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Author SHA1 Message Date
Jiapeng Chong
b576d375b5 fgraph: Use str_plural() in test_graph_storage_single()
Use existing str_plural() function rather than duplicating its
implementation.

./kernel/trace/trace_selftest.c:880:56-60: opportunity for str_plural(size).

Link: https://lore.kernel.org/linux-trace-kernel/20240618072014.20855-1-jiapeng.chong@linux.alibaba.com

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9349
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-07-01 19:57:51 -04:00
Luis Claudio R. Goncalves
c40583e19e rtla/osnoise: set the default threshold to 1us
Change the default threshold for osnoise to 1us, so that any noise
equal or above this value is recorded. Let the user set a higher
threshold if necessary.

Link: https://lore.kernel.org/linux-trace-kernel/Zmb-QhiiiI6jM9To@uudg.org

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Suggested-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Reviewed-by: Clark Williams <williams@redhat.com>
Signed-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-07-01 18:54:31 -04:00
Pu Lehui
d1a426171d bpf: Use precise image size for struct_ops trampoline
For trampoline using bpf_prog_pack, we need to generate a rw_image
buffer with size of (image_end - image). For regular trampoline, we use
the precise image size generated by arch_bpf_trampoline_size to allocate
rw_image. But for struct_ops trampoline, we allocate rw_image directly
using close to PAGE_SIZE size. We do not need to allocate for that much,
as the patch size is usually much smaller than PAGE_SIZE. Let's use
precise image size for it too.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com> #riscv
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20240622030437.3973492-2-pulehui@huaweicloud.com
2024-07-01 17:10:46 +02:00
John Stultz
ddae0ca2a8 sched: Move psi_account_irqtime() out of update_rq_clock_task() hotpath
It was reported that in moving to 6.1, a larger then 10%
regression was seen in the performance of
clock_gettime(CLOCK_THREAD_CPUTIME_ID,...).

Using a simple reproducer, I found:
5.10:
100000000 calls in 24345994193 ns => 243.460 ns per call
100000000 calls in 24288172050 ns => 242.882 ns per call
100000000 calls in 24289135225 ns => 242.891 ns per call

6.1:
100000000 calls in 28248646742 ns => 282.486 ns per call
100000000 calls in 28227055067 ns => 282.271 ns per call
100000000 calls in 28177471287 ns => 281.775 ns per call

The cause of this was finally narrowed down to the addition of
psi_account_irqtime() in update_rq_clock_task(), in commit
52b1364ba0 ("sched/psi: Add PSI_IRQ to track IRQ/SOFTIRQ
pressure").

In my initial attempt to resolve this, I leaned towards moving
all accounting work out of the clock_gettime() call path, but it
wasn't very pretty, so it will have to wait for a later deeper
rework. Instead, Peter shared this approach:

Rework psi_account_irqtime() to use its own psi_irq_time base
for accounting, and move it out of the hotpath, calling it
instead from sched_tick() and __schedule().

In testing this, we found the importance of ensuring
psi_account_irqtime() is run under the rq_lock, which Johannes
Weiner helpfully explained, so also add some lockdep annotations
to make that requirement clear.

With this change the performance is back in-line with 5.10:
6.1+fix:
100000000 calls in 24297324597 ns => 242.973 ns per call
100000000 calls in 24318869234 ns => 243.189 ns per call
100000000 calls in 24291564588 ns => 242.916 ns per call

Reported-by: Jimmy Shiu <jimmyshiu@google.com>
Originally-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Reviewed-by: Qais Yousef <qyousef@layalina.io>
Link: https://lore.kernel.org/r/20240618215909.4099720-1-jstultz@google.com
2024-07-01 13:01:44 +02:00
Wander Lairson Costa
b58652db66 sched/deadline: Fix task_struct reference leak
During the execution of the following stress test with linux-rt:

stress-ng --cyclic 30 --timeout 30 --minimize --quiet

kmemleak frequently reported a memory leak concerning the task_struct:

unreferenced object 0xffff8881305b8000 (size 16136):
  comm "stress-ng", pid 614, jiffies 4294883961 (age 286.412s)
  object hex dump (first 32 bytes):
    02 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00  .@..............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  debug hex dump (first 16 bytes):
    53 09 00 00 00 00 00 00 00 00 00 00 00 00 00 00  S...............
  backtrace:
    [<00000000046b6790>] dup_task_struct+0x30/0x540
    [<00000000c5ca0f0b>] copy_process+0x3d9/0x50e0
    [<00000000ced59777>] kernel_clone+0xb0/0x770
    [<00000000a50befdc>] __do_sys_clone+0xb6/0xf0
    [<000000001dbf2008>] do_syscall_64+0x5d/0xf0
    [<00000000552900ff>] entry_SYSCALL_64_after_hwframe+0x6e/0x76

The issue occurs in start_dl_timer(), which increments the task_struct
reference count and sets a timer. The timer callback, dl_task_timer,
is supposed to decrement the reference count upon expiration. However,
if enqueue_task_dl() is called before the timer expires and cancels it,
the reference count is not decremented, leading to the leak.

This patch fixes the reference leak by ensuring the task_struct
reference count is properly decremented when the timer is canceled.

Fixes: feff2e65ef ("sched/deadline: Unthrottle PI boosted threads while enqueuing")
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/20240620125618.11419-1-wander@redhat.com
2024-07-01 13:01:44 +02:00
Josh Don
2feab2492d Revert "sched/fair: Make sure to try to detach at least one movable task"
This reverts commit b0defa7ae0.

b0defa7ae0 changed the load balancing logic to ignore env.max_loop if
all tasks examined to that point were pinned. The goal of the patch was
to make it more likely to be able to detach a task buried in a long list
of pinned tasks. However, this has the unfortunate side effect of
creating an O(n) iteration in detach_tasks(), as we now must fully
iterate every task on a cpu if all or most are pinned. Since this load
balance code is done with rq lock held, and often in softirq context, it
is very easy to trigger hard lockups. We observed such hard lockups with
a user who affined O(10k) threads to a single cpu.

When I discussed this with Vincent he initially suggested that we keep
the limit on the number of tasks to detach, but increase the number of
tasks we can search. However, after some back and forth on the mailing
list, he recommended we instead revert the original patch, as it seems
likely no one was actually getting hit by the original issue.

