Commit Graph
35571 Commits
Author SHA1 Message Date
Thomas Gleixner 04b79c5520 futex: Replace pointless printk in fixup_owner()
If that unexpected case of inconsistent arguments ever happens then the
futex state is left completely inconsistent and the printk is not really
helpful. Replace it with a warning and make the state consistent.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:58 +01:00
Thomas Gleixner 12bb3f7f1b futex: Ensure the correct return value from futex_lock_pi()
In case that futex_lock_pi() was aborted by a signal or a timeout and the
task returned without acquiring the rtmutex, but is the designated owner of
the futex due to a concurrent futex_unlock_pi() fixup_owner() is invoked to
establish consistent state. In that case it invokes fixup_pi_state_owner()
which in turn tries to acquire the rtmutex again. If that succeeds then it
does not propagate this success to fixup_owner() and futex_lock_pi()
returns -EINTR or -ETIMEOUT despite having the futex locked.

Return success from fixup_pi_state_owner() in all cases where the current
task owns the rtmutex and therefore the futex and propagate it correctly
through fixup_owner(). Fixup the other callsite which does not expect a
positive return value.

Fixes: c1e2f0eaf0 ("futex: Avoid violating the 10th rule of futex")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
2021-01-26 15:10:58 +01:00
Linus Torvalds 007ad27d7b Merge tag 'printk-for-5.11-urgent-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk fix from Petr Mladek:
 "The fix of a potential buffer overflow in 5.11-rc5 introduced another
  one. The trailing '\0' might be written up to the message "len" past
  the buffer. Fortunately, it is not that easy to hit.

  Most readers use 1kB buffers for a single message. Typical messages
  fit into the temporary buffer with enough reserve.

  Also readers do not rely on the '\0'. It is related to the previous
  fix. Some readers required the space for the trailing '\0'. We decided
  to write it there to avoid such regressions in the future.

  The most realistic victims are dumpers using kmsg_dump_get_buffer().
  They are filling the entire buffer with as many messages as possible.
  They are typically used when handling panic()"

* tag 'printk-for-5.11-urgent-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: fix string termination for record_print_text()
2021-01-25 10:19:40 -08:00
Laurent Badel fef9c8d28e PM: hibernate: flush swap writer after marking
Flush the swap writer after, not before, marking the files, to ensure the
signature is properly written.

Fixes: 6f612af578 ("PM / Hibernate: Group swap ops")
Signed-off-by: Laurent Badel <laurentbadel@eaton.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 18:52:30 +01:00
Baoquan He 56c91a1843 kernel: kexec: remove the lock operation of system_transition_mutex
Function kernel_kexec() is called with lock system_transition_mutex
held in reboot system call. While inside kernel_kexec(), it will
acquire system_transition_mutex agin. This will lead to dead lock.

The dead lock should be easily triggered, it hasn't caused any
failure report just because the feature 'kexec jump' is almost not
used by anyone as far as I know. An inquiry can be made about who
is using 'kexec jump' and where it's used. Before that, let's simply
remove the lock operation inside CONFIG_KEXEC_JUMP ifdeffery scope.

Fixes: 55f2503c3b ("PM / reboot: Eliminate race between reboot and suspend")
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Pingfan Liu <kernelfans@gmail.com>
Cc: 4.19+ <stable@vger.kernel.org> # 4.19+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 18:40:37 +01:00
Petr Mladek 61bb17da44 Merge branch 'printk-rework' into for-linus 2021-01-25 14:29:35 +01:00
John Ogness 08d60e5999 printk: fix string termination for record_print_text()
Commit f0e386ee0c ("printk: fix buffer overflow potential for
print_text()") added string termination in record_print_text().
However it used the wrong base pointer for adding the terminator.
This led to a 0-byte being written somewhere beyond the buffer.

Use the correct base pointer when adding the terminator.

Fixes: f0e386ee0c ("printk: fix buffer overflow potential for print_text()")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210124202728.4718-1-john.ogness@linutronix.de
2021-01-25 10:37:08 +01:00
Christoph Hellwig 309dca309f block: store a block_device pointer in struct bio
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device.  From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24 18:17:20 -07:00
Linus Torvalds e68061375f Merge tag 'irq_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Borislav Petkov:

 - Fix a kernel panic in mips-cpu due to invalid irq domain hierarchy.

 - Fix to not lose IPIs on bcm2836.

 - Fix for a bogus marking of ITS devices as shared due to unitialized
   stack variable.

 - Clear a phantom interrupt on qcom-pdc to unblock suspend.

 - Small cleanups, warning and build fixes.

* tag 'irq_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Export irq_check_status_bit()
  irqchip/mips-cpu: Set IPI domain parent chip
  irqchip/pruss: Simplify the TI_PRUSS_INTC Kconfig
  irqchip/loongson-liointc: Fix build warnings
  driver core: platform: Add extra error check in devm_platform_get_irqs_affinity()
  irqchip/bcm2836: Fix IPI acknowledgement after conversion to handle_percpu_devid_irq
  irqchip/irq-sl28cpld: Convert comma to semicolon
  genirq/msi: Initialize msi_alloc_info before calling msi_domain_prepare_irqs()
2021-01-24 10:24:20 -08:00
Linus Torvalds 24c56ee06c Merge tag 'sched_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Borislav Petkov:

 - Correct the marking of kthreads which are supposed to run on a
   specific, single CPU vs such which are affine to only one CPU, mark
   per-cpu workqueue threads as such and make sure that marking
   "survives" CPU hotplug. Fix CPU hotplug issues with such kthreads.

