44263 Commits

Author SHA1 Message Date
Linus Torvalds
1a1e09890c workqueue: BH workqueue conversions for v6.9
This pull request contains two patches that convert tasklet users to BH
 workqueue - backtractest and usb hcd. DM conversions are being routed
 through the respective subsystem tree. Hopefully, the next cycle will see a
 lot more conversions.
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Merge tag 'wq-for-6.9-bh-conversions' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue BH conversions from Tejun Heo:
 "This contains two patches that convert tasklet users to BH workqueues:
  backtracetest and usb hcd.

  DM conversions are being routed through the respective subsystem tree.
  Hopefully, the next cycle will see a lot more conversions"

* tag 'wq-for-6.9-bh-conversions' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  usb: core: hcd: Convert from tasklet to BH workqueue
  backtracetest: Convert from tasklet to BH workqueue
2024-03-11 13:05:19 -07:00
Linus Torvalds
ff887eb07c workqueue: Changes for v6.9
This cycle, a lot of workqueue changes including some that are significant
 and invasive.
 
 - During v6.6 cycle, unbound workqueues were updated so that they are more
   topology aware and flexible, which among other things improved workqueue
   behavior on modern multi-L3 CPUs. In the process, 636b927eba5b
   ("workqueue: Make unbound workqueues to use per-cpu pool_workqueues")
   switched unbound workqueues to use per-CPU frontend pool_workqueues as a
   part of increasing front-back mapping flexibility.
 
   An unwelcome side effect of this change was that this made max concurrency
   enforcement per-CPU blowing up the maximum number of allowed concurrent
   executions. I incorrectly assumed that this wouldn't cause practical
   problems as most unbound workqueue users are self-regulate max
   concurrency; however, there definitely are which don't (e.g. on IO paths)
   and the drastic increase in the allowed max concurrency led to noticeable
   perf regressions in some use cases.
 
   This is now addressed by separating out max concurrency enforcement to a
   separate struct - wq_node_nr_active - which makes @max_active consistently
   mean system-wide max concurrency regardless of the number of CPUs or
   (finally) NUMA nodes. This is a rather invasive and, in places, a bit
   clunky; however, the clunkiness rises from the the inherent requirement to
   handle the disagreement between the execution locality domain and max
   concurrency enforcement domain on some modern machines. See 5797b1c18919
   ("workqueue: Implement system-wide nr_active enforcement for unbound
   workqueues") for more details.
 
 - BH workqueue support is added. They are similar to per-CPU workqueues but
   execute work items in the softirq context. This is expected to replace
   tasklet. However, currently, it's missing the ability to disable and
   enable work items which is needed to convert many tasklet users. To avoid
   crowding this merge window too much, this will be included in the next
   merge window. A separate pull request will be sent for the couple
   conversion patches that are currently pending.
 
 - Waiman plugged a long-standing hole in workqueue CPU isolation where
   ordered workqueues didn't follow wq_unbound_cpumask updates. Ordered
   workqueues now follow the same rules as other unbound workqueues.
 
 - More CPU isolation improvements: Juri fixed another deficit in workqueue
   isolation where unbound rescuers don't respect wq_unbound_cpumask.
   Leonardo fixed delayed_work timers firing on isolated CPUs.
 
 - Other misc changes.
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Merge tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:
 "This cycle, a lot of workqueue changes including some that are
  significant and invasive.

   - During v6.6 cycle, unbound workqueues were updated so that they are
     more topology aware and flexible, which among other things improved
     workqueue behavior on modern multi-L3 CPUs. In the process, commit
     636b927eba5b ("workqueue: Make unbound workqueues to use per-cpu
     pool_workqueues") switched unbound workqueues to use per-CPU
     frontend pool_workqueues as a part of increasing front-back mapping
     flexibility.

     An unwelcome side effect of this change was that this made max
     concurrency enforcement per-CPU blowing up the maximum number of
     allowed concurrent executions. I incorrectly assumed that this
     wouldn't cause practical problems as most unbound workqueue users
     are self-regulate max concurrency; however, there definitely are
     which don't (e.g. on IO paths) and the drastic increase in the
     allowed max concurrency led to noticeable perf regressions in some
     use cases.

     This is now addressed by separating out max concurrency enforcement
     to a separate struct - wq_node_nr_active - which makes @max_active
     consistently mean system-wide max concurrency regardless of the
     number of CPUs or (finally) NUMA nodes. This is a rather invasive
     and, in places, a bit clunky; however, the clunkiness rises from
     the the inherent requirement to handle the disagreement between the
     execution locality domain and max concurrency enforcement domain on
     some modern machines.

     See commit 5797b1c18919 ("workqueue: Implement system-wide
     nr_active enforcement for unbound workqueues") for more details.

   - BH workqueue support is added.

     They are similar to per-CPU workqueues but execute work items in
     the softirq context. This is expected to replace tasklet. However,
     currently, it's missing the ability to disable and enable work
     items which is needed to convert many tasklet users. To avoid
     crowding this merge window too much, this will be included in the
     next merge window. A separate pull request will be sent for the
     couple conversion patches that are currently pending.

   - Waiman plugged a long-standing hole in workqueue CPU isolation
     where ordered workqueues didn't follow wq_unbound_cpumask updates.
     Ordered workqueues now follow the same rules as other unbound
     workqueues.

   - More CPU isolation improvements: Juri fixed another deficit in
     workqueue isolation where unbound rescuers don't respect
     wq_unbound_cpumask. Leonardo fixed delayed_work timers firing on
     isolated CPUs.

   - Other misc changes"

* tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (54 commits)
  workqueue: Drain BH work items on hot-unplugged CPUs
  workqueue: Introduce from_work() helper for cleaner callback declarations
  workqueue: Control intensive warning threshold through cmdline
  workqueue: Make @flags handling consistent across set_work_data() and friends
  workqueue: Remove clear_work_data()
  workqueue: Factor out work_grab_pending() from __cancel_work_sync()
  workqueue: Clean up enum work_bits and related constants
  workqueue: Introduce work_cancel_flags
  workqueue: Use variable name irq_flags for saving local irq flags
  workqueue: Reorganize flush and cancel[_sync] functions
  workqueue: Rename __cancel_work_timer() to __cancel_timer_sync()
  workqueue: Use rcu_read_lock_any_held() instead of rcu_read_lock_held()
  workqueue: Cosmetic changes
  workqueue, irq_work: Build fix for !CONFIG_IRQ_WORK
  workqueue: Fix queue_work_on() with BH workqueues
  async: Use a dedicated unbound workqueue with raised min_active
  workqueue: Implement workqueue_set_min_active()
  workqueue: Fix kernel-doc comment of unplug_oldest_pwq()
  workqueue: Bind unbound workqueue rescuer to wq_unbound_cpumask
  kernel/workqueue: Let rescuers follow unbound wq cpumask changes
  ...
2024-03-11 12:50:42 -07:00
Linus Torvalds
e5a3878c94 RCU pull request for v6.9
This pull request contains the following branches:
 
 rcu-doc.2024.02.14a: Documentation updates.
 
 rcu-nocb.2024.02.14a: RCU NOCB updates, code cleanups, unnecessary
         barrier removals and minor bug fixes.
 
 rcu-exp.2024.02.14a: RCU exp, fixing a circular dependency between
         workqueue and RCU expedited callback handling.
 
 rcu-tasks.2024.02.26a: RCU tasks, avoiding deadlocks in do_exit() when
         calling synchronize_rcu_task() with a mutex hold, maintaining
 	real-time response in rcu_tasks_postscan() and a minor
         fix for tasks trace quiescence check.
 