Fixes: b0defa7ae0 ("sched/fair: Make sure to try to detach at least one movable task")
Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20240620214450.316280-1-joshdon@google.com
2024-07-01 13:01:43 +02:00
Linus Torvalds
3e334486ec TTY/Serial/Console fixes for 6.10-rc6
Here are a bunch of fixes/reverts for 6.10-rc6.  Include in here are:
   - revert the bunch of tty/serial/console changes that landed in -rc1
     that didn't quite work properly yet.  Everyone agreed to just revert
     them for now and will work on making them better for a future
     release instead of trying to quick fix the existing changes this
     late in the release cycle
   - 8250 driver port count bugfix
   - Other tiny serial port bugfixes for reported issues
 
 All of these have been in linux-next this week with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial / console fixes from Greg KH:
 "Here are a bunch of fixes/reverts for 6.10-rc6.  Include in here are:

   - revert the bunch of tty/serial/console changes that landed in -rc1
     that didn't quite work properly yet.

     Everyone agreed to just revert them for now and will work on making
     them better for a future release instead of trying to quick fix the
     existing changes this late in the release cycle

   - 8250 driver port count bugfix

   - Other tiny serial port bugfixes for reported issues

  All of these have been in linux-next this week with no reported
  issues"

* tag 'tty-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "printk: Save console options for add_preferred_console_match()"
  Revert "printk: Don't try to parse DEVNAME:0.0 console options"
  Revert "printk: Flag register_console() if console is set on command line"
  Revert "serial: core: Add support for DEVNAME:0.0 style naming for kernel console"
  Revert "serial: core: Handle serial console options"
  Revert "serial: 8250: Add preferred console in serial8250_isa_init_ports()"
  Revert "Documentation: kernel-parameters: Add DEVNAME:0.0 format for serial ports"
  Revert "serial: 8250: Fix add preferred console for serial8250_isa_init_ports()"
  Revert "serial: core: Fix ifdef for serial base console functions"
  serial: bcm63xx-uart: fix tx after conversion to uart_port_tx_limited()
  serial: core: introduce uart_port_tx_limited_flags()
  Revert "serial: core: only stop transmit when HW fifo is empty"
  serial: imx: set receiver level before starting uart
  tty: mcf: MCF54418 has 10 UARTS
  serial: 8250_omap: Implementation of Errata i2310
  tty: serial: 8250: Fix port count mismatch with the device
2024-06-30 08:57:43 -07:00
Linus Torvalds
3ffea9a7a6 - Fix "nosmp" and "maxcpus=0" after the parallel CPU bringup work went in and broke them
- Make sure CPU hotplug dynamic prepare states are actually executed
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Merge tag 'smp_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull smp fixes from Borislav Petkov:

 - Fix "nosmp" and "maxcpus=0" after the parallel CPU bringup work went
   in and broke them

 - Make sure CPU hotplug dynamic prepare states are actually executed

* tag 'smp_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu: Fix broken cmdline "nosmp" and "maxcpus=0"
  cpu/hotplug: Fix dynstate assignment in __cpuhp_setup_state_cpuslocked()
2024-06-30 08:41:42 -07:00
Linus Torvalds
03c8b0bd46 - Warn when an hrtimer doesn't get a callback supplied
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Merge tag 'timers_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Borislav Petkov:

 - Warn when an hrtimer doesn't get a callback supplied

* tag 'timers_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Prevent queuing of hrtimer without a function callback
2024-06-30 08:31:08 -07:00
Jeff Johnson
6073496a20 resource: add missing MODULE_DESCRIPTION()
Fix the 'make W=1' warning:
WARNING: modpost: missing MODULE_DESCRIPTION() in kernel/resource_kunit.o

Link: https://lkml.kernel.org/r/20240529-md-kernel-resource_kunit-v1-1-bb719784b714@quicinc.com
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-28 19:36:30 -07:00
James Morse
4e1a7df454 cpumask: Add enabled cpumask for present CPUs that can be brought online
The 'offline' file in sysfs shows all offline CPUs, including those
that aren't present. User-space is expected to remove not-present CPUs
from this list to learn which CPUs could be brought online.

CPUs can be present but not-enabled. These CPUs can't be brought online
until the firmware policy changes, which comes with an ACPI notification
that will register the CPUs.

With only the offline and present files, user-space is unable to
determine which CPUs it can try to bring online. Add a new CPU mask
that shows this based on all the registered CPUs.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>
Tested-by: Jianyong Wu <jianyong.wu@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240529133446.28446-20-Jonathan.Cameron@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-06-28 18:38:33 +01:00
Chen Ridong
1be59c97c8 cgroup/cpuset: Prevent UAF in proc_cpuset_show()
An UAF can happen when /proc/cpuset is read as reported in [1].

This can be reproduced by the following methods:
1.add an mdelay(1000) before acquiring the cgroup_lock In the
 cgroup_path_ns function.
2.$cat /proc/<pid>/cpuset   repeatly.
3.$mount -t cgroup -o cpuset cpuset /sys/fs/cgroup/cpuset/
$umount /sys/fs/cgroup/cpuset/   repeatly.

The race that cause this bug can be shown as below:

(umount)		|	(cat /proc/<pid>/cpuset)
css_release		|	proc_cpuset_show
css_release_work_fn	|	css = task_get_css(tsk, cpuset_cgrp_id);
css_free_rwork_fn	|	cgroup_path_ns(css->cgroup, ...);
cgroup_destroy_root	|	mutex_lock(&cgroup_mutex);
rebind_subsystems	|
cgroup_free_root 	|
			|	// cgrp was freed, UAF
			|	cgroup_path_ns_locked(cgrp,..);

When the cpuset is initialized, the root node top_cpuset.css.cgrp
will point to &cgrp_dfl_root.cgrp. In cgroup v1, the mount operation will
allocate cgroup_root, and top_cpuset.css.cgrp will point to the allocated
&cgroup_root.cgrp. When the umount operation is executed,
top_cpuset.css.cgrp will be rebound to &cgrp_dfl_root.cgrp.

The problem is that when rebinding to cgrp_dfl_root, there are cases
where the cgroup_root allocated by setting up the root for cgroup v1
is cached. This could lead to a Use-After-Free (UAF) if it is
subsequently freed. The descendant cgroups of cgroup v1 can only be
freed after the css is released. However, the css of the root will never
be released, yet the cgroup_root should be freed when it is unmounted.
This means that obtaining a reference to the css of the root does
not guarantee that css.cgrp->root will not be freed.

Fix this problem by using rcu_read_lock in proc_cpuset_show().
As cgroup_root is kfree_rcu after commit d23b5c5777
("cgroup: Make operations on the cgroup root_list RCU safe"),
css->cgroup won't be freed during the critical section.
To call cgroup_path_ns_locked, css_set_lock is needed, so it is safe to
replace task_get_css with task_css.