 - A fix to not push away tasks on CPUs coming online.

 - Have workqueue CPU hotplug code use cpu_possible_mask when breaking
   affinity on CPU offlining so that pending workers can finish on newly
   arrived onlined CPUs too.

 - Dump tasks which haven't vacated a CPU which is currently being
   unplugged.

 - Register a special scale invariance callback which gets called on
   resume from RAM to read out APERF/MPERF after resume and thus make
   the schedutil scaling governor more precise.

* tag 'sched_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Relax the set_cpus_allowed_ptr() semantics
  sched: Fix CPU hotplug / tighten is_per_cpu_kthread()
  sched: Prepare to use balance_push in ttwu()
  workqueue: Restrict affinity change to rescuer
  workqueue: Tag bound workers with KTHREAD_IS_PER_CPU
  kthread: Extract KTHREAD_IS_PER_CPU
  sched: Don't run cpu-online with balance_push() enabled
  workqueue: Use cpu_possible_mask instead of cpu_active_mask to break affinity
  sched/core: Print out straggler tasks in sched_cpu_dying()
  x86: PM: Register syscore_ops for scale invariance
2021-01-24 10:09:20 -08:00
Linus Torvalds 025929f468 Merge tag 'timers_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Borislav Petkov:

 - Fix an integer overflow in the NTP RTC synchronization which led to
   the latter happening every 2 seconds instead of the intended every 11
   minutes.

 - Get rid of now unused get_seconds().

* tag 'timers_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ntp: Fix RTC synchronization on 32-bit platforms
  timekeeping: Remove unused get_seconds()
2021-01-24 09:58:38 -08:00
Linus Torvalds 17b6c49da3 Merge tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:

 - Add a new Intel model number for Alder Lake

 - Differentiate which aspects of the FPU state get saved/restored when
   the FPU is used in-kernel and fix a boot crash on K7 due to early
   MXCSR access before CR4.OSFXSR is even set.

 - A couple of noinstr annotation fixes

 - Correct die ID setting on AMD for users of topology information which
   need the correct die ID

 - A SEV-ES fix to handle string port IO to/from kernel memory properly

* tag 'x86_urgent_for_v5.11_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Add another Alder Lake CPU to the Intel family
  x86/mmx: Use KFPU_387 for MMX string operations
  x86/fpu: Add kernel_fpu_begin_mask() to selectively initialize state
  x86/topology: Make __max_die_per_package available unconditionally
  x86: __always_inline __{rd,wr}msr()
  x86/mce: Remove explicit/superfluous tracing
  locking/lockdep: Avoid noinstr warning for DEBUG_LOCKDEP
  locking/lockdep: Cure noinstr fail
  x86/sev: Fix nonistr violation
  x86/entry: Fix noinstr fail
  x86/cpu/amd: Set __max_die_per_package on AMD
  x86/sev-es: Handle string port IO to kernel memory properly
2021-01-24 09:46:05 -08:00
Linus Torvalds c509ce2378 Merge tag 'for-linus-2021-01-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull misc fixes from Christian Brauner:

 - Jann reported sparse complaints because of a missing __user
   annotation in a helper we added way back when we added
   pidfd_send_signal() to avoid compat syscall handling. Fix it.

 - Yanfei replaces a reference in a comment to the _do_fork() helper I
   removed a while ago with a reference to the new kernel_clone()
   replacement

 - Alexander Guril added a simple coding style fix

* tag 'for-linus-2021-01-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  kthread: remove comments about old _do_fork() helper
  Kernel: fork.c: Fix coding style: Do not use {} around single-line statements
  signal: Add missing __user annotation to copy_siginfo_from_user_any
2021-01-24 09:35:28 -08:00
Paul E. McKenney 0d2460ba61 Merge branches 'doc.2021.01.06a', 'fixes.2021.01.04b', 'kfree_rcu.2021.01.04a', 'mmdumpobj.2021.01.22a', 'nocb.2021.01.06a', 'rt.2021.01.04a', 'stall.2021.01.06a', 'torture.2021.01.12a' and 'tortureall.2021.01.06a' into HEAD
doc.2021.01.06a: Documentation updates.
fixes.2021.01.04b: Miscellaneous fixes.
kfree_rcu.2021.01.04a: kfree_rcu() updates.
mmdumpobj.2021.01.22a: Dump allocation point for memory blocks.
nocb.2021.01.06a: RCU callback offload updates and cblist segment lengths.
rt.2021.01.04a: Real-time updates.
stall.2021.01.06a: RCU CPU stall warning updates.
torture.2021.01.12a: Torture-test updates and polling SRCU grace-period API.
tortureall.2021.01.06a: Torture-test script updates.
2021-01-22 15:26:44 -08:00
Paul E. McKenney b4b7914a6a rcu: Make call_rcu() print mem_dump_obj() info for double-freed callback
The debug-object double-free checks in __call_rcu() print out the
RCU callback function, which is usually sufficient to track down the
double free.  However, all uses of things like queue_rcu_work() will
have the same RCU callback function (rcu_work_rcufn() in this case),
so a diagnostic message for a double queue_rcu_work() needs more than
just the callback function.