 rcu-misc.2024.02.14a: Misc updates, comments and readibility
 	improvement, boot time parameter for lazy RCU and rcutorture
 	improvement.
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Merge tag 'rcu.next.v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/boqun/linux

Pull RCU updates from Boqun Feng:

 - Eliminate deadlocks involving do_exit() and RCU tasks, by Paul:
   Instead of SRCU read side critical sections, now a percpu list is
   used in do_exit() for scaning yet-to-exit tasks

 - Fix a deadlock due to the dependency between workqueue and RCU
   expedited grace period, reported by Anna-Maria Behnsen and Thomas
   Gleixner and fixed by Frederic: Now RCU expedited always uses its own
   kthread worker instead of a workqueue

 - RCU NOCB updates, code cleanups, unnecessary barrier removals and
   minor bug fixes

 - Maintain real-time response in rcu_tasks_postscan() and a minor fix
   for tasks trace quiescence check

 - Misc updates, comments and readibility improvement, boot time
   parameter for lazy RCU and rcutorture improvement

 - Documentation updates

* tag 'rcu.next.v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/boqun/linux: (34 commits)
  rcu-tasks: Maintain real-time response in rcu_tasks_postscan()
  rcu-tasks: Eliminate deadlocks involving do_exit() and RCU tasks
  rcu-tasks: Maintain lists to eliminate RCU-tasks/do_exit() deadlocks
  rcu-tasks: Initialize data to eliminate RCU-tasks/do_exit() deadlocks
  rcu-tasks: Initialize callback lists at rcu_init() time
  rcu-tasks: Add data to eliminate RCU-tasks/do_exit() deadlocks
  rcu-tasks: Repair RCU Tasks Trace quiescence check
  rcu/sync: remove un-used rcu_sync_enter_start function
  rcutorture: Suppress rtort_pipe_count warnings until after stalls
  srcu: Improve comments about acceleration leak
  rcu: Provide a boot time parameter to control lazy RCU
  rcu: Rename jiffies_till_flush to jiffies_lazy_flush
  doc: Update checklist.rst discussion of callback execution
  doc: Clarify use of slab constructors and SLAB_TYPESAFE_BY_RCU
  context_tracking: Fix kerneldoc headers for __ct_user_{enter,exit}()
  doc: Add EARLY flag to early-parsed kernel boot parameters
  doc: Add CONFIG_RCU_STRICT_GRACE_PERIOD to checklist.rst
  doc: Make checklist.rst note that spinlocks are implied RCU readers
  doc: Make whatisRCU.rst note that spinlocks are RCU readers
  doc: Spinlocks are implied RCU readers
  ...
2024-03-11 12:02:50 -07:00
Linus Torvalds
1ddeeb2a05 for-6.9/block-20240310
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Merge tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - MD pull requests via Song:
      - Cleanup redundant checks (Yu Kuai)
      - Remove deprecated headers (Marc Zyngier, Song Liu)
      - Concurrency fixes (Li Lingfeng)
      - Memory leak fix (Li Nan)
      - Refactor raid1 read_balance (Yu Kuai, Paul Luse)
      - Clean up and fix for md_ioctl (Li Nan)
      - Other small fixes (Gui-Dong Han, Heming Zhao)
      - MD atomic limits (Christoph)

 - NVMe pull request via Keith:
      - RDMA target enhancements (Max)
      - Fabrics fixes (Max, Guixin, Hannes)
      - Atomic queue_limits usage (Christoph)
      - Const use for class_register (Ricardo)
      - Identification error handling fixes (Shin'ichiro, Keith)

 - Improvement and cleanup for cached request handling (Christoph)

 - Moving towards atomic queue limits. Core changes and driver bits so
   far (Christoph)

 - Fix UAF issues in aoeblk (Chun-Yi)

 - Zoned fix and cleanups (Damien)

 - s390 dasd cleanups and fixes (Jan, Miroslav)

 - Block issue timestamp caching (me)

 - noio scope guarding for zoned IO (Johannes)

 - block/nvme PI improvements (Kanchan)

 - Ability to terminate long running discard loop (Keith)

 - bdev revalidation fix (Li)

 - Get rid of old nr_queues hack for kdump kernels (Ming)

 - Support for async deletion of ublk (Ming)

 - Improve IRQ bio recycling (Pavel)

 - Factor in CPU capacity for remote vs local completion (Qais)

 - Add shared_tags configfs entry for null_blk (Shin'ichiro

 - Fix for a regression in page refcounts introduced by the folio
   unification (Tony)

 - Misc fixes and cleanups (Arnd, Colin, John, Kunwu, Li, Navid,
   Ricardo, Roman, Tang, Uwe)

* tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux: (221 commits)
  block: partitions: only define function mac_fix_string for CONFIG_PPC_PMAC
  block/swim: Convert to platform remove callback returning void
  cdrom: gdrom: Convert to platform remove callback returning void
  block: remove disk_stack_limits
  md: remove mddev->queue
  md: don't initialize queue limits
  md/raid10: use the atomic queue limit update APIs
  md/raid5: use the atomic queue limit update APIs
  md/raid1: use the atomic queue limit update APIs
  md/raid0: use the atomic queue limit update APIs
  md: add queue limit helpers
  md: add a mddev_is_dm helper
  md: add a mddev_add_trace_msg helper
  md: add a mddev_trace_remap helper
  bcache: move calculation of stripe_size and io_opt into bcache_device_init
  virtio_blk: Do not use disk_set_max_open/active_zones()
  aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts
  block: move capacity validation to blkpg_do_ioctl()
  block: prevent division by zero in blk_rq_stat_sum()
  drbd: atomically update queue limits in drbd_reconsider_queue_parameters
  ...
2024-03-11 11:43:44 -07:00
Linus Torvalds
910202f00a vfs-6.9.super
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Merge tag 'vfs-6.9.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull block handle updates from Christian Brauner:
 "Last cycle we changed opening of block devices, and opening a block
  device would return a bdev_handle. This allowed us to implement
  support for restricting and forbidding writes to mounted block
  devices. It was accompanied by converting and adding helpers to
  operate on bdev_handles instead of plain block devices.

  That was already a good step forward but ultimately it isn't necessary
  to have special purpose helpers for opening block devices internally
  that return a bdev_handle.

  Fundamentally, opening a block device internally should just be
  equivalent to opening files. So now all internal opens of block
  devices return files just as a userspace open would. Instead of
  introducing a separate indirection into bdev_open_by_*() via struct
  bdev_handle bdev_file_open_by_*() is made to just return a struct
  file. Opening and closing a block device just becomes equivalent to
  opening and closing a file.

  This all works well because internally we already have a pseudo fs for
  block devices and so opening block devices is simple. There's a few
  places where we needed to be careful such as during boot when the
  kernel is supposed to mount the rootfs directly without init doing it.
  Here we need to take care to ensure that we flush out any asynchronous
  file close. That's what we already do for opening, unpacking, and
  closing the initramfs. So nothing new here.

  The equivalence of opening and closing block devices to regular files
  is a win in and of itself. But it also has various other advantages.
  We can remove struct bdev_handle completely. Various low-level helpers
  are now private to the block layer. Other helpers were simply
  removable completely.