[1] https://syzkaller.appspot.com/bug?extid=9b1ff7be974a403aa4cd

Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2024-06-28 07:10:31 -10:00
Andrei Vagin
bfafe5efa9 seccomp: release task filters when the task exits
Previously, seccomp filters were released in release_task(), which
required the process to exit and its zombie to be collected. However,
exited threads/processes can't trigger any seccomp events, making it
more logical to release filters upon task exits.

This adjustment simplifies scenarios where a parent is tracing its child
process. The parent process can now handle all events from a seccomp
listening descriptor and then call wait to collect a child zombie.

seccomp_filter_release takes the siglock to avoid races with
seccomp_sync_threads. There was an idea to bypass taking the lock by
checking PF_EXITING, but it can be set without holding siglock if
threads have SIGNAL_GROUP_EXIT. This means it can happen concurently
with seccomp_filter_release.

This change also fixes another minor problem. Suppose that a group
leader installs the new filter without SECCOMP_FILTER_FLAG_TSYNC, exits,
and becomes a zombie. Without this change, SECCOMP_FILTER_FLAG_TSYNC
from any other thread can never succeed, seccomp_can_sync_threads() will
check a zombie leader and is_ancestor() will fail.

Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrei Vagin <avagin@google.com>
Link: https://lore.kernel.org/r/20240628021014.231976-3-avagin@google.com
Reviewed-by: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Kees Cook <kees@kernel.org>
2024-06-28 09:37:11 -07:00
Andrei Vagin
95036a79e7 seccomp: interrupt SECCOMP_IOCTL_NOTIF_RECV when all users have exited
SECCOMP_IOCTL_NOTIF_RECV promptly returns when a seccomp filter becomes
unused, as a filter without users can't trigger any events.

Previously, event listeners had to rely on epoll to detect when all
processes had exited.

The change is based on the 'commit 99cdb8b9a5 ("seccomp: notify about
unused filter")' which implemented (E)POLLHUP notifications.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrei Vagin <avagin@google.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20240628021014.231976-2-avagin@google.com
Reviewed-by: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Kees Cook <kees@kernel.org>
2024-06-28 09:37:11 -07:00
Frederic Weisbecker
677ab23bdf rcu/exp: Remove redundant full memory barrier at the end of GP
A full memory barrier is necessary at the end of the expedited grace
period to order:

1) The grace period completion (pictured by the GP sequence
   number) with all preceding accesses. This pairs with rcu_seq_end()
   performed by the concurrent kworker.

2) The grace period completion and subsequent post-GP update side
   accesses. Pairs again against rcu_seq_end().

This full barrier is already provided by the final sync_exp_work_done()
test, making the subsequent explicit one redundant. Remove it and
improve comments.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
2024-06-28 06:44:12 -07:00
Frederic Weisbecker
55911a9f42 rcu: Remove full memory barrier on RCU stall printout
RCU stall printout fetches the EQS state of a CPU with a preceding full
memory barrier. However there is nothing to order this read against at
this debugging stage. It is inherently racy when performed remotely.

Do a plain read instead.

This was the last user of rcu_dynticks_snap().

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
2024-06-28 06:44:12 -07:00
Frederic Weisbecker
e7a3c8ea6e rcu: Remove full memory barrier on boot time eqs sanity check
When the boot CPU initializes the per-CPU data on behalf of all possible
CPUs, a sanity check is performed on each of them to make sure none is
initialized in an extended quiescent state.

This check involves a full memory barrier which is useless at this early
boot stage.

Do a plain access instead.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
2024-06-28 06:44:12 -07:00
Frederic Weisbecker
33c0860bf7 rcu/exp: Remove superfluous full memory barrier upon first EQS snapshot
When the grace period kthread checks the extended quiescent state
counter of a CPU, full ordering is necessary to ensure that either:

* If the GP kthread observes the remote target in an extended quiescent
  state, then that target must observe all accesses prior to the current
  grace period, including the current grace period sequence number, once
  it exits that extended quiescent state.

or:

* If the GP kthread observes the remote target NOT in an extended
  quiescent state, then the target further entering in an extended
  quiescent state must observe all accesses prior to the current
  grace period, including the current grace period sequence number, once
  it enters that extended quiescent state.

This ordering is enforced through a full memory barrier placed right
before taking the first EQS snapshot. However this is superfluous
because the snapshot is taken while holding the target's rnp lock which
provides the necessary ordering through its chain of
smp_mb__after_unlock_lock().

Remove the needless explicit barrier before the snapshot and put a
comment about the implicit barrier newly relied upon here.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2024-06-28 06:43:34 -07:00
Frederic Weisbecker
9a7e73c9be rcu: Remove superfluous full memory barrier upon first EQS snapshot
When the grace period kthread checks the extended quiescent state
counter of a CPU, full ordering is necessary to ensure that either:

* If the GP kthread observes the remote target in an extended quiescent
  state, then that target must observe all accesses prior to the current
  grace period, including the current grace period sequence number, once
  it exits that extended quiescent state.

or:

* If the GP kthread observes the remote target NOT in an extended
  quiescent state, then the target further entering in an extended
  quiescent state must observe all accesses prior to the current
  grace period, including the current grace period sequence number, once
  it enters that extended quiescent state.

This ordering is enforced through a full memory barrier placed right
before taking the first EQS snapshot. However this is superfluous
because the snapshot is taken while holding the target's rnp lock which
provides the necessary ordering through its chain of
smp_mb__after_unlock_lock().

Remove the needless explicit barrier before the snapshot and put a
comment about the implicit barrier newly relied upon here.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2024-06-28 06:43:34 -07:00
Frederic Weisbecker
0a5e9bd31e rcu: Remove full ordering on second EQS snapshot
When the grace period kthread checks the extended quiescent state
counter of a CPU, full ordering is necessary to ensure that either:

* If the GP kthread observes the remote target in an extended quiescent
  state, then that target must observe all accesses prior to the current
  grace period, including the current grace period sequence number, once
  it exits that extended quiescent state. Also the GP kthread must
  observe all accesses performed by the target prior it entering in
  EQS.

or:

* If the GP kthread observes the remote target NOT in an extended
  quiescent state, then the target further entering in an extended
  quiescent state must observe all accesses prior to the current
  grace period, including the current grace period sequence number, once
  it enters that extended quiescent state. Also the GP kthread later
  observing that EQS must also observe all accesses performed by the
  target prior it entering in EQS.