This commit therefore calls mem_dump_obj() to dump out any additional
available information on the double-freed callback.

Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <linux-mm@kvack.org>
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-01-22 15:24:16 -08:00
Tobias Klauser 18b24d78d5 bpf: Fix typo in scalar{,32}_min_max_rsh comments
s/bounts/bounds/

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210121174324.24127-1-tklauser@distanz.ch
2021-01-23 00:23:23 +01:00
Pan Bian b9557caaf8 bpf, inode_storage: Put file handler if no storage was found
Put file f if inode_storage_ptr() returns NULL.

Fixes: 8ea636848a ("bpf: Implement bpf_local_storage for inodes")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/bpf/20210121020856.25507-1-bianpan2016@163.com
2021-01-22 23:19:24 +01:00
Loris Reiff f4a2da755a bpf, cgroup: Fix problematic bounds check
Since ctx.optlen is signed, a larger value than max_value could be
passed, as it is later on used as unsigned, which causes a WARN_ON_ONCE
in the copy_to_user.

Fixes: 0d01da6afc ("bpf: implement getsockopt and setsockopt hooks")
Signed-off-by: Loris Reiff <loris.reiff@liblor.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20210122164232.61770-2-loris.reiff@liblor.ch
2021-01-22 23:11:47 +01:00
Loris Reiff bb8b81e396 bpf, cgroup: Fix optlen WARN_ON_ONCE toctou
A toctou issue in `__cgroup_bpf_run_filter_getsockopt` can trigger a
WARN_ON_ONCE in a check of `copy_from_user`.

`*optlen` is checked to be non-negative in the individual getsockopt
functions beforehand. Changing `*optlen` in a race to a negative value
will result in a `copy_from_user(ctx.optval, optval, ctx.optlen)` with
`ctx.optlen` being a negative integer.

Fixes: 0d01da6afc ("bpf: implement getsockopt and setsockopt hooks")
Signed-off-by: Loris Reiff <loris.reiff@liblor.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20210122164232.61770-1-loris.reiff@liblor.ch
2021-01-22 23:11:34 +01:00
Peter Zijlstra 741ba80f6f sched: Relax the set_cpus_allowed_ptr() semantics
Now that we have KTHREAD_IS_PER_CPU to denote the critical per-cpu
tasks to retain during CPU offline, we can relax the warning in
set_cpus_allowed_ptr(). Any spurious kthread that wants to get on at
the last minute will get pushed off before it can run.

While during CPU online there is no harm, and actual benefit, to
allowing kthreads back on early, it simplifies hotplug code and fixes
a number of outstanding races.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Lai jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103507.240724591@infradead.org
2021-01-22 15:09:44 +01:00
Peter Zijlstra 5ba2ffba13 sched: Fix CPU hotplug / tighten is_per_cpu_kthread()
Prior to commit 1cf12e08bc ("sched/hotplug: Consolidate task
migration on CPU unplug") we'd leave any task on the dying CPU and
break affinity and force them off at the very end.

This scheme had to change in order to enable migrate_disable(). One
cannot wait for migrate_disable() to complete while stuck in
stop_machine(). Furthermore, since we need at the very least: idle,
hotplug and stop threads at any point before stop_machine, we can't
break affinity and/or push those away.

Under the assumption that all per-cpu kthreads are sanely handled by
CPU hotplug, the new code no long breaks affinity or migrates any of
them (which then includes the critical ones above).

However, there's an important difference between per-cpu kthreads and
kthreads that happen to have a single CPU affinity which is lost. The
latter class very much relies on the forced affinity breaking and
migration semantics previously provided.

Use the new kthread_is_per_cpu() infrastructure to tighten
is_per_cpu_kthread() and fix the hot-unplug problems stemming from the
change.

Fixes: 1cf12e08bc ("sched/hotplug: Consolidate task migration on CPU unplug")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103507.102416009@infradead.org
2021-01-22 15:09:44 +01:00
Peter Zijlstra 975707f227 sched: Prepare to use balance_push in ttwu()
In preparation of using the balance_push state in ttwu() we need it to
provide a reliable and consistent state.

The immediate problem is that rq->balance_callback gets cleared every
schedule() and then re-set in the balance_push_callback() itself. This
is not a reliable signal, so add a variable that stays set during the
entire time.

Also move setting it before the synchronize_rcu() in
sched_cpu_deactivate(), such that we get guaranteed visibility to
ttwu(), which is a preempt-disable region.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.966069627@infradead.org
2021-01-22 15:09:43 +01:00
Peter Zijlstra 640f17c824 workqueue: Restrict affinity change to rescuer
create_worker() will already set the right affinity using
kthread_bind_mask(), this means only the rescuer will need to change
it's affinity.

Howveer, while in cpu-hot-unplug a regular task is not allowed to run
on online&&!active as it would be pushed away quite agressively. We
need KTHREAD_IS_PER_CPU to survive in that environment.