  A follow-up series that is already reviewed build on this and makes it
  possible to remove bdev->bd_inode and allows various clean ups of the
  buffer head code as well. All places where we stashed a bdev_handle
  now just stash a file and use simple accessors to get to the actual
  block device which was already the case for bdev_handle"

* tag 'vfs-6.9.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits)
  block: remove bdev_handle completely
  block: don't rely on BLK_OPEN_RESTRICT_WRITES when yielding write access
  bdev: remove bdev pointer from struct bdev_handle
  bdev: make struct bdev_handle private to the block layer
  bdev: make bdev_{release, open_by_dev}() private to block layer
  bdev: remove bdev_open_by_path()
  reiserfs: port block device access to file
  ocfs2: port block device access to file
  nfs: port block device access to files
  jfs: port block device access to file
  f2fs: port block device access to files
  ext4: port block device access to file
  erofs: port device access to file
  btrfs: port device access to file
  bcachefs: port block device access to file
  target: port block device access to file
  s390: port block device access to file
  nvme: port block device access to file
  block2mtd: port device access to files
  bcache: port block device access to files
  ...
2024-03-11 10:52:34 -07:00
Linus Torvalds
b5683a37c8 vfs-6.9.pidfd
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Merge tag 'vfs-6.9.pidfd' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull pdfd updates from Christian Brauner:

 - Until now pidfds could only be created for thread-group leaders but
   not for threads. There was no technical reason for this. We simply
   had no users that needed support for this. Now we do have users that
   need support for this.

   This introduces a new PIDFD_THREAD flag for pidfd_open(). If that
   flag is set pidfd_open() creates a pidfd that refers to a specific
   thread.

   In addition, we now allow clone() and clone3() to be called with
   CLONE_PIDFD | CLONE_THREAD which wasn't possible before.

   A pidfd that refers to an individual thread differs from a pidfd that
   refers to a thread-group leader:

    (1) Pidfds are pollable. A task may poll a pidfd and get notified
        when the task has exited.

        For thread-group leader pidfds the polling task is woken if the
        thread-group is empty. In other words, if the thread-group
        leader task exits when there are still threads alive in its
        thread-group the polling task will not be woken when the
        thread-group leader exits but rather when the last thread in the
        thread-group exits.

        For thread-specific pidfds the polling task is woken if the
        thread exits.

    (2) Passing a thread-group leader pidfd to pidfd_send_signal() will
        generate thread-group directed signals like kill(2) does.

        Passing a thread-specific pidfd to pidfd_send_signal() will
        generate thread-specific signals like tgkill(2) does.

        The default scope of the signal is thus determined by the type
        of the pidfd.

        Since use-cases exist where the default scope of the provided
        pidfd needs to be overriden the following flags are added to
        pidfd_send_signal():

         - PIDFD_SIGNAL_THREAD
           Send a thread-specific signal.

         - PIDFD_SIGNAL_THREAD_GROUP
           Send a thread-group directed signal.

         - PIDFD_SIGNAL_PROCESS_GROUP
           Send a process-group directed signal.

        The scope change will only work if the struct pid is actually
        used for this scope.

        For example, in order to send a thread-group directed signal the
        provided pidfd must be used as a thread-group leader and
        similarly for PIDFD_SIGNAL_PROCESS_GROUP the struct pid must be
        used as a process group leader.

 - Move pidfds from the anonymous inode infrastructure to a tiny pseudo
   filesystem. This will unblock further work that we weren't able to do
   simply because of the very justified limitations of anonymous inodes.
   Moving pidfds to a tiny pseudo filesystem allows for statx on pidfds
   to become useful for the first time. They can now be compared by
   inode number which are unique for the system lifetime.

   Instead of stashing struct pid in file->private_data we can now stash
   it in inode->i_private. This makes it possible to introduce concepts
   that operate on a process once all file descriptors have been closed.
   A concrete example is kill-on-last-close. Another side-effect is that
   file->private_data is now freed up for per-file options for pidfds.

   Now, each struct pid will refer to a different inode but the same
   struct pid will refer to the same inode if it's opened multiple
   times. In contrast to now where each struct pid refers to the same
   inode.

   The tiny pseudo filesystem is not visible anywhere in userspace
   exactly like e.g., pipefs and sockfs. There's no lookup, there's no
   complex inode operations, nothing. Dentries and inodes are always
   deleted when the last pidfd is closed.

   We allocate a new inode and dentry for each struct pid and we reuse
   that inode and dentry for all pidfds that refer to the same struct
   pid. The code is entirely optional and fairly small. If it's not
   selected we fallback to anonymous inodes. Heavily inspired by nsfs.

   The dentry and inode allocation mechanism is moved into generic
   infrastructure that is now shared between nsfs and pidfs. The
   path_from_stashed() helper must be provided with a stashing location,
   an inode number, a mount, and the private data that is supposed to be
   used and it will provide a path that can be passed to dentry_open().

   The helper will try retrieve an existing dentry from the provided
   stashing location. If a valid dentry is found it is reused. If not a
   new one is allocated and we try to stash it in the provided location.
   If this fails we retry until we either find an existing dentry or the
   newly allocated dentry could be stashed. Subsequent openers of the
   same namespace or task are then able to reuse it.

 - Currently it is only possible to get notified when a task has exited,
   i.e., become a zombie and userspace gets notified with EPOLLIN. We
   now also support waiting until the task has been reaped, notifying
   userspace with EPOLLHUP.

 - Ensure that ESRCH is reported for getfd if a task is exiting instead
   of the confusing EBADF.

 - Various smaller cleanups to pidfd functions.

* tag 'vfs-6.9.pidfd' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (23 commits)
  libfs: improve path_from_stashed()
  libfs: add stashed_dentry_prune()
  libfs: improve path_from_stashed() helper
  pidfs: convert to path_from_stashed() helper
  nsfs: convert to path_from_stashed() helper
  libfs: add path_from_stashed()
  pidfd: add pidfs
  pidfd: move struct pidfd_fops
  pidfd: allow to override signal scope in pidfd_send_signal()
  pidfd: change pidfd_send_signal() to respect PIDFD_THREAD
  signal: fill in si_code in prepare_kill_siginfo()
  selftests: add ESRCH tests for pidfd_getfd()
  pidfd: getfd should always report ESRCH if a task is exiting
  pidfd: clone: allow CLONE_THREAD | CLONE_PIDFD together
  pidfd: exit: kill the no longer used thread_group_exited()
  pidfd: change do_notify_pidfd() to use __wake_up(poll_to_key(EPOLLIN))
  pid: kill the obsolete PIDTYPE_PID code in transfer_pid()
  pidfd: kill the no longer needed do_notify_pidfd() in de_thread()
  pidfd_poll: report POLLHUP when pid_task() == NULL
  pidfd: implement PIDFD_THREAD flag for pidfd_open()
  ...
2024-03-11 10:21:06 -07:00
Linus Torvalds
97ec9715a8 linux_kselftest-kunit-6.9-rc1
This KUnit next update for Linux 6.9-rc1 consists of:
 
 -- fix to make kunit_bus_type const
 
 -- kunit tool change to Print UML command
 
 -- DRM device creation helpers are now using the new kunit device
    creation helpers. This change resulted in DRM helpers switching
    from using a platform_device, to a dedicated bus and device type
    used by kunit. kunit devices don't set DMA mask and this caused
    regression on some drm tests as they can't allocate DMA buffers.
    Fix this problem by setting DMA masks on the kunit device during
    initialization.
 
 -- KUnit has several macros which accept a log message, which can
    contain printf format specifiers. Some of these (the explicit
    log macros) already use the __printf() gcc attribute to ensure
    the format specifiers are valid, but those which could fail the
    test, and hence used __kunit_do_failed_assertion() behind the scenes,
    did not.
 