This ordering is explicitly performed both on the first EQS snapshot
and on the second one as well through the combination of a preceding
full barrier followed by an acquire read. However the second snapshot's
full memory barrier is redundant and not needed to enforce the above
guarantees:

    GP kthread                  Remote target
    ----                        -----
    // Access prior GP
    WRITE_ONCE(A, 1)
    // first snapshot
    smp_mb()
    x = smp_load_acquire(EQS)
                               // Access prior GP
                               WRITE_ONCE(B, 1)
                               // EQS enter
                               // implied full barrier by atomic_add_return()
                               atomic_add_return(RCU_DYNTICKS_IDX, EQS)
                               // implied full barrier by atomic_add_return()
                               READ_ONCE(A)
    // second snapshot
    y = smp_load_acquire(EQS)
    z = READ_ONCE(B)

If the GP kthread above fails to observe the remote target in EQS
(x not in EQS), the remote target will observe A == 1 after further
entering in EQS. Then the second snapshot taken by the GP kthread only
need to be an acquire read in order to observe z == 1.

Therefore remove the needless full memory barrier on second snapshot.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2024-06-28 06:43:33 -07:00
Jakub Kicinski
193b9b2002 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts.

Adjacent changes:
  e3f02f32a0 ("ionic: fix kernel panic due to multi-buffer handling")
  d9c0420999 ("ionic: Mark error paths in the data path as unlikely")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-27 12:14:11 -07:00
Linus Torvalds
adfbe3640b asm-generic fixes for 6.10
These are some bugfixes for system call ABI issues I found while
 working on a cleanup series. None of these are urgent since these
 bugs have gone unnoticed for many years, but I think we probably
 want to backport them all to stable kernels, so it makes sense
 to have the fixes included as early as possible.
 
 One more fix addresses a compile-time warning in kallsyms that was
 uncovered by a patch I did to enable additional warnings in 6.10. I had
 mistakenly thought that this fix was already merged through the module
 tree, but as Geert pointed out it was still missing.
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Merge tag 'asm-generic-fixes-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic fixes from Arnd Bergmann:
 "These are some bugfixes for system call ABI issues I found while
  working on a cleanup series. None of these are urgent since these bugs
  have gone unnoticed for many years, but I think we probably want to
  backport them all to stable kernels, so it makes sense to have the
  fixes included as early as possible.

  One more fix addresses a compile-time warning in kallsyms that was
  uncovered by a patch I did to enable additional warnings in 6.10. I
  had mistakenly thought that this fix was already merged through the
  module tree, but as Geert pointed out it was still missing"

* tag 'asm-generic-fixes-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  kallsyms: rework symbol lookup return codes
  linux/syscalls.h: add missing __user annotations
  syscalls: mmap(): use unsigned offset type consistently
  s390: remove native mmap2() syscall
  hexagon: fix fadvise64_64 calling conventions
  csky, hexagon: fix broken sys_sync_file_range
  sh: rework sync_file_range ABI
  powerpc: restore some missing spu syscalls
  parisc: use generic sys_fanotify_mark implementation
  parisc: use correct compat recv/recvfrom syscalls
  sparc: fix compat recv/recvfrom syscalls
  sparc: fix old compat_sys_select()
  syscalls: fix compat_sys_io_pgetevents_time64 usage
  ftruncate: pass a signed offset
2024-06-27 10:53:52 -07:00
Linus Torvalds
fd19d4a492 Including fixes from can, bpf and netfilter.
Current release - regressions:
 
   - core: add softirq safety to netdev_rename_lock
 
   - tcp: fix tcp_rcv_fastopen_synack() to enter TCP_CA_Loss for failed TFO
 
   - batman-adv: fix RCU race at module unload time
 
 Current release - new code bugs:
 
 Previous releases - regressions:
 
   - openvswitch: get related ct labels from its master if it is not confirmed
 
   - eth: bonding: fix incorrect software timestamping report
 
   - eth: mlxsw: fix memory corruptions on spectrum-4 systems
 
   - eth: ionic: use dev_consume_skb_any outside of napi
 
 Previous releases - always broken:
 
   - netfilter: fully validate NFT_DATA_VALUE on store to data registers
 
   - unix: several fixes for OoB data
 
   - tcp: fix race for duplicate reqsk on identical SYN
 
   - bpf:
     - fix may_goto with negative offset.
     - fix the corner case with may_goto and jump to the 1st insn.
     - fix overrunning reservations in ringbuf
 
   - can:
     - j1939: recover socket queue on CAN bus error during BAM transmission
     - mcp251xfd: fix infinite loop when xmit fails
 
   - dsa: microchip: monitor potential faults in half-duplex mode
 
   - eth: vxlan: pull inner IP header in vxlan_xmit_one()
 
   - eth: ionic: fix kernel panic due to multi-buffer handling
 
 Misc:
 
   - selftest: unix tests refactor and a lot of new cases added
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from can, bpf and netfilter.

  There are a bunch of regressions addressed here, but hopefully nothing
  spectacular. We are still waiting the driver fix from Intel, mentioned
  by Jakub in the previous networking pull.

  Current release - regressions:

   - core: add softirq safety to netdev_rename_lock

   - tcp: fix tcp_rcv_fastopen_synack() to enter TCP_CA_Loss for failed
     TFO

   - batman-adv: fix RCU race at module unload time

  Previous releases - regressions:

   - openvswitch: get related ct labels from its master if it is not
     confirmed

   - eth: bonding: fix incorrect software timestamping report

   - eth: mlxsw: fix memory corruptions on spectrum-4 systems

   - eth: ionic: use dev_consume_skb_any outside of napi

  Previous releases - always broken:

   - netfilter: fully validate NFT_DATA_VALUE on store to data registers

   - unix: several fixes for OoB data

   - tcp: fix race for duplicate reqsk on identical SYN

   - bpf:
       - fix may_goto with negative offset
       - fix the corner case with may_goto and jump to the 1st insn
       - fix overrunning reservations in ringbuf

   - can:
       - j1939: recover socket queue on CAN bus error during BAM
         transmission
       - mcp251xfd: fix infinite loop when xmit fails

   - dsa: microchip: monitor potential faults in half-duplex mode

   - eth: vxlan: pull inner IP header in vxlan_xmit_one()

   - eth: ionic: fix kernel panic due to multi-buffer handling

  Misc:

   - selftest: unix tests refactor and a lot of new cases added"