Therefore set the affinity after getting that magic flag.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.826629830@infradead.org
2021-01-22 15:09:43 +01:00
Peter Zijlstra 5c25b5ff89 workqueue: Tag bound workers with KTHREAD_IS_PER_CPU
Mark the per-cpu workqueue workers as KTHREAD_IS_PER_CPU.

Workqueues have unfortunate semantics in that per-cpu workers are not
default flushed and parked during hotplug, however a subset does
manual flush on hotplug and hard relies on them for correctness.

Therefore play silly games..

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.693465814@infradead.org
2021-01-22 15:09:42 +01:00
Peter Zijlstra ac687e6e8c kthread: Extract KTHREAD_IS_PER_CPU
There is a need to distinguish geniune per-cpu kthreads from kthreads
that happen to have a single CPU affinity.

Geniune per-cpu kthreads are kthreads that are CPU affine for
correctness, these will obviously have PF_KTHREAD set, but must also
have PF_NO_SETAFFINITY set, lest userspace modify their affinity and
ruins things.

However, these two things are not sufficient, PF_NO_SETAFFINITY is
also set on other tasks that have their affinities controlled through
other means, like for instance workqueues.

Therefore another bit is needed; it turns out kthread_create_per_cpu()
already has such a bit: KTHREAD_IS_PER_CPU, which is used to make
kthread_park()/kthread_unpark() work correctly.

Expose this flag and remove the implicit setting of it from
kthread_create_on_cpu(); the io_uring usage of it seems dubious at
best.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.557620262@infradead.org
2021-01-22 15:09:42 +01:00
Peter Zijlstra 22f667c97a sched: Don't run cpu-online with balance_push() enabled
We don't need to push away tasks when we come online, mark the push
complete right before the CPU dies.

XXX hotplug state machine has trouble with rollback here.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.415606087@infradead.org
2021-01-22 15:09:42 +01:00
Lai Jiangshan 547a77d02f workqueue: Use cpu_possible_mask instead of cpu_active_mask to break affinity
The scheduler won't break affinity for us any more, and we should
"emulate" the same behavior when the scheduler breaks affinity for
us.  The behavior is "changing the cpumask to cpu_possible_mask".

And there might be some other CPUs online later while the worker is
still running with the pending work items.  The worker should be allowed
to use the later online CPUs as before and process the work items ASAP.
If we use cpu_active_mask here, we can't achieve this goal but
using cpu_possible_mask can.

Fixes: 06249738a4 ("workqueue: Manually break affinity on hotplug")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210111152638.2417-4-jiangshanlai@gmail.com
2021-01-22 15:09:41 +01:00
Valentin Schneider 36c6e17bf1 sched/core: Print out straggler tasks in sched_cpu_dying()
Since commit

  1cf12e08bc ("sched/hotplug: Consolidate task migration on CPU unplug")

tasks are expected to move themselves out of a out-going CPU. For most
tasks this will be done automagically via BALANCE_PUSH, but percpu kthreads
will have to cooperate and move themselves away one way or another.

Currently, some percpu kthreads (workqueues being a notable exemple) do not
cooperate nicely and can end up on an out-going CPU at the time
sched_cpu_dying() is invoked.

Print the dying rq's tasks to shed some light on the stragglers.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210113183141.11974-1-valentin.schneider@arm.com
2021-01-22 15:09:41 +01:00
Mark Rutland 997acaf6b4 lockdep: report broken irq restoration
We generally expect local_irq_save() and local_irq_restore() to be
paired and sanely nested, and so local_irq_restore() expects to be
called with irqs disabled. Thus, within local_irq_restore() we only
trace irq flag changes when unmasking irqs.

This means that a sequence such as:

| local_irq_disable();
| local_irq_save(flags);
| local_irq_enable();
| local_irq_restore(flags);

... is liable to break things, as the local_irq_restore() would mask
irqs without tracing this change. Similar problems may exist for
architectures whose arch_irq_restore() function depends on being called
with irqs disabled.

We don't consider such sequences to be a good idea, so let's define
those as forbidden, and add tooling to detect such broken cases.

This patch adds debug code to WARN() when raw_local_irq_restore() is
called with irqs enabled. As raw_local_irq_restore() is expected to pair
with raw_local_irq_save(), it should never be called with irqs enabled.

To avoid the possibility of circular header dependencies between
irqflags.h and bug.h, the warning is handled in a separate C file.

The new code is all conditional on a new CONFIG_DEBUG_IRQFLAGS symbol
which is independent of CONFIG_TRACE_IRQFLAGS. As noted above such cases
will confuse lockdep, so CONFIG_DEBUG_LOCKDEP now selects
CONFIG_DEBUG_IRQFLAGS.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210111153707.10071-1-mark.rutland@arm.com
2021-01-22 11:08:56 +01:00
Linus Torvalds 2561bbbe2e Merge tag 'printk-for-5.11-printk-rework-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk fixes from Petr Mladek:

 - Fix line counting and buffer size calculation. Both regressions
   caused that a reader buffer might not get filled as much as possible.

 - Restore non-documented behavior of printk() reader API and make it
   official.

   It did not fill the last byte of the provided buffer before 5.10. Two
   architectures, powerpc and um, used it to add the trailing '\0'.
   There might theoretically be more callers depending on this behavior
   in userspace.

