linux-stable.git/kernel, branch v5.14.7

tracing/boot: Fix a hist trigger dependency for boot time tracing

2021-09-22T10:39:29+00:00

[ Upstream commit 6fe7c745f2acb73e4cc961d7f91125eef5a8861f ]

Fixes a build error when CONFIG_HIST_TRIGGERS=n with boot-time
tracing. Since the trigger_process_regex() is defined only
when CONFIG_HIST_TRIGGERS=y, if it is disabled, the 'actions'
event option also must be disabled.

Link: https://lkml.kernel.org/r/162856123376.203126.582144262622247352.stgit@devnote2

Fixes: 81a59555ff15 ("tracing/boot: Add per-event settings")
Signed-off-by: Masami Hiramatsu 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Sasha Levin

tracing/probes: Reject events which have the same name of existing one

2021-09-22T10:39:26+00:00

[ Upstream commit 8e242060c6a4947e8ae7d29794af6a581db08841 ]

Since kprobe_events and uprobe_events only check whether the
other same-type probe event has the same name or not, if the
user gives the same name of the existing tracepoint event (or
the other type of probe events), it silently fails to create
the tracefs entry (but registered.) as below.

/sys/kernel/tracing # ls events/task/task_rename
enable   filter   format   hist     id       trigger
/sys/kernel/tracing # echo p:task/task_rename vfs_read >> kprobe_events
[  113.048508] Could not create tracefs 'task_rename' directory
/sys/kernel/tracing # cat kprobe_events
p:task/task_rename vfs_read

To fix this issue, check whether the existing events have the
same name or not in trace_probe_register_event_call(). If exists,
it rejects to register the new event.

Link: https://lkml.kernel.org/r/162936876189.187130.17558311387542061930.stgit@devnote2

Signed-off-by: Masami Hiramatsu 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Sasha Levin

events: Reuse value read using READ_ONCE instead of re-reading it

2021-09-22T10:39:20+00:00

commit b89a05b21f46150ac10a962aa50109250b56b03b upstream.

In perf_event_addr_filters_apply, the task associated with
the event (event->ctx->task) is read using READ_ONCE at the beginning
of the function, checked, and then re-read from event->ctx->task,
voiding all guarantees of the checks. Reuse the value that was read by
READ_ONCE to ensure the consistency of the task struct throughout the
function.

Fixes: 375637bc52495 ("perf/core: Introduce address range filtering")
Signed-off-by: Baptiste Lepers 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/20210906015310.12802-1-baptiste.lepers@gmail.com
Signed-off-by: Greg Kroah-Hartman

tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads()

2021-09-18T11:44:05+00:00

commit 4b6b08f2e45edda4c067ac40833e3c1f84383c0b upstream.

When start_kthread() return error, the cpus_read_unlock() need
to be called.

Link: https://lkml.kernel.org/r/20210831022919.27630-1-qiang.zhang@windriver.com

Cc: 
Fixes: c8895e271f79 ("trace/osnoise: Support hotplug operations")
Acked-by: Daniel Bristot de Oliveira 
Signed-off-by: Qiang.Zhang 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman

memcg: enable accounting for pids in nested pid namespaces

2021-09-18T11:44:02+00:00

commit fab827dbee8c2e06ca4ba000fa6c48bcf9054aba upstream.

Commit 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg")
enabled memcg accounting for pids allocated from init_pid_ns.pid_cachep,
but forgot to adjust the setting for nested pid namespaces.  As a result,
pid memory is not accounted exactly where it is really needed, inside
memcg-limited containers with their own pid namespaces.

Pid was one the first kernel objects enabled for memcg accounting.
init_pid_ns.pid_cachep marked by SLAB_ACCOUNT and we can expect that any
new pids in the system are memcg-accounted.

Though recently I've noticed that it is wrong.  nested pid namespaces
creates own slab caches for pid objects, nested pids have increased size
because contain id both for all parent and for own pid namespaces.  The
problem is that these slab caches are _NOT_ marked by SLAB_ACCOUNT, as a
result any pids allocated in nested pid namespaces are not
memcg-accounted.

Pid struct in nested pid namespace consumes up to 500 bytes memory, 100000
such objects gives us up to ~50Mb unaccounted memory, this allow container
to exceed assigned memcg limits.

Link: https://lkml.kernel.org/r/8b6de616-fd1a-02c6-cbdb-976ecdcfa604@virtuozzo.com
Fixes: 5d097056c9a0 ("kmemcg: account certain kmem allocations to memcg")
Cc: stable@vger.kernel.org
Signed-off-by: Vasily Averin 
Reviewed-by: Michal Koutný 
Reviewed-by: Shakeel Butt 
Acked-by: Christian Brauner 
Acked-by: Roman Gushchin 
Cc: Michal Hocko 
Cc: Johannes Weiner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm/hugetlb: initialize hugetlb_usage in mm_init

2021-09-18T11:44:02+00:00

commit 13db8c50477d83ad3e3b9b0ae247e5cd833a7ae4 upstream.

After fork, the child process will get incorrect (2x) hugetlb_usage.  If
a process uses 5 2MB hugetlb pages in an anonymous mapping,

	HugetlbPages:	   10240 kB

and then forks, the child will show,

	HugetlbPages:	   20480 kB

The reason for double the amount is because hugetlb_usage will be copied
from the parent and then increased when we copy page tables from parent
to child.  Child will have 2x actual usage.

Fix this by adding hugetlb_count_init in mm_init.

Link: https://lkml.kernel.org/r/20210826071742.877-1-liuzixian4@huawei.com
Fixes: 5d317b2b6536 ("mm: hugetlb: proc: add HugetlbPages field to /proc/PID/status")
Signed-off-by: Liu Zixian 
Reviewed-by: Naoya Horiguchi 
Reviewed-by: Mike Kravetz 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

printk/console: Check consistent sequence number when handling race in console_unlock()

2021-09-18T11:44:00+00:00

commit 11e4b63abbe23872b45f325a7c6c8b7f9ff42cad upstream.

The standard printk() tries to flush the message to the console
immediately. It tries to take the console lock. If the lock is
already taken then the current owner is responsible for flushing
even the new message.

There is a small race window between checking whether a new message is
available and releasing the console lock. It is solved by re-checking
the state after releasing the console lock. If the check is positive
then console_unlock() tries to take the lock again and process the new
message as well.

The commit 996e966640ddea7b535c ("printk: remove logbuf_lock") causes that
console_seq is not longer read atomically. As a result, the re-check might
be done with an inconsistent 64-bit index.

Solve it by using the last sequence number that has been checked under
the console lock. In the worst case, it will take the lock again only
to realized that the new message has already been proceed. But it
was possible even before.

The variable next_seq is marked as __maybe_unused to call down compiler
warning when CONFIG_PRINTK is not defined.

Fixes: commit 996e966640ddea7b535c ("printk: remove logbuf_lock")
Reported-by: kernel test robot   # unused next_seq warning
Cc: stable@vger.kernel.org # 5.13
Signed-off-by: Petr Mladek 
Acked-by: Sergey Senozhatsky 
Reviewed-by: John Ogness 
Link: https://lore.kernel.org/r/20210702150657.26760-1-pmladek@suse.com
Signed-off-by: Greg Kroah-Hartman

locking/rtmutex: Set proper wait context for lockdep

2021-09-18T11:43:52+00:00

[ Upstream commit b41cda03765580caf7723b8c1b672d191c71013f ]

RT mutexes belong to the LD_WAIT_SLEEP class. Make them so.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Ingo Molnar 
Link: https://lore.kernel.org/r/20210815211302.031014562@linutronix.de
Signed-off-by: Sasha Levin

workqueue: Fix possible memory leaks in wq_numa_init()

2021-09-18T11:43:44+00:00

[ Upstream commit f728c4a9e8405caae69d4bc1232c54ff57b5d20f ]

In error handling branch "if (WARN_ON(node == NUMA_NO_NODE))", the
previously allocated memories are not released. Doing this before
allocating memory eliminates memory leaks.

tj: Note that the condition only occurs when the arch code is pretty broken
and the WARN_ON might as well be BUG_ON().

Signed-off-by: Zhen Lei 
Reviewed-by: Lai Jiangshan 
Signed-off-by: Tejun Heo 
Signed-off-by: Sasha Levin

rcu: Fix macro name CONFIG_TASKS_RCU_TRACE

2021-09-18T11:43:38+00:00

[ Upstream commit fed31a4dd3adb5455df7c704de2abb639a1dc1c0 ]

This commit fixes several typos where CONFIG_TASKS_RCU_TRACE should
instead be CONFIG_TASKS_TRACE_RCU.  Among other things, these typos
could cause CONFIG_TASKS_TRACE_RCU_READ_MB=y kernels to suffer from
memory-ordering bugs that could result in false-positive quiescent
states and too-short grace periods.

Signed-off-by: Zhouyi Zhou 
Signed-off-by: Paul E. McKenney 
Signed-off-by: Sasha Levin