Qualcomm)"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: entry: fix KCOV suppression
  arm64: entry: add missing noinstr
  arm64: mte: fix restoration of GCR_EL1 from suspend
  arm64: Avoid premature usercopy failure
  arm64: Restrict ARM64_BTI_KERNEL to clang 12.0.0 and newer
  Revert "arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)"
  arm64: Add missing header <asm/smp.h> in two files
  arm64: fix strlen() with CONFIG_KASAN_HW_TAGS