* tag 'printk-for-5.11-printk-rework-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: fix buffer overflow potential for print_text()
  printk: fix kmsg_dump_get_buffer length calulations
  printk: ringbuffer: fix line counting
2021-01-21 11:37:22 -08:00
Petr Mladek 535b6a122c Merge branch 'printk-rework' into for-linus 2021-01-21 16:06:21 +01:00
Stanislav Fomichev a9ed15dae0 bpf: Split cgroup_bpf_enabled per attach type
When we attach any cgroup hook, the rest (even if unused/unattached) start
to contribute small overhead. In particular, the one we want to avoid is
__cgroup_bpf_run_filter_skb which does two redirections to get to
the cgroup and pushes/pulls skb.

Let's split cgroup_bpf_enabled to be per-attach to make sure
only used attach types trigger.

I've dropped some existing high-level cgroup_bpf_enabled in some
places because BPF_PROG_CGROUP_XXX_RUN macros usually have another
cgroup_bpf_enabled check.

I also had to copy-paste BPF_CGROUP_RUN_SA_PROG_LOCK for
GETPEERNAME/GETSOCKNAME because type for cgroup_bpf_enabled[type]
has to be constant and known at compile time.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-4-sdf@google.com
2021-01-20 14:23:00 -08:00
Stanislav Fomichev 20f2505fb4 bpf: Try to avoid kzalloc in cgroup/{s,g}etsockopt
When we attach a bpf program to cgroup/getsockopt any other getsockopt()
syscall starts incurring kzalloc/kfree cost.

Let add a small buffer on the stack and use it for small (majority)
{s,g}etsockopt values. The buffer is small enough to fit into
the cache line and cover the majority of simple options (most
of them are 4 byte ints).

It seems natural to do the same for setsockopt, but it's a bit more
involved when the BPF program modifies the data (where we have to
kmalloc). The assumption is that for the majority of setsockopt
calls (which are doing pure BPF options or apply policy) this
will bring some benefit as well.

Without this patch (we remove about 1% __kmalloc):
     3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
            |
             --3.30%--__cgroup_bpf_run_filter_getsockopt
                       |
                        --0.81%--__kmalloc

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-3-sdf@google.com
2021-01-20 14:23:00 -08:00
Stanislav Fomichev 9cacf81f81 bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE
Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE.
We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom
call in do_tcp_getsockopt using the on-stack data. This removes
3% overhead for locking/unlocking the socket.

Without this patch:
     3.38%     0.07%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt
            |
             --3.30%--__cgroup_bpf_run_filter_getsockopt
                       |
                        --0.81%--__kmalloc

With the patch applied:
     0.52%     0.12%  tcp_mmap  [kernel.kallsyms]  [k] __cgroup_bpf_run_filter_getsockopt_kern

Note, exporting uapi/tcp.h requires removing netinet/tcp.h
from test_progs.h because those headers have confliciting
definitions.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-2-sdf@google.com
2021-01-20 14:23:00 -08:00
Yonghong Song 13ca51d5eb bpf: Permit size-0 datasec
llvm patch https://reviews.llvm.org/D84002 permitted
to emit empty rodata datasec if the elf .rodata section
contains read-only data from local variables. These
local variables will be not emitted as BTF_KIND_VARs
since llvm converted these local variables as
static variables with private linkage without debuginfo
types. Such an empty rodata datasec will make
skeleton code generation easy since for skeleton
a rodata struct will be generated if there is a
.rodata elf section. The existence of a rodata
btf datasec is also consistent with the existence
of a rodata map created by libbpf.

The btf with such an empty rodata datasec will fail
in the kernel though as kernel will reject a datasec
with zero vlen and zero size. For example, for the below code,
    int sys_enter(void *ctx)
    {
       int fmt[6] = {1, 2, 3, 4, 5, 6};
       int dst[6];

       bpf_probe_read(dst, sizeof(dst), fmt);
       return 0;
    }
We got the below btf (bpftool btf dump ./test.o):
    [1] PTR '(anon)' type_id=0
    [2] FUNC_PROTO '(anon)' ret_type_id=3 vlen=1
            'ctx' type_id=1
    [3] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED
    [4] FUNC 'sys_enter' type_id=2 linkage=global
    [5] INT 'char' size=1 bits_offset=0 nr_bits=8 encoding=SIGNED
    [6] ARRAY '(anon)' type_id=5 index_type_id=7 nr_elems=4
    [7] INT '__ARRAY_SIZE_TYPE__' size=4 bits_offset=0 nr_bits=32 encoding=(none)
    [8] VAR '_license' type_id=6, linkage=global-alloc
    [9] DATASEC '.rodata' size=0 vlen=0
    [10] DATASEC 'license' size=0 vlen=1
            type_id=8 offset=0 size=4
When loading the ./test.o to the kernel with bpftool,
we see the following error:
    libbpf: Error loading BTF: Invalid argument(22)
    libbpf: magic: 0xeb9f
    ...
    [6] ARRAY (anon) type_id=5 index_type_id=7 nr_elems=4
    [7] INT __ARRAY_SIZE_TYPE__ size=4 bits_offset=0 nr_bits=32 encoding=(none)
    [8] VAR _license type_id=6 linkage=1
    [9] DATASEC .rodata size=24 vlen=0 vlen == 0
    libbpf: Error loading .BTF into kernel: -22. BTF is optional, ignoring.