* tag 'net-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (61 commits)
  net: mana: Fix possible double free in error handling path
  selftest: af_unix: Check SIOCATMARK after every send()/recv() in msg_oob.c.
  af_unix: Fix wrong ioctl(SIOCATMARK) when consumed OOB skb is at the head.
  selftest: af_unix: Check EPOLLPRI after every send()/recv() in msg_oob.c
  selftest: af_unix: Check SIGURG after every send() in msg_oob.c
  selftest: af_unix: Add SO_OOBINLINE test cases in msg_oob.c
  af_unix: Don't stop recv() at consumed ex-OOB skb.
  selftest: af_unix: Add non-TCP-compliant test cases in msg_oob.c.
  af_unix: Don't stop recv(MSG_DONTWAIT) if consumed OOB skb is at the head.
  af_unix: Stop recv(MSG_PEEK) at consumed OOB skb.
  selftest: af_unix: Add msg_oob.c.
  selftest: af_unix: Remove test_unix_oob.c.
  tracing/net_sched: NULL pointer dereference in perf_trace_qdisc_reset()
  netfilter: nf_tables: fully validate NFT_DATA_VALUE on store to data registers
  net: usb: qmi_wwan: add Telit FN912 compositions
  tcp: fix tcp_rcv_fastopen_synack() to enter TCP_CA_Loss for failed TFO
  ionic: use dev_consume_skb_any outside of napi
  net: dsa: microchip: fix wrong register write when masking interrupt
  Fix race for duplicate reqsk on identical SYN
  ibmvnic: Add tx check to prevent skb leak
  ...
2024-06-27 10:05:35 -07:00
Arnd Bergmann
7e1f4eb9a6 kallsyms: rework symbol lookup return codes
Building with W=1 in some configurations produces a false positive
warning for kallsyms:

kernel/kallsyms.c: In function '__sprint_symbol.isra':
kernel/kallsyms.c:503:17: error: 'strcpy' source argument is the same as destination [-Werror=restrict]
  503 |                 strcpy(buffer, name);
      |                 ^~~~~~~~~~~~~~~~~~~~

This originally showed up while building with -O3, but later started
happening in other configurations as well, depending on inlining
decisions. The underlying issue is that the local 'name' variable is
always initialized to the be the same as 'buffer' in the called functions
that fill the buffer, which gcc notices while inlining, though it could
see that the address check always skips the copy.

The calling conventions here are rather unusual, as all of the internal
lookup functions (bpf_address_lookup, ftrace_mod_address_lookup,
ftrace_func_address_lookup, module_address_lookup and
kallsyms_lookup_buildid) already use the provided buffer and either return
the address of that buffer to indicate success, or NULL for failure,
but the callers are written to also expect an arbitrary other buffer
to be returned.

Rework the calling conventions to return the length of the filled buffer
instead of its address, which is simpler and easier to follow as well
as avoiding the warning. Leave only the kallsyms_lookup() calling conventions
unchanged, since that is called from 16 different functions and
adapting this would be a much bigger change.

Link: https://lore.kernel.org/lkml/20200107214042.855757-1-arnd@arndb.de/
Link: https://lore.kernel.org/lkml/20240326130647.7bfb1d92@gandalf.local.home/
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-06-27 17:43:40 +02:00
Linus Torvalds
24ca36a562 workqueue: Fixes for v6.10-rc5
Two patches to fix kworker name formatting.
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Merge tag 'wq-for-6.10-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue fixes from Tejun Heo:
 "Two patches to fix kworker name formatting"

* tag 'wq-for-6.10-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Increase worker desc's length to 32
  workqueue: Refactor worker ID formatting and make wq_worker_comm() use full ID string
2024-06-26 15:01:33 -07:00
Matt Bobrowski
ec2b9a5e11 bpf: add missing check_func_arg_reg_off() to prevent out-of-bounds memory accesses
Currently, it's possible to pass in a modified CONST_PTR_TO_DYNPTR to
a global function as an argument. The adverse effects of this is that
BPF helpers can continue to make use of this modified
CONST_PTR_TO_DYNPTR from within the context of the global function,
which can unintentionally result in out-of-bounds memory accesses and
therefore compromise overall system stability i.e.

[  244.157771] BUG: KASAN: slab-out-of-bounds in bpf_dynptr_data+0x137/0x140
[  244.161345] Read of size 8 at addr ffff88810914be68 by task test_progs/302
[  244.167151] CPU: 0 PID: 302 Comm: test_progs Tainted: G O E 6.10.0-rc3-00131-g66b586715063 #533
[  244.174318] Call Trace:
[  244.175787]  <TASK>
[  244.177356]  dump_stack_lvl+0x66/0xa0
[  244.179531]  print_report+0xce/0x670
[  244.182314]  ? __virt_addr_valid+0x200/0x3e0
[  244.184908]  kasan_report+0xd7/0x110
[  244.187408]  ? bpf_dynptr_data+0x137/0x140
[  244.189714]  ? bpf_dynptr_data+0x137/0x140
[  244.192020]  bpf_dynptr_data+0x137/0x140
[  244.194264]  bpf_prog_b02a02fdd2bdc5fa_global_call_bpf_dynptr_data+0x22/0x26
[  244.198044]  bpf_prog_b0fe7b9d7dc3abde_callback_adjust_bpf_dynptr_reg_off+0x1f/0x23
[  244.202136]  bpf_user_ringbuf_drain+0x2c7/0x570
[  244.204744]  ? 0xffffffffc0009e58
[  244.206593]  ? __pfx_bpf_user_ringbuf_drain+0x10/0x10
[  244.209795]  bpf_prog_33ab33f6a804ba2d_user_ringbuf_callback_const_ptr_to_dynptr_reg_off+0x47/0x4b
[  244.215922]  bpf_trampoline_6442502480+0x43/0xe3
[  244.218691]  __x64_sys_prlimit64+0x9/0xf0
[  244.220912]  do_syscall_64+0xc1/0x1d0
[  244.223043]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  244.226458] RIP: 0033:0x7ffa3eb8f059
[  244.228582] Code: 08 89 e8 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 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 73 01 c3 48 8b 0d 8f 1d 0d 00 f7 d8 64 89 01 48
[  244.241307] RSP: 002b:00007ffa3e9c6eb8 EFLAGS: 00000206 ORIG_RAX: 000000000000012e
[  244.246474] RAX: ffffffffffffffda RBX: 00007ffa3e9c7cdc RCX: 00007ffa3eb8f059
[  244.250478] RDX: 00007ffa3eb162b4 RSI: 0000000000000000 RDI: 00007ffa3e9c7fb0
[  244.255396] RBP: 00007ffa3e9c6ed0 R08: 00007ffa3e9c76c0 R09: 0000000000000000
[  244.260195] R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffff80
[  244.264201] R13: 000000000000001c R14: 00007ffc5d6b4260 R15: 00007ffa3e1c7000
[  244.268303]  </TASK>

Add a check_func_arg_reg_off() to the path in which the BPF verifier
verifies the arguments of global function arguments, specifically
those which take an argument of type ARG_PTR_TO_DYNPTR |
MEM_RDONLY. Also, process_dynptr_func() doesn't appear to perform any
explicit and strict type matching on the supplied register type, so
let's also enforce that a register either type PTR_TO_STACK or
CONST_PTR_TO_DYNPTR is by the caller.