    These include: KUNIT_EXPECT_*_MSG(), KUNIT_ASSERT_*_MSG(), and
    KUNIT_FAIL()
 
    A 9 patch series adds the __printf() attribute, and fixes all of
    the issues uncovered.
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Merge tag 'linux_kselftest-kunit-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull KUnit updates from Shuah Khan:

 - fix to make kunit_bus_type const

 - kunit tool change to Print UML command

 - DRM device creation helpers are now using the new kunit device
   creation helpers. This change resulted in DRM helpers switching from
   using a platform_device, to a dedicated bus and device type used by
   kunit. kunit devices don't set DMA mask and this caused regression on
   some drm tests as they can't allocate DMA buffers. Fix this problem
   by setting DMA masks on the kunit device during initialization.

 - KUnit has several macros which accept a log message, which can
   contain printf format specifiers. Some of these (the explicit log
   macros) already use the __printf() gcc attribute to ensure the format
   specifiers are valid, but those which could fail the test, and hence
   used __kunit_do_failed_assertion() behind the scenes, did not.

   These include: KUNIT_EXPECT_*_MSG(), KUNIT_ASSERT_*_MSG(), and
   KUNIT_FAIL()

   A nine-patch series adds the __printf() attribute, and fixes all of
   the issues uncovered.

* tag 'linux_kselftest-kunit-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: Annotate _MSG assertion variants with gnu printf specifiers
  drm: tests: Fix invalid printf format specifiers in KUnit tests
  drm/xe/tests: Fix printf format specifiers in xe_migrate test
  net: test: Fix printf format specifier in skb_segment kunit test
  rtc: test: Fix invalid format specifier.
  time: test: Fix incorrect format specifier
  lib: memcpy_kunit: Fix an invalid format specifier in an assertion msg
  lib/cmdline: Fix an invalid format specifier in an assertion msg
  kunit: test: Log the correct filter string in executor_test
  kunit: Setup DMA masks on the kunit device
  kunit: make kunit_bus_type const
  kunit: Mark filter* params as rw
  kunit: tool: Print UML command
2024-03-11 09:32:28 -07:00
Rafael J. Wysocki
3bd834640b Merge branch 'pm-em'
Merge Enery Model changes for 6.9-rc1:

 - Allow the Energy Model to be updated dynamically (Lukasz Luba).

* pm-em: (24 commits)
  PM: EM: Fix nr_states warnings in static checks
  Documentation: EM: Update with runtime modification design
  PM: EM: Add em_dev_compute_costs()
  PM: EM: Remove old table
  PM: EM: Change debugfs configuration to use runtime EM table data
  drivers/thermal/devfreq_cooling: Use new Energy Model interface
  drivers/thermal/cpufreq_cooling: Use new Energy Model interface
  powercap/dtpm_devfreq: Use new Energy Model interface to get table
  powercap/dtpm_cpu: Use new Energy Model interface to get table
  PM: EM: Optimize em_cpu_energy() and remove division
  PM: EM: Support late CPUs booting and capacity adjustment
  PM: EM: Add performance field to struct em_perf_state and optimize
  PM: EM: Add em_perf_state_from_pd() to get performance states table
  PM: EM: Introduce em_dev_update_perf_domain() for EM updates
  PM: EM: Add functions for memory allocations for new EM tables
  PM: EM: Use runtime modified EM for CPUs energy estimation in EAS
  PM: EM: Introduce runtime modifiable table
  PM: EM: Split the allocation and initialization of the EM table
  PM: EM: Check if the get_cost() callback is present in em_compute_costs()
  PM: EM: Introduce em_compute_costs()
  ...
2024-03-11 15:59:51 +01:00
Rafael J. Wysocki
86b84bdd5c Merge branch 'pm-sleep'
Merge changes related to system-wide power management for 6.9-rc1:

 - Fix and clean up system suspend statistics collection (Rafael
   Wysocki).

 - Simplify device suspend and resume handling in the power management
   core code (Rafael Wysocki).

 - Add support for LZ4 compression algorithm to the hibernation image
   creation and loading code (Nikhil V).

 - Fix PCI hibernation support description (Yiwei Lin).

 - Make hibernation take set_memory_ro() return values into account as
   appropriate (Christophe Leroy).

 - Set mem_sleep_current during kernel command line setup to avoid an
   ordering issue with handling it (Maulik Shah).

 - Fix wake IRQs handling when pm_runtime_force_suspend() is used as a
   driver's system suspend callback (Qingliang Li).

* pm-sleep: (21 commits)
  PM: sleep: wakeirq: fix wake irq warning in system suspend
  PM: suspend: Set mem_sleep_current during kernel command line setup
  PM: hibernate: Don't ignore return from set_memory_ro()
  PM: hibernate: Support to select compression algorithm
  Documentation: PM: Fix PCI hibernation support description
  PM: hibernate: Add support for LZ4 compression for hibernation
  PM: hibernate: Move to crypto APIs for LZO compression
  PM: hibernate: Rename lzo* to make it generic
  PM: sleep: Call dpm_async_fn() directly in each suspend phase
  PM: sleep: Move devices to new lists earlier in each suspend phase
  PM: sleep: Move some assignments from under a lock
  PM: sleep: stats: Log errors right after running suspend callbacks
  PM: sleep: stats: Use locking in dpm_save_failed_dev()
  PM: sleep: stats: Call dpm_save_failed_step() at most once per phase
  PM: sleep: stats: Define suspend_stats next to the code using it
  PM: sleep: stats: Use unsigned int for success and failure counters
  PM: sleep: stats: Use an array of step failure counters
  PM: sleep: stats: Use array of suspend step names
  PM: sleep: Relocate two device PM core functions
  PM: sleep: Simplify dpm_suspended_list walk in dpm_resume()
  ...
2024-03-11 15:10:57 +01:00
Linus Torvalds
fa4b851b4a Tracing fixes for v6.8-rc7:
- Do not allow large strings (> 4096) as single write to trace_marker
 
   The size of a string written into trace_marker was determined by
   the size of the sub-buffer in the ring buffer. That size is
   dependent on the PAGE_SIZE of the architecture as it can be mapped
   into user space. But on PowerPC, where PAGE_SIZE is 64K, that made
   the limit of the string of writing into trace_marker 64K.
 
   One of the selftests looks at the size of the ring buffer sub-buffers
   and writes that plus more into the trace_marker. The write will take
   what it can and report back what it consumed so that the user space
   application (like echo) will write the rest of the string. The string
   is stored in the ring buffer and can be read via the "trace" or
   "trace_pipe" files.
 
   The reading of the ring buffer uses vsnprintf(), which uses a precision
   "%.*s" to make sure it only reads what is stored in the buffer, as
   a bug could cause the string to be non terminated.
 
   With the combination of the precision change and the PAGE_SIZE of 64K
   allowing huge strings to be added into the ring buffer, plus the test
   that would actually stress that limit, a bug was reported that
   the precision used was too big for "%.*s" as the string was close to
   64K in size and the max precision of vsnprintf is 32K.
 
   Linus suggested not to have that precision as it could hide a bug
   if the string was again stored without a nul byte.
 
   Another issue that was brought up is that the trace_seq buffer is
   also based on PAGE_SIZE even though it is not tied to the architecture
   limit like the ring buffer sub-buffer is. Having it be 64K * 2 is
   simply just too big and wasting memory on systems with 64K page sizes.
   It is now hardcoded to 8K which is what all other architectures with
   4K PAGE_SIZE has.
 
   Finally, the write to trace_marker is now limited to 4K as there is no
   reason to write larger strings into trace_marker.
 