Basically, libbpf changed .rodata datasec size to 24 since elf .rodata
section size is 24. The kernel then rejected the BTF since vlen = 0.
Note that the above kernel verifier failure can be worked around with
changing local variable "fmt" to a static or global, optionally const, variable.

This patch permits a datasec with vlen = 0 in kernel.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210119153519.3901963-1-yhs@fb.com
2021-01-20 14:14:09 -08:00
Lorenzo Bianconi 97a0e1ea7b net, xdp: Introduce __xdp_build_skb_from_frame utility routine
Introduce __xdp_build_skb_from_frame utility routine to build
the skb from xdp_frame. Rely on __xdp_build_skb_from_frame in
cpumap code.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/4f9f4c6b3dd3933770c617eb6689dbc0c6e25863.1610475660.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-01-20 14:10:35 -08:00
Jakub Kicinski 0fe2f273ab Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/can/dev.c
  commit 03f16c5075 ("can: dev: can_restart: fix use after free bug")
  commit 3e77f70e73 ("can: dev: move driver related infrastructure into separate subdir")

  Code move.

drivers/net/dsa/b53/b53_common.c
 commit 8e4052c32d ("net: dsa: b53: fix an off by one in checking "vlan->vid"")
 commit b7a9e0da2d ("net: switchdev: remove vid_begin -> vid_end range from VLAN objects")

 Field rename.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20 12:16:11 -08:00
Linus Torvalds 75439bc439 Merge tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.11-rc5, including fixes from bpf, wireless, and
  can trees.

  Current release - regressions:

   - nfc: nci: fix the wrong NCI_CORE_INIT parameters

  Current release - new code bugs:

   - bpf: allow empty module BTFs

  Previous releases - regressions:

   - bpf: fix signed_{sub,add32}_overflows type handling

   - tcp: do not mess with cloned skbs in tcp_add_backlog()

   - bpf: prevent double bpf_prog_put call from bpf_tracing_prog_attach

   - bpf: don't leak memory in bpf getsockopt when optlen == 0

   - tcp: fix potential use-after-free due to double kfree()

   - mac80211: fix encryption issues with WEP

   - devlink: use right genl user_ptr when handling port param get/set

   - ipv6: set multicast flag on the multicast route

   - tcp: fix TCP_USER_TIMEOUT with zero window

  Previous releases - always broken:

   - bpf: local storage helpers should check nullness of owner ptr passed

   - mac80211: fix incorrect strlen of .write in debugfs

   - cls_flower: call nla_ok() before nla_next()

   - skbuff: back tiny skbs with kmalloc() in __netdev_alloc_skb() too"

* tag 'net-5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (52 commits)
  net: systemport: free dev before on error path
  net: usb: cdc_ncm: don't spew notifications
  net: mscc: ocelot: Fix multicast to the CPU port
  tcp: Fix potential use-after-free due to double kfree()
  bpf: Fix signed_{sub,add32}_overflows type handling
  can: peak_usb: fix use after free bugs
  can: vxcan: vxcan_xmit: fix use after free bug
  can: dev: can_restart: fix use after free bug
  tcp: fix TCP socket rehash stats mis-accounting
  net: dsa: b53: fix an off by one in checking "vlan->vid"
  tcp: do not mess with cloned skbs in tcp_add_backlog()
  selftests: net: fib_tests: remove duplicate log test
  net: nfc: nci: fix the wrong NCI_CORE_INIT parameters
  sh_eth: Fix power down vs. is_opened flag ordering
  net: Disable NETIF_F_HW_TLS_RX when RXCSUM is disabled
  netfilter: rpfilter: mask ecn bits before fib lookup
  udp: mask TOS bits in udp_v4_early_demux()
  xsk: Clear pool even for inactive queues
  bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback
  sh_eth: Make PHY access aware of Runtime PM to fix reboot crash
  ...
2021-01-20 11:52:21 -08:00
Daniel Borkmann bc895e8b2a bpf: Fix signed_{sub,add32}_overflows type handling
Fix incorrect signed_{sub,add32}_overflows() input types (and a related buggy
comment). It looks like this might have slipped in via copy/paste issue, also
given prior to 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
the signature of signed_sub_overflows() had s64 a and s64 b as its input args
whereas now they are truncated to s32. Thus restore proper types. Also, the case
of signed_add32_overflows() is not consistent to signed_sub32_overflows(). Both
have s32 as inputs, therefore align the former.

Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: De4dCr0w <sa516203@mail.ustc.edu.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-01-20 17:19:40 +01:00
Linus Torvalds 45dfb8a565 Merge tag 'task_work-2021-01-19' of git://git.kernel.dk/linux-block
Pull task_work fix from Jens Axboe:
 "The TIF_NOTIFY_SIGNAL change inadvertently removed the unconditional
  task_work run we had in get_signal().

  This caused a regression for some setups, since we're relying on eg
  ____fput() being run to close and release, for example, a pipe and
  wake the other end.