Reported-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Matt Bobrowski <mattbobrowski@google.com>
Link: https://lore.kernel.org/r/20240625062857.92760-1-mattbobrowski@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-06-26 13:17:32 -07:00
Nicholas Piggin
98f887f820 workqueue: Improve scalability of workqueue watchdog touch
On a ~2000 CPU powerpc system, hard lockups have been observed in the
workqueue code when stop_machine runs (in this case due to CPU hotplug).
This is due to lots of CPUs spinning in multi_cpu_stop, calling
touch_nmi_watchdog() which ends up calling wq_watchdog_touch().
wq_watchdog_touch() writes to the global variable wq_watchdog_touched,
and that can find itself in the same cacheline as other important
workqueue data, which slows down operations to the point of lockups.

In the case of the following abridged trace, worker_pool_idr was in
the hot line, causing the lockups to always appear at idr_find.

  watchdog: CPU 1125 self-detected hard LOCKUP @ idr_find
  Call Trace:
  get_work_pool
  __queue_work
  call_timer_fn
  run_timer_softirq
  __do_softirq
  do_softirq_own_stack
  irq_exit
  timer_interrupt
  decrementer_common_virt
  * interrupt: 900 (timer) at multi_cpu_stop
  multi_cpu_stop
  cpu_stopper_thread
  smpboot_thread_fn
  kthread

Fix this by having wq_watchdog_touch() only write to the line if the
last time a touch was recorded exceeds 1/4 of the watchdog threshold.

Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2024-06-25 06:55:44 -10:00
Nicholas Piggin
18e24deb1c workqueue: wq_watchdog_touch is always called with valid CPU
Warn in the case it is called with cpu == -1. This does not appear
to happen anywhere.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2024-06-25 06:55:16 -10:00
Phil Chang
5a830bbce3 hrtimer: Prevent queuing of hrtimer without a function callback
The hrtimer function callback must not be NULL. It has to be specified by
the call side but it is not validated by the hrtimer code. When a hrtimer
is queued without a function callback, the kernel crashes with a null
pointer dereference when trying to execute the callback in __run_hrtimer().

Introduce a validation before queuing the hrtimer in
hrtimer_start_range_ns().

[anna-maria: Rephrase commit message]

Signed-off-by: Phil Chang <phil.chang@mediatek.com>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
2024-06-25 16:54:27 +02:00
Arnd Bergmann
d3882564a7 syscalls: fix compat_sys_io_pgetevents_time64 usage
Using sys_io_pgetevents() as the entry point for compat mode tasks
works almost correctly, but misses the sign extension for the min_nr
and nr arguments.

This was addressed on parisc by switching to
compat_sys_io_pgetevents_time64() in commit 6431e92fc8 ("parisc:
io_pgetevents_time64() needs compat syscall in 32-bit compat mode"),
as well as by using more sophisticated system call wrappers on x86 and
s390. However, arm64, mips, powerpc, sparc and riscv still have the
same bug.

Change all of them over to use compat_sys_io_pgetevents_time64()
like parisc already does. This was clearly the intention when the
function was originally added, but it got hooked up incorrectly in
the tables.

Cc: stable@vger.kernel.org
Fixes: 48166e6ea4 ("y2038: add 64-bit time_t syscalls to all 32-bit architectures")
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-06-25 15:57:20 +02:00
Greg Kroah-Hartman
cc8d5a2f09 Revert "printk: Save console options for add_preferred_console_match()"
This reverts commit f03e8c1060.

Let's roll back all of the serial core and printk console changes that
went into 6.10-rc1 as there still are problems with them that need to be
sorted out.

Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1
Reported-by: Petr Mladek <pmladek@suse.com>
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-25 07:58:10 +02:00
Greg Kroah-Hartman
64f9f010c6 Revert "printk: Don't try to parse DEVNAME:0.0 console options"
This reverts commit 8a831c584e.

Let's roll back all of the serial core and printk console changes that
went into 6.10-rc1 as there still are problems with them that need to be
sorted out.

Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1
Reported-by: Petr Mladek <pmladek@suse.com>
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-25 07:58:07 +02:00
Greg Kroah-Hartman
deb091cb05 Revert "printk: Flag register_console() if console is set on command line"
This reverts commit b73c9cbe4f.

Let's roll back all of the serial core and printk console changes that
went into 6.10-rc1 as there still are problems with them that need to be
sorted out.

Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1
Reported-by: Petr Mladek <pmladek@suse.com>
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-25 07:58:03 +02:00
Yongliang Gao
abd8ac0557 hung_task: ignore hung_task_warnings when hung_task_panic is enabled
If hung_task_panic is enabled, don't consider the value of
hung_task_warnings and display the information of the hung tasks.

In some cases, hung_task_panic might not be initially set up, after
several hung tasks occur, the hung_task_warnings count reaches zero.  If
hung_task_panic is set up later, it may not display any helpful hung task
info in dmesg, only showing messages like:

Kernel panic - not syncing: hung_task: blocked tasks
CPU: 3 PID: 58 Comm: khungtaskd Not tainted 6.10.0-rc3 #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
 <TASK>
 panic+0x2f3/0x320
 watchdog+0x2dd/0x510
 ? __pfx_watchdog+0x10/0x10
 kthread+0xe0/0x110
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x2f/0x40
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Link: https://lkml.kernel.org/r/20240613033159.3446265-1-leonylgao@gmail.com
Signed-off-by: Yongliang Gao <leonylgao@tencent.com>
Reviewed-by: Huang Cun <cunhuang@tencent.com>
Cc: Joel Granados <j.granados@samsung.com>
Cc: John Siddle <jsiddle@redhat.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:10 -07:00
Wenchao Hao
5eb1911a8c crash: remove header files which are included more than once
Following warning is reported, so remove these duplicated header
including:

./kernel/crash_reserve.c: linux/kexec.h is included more than once.