 - ring_buffer_wait() should not loop.
   The ring_buffer_wait() does not have the full context (yet) on if it
   should loop or not. Just exit the loop as soon as its woken up and
   let the callers decide to loop or not (they already do, so it's a bit
   redundant).
 
 - Fix shortest_full field to be the smallest amount in the ring buffer that
   a waiter is waiting for. The "shortest_full" field is updated when a new
   waiter comes in and wants to wait for a smaller amount of data in the
   ring buffer than other waiters. But after all waiters are woken up, it's
   not reset, so if another waiter comes in wanting to wait for more data,
   it will be woken up when the ring buffer has a smaller amount from what
   the previous waiters were waiting for.
 
 - The wake up all waiters on close is incorrectly called frome .release()
   and not from .flush() so it will never wake up any waiters as the
   .release() will not get called until all .read() calls are finished. And the
   wakeup is for the waiters in those .read() calls.
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Merge tag 'trace-ring-buffer-v6.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Do not allow large strings (> 4096) as single write to trace_marker

   The size of a string written into trace_marker was determined by the
   size of the sub-buffer in the ring buffer. That size is dependent on
   the PAGE_SIZE of the architecture as it can be mapped into user
   space. But on PowerPC, where PAGE_SIZE is 64K, that made the limit of
   the string of writing into trace_marker 64K.

   One of the selftests looks at the size of the ring buffer sub-buffers
   and writes that plus more into the trace_marker. The write will take
   what it can and report back what it consumed so that the user space
   application (like echo) will write the rest of the string. The string
   is stored in the ring buffer and can be read via the "trace" or
   "trace_pipe" files.

   The reading of the ring buffer uses vsnprintf(), which uses a
   precision "%.*s" to make sure it only reads what is stored in the
   buffer, as a bug could cause the string to be non terminated.

   With the combination of the precision change and the PAGE_SIZE of 64K
   allowing huge strings to be added into the ring buffer, plus the test
   that would actually stress that limit, a bug was reported that the
   precision used was too big for "%.*s" as the string was close to 64K
   in size and the max precision of vsnprintf is 32K.

   Linus suggested not to have that precision as it could hide a bug if
   the string was again stored without a nul byte.

   Another issue that was brought up is that the trace_seq buffer is
   also based on PAGE_SIZE even though it is not tied to the
   architecture limit like the ring buffer sub-buffer is. Having it be
   64K * 2 is simply just too big and wasting memory on systems with 64K
   page sizes. It is now hardcoded to 8K which is what all other
   architectures with 4K PAGE_SIZE has.

   Finally, the write to trace_marker is now limited to 4K as there is
   no reason to write larger strings into trace_marker.

 - ring_buffer_wait() should not loop.

   The ring_buffer_wait() does not have the full context (yet) on if it
   should loop or not. Just exit the loop as soon as its woken up and
   let the callers decide to loop or not (they already do, so it's a bit
   redundant).

 - Fix shortest_full field to be the smallest amount in the ring buffer
   that a waiter is waiting for. The "shortest_full" field is updated
   when a new waiter comes in and wants to wait for a smaller amount of
   data in the ring buffer than other waiters. But after all waiters are
   woken up, it's not reset, so if another waiter comes in wanting to
   wait for more data, it will be woken up when the ring buffer has a
   smaller amount from what the previous waiters were waiting for.

 - The wake up all waiters on close is incorrectly called frome
   .release() and not from .flush() so it will never wake up any waiters
   as the .release() will not get called until all .read() calls are
   finished. And the wakeup is for the waiters in those .read() calls.

* tag 'trace-ring-buffer-v6.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Use .flush() call to wake up readers
  ring-buffer: Fix resetting of shortest_full
  ring-buffer: Fix waking up ring buffer readers
  tracing: Limit trace_marker writes to just 4K
  tracing: Limit trace_seq size to just 8K and not depend on architecture PAGE_SIZE
  tracing: Remove precision vsnprintf() check from print event
2024-03-10 11:53:21 -07:00
Steven Rostedt (Google)
e5d7c19165 tracing: Use .flush() call to wake up readers
The .release() function does not get called until all readers of a file
descriptor are finished.

If a thread is blocked on reading a file descriptor in ring_buffer_wait(),
and another thread closes the file descriptor, it will not wake up the
other thread as ring_buffer_wake_waiters() is called by .release(), and
that will not get called until the .read() is finished.

The issue originally showed up in trace-cmd, but the readers are actually
other processes with their own file descriptors. So calling close() would wake
up the other tasks because they are blocked on another descriptor then the
one that was closed(). But there's other wake ups that solve that issue.

When a thread is blocked on a read, it can still hang even when another
thread closed its descriptor.

This is what the .flush() callback is for. Have the .flush() wake up the
readers.

Link: https://lore.kernel.org/linux-trace-kernel/20240308202432.107909457@goodmis.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linke li <lilinke99@qq.com>
Cc: Rabin Vincent <rabin@rab.in>
Fixes: f3ddb74ad0790 ("tracing: Wake up ring buffer waiters on closing of the file")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-10 12:27:47 -04:00
Steven Rostedt (Google)
68282dd930 ring-buffer: Fix resetting of shortest_full
The "shortest_full" variable is used to keep track of the waiter that is
waiting for the smallest amount on the ring buffer before being woken up.
When a tasks waits on the ring buffer, it passes in a "full" value that is
a percentage. 0 means wake up on any data. 1-100 means wake up from 1% to
100% full buffer.

As all waiters are on the same wait queue, the wake up happens for the
waiter with the smallest percentage.

The problem is that the smallest_full on the cpu_buffer that stores the
smallest amount doesn't get reset when all the waiters are woken up. It
does get reset when the ring buffer is reset (echo > /sys/kernel/tracing/trace).

This means that tasks may be woken up more often then when they want to
be. Instead, have the shortest_full field get reset just before waking up
all the tasks. If the tasks wait again, they will update the shortest_full
before sleeping.

Also add locking around setting of shortest_full in the poll logic, and
change "work" to "rbwork" to match the variable name for rb_irq_work
structures that are used in other places.

Link: https://lore.kernel.org/linux-trace-kernel/20240308202431.948914369@goodmis.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linke li <lilinke99@qq.com>
Cc: Rabin Vincent <rabin@rab.in>
Fixes: 2c2b0a78b3739 ("ring-buffer: Add percentage of ring buffer full to wake up reader")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-10 12:27:40 -04:00
Steven Rostedt (Google)
b359457368 ring-buffer: Fix waking up ring buffer readers
A task can wait on a ring buffer for when it fills up to a specific
watermark. The writer will check the minimum watermark that waiters are
waiting for and if the ring buffer is past that, it will wake up all the
waiters.

The waiters are in a wait loop, and will first check if a signal is
pending and then check if the ring buffer is at the desired level where it
should break out of the loop.

If a file that uses a ring buffer closes, and there's threads waiting on
the ring buffer, it needs to wake up those threads. To do this, a
"wait_index" was used.

Before entering the wait loop, the waiter will read the wait_index. On
wakeup, it will check if the wait_index is different than when it entered
the loop, and will exit the loop if it is. The waker will only need to
update the wait_index before waking up the waiters.

This had a couple of bugs. One trivial one and one broken by design.

The trivial bug was that the waiter checked the wait_index after the
schedule() call. It had to be checked between the prepare_to_wait() and
the schedule() which it was not.

The main bug is that the first check to set the default wait_index will
always be outside the prepare_to_wait() and the schedule(). That's because
the ring_buffer_wait() doesn't have enough context to know if it should
break out of the loop.