  For 5.11, I prefer the simple solution of just reinstating the
  unconditional run, even if it conceptually doesn't make much sense -
  if you need that kind of guarantee, you should be using TWA_SIGNAL
  instead of TWA_NOTIFY. But it's the trivial fix for 5.11, and would
  ensure that other potential gotchas/assumptions for task_work don't
  regress for 5.11.

  We're looking into further simplifying the task_work notifications for
  5.12 which would resolve that too"

* tag 'task_work-2021-01-19' of git://git.kernel.dk/linux-block:
  task_work: unconditionally run task_work from get_signal()
2021-01-19 13:26:05 -08:00
Mircea Cirjaliu 301a33d518 bpf: Fix helper bpf_map_peek_elem_proto pointing to wrong callback
I assume this was obtained by copy/paste. Point it to bpf_map_peek_elem()
instead of bpf_map_pop_elem(). In practice it may have been less likely
hit when under JIT given shielded via 84430d4232 ("bpf, verifier: avoid
retpoline for map push/pop/peek operation").

Fixes: f1a2e44a3a ("bpf: add queue and stack maps")
Signed-off-by: Mircea Cirjaliu <mcirjaliu@bitdefender.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Mauricio Vasquez <mauriciovasquezbernal@gmail.com>
Link: https://lore.kernel.org/bpf/AM7PR02MB6082663DFDCCE8DA7A6DD6B1BBA30@AM7PR02MB6082.eurprd02.prod.outlook.com
2021-01-19 22:04:08 +01:00
Odin Ugedal 385aac1519 cgroup: fix psi monitor for root cgroup
Fix NULL pointer dereference when adding new psi monitor to the root
cgroup. PSI files for root cgroup was introduced in df5ba5be74 by using
system wide psi struct when reading, but file write/monitor was not
properly fixed. Since the PSI config for the root cgroup isn't
initialized, the current implementation tries to lock a NULL ptr,
resulting in a crash.

Can be triggered by running this as root:
$ tee /sys/fs/cgroup/cpu.pressure <<< "some 10000 1000000"

Signed-off-by: Odin Ugedal <odin@uged.al>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Dan Schatzberg <dschatzberg@fb.com>
Fixes: df5ba5be74 ("kernel/sched/psi.c: expose pressure metrics on root cgroup")
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: stable@vger.kernel.org # 5.2+
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-19 11:37:05 -05:00
John Ogness f0e386ee0c printk: fix buffer overflow potential for print_text()
Before the commit 896fbe20b4 ("printk: use the lockless
ringbuffer"), msg_print_text() would only write up to size-1 bytes
into the provided buffer. Some callers expect this behavior and
append a terminator to returned string. In particular:

arch/powerpc/xmon/xmon.c:dump_log_buf()
arch/um/kernel/kmsg_dump.c:kmsg_dumper_stdout()

msg_print_text() has been replaced by record_print_text(), which
currently fills the full size of the buffer. This causes a
buffer overflow for the above callers.

Change record_print_text() so that it will only use size-1 bytes
for text data. Also, for paranoia sakes, add a terminator after
the text data.

And finally, document this behavior so that it is clear that only
size-1 bytes are used and a terminator is added.

Fixes: 896fbe20b4 ("printk: use the lockless ringbuffer")
Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210114170412.4819-1-john.ogness@linutronix.de
2021-01-19 11:42:14 +01:00
Jakub Kicinski 2d9116be76 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2021-01-16

1) Extend atomic operations to the BPF instruction set along with x86-64 JIT support,
   that is, atomic{,64}_{xchg,cmpxchg,fetch_{add,and,or,xor}}, from Brendan Jackman.

2) Add support for using kernel module global variables (__ksym externs in BPF
   programs) retrieved via module's BTF, from Andrii Nakryiko.

3) Generalize BPF stackmap's buildid retrieval and add support to have buildid
   stored in mmap2 event for perf, from Jiri Olsa.

4) Various fixes for cross-building BPF sefltests out-of-tree which then will
   unblock wider automated testing on ARM hardware, from Jean-Philippe Brucker.

5) Allow to retrieve SOL_SOCKET opts from sock_addr progs, from Daniel Borkmann.

6) Clean up driver's XDP buffer init and split into two helpers to init per-
   descriptor and non-changing fields during processing, from Lorenzo Bianconi.

7) Minor misc improvements to libbpf & bpftool, from Ian Rogers.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (41 commits)
  perf: Add build id data in mmap2 event
  bpf: Add size arg to build_id_parse function
  bpf: Move stack_map_get_build_id into lib
  bpf: Document new atomic instructions
  bpf: Add tests for new BPF atomic operations
  bpf: Add bitwise atomic instructions
  bpf: Pull out a macro for interpreting atomic ALU operations
  bpf: Add instructions for atomic_[cmp]xchg
  bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
  bpf: Move BPF_STX reserved field check into BPF_STX verifier code
  bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
  bpf: x86: Factor out a lookup table for some ALU opcodes
  bpf: x86: Factor out emission of REX byte
  bpf: x86: Factor out emission of ModR/M for *(reg + off)
  tools/bpftool: Add -Wall when building BPF programs
  bpf, libbpf: Avoid unused function warning on bpf_tail_call_static
  selftests/bpf: Install btf_dump test cases
  selftests/bpf: Fix installation of urandom_read
  selftests/bpf: Move generated test files to $(TEST_GEN_FILES)
  selftests/bpf: Fix out-of-tree build
  ...
====================

Link: https://lore.kernel.org/r/20210116012922.17823-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15 17:57:26 -08:00
Jakub Kicinski e23a8d0021 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2021-01-16

1) Fix a double bpf_prog_put() for BPF_PROG_{TYPE_EXT,TYPE_TRACING} types in
   link creation's error path causing a refcount underflow, from Jiri Olsa.