This is just a clean code, no logic changed.

Link: https://lkml.kernel.org/r/20240606091427.3512314-1-haowenchao22@gmail.com
Signed-off-by: Wenchao Hao <haowenchao22@gmail.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:08 -07:00
Jani Nikula
2f183c6834 kernel/panic: add verbose logging of kernel taints in backtraces
With nearly 20 taint flags and respective characters, it's getting a bit
difficult to remember what each taint flag character means.  Add verbose
logging of the set taints in the format:

Tainted: [P]=PROPRIETARY_MODULE, [W]=WARN

in dump_stack_print_info() when there are taints.

Note that the "negative flag" G is not included.

Link: https://lkml.kernel.org/r/7321e306166cb2ca2807ab8639e665baa2462e9c.1717146197.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:05 -07:00
Jani Nikula
f36fc96c15 kernel/panic: initialize taint_flags[] using a macro
Make it easier to extend struct taint_flags in follow-up.

Link: https://lkml.kernel.org/r/8a2498285d37953cfad9dce939ed3abef61051bd.1717146197.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:05 -07:00
Jani Nikula
aff1db0e4e kernel/panic: convert print_tainted() to use struct seq_buf internally
Convert print_tainted() to use struct seq_buf internally in order to be
more aware of the buffer constraints as well as make it easier to extend
in follow-up work.

Link: https://lkml.kernel.org/r/cb6006fa7c0f82a6b6885e8eea2920fcdc4fc9d0.1717146197.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:05 -07:00
Jani Nikula
f4b6242338 kernel/panic: return early from print_tainted() when not tainted
Reduce indent to make follow-up changes slightly easier on the eyes.

Link: https://lkml.kernel.org/r/01d6c03de1c9d1b52b59c652a3704a0a9886ed63.1717146197.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:04 -07:00
Kuan-Wei Chiu
bfe3127180 lib min_heap: rename min_heapify() to min_heap_sift_down()
After adding min_heap_sift_up(), the naming convention has been adjusted
to maintain consistency with the min_heap_sift_up().  Consequently,
min_heapify() has been renamed to min_heap_sift_down().

Link: https://lkml.kernel.org/CAP-5=fVcBAxt8Mw72=NCJPRJfjDaJcqk4rjbadgouAEAHz_q1A@mail.gmail.com
Link: https://lkml.kernel.org/r/20240524152958.919343-13-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Cc: Coly Li <colyli@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Sakai <msakai@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:24:59 -07:00
Kuan-Wei Chiu
267607e875 lib min_heap: add args for min_heap_callbacks
Add a third parameter 'args' for the 'less' and 'swp' functions in the
'struct min_heap_callbacks'.  This additional parameter allows these
comparison and swap functions to handle extra arguments when necessary.

Link: https://lkml.kernel.org/r/20240524152958.919343-9-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Cc: Coly Li <colyli@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Sakai <msakai@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:24:58 -07:00
Kuan-Wei Chiu
873ce25766 lib min_heap: add type safe interface
Implement a type-safe interface for min_heap using strong type pointers
instead of void * in the data field.  This change includes adding small
macro wrappers around functions, enabling the use of __minheap_cast and
__minheap_obj_size macros for type casting and obtaining element size. 
This implementation removes the necessity of passing element size in
min_heap_callbacks.  Additionally, introduce the MIN_HEAP_PREALLOCATED
macro for preallocating some elements.

Link: https://lkml.kernel.org/ioyfizrzq7w7mjrqcadtzsfgpuntowtjdw5pgn4qhvsdp4mqqg@nrlek5vmisbu
Link: https://lkml.kernel.org/r/20240524152958.919343-5-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Cc: Coly Li <colyli@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Sakai <msakai@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:24:57 -07:00
Kuan-Wei Chiu
ddd36b7ee1 perf/core: fix several typos
Patch series "treewide: Refactor heap related implementation", v6.

This patch series focuses on several adjustments related to heap
implementation.  Firstly, a type-safe interface has been added to the
min_heap, along with the introduction of several new functions to enhance
its functionality.  Additionally, the heap implementation for bcache and
bcachefs has been replaced with the generic min_heap implementation from
include/linux.  Furthermore, several typos have been corrected.

Previous discussion with Kent Overstreet:
https://lkml.kernel.org/ioyfizrzq7w7mjrqcadtzsfgpuntowtjdw5pgn4qhvsdp4mqqg@nrlek5vmisbu


This patch (of 16):

Replace 'artifically' with 'artificially'.
Replace 'irrespecive' with 'irrespective'.
Replace 'futher' with 'further'.
Replace 'sufficent' with 'sufficient'.

Link: https://lkml.kernel.org/r/20240524152958.919343-1-visitorckw@gmail.com
Link: https://lkml.kernel.org/r/20240524152958.919343-2-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Cc: Coly Li <colyli@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Sakai <msakai@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:24:56 -07:00
Uros Bizjak
47e39c7933 fork: use this_cpu_try_cmpxchg() in try_release_thread_stack_to_cache()
Use this_cpu_try_cmpxchg() instead of this_cpu_cmpxchg (*ptr, old, new) ==
old in try_release_thread_stack_to_cache.  x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg (and
related move instruction in front of cmpxchg).

No functional change intended.

[ubizjak@gmail.com: simplify the for loop a bit]
  Link: https://lkml.kernel.org/r/20240523214442.21102-1-ubizjak@gmail.com
Link: https://lkml.kernel.org/r/20240523073530.8128-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:24:56 -07:00
Jeff Johnson
82a9d6bdd4 backtracetest: add MODULE_DESCRIPTION()
Fix the 'make W=1' warning:

WARNING: modpost: missing MODULE_DESCRIPTION() in kernel/backtracetest.o

Link: https://lkml.kernel.org/r/20240518-md-backtracetest-v1-1-fab9f942c139@quicinc.com
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:24:55 -07:00
Jakub Kicinski
482000cf7f bpf-for-netdev
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Merge tag 'for-netdev' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2024-06-24

We've added 12 non-merge commits during the last 10 day(s) which contain
a total of 10 files changed, 412 insertions(+), 16 deletions(-).

The main changes are:

1) Fix a BPF verifier issue validating may_goto with a negative offset,
   from Alexei Starovoitov.

2) Fix a BPF verifier validation bug with may_goto combined with jump to
   the first instruction, also from Alexei Starovoitov.

3) Fix a bug with overrunning reservations in BPF ring buffer,
   from Daniel Borkmann.

4) Fix a bug in BPF verifier due to missing proper var_off setting related
   to movsx instruction, from Yonghong Song.