The loop itself is not needed, because all the callers to the
ring_buffer_wait() also has their own loop, as the callers have a better
sense of what the context is to decide whether to break out of the loop
or not.

Just have the ring_buffer_wait() block once, and if it gets woken up, exit
the function and let the callers decide what to do next.

Link: https://lore.kernel.org/all/CAHk-=whs5MdtNjzFkTyaUy=vHi=qwWgPi0JgTe6OYUYMNSRZfg@mail.gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240308202431.792933613@goodmis.org

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linke li <lilinke99@qq.com>
Cc: Rabin Vincent <rabin@rab.in>
Fixes: e30f53aad2202 ("tracing: Do not busy wait in buffer splice")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-10 12:24:59 -04:00
Ricardo B. Marliere
6b6ca09611 rtc: class: make rtc_class constant
Since commit 43a7206b0963 ("driver core: class: make class_register() take
a const *"), the driver core allows for struct class to be in read-only
memory, so move the rtc_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Link: https://lore.kernel.org/r/20240305-class_cleanup-abelloni-v1-1-944c026137c8@marliere.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2024-03-08 12:05:10 +01:00
Eric Dumazet
aa70d2d16f net: move skbuff_cache(s) to net_hotdata
skbuff_cache, skbuff_fclone_cache and skb_small_head_cache
are used in rx/tx fast paths.

Move them to net_hotdata for better cache locality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240306160031.874438-11-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-07 21:12:42 -08:00
Toke Høiland-Jørgensen
7a4b21250b bpf: Fix stackmap overflow check on 32-bit arches
The stackmap code relies on roundup_pow_of_two() to compute the number
of hash buckets, and contains an overflow check by checking if the
resulting value is 0. However, on 32-bit arches, the roundup code itself
can overflow by doing a 32-bit left-shift of an unsigned long value,
which is undefined behaviour, so it is not guaranteed to truncate
neatly. This was triggered by syzbot on the DEVMAP_HASH type, which
contains the same check, copied from the hashtab code.

The commit in the fixes tag actually attempted to fix this, but the fix
did not account for the UB, so the fix only works on CPUs where an
overflow does result in a neat truncation to zero, which is not
guaranteed. Checking the value before rounding does not have this
problem.

Fixes: 6183f4d3a0a2 ("bpf: Check for integer overflow when using roundup_pow_of_two()")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Bui Quang Minh <minhquangbui99@gmail.com>
Message-ID: <20240307120340.99577-4-toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-07 20:06:25 -08:00
Toke Høiland-Jørgensen
6787d916c2 bpf: Fix hashtab overflow check on 32-bit arches
The hashtab code relies on roundup_pow_of_two() to compute the number of
hash buckets, and contains an overflow check by checking if the
resulting value is 0. However, on 32-bit arches, the roundup code itself
can overflow by doing a 32-bit left-shift of an unsigned long value,
which is undefined behaviour, so it is not guaranteed to truncate
neatly. This was triggered by syzbot on the DEVMAP_HASH type, which
contains the same check, copied from the hashtab code. So apply the same
fix to hashtab, by moving the overflow check to before the roundup.

Fixes: daaf427c6ab3 ("bpf: fix arraymap NULL deref and missing overflow and zero size checks")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Message-ID: <20240307120340.99577-3-toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-07 20:05:56 -08:00
Toke Høiland-Jørgensen
281d464a34 bpf: Fix DEVMAP_HASH overflow check on 32-bit arches
The devmap code allocates a number hash buckets equal to the next power
of two of the max_entries value provided when creating the map. When
rounding up to the next power of two, the 32-bit variable storing the
number of buckets can overflow, and the code checks for overflow by
checking if the truncated 32-bit value is equal to 0. However, on 32-bit
arches the rounding up itself can overflow mid-way through, because it
ends up doing a left-shift of 32 bits on an unsigned long value. If the
size of an unsigned long is four bytes, this is undefined behaviour, so
there is no guarantee that we'll end up with a nice and tidy 0-value at
the end.

Syzbot managed to turn this into a crash on arm32 by creating a
DEVMAP_HASH with max_entries > 0x80000000 and then trying to update it.
Fix this by moving the overflow check to before the rounding up
operation.

Fixes: 6f9d451ab1a3 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Link: https://lore.kernel.org/r/000000000000ed666a0611af6818@google.com
Reported-and-tested-by: syzbot+8cd36f6b65f3cafd400a@syzkaller.appspotmail.com
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Message-ID: <20240307120340.99577-2-toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-07 20:02:38 -08:00
Alexei Starovoitov
fe5064158c bpf: Tell bpf programs kernel's PAGE_SIZE
vmlinux BTF includes all kernel enums.
Add __PAGE_SIZE = PAGE_SIZE enum, so that bpf programs
that include vmlinux.h can easily access it.

Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240307031228.42896-7-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-07 14:58:48 -08:00
Alexei Starovoitov
cf2c2e4a3d bpf: Plumb get_unmapped_area() callback into bpf_map_ops
Subsequent patches introduce bpf_arena that imposes special alignment
requirements on address selection.

Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240307031228.42896-4-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-07 14:58:48 -08:00
Alexei Starovoitov
8d94f1357c bpf: Recognize '__map' suffix in kfunc arguments
Recognize 'void *p__map' kfunc argument as 'struct bpf_map *p__map'.
It allows kfunc to have 'void *' argument for maps, since bpf progs
will call them as:
struct {
        __uint(type, BPF_MAP_TYPE_ARENA);
	...
} arena SEC(".maps");

bpf_kfunc_with_map(... &arena ...);

Underneath libbpf will load CONST_PTR_TO_MAP into the register via ld_imm64
insn. If kfunc was defined with 'struct bpf_map *' it would pass the
verifier as well, but bpf prog would need to type cast the argument
(void *)&arena, which is not clean.

Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240307031228.42896-3-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-07 14:58:48 -08:00
Alexei Starovoitov
88d1d4a7ee bpf: Allow kfuncs return 'void *'
Recognize return of 'void *' from kfunc as returning unknown scalar.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240307031228.42896-2-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-07 14:58:48 -08:00
Jakub Kicinski
e3afe5dd3a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts.

Adjacent changes:

net/core/page_pool_user.c
  0b11b1c5c320 ("netdev: let netlink core handle -EMSGSIZE errors")
  429679dcf7d9 ("page_pool: fix netlink dump stop/resume")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-07 10:29:36 -08:00
Linus Torvalds
df4793505a Including fixes from bpf, ipsec and netfilter.
No solution yet for the stmmac issue mentioned in the last PR,
 but it proved to be a lockdep false positive, not a blocker.
 
 Current release - regressions:
 
   - dpll: move all dpll<>netdev helpers to dpll code, fix build
     regression with old compilers
 
 Current release - new code bugs:
 
   - page_pool: fix netlink dump stop/resume
 
 Previous releases - regressions:
 
   - bpf: fix verifier to check bpf_func_state->callback_depth when pruning
        states as otherwise unsafe programs could get accepted
 
   - ipv6: avoid possible UAF in ip6_route_mpath_notify()
 
   - ice: reconfig host after changing MSI-X on VF
 
   - mlx5:
     - e-switch, change flow rule destination checking
     - add a memory barrier to prevent a possible null-ptr-deref
     - switch to using _bh variant of of spinlock where needed
 
 Previous releases - always broken:
 
   - netfilter: nf_conntrack_h323: add protection for bmp length out of range
 
   - bpf: fix to zero-initialise xdp_rxq_info struct before running XDP
 	program in CPU map which led to random xdp_md fields
 
   - xfrm: fix UDP encapsulation in TX packet offload
 
   - netrom: fix data-races around sysctls
 
   - ice:
     - fix potential NULL pointer dereference in ice_bridge_setlink()
     - fix uninitialized dplls mutex usage
 
   - igc: avoid returning frame twice in XDP_REDIRECT
 
   - i40e: disable NAPI right after disabling irqs when handling xsk_pool
 
   - geneve: make sure to pull inner header in geneve_rx()
 
   - sparx5: fix use after free inside sparx5_del_mact_entry
 
   - dsa: microchip: fix register write order in ksz8_ind_write8()
 
 Misc:
 
   -  selftests: mptcp: fixes for diag.sh
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-6.8-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

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

  No solution yet for the stmmac issue mentioned in the last PR, but it
  proved to be a lockdep false positive, not a blocker.

  Current release - regressions:

   - dpll: move all dpll<>netdev helpers to dpll code, fix build
     regression with old compilers

  Current release - new code bugs:

   - page_pool: fix netlink dump stop/resume

  Previous releases - regressions:

   - bpf: fix verifier to check bpf_func_state->callback_depth when
     pruning states as otherwise unsafe programs could get accepted

   - ipv6: avoid possible UAF in ip6_route_mpath_notify()

   - ice: reconfig host after changing MSI-X on VF

   - mlx5:
       - e-switch, change flow rule destination checking
       - add a memory barrier to prevent a possible null-ptr-deref
       - switch to using _bh variant of of spinlock where needed

  Previous releases - always broken:

   - netfilter: nf_conntrack_h323: add protection for bmp length out of
     range

   - bpf: fix to zero-initialise xdp_rxq_info struct before running XDP
     program in CPU map which led to random xdp_md fields

   - xfrm: fix UDP encapsulation in TX packet offload

   - netrom: fix data-races around sysctls

   - ice:
       - fix potential NULL pointer dereference in ice_bridge_setlink()
       - fix uninitialized dplls mutex usage

   - igc: avoid returning frame twice in XDP_REDIRECT

   - i40e: disable NAPI right after disabling irqs when handling
     xsk_pool

   - geneve: make sure to pull inner header in geneve_rx()

   - sparx5: fix use after free inside sparx5_del_mact_entry

   - dsa: microchip: fix register write order in ksz8_ind_write8()

  Misc:

   - selftests: mptcp: fixes for diag.sh"

* tag 'net-6.8-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (63 commits)
  net: pds_core: Fix possible double free in error handling path
  netrom: Fix data-races around sysctl_net_busy_read
  netrom: Fix a data-race around sysctl_netrom_link_fails_count
  netrom: Fix a data-race around sysctl_netrom_routing_control
  netrom: Fix a data-race around sysctl_netrom_transport_no_activity_timeout
  netrom: Fix a data-race around sysctl_netrom_transport_requested_window_size
  netrom: Fix a data-race around sysctl_netrom_transport_busy_delay
  netrom: Fix a data-race around sysctl_netrom_transport_acknowledge_delay
  netrom: Fix a data-race around sysctl_netrom_transport_maximum_tries
  netrom: Fix a data-race around sysctl_netrom_transport_timeout
  netrom: Fix data-races around sysctl_netrom_network_ttl_initialiser
  netrom: Fix a data-race around sysctl_netrom_obsolescence_count_initialiser
  netrom: Fix a data-race around sysctl_netrom_default_path_quality
  netfilter: nf_conntrack_h323: Add protection for bmp length out of range
  netfilter: nf_tables: mark set as dead when unbinding anonymous set with timeout
  netfilter: nft_ct: fix l3num expectations with inet pseudo family
  netfilter: nf_tables: reject constant set with timeout
  netfilter: nf_tables: disallow anonymous set with timeout flag
  net/rds: fix WARNING in rds_conn_connect_if_down
  net: dsa: microchip: fix register write order in ksz8_ind_write8()
  ...
2024-03-07 09:23:33 -08:00
Eduard Zingerman
bd70a8fb7c bpf: Allow all printable characters in BTF DATASEC names
The intent is to allow libbpf to use SEC("?.struct_ops") to identify
struct_ops maps that are optional, e.g. like in the following BPF code:

    SEC("?.struct_ops")
    struct test_ops optional_map = { ... };

Which yields the following BTF:

    ...
    [13] DATASEC '?.struct_ops' size=0 vlen=...
    ...

To load such BTF libbpf rewrites DATASEC name before load.
After this patch the rewrite won't be necessary.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-15-eddyz87@gmail.com
2024-03-06 15:18:16 -08:00
Alexei Starovoitov
4f81c16f50 bpf: Recognize that two registers are safe when their ranges match
When open code iterators, bpf_loop or may_goto are used the following two
states are equivalent and safe to prune the search:

cur state: fp-8_w=scalar(id=3,smin=umin=smin32=umin32=2,smax=umax=smax32=umax32=11,var_off=(0x0; 0xf))
old state: fp-8_rw=scalar(id=2,smin=umin=smin32=umin32=1,smax=umax=smax32=umax32=11,var_off=(0x0; 0xf))

In other words "exact" state match should ignore liveness and precision
marks, since open coded iterator logic didn't complete their propagation,
reg_old->type == NOT_INIT && reg_cur->type != NOT_INIT is also not safe to
prune while looping, but range_within logic that applies to scalars,
ptr_to_mem, map_value, pkt_ptr is safe to rely on.

Avoid doing such comparison when regular infinite loop detection logic is
used, otherwise bounded loop logic will declare such "infinite loop" as
false positive. Such example is in progs/verifier_loops1.c
not_an_inifinite_loop().

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Tested-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240306031929.42666-3-alexei.starovoitov@gmail.com
2024-03-06 15:18:00 -08:00
Alexei Starovoitov
011832b97b bpf: Introduce may_goto instruction
Introduce may_goto instruction that from the verifier pov is similar to
open coded iterators bpf_for()/bpf_repeat() and bpf_loop() helper, but it
doesn't iterate any objects.
In assembly 'may_goto' is a nop most of the time until bpf runtime has to
terminate the program for whatever reason. In the current implementation
may_goto has a hidden counter, but other mechanisms can be used.
For programs written in C the later patch introduces 'cond_break' macro
that combines 'may_goto' with 'break' statement and has similar semantics:
cond_break is a nop until bpf runtime has to break out of this loop.
It can be used in any normal "for" or "while" loop, like

  for (i = zero; i < cnt; cond_break, i++) {

The verifier recognizes that may_goto is used in the program, reserves
additional 8 bytes of stack, initializes them in subprog prologue, and
replaces may_goto instruction with:
aux_reg = *(u64 *)(fp - 40)
if aux_reg == 0 goto pc+off
aux_reg -= 1
*(u64 *)(fp - 40) = aux_reg

may_goto instruction can be used by LLVM to implement __builtin_memcpy,
__builtin_strcmp.

may_goto is not a full substitute for bpf_for() macro.
bpf_for() doesn't have induction variable that verifiers sees,
so 'i' in bpf_for(i, 0, 100) is seen as imprecise and bounded.

But when the code is written as:
for (i = 0; i < 100; cond_break, i++)
the verifier see 'i' as precise constant zero,
hence cond_break (aka may_goto) doesn't help to converge the loop.
A static or global variable can be used as a workaround:
static int zero = 0;
for (i = zero; i < 100; cond_break, i++) // works!

may_goto works well with arena pointers that don't need to be bounds
checked on access. Load/store from arena returns imprecise unbounded
scalar and loops with may_goto pass the verifier.

Reserve new opcode BPF_JMP | BPF_JCOND for may_goto insn.
JCOND stands for conditional pseudo jump.
Since goto_or_nop insn was proposed, it may use the same opcode.
may_goto vs goto_or_nop can be distinguished by src_reg:
code = BPF_JMP | BPF_JCOND
src_reg = 0 - may_goto
src_reg = 1 - goto_or_nop

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Tested-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240306031929.42666-2-alexei.starovoitov@gmail.com
2024-03-06 15:17:31 -08:00
yang.zhang
4bb7be96fc kexec: copy only happens before uchunk goes to zero
When loading segments, ubytes is <= mbytes.  When ubytes is exhausted,
there could be remaining mbytes.  Then in the while loop, the buf pointer
advancing with mchunk will causing meaningless reading even though it
doesn't harm.

So let's change to make sure that all of the copying and the rest only
happens before uchunk goes to zero.

Link: https://lkml.kernel.org/r/20240222092119.5602-1-gaoshanliukou@163.com
Signed-off-by: yang.zhang <yang.zhang@hexintek.com>
Acked-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06 13:07:39 -08:00
Oleg Nesterov
a436184e3b get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
This initialization is incomplete and unnecessary, neither do_group_exit()
nor PF_USER_WORKER need ksig->info.

Link: https://lkml.kernel.org/r/20240226165653.GA20834@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Wen Yang <wenyang.linux@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06 13:07:39 -08:00
Oleg Nesterov
dd69edd643 get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
ksig->ka and ksig->info are not initialized if get_signal() returns 0 or
if the caller is PF_USER_WORKER.

Check signr != 0 before SA_EXPOSE_TAGBITS and move the "out" label down.

The latter means that ksig->sig won't be initialized if a PF_USER_WORKER
thread gets a fatal signal but this is fine, PF_USER_WORKER's don't use
ksig. And there is nothing new, in this case ksig->ka and ksig-info are
not initialized anyway. Add a comment.

Link: https://lkml.kernel.org/r/20240226165650.GA20829@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Wen Yang <wenyang.linux@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06 13:07:39 -08:00
Oleg Nesterov
49fd5f5ac4 get_signal: don't abuse ksig->info.si_signo and ksig->sig
Patch series "get_signal: minor cleanups and fix".

Lets remove this clear_siginfo() right now.  It is incomplete (and thus
looks confusing) and unnecessary.  Also, PF_USER_WORKER's already don't
get a fully initialized ksig anyway.


This patch (of 3):

Cleanup and preparation for the next changes.

get_signal() uses signr or ksig->info.si_signo or ksig->sig in a chaotic
way, this looks confusing. Change it to always use signr.

Link: https://lkml.kernel.org/r/20240226165612.GA20787@redhat.com
Link: https://lkml.kernel.org/r/20240226165647.GA20826@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Wen Yang <wenyang.linux@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06 13:07:39 -08:00
Gang Li Subject: padata: dispatch works on
eb52286634 Author: Gang Li padata: dispatch works on
different nodes Date: Thu, 22 Feb 2024 22:04:17 +0800

When a group of tasks that access different nodes are scheduled on the
same node, they may encounter bandwidth bottlenecks and access latency.

Thus, numa_aware flag is introduced here, allowing tasks to be distributed
across different nodes to fully utilize the advantage of multi-node
systems.

Link: https://lkml.kernel.org/r/20240222140422.393911-5-gang.li@linux.dev
Signed-off-by: Gang Li <ligang.bdlg@bytedance.com>
Tested-by: David Rientjes <rientjes@google.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06 13:04:17 -08:00
Steven Rostedt (Google)
095fe48912 tracing: Limit trace_marker writes to just 4K
Limit the max print event of trace_marker to just 4K string size. This must
also be less than the amount that can be held by a trace_seq along with
the text that is before the output (like the task name, PID, CPU, state,
etc). As trace_seq is made to handle large events (some greater than 4K).
Make the max size of a trace_marker write event be 4K which is guaranteed
to fit in the trace_seq buffer.

Link: https://lore.kernel.org/linux-trace-kernel/20240304223433.4ba47dff@gandalf.local.home

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-06 13:27:26 -05:00
Steven Rostedt (Google)
5efd3e2aef tracing: Remove precision vsnprintf() check from print event
This reverts 60be76eeabb3d ("tracing: Add size check when printing
trace_marker output"). The only reason the precision check was added
was because of a bug that miscalculated the write size of the string into
the ring buffer and it truncated it removing the terminating nul byte. On
reading the trace it crashed the kernel. But this was due to the bug in
the code that happened during development and should never happen in
practice. If anything, the precision can hide bugs where the string in the
ring buffer isn't nul terminated and it will not be checked.

Link: https://lore.kernel.org/all/C7E7AF1A-D30F-4D18-B8E5-AF1EF58004F5@linux.ibm.com/
Link: https://lore.kernel.org/linux-trace-kernel/20240227125706.04279ac2@gandalf.local.home
Link: https://lore.kernel.org/all/20240302111244.3a1674be@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20240304174341.2a561d9f@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: 60be76eeabb3d ("tracing: Add size check when printing trace_marker output")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-06 13:26:26 -05:00
Masami Hiramatsu (Google)
25f00e40ce tracing/probes: Support $argN in return probe (kprobe and fprobe)
Support accessing $argN in the return probe events. This will help users to
record entry data in function return (exit) event for simplfing the function
entry/exit information in one event, and record the result values (e.g.
allocated object/initialized object) at function exit.

For example, if we have a function `int init_foo(struct foo *obj, int param)`
sometimes we want to check how `obj` is initialized. In such case, we can
define a new return event like below;

 # echo 'r init_foo retval=$retval param=$arg2 field1=+0($arg1)' >> kprobe_events

Thus it records the function parameter `param` and its result `obj->field1`
(the dereference will be done in the function exit timing) value at once.

This also support fprobe, BTF args and'$arg*'. So if CONFIG_DEBUG_INFO_BTF
is enabled, we can trace both function parameters and the return value
by following command.

 # echo 'f target_function%return $arg* $retval' >> dynamic_events

Link: https://lore.kernel.org/all/170952365552.229804.224112990211602895.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07 00:27:34 +09:00
Masami Hiramatsu (Google)
c18f9eabee tracing: Remove redundant #else block for BTF args from README
Remove redundant #else block for BTF args from README message.
This is a cleanup, so no change on the message.

Link: https://lore.kernel.org/all/170952364558.229804.17285528811097152410.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-07 00:27:25 +09:00
Masami Hiramatsu (Google)
035ba76014 tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init
Instead of incrementing the trace_probe::nr_args, init it at
trace_probe_init(). Without this change, there is no way to get the number
of trace_probe arguments while parsing it.
This is a cleanup, so the behavior is not changed.

Link: https://lore.kernel.org/all/170952363585.229804.13060759900346411951.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07 00:27:15 +09:00
Masami Hiramatsu (Google)
032330abd0 tracing/probes: Cleanup probe argument parser
Cleanup traceprobe_parse_probe_arg_body() to split out the
type parser and post-processing part of fetch_insn.
This makes no functional change.

Link: https://lore.kernel.org/all/170952362603.229804.9942703761682605372.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-07 00:27:06 +09:00
Masami Hiramatsu (Google)
7e37b6bc3c tracing/fprobe-event: cleanup: Fix a wrong comment in fprobe event
Despite the fprobe event,  "Kretprobe" was commented. So fix it.

Link: https://lore.kernel.org/all/170952361630.229804.10832200172327797860.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-07 00:26:57 +09:00
Frederic Weisbecker
8ca1836769 timer/migration: Fix quick