2) Fix BTF validation errors for the case where kernel modules don't declare
   any new types and end up with an empty BTF, from Andrii Nakryiko.

3) Fix BPF local storage helpers to first check their {task,inode} owners for
   being NULL before access, from KP Singh.

4) Fix a memory leak in BPF setsockopt handling for the case where optlen is
   zero and thus temporary optval buffer should be freed, from Stanislav Fomichev.

5) Fix a syzbot memory allocation splat in BPF_PROG_TEST_RUN infra for
   raw_tracepoint caused by too big ctx_size_in, from Song Liu.

6) Fix LLVM code generation issues with verifier where PTR_TO_MEM{,_OR_NULL}
   registers were spilled to stack but not recognized, from Gilad Reti.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  MAINTAINERS: Update my email address
  selftests/bpf: Add verifier test for PTR_TO_MEM spill
  bpf: Support PTR_TO_MEM{,_OR_NULL} register spilling
  bpf: Reject too big ctx_size_in for raw_tp test run
  libbpf: Allow loading empty BTFs
  bpf: Allow empty module BTFs
  bpf: Don't leak memory in bpf getsockopt when optlen == 0
  bpf: Update local storage test to check handling of null ptrs
  bpf: Fix typo in bpf_inode_storage.c
  bpf: Local storage helpers should check nullness of owner ptr passed
  bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach
====================

Link: https://lore.kernel.org/r/20210116002025.15706-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-15 16:34:59 -08:00
Chen Zhou 61e960b07b cgroup-v1: add disabled controller check in cgroup1_parse_param()
When mounting a cgroup hierarchy with disabled controller in cgroup v1,
all available controllers will be attached.
For example, boot with cgroup_no_v1=cpu or cgroup_disable=cpu, and then
mount with "mount -t cgroup -ocpu cpu /sys/fs/cgroup/cpu", then all
enabled controllers will be attached except cpu.

Fix this by adding disabled controller check in cgroup1_parse_param().
If the specified controller is disabled, just return error with information
"Disabled controller xx" rather than attaching all the other enabled
controllers.

Fixes: f5dfb5315d ("cgroup: take options parsing into ->parse_monolithic()")
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Reviewed-by: Zefan Li <lizefan.x@bytedance.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2021-01-15 15:10:37 -05:00
John Ogness 89ccf18f03 printk: fix kmsg_dump_get_buffer length calulations
kmsg_dump_get_buffer() uses @syslog to determine if the syslog
prefix should be written to the buffer. However, when calculating
the maximum number of records that can fit into the buffer, it
always counts the bytes from the syslog prefix.

Use @syslog when calculating the maximum number of records that can
fit into the buffer.

Fixes: e2ae715d66 ("kmsg - kmsg_dump() use iterator to receive log buffer content")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113164413.1599-1-john.ogness@linutronix.de
2021-01-15 11:32:52 +01:00
John Ogness 668af87f99 printk: ringbuffer: fix line counting
Counting text lines in a record simply involves counting the number
of newline characters (+1). However, it is searching the full data
block for newline characters, even though the text data can be (and
often is) a subset of that area. Since the extra area in the data
block was never initialized, the result is that extra newlines may
be seen and counted.

Restrict newline searching to the text data length.

Fixes: b6cf8b3f33 ("printk: add lockless ringbuffer")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113144234.6545-1-john.ogness@linutronix.de
2021-01-15 11:30:03 +01:00
Jiri Olsa 88a16a1309 perf: Add build id data in mmap2 event
Adding support to carry build id data in mmap2 event.

The build id data replaces maj/min/ino/ino_generation
fields, which are also used to identify map's binary,
so it's ok to replace them with build id data:

  union {
          struct {
                  u32       maj;
                  u32       min;
                  u64       ino;
                  u64       ino_generation;
          };
          struct {
                  u8        build_id_size;
                  u8        __reserved_1;
                  u16       __reserved_2;
                  u8        build_id[20];
          };
  };

Replaced maj/min/ino/ino_generation fields give us size
of 24 bytes. We use 20 bytes for build id data, 1 byte
for size and rest is unused.

There's new misc bit for mmap2 to signal there's build
id data in it:

  #define PERF_RECORD_MISC_MMAP_BUILD_ID   (1 << 14)

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-4-jolsa@kernel.org
2021-01-14 19:29:58 -08:00
Jiri Olsa 921f88fc89 bpf: Add size arg to build_id_parse function
It's possible to have other build id types (other than default SHA1).
Currently there's also ld support for MD5 build id.

Adding size argument to build_id_parse function, that returns (if defined)
size of the parsed build id, so we can recognize the build id type.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-3-jolsa@kernel.org
2021-01-14 19:29:58 -08:00