5) Silence unnecessary syzkaller-triggered warning in __xdp_reg_mem_model(),
   from Daniil Dulov.

* tag 'for-netdev' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  xdp: Remove WARN() from __xdp_reg_mem_model()
  selftests/bpf: Add tests for may_goto with negative offset.
  bpf: Fix may_goto with negative offset.
  selftests/bpf: Add more ring buffer test coverage
  bpf: Fix overrunning reservations in ringbuf
  selftests/bpf: Tests with may_goto and jumps to the 1st insn
  bpf: Fix the corner case with may_goto and jump to the 1st insn.
  bpf: Update BPF LSM maintainer list
  bpf: Fix remap of arena.
  selftests/bpf: Add a few tests to cover
  bpf: Add missed var_off setting in coerce_subreg_to_size_sx()
  bpf: Add missed var_off setting in set_sext32_default_val()
====================

Link: https://patch.msgid.link/20240624124330.8401-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-24 18:15:22 -07:00
Andrii Nakryiko
4a365eb8a6 perf,uprobes: fix user stack traces in the presence of pending uretprobes
When kernel has pending uretprobes installed, it hijacks original user
function return address on the stack with a uretprobe trampoline
address. There could be multiple such pending uretprobes (either on
different user functions or on the same recursive one) at any given
time within the same task.

This approach interferes with the user stack trace capture logic, which
would report suprising addresses (like 0x7fffffffe000) that correspond
to a special "[uprobes]" section that kernel installs in the target
process address space for uretprobe trampoline code, while logically it
should be an address somewhere within the calling function of another
traced user function.

This is easy to correct for, though. Uprobes subsystem keeps track of
pending uretprobes and records original return addresses. This patch is
using this to do a post-processing step and restore each trampoline
address entries with correct original return address. This is done only
if there are pending uretprobes for current task.

This is a similar approach to what fprobe/kretprobe infrastructure is
doing when capturing kernel stack traces in the presence of pending
return probes.

Link: https://lore.kernel.org/all/20240522013845.1631305-3-andrii@kernel.org/

Reported-by: Riham Selim <rihams@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-06-25 10:03:23 +09:00
Sebastian Andrzej Siewior
3f9fe37d9e net: Move per-CPU flush-lists to bpf_net_context on PREEMPT_RT.
The per-CPU flush lists, which are accessed from within the NAPI callback
(xdp_do_flush() for instance), are per-CPU. There are subject to the
same problem as struct bpf_redirect_info.

Add the per-CPU lists cpu_map_flush_list, dev_map_flush_list and
xskmap_map_flush_list to struct bpf_net_context. Add wrappers for the
access. The lists initialized on first usage (similar to
bpf_net_ctx_get_ri()).

Cc: "Björn Töpel" <bjorn@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20240620132727.660738-16-bigeasy@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-24 16:41:24 -07:00
Sebastian Andrzej Siewior
401cb7dae8 net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.
The XDP redirect process is two staged:
- bpf_prog_run_xdp() is invoked to run a eBPF program which inspects the
  packet and makes decisions. While doing that, the per-CPU variable
  bpf_redirect_info is used.

- Afterwards xdp_do_redirect() is invoked and accesses bpf_redirect_info
  and it may also access other per-CPU variables like xskmap_flush_list.

At the very end of the NAPI callback, xdp_do_flush() is invoked which
does not access bpf_redirect_info but will touch the individual per-CPU
lists.

The per-CPU variables are only used in the NAPI callback hence disabling
bottom halves is the only protection mechanism. Users from preemptible
context (like cpu_map_kthread_run()) explicitly disable bottom halves
for protections reasons.
Without locking in local_bh_disable() on PREEMPT_RT this data structure
requires explicit locking.

PREEMPT_RT has forced-threaded interrupts enabled and every
NAPI-callback runs in a thread. If each thread has its own data
structure then locking can be avoided.

Create a struct bpf_net_context which contains struct bpf_redirect_info.
Define the variable on stack, use bpf_net_ctx_set() to save a pointer to
it, bpf_net_ctx_clear() removes it again.
The bpf_net_ctx_set() may nest. For instance a function can be used from
within NET_RX_SOFTIRQ/ net_rx_action which uses bpf_net_ctx_set() and
NET_TX_SOFTIRQ which does not. Therefore only the first invocations
updates the pointer.
Use bpf_net_ctx_get_ri() as a wrapper to retrieve the current struct
bpf_redirect_info. The returned data structure is zero initialized to
ensure nothing is leaked from stack. This is done on first usage of the
struct. bpf_net_ctx_set() sets bpf_redirect_info::kern_flags to 0 to
note that initialisation is required. First invocation of
bpf_net_ctx_get_ri() will memset() the data structure and update
bpf_redirect_info::kern_flags.
bpf_redirect_info::nh is excluded from memset because it is only used
once BPF_F_NEIGH is set which also sets the nh member. The kern_flags is
moved past nh to exclude it from memset.

The pointer to bpf_net_context is saved task's task_struct. Using
always the bpf_net_context approach has the advantage that there is
almost zero differences between PREEMPT_RT and non-PREEMPT_RT builds.

Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20240620132727.660738-15-bigeasy@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-24 16:41:24 -07:00
Sebastian Andrzej Siewior
c5bcab7558 locking/local_lock: Add local nested BH locking infrastructure.
Add local_lock_nested_bh() locking. It is based on local_lock_t and the
naming follows the preempt_disable_nested() example.

For !PREEMPT_RT + !LOCKDEP it is a per-CPU annotation for locking
assumptions based on local_bh_disable(). The macro is optimized away
during compilation.
For !PREEMPT_RT + LOCKDEP the local_lock_nested_bh() is reduced to
the usual lock-acquire plus lockdep_assert_in_softirq() - ensuring that
BH is disabled.

For PREEMPT_RT local_lock_nested_bh() acquires the specified per-CPU
lock. It does not disable CPU migration because it relies on
local_bh_disable() disabling CPU migration.
With LOCKDEP it performans the usual lockdep checks as with !PREEMPT_RT.
Due to include hell the softirq check has been moved spinlock.c.

The intention is to use this locking in places where locking of a per-CPU
variable relies on BH being disabled. Instead of treating disabled
bottom halves as a big per-CPU lock, PREEMPT_RT can use this to reduce
the locking scope to what actually needs protecting.
A side effect is that it also documents the protection scope of the
per-CPU variables.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20240620132727.660738-3-bigeasy@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-24 16:41:22 -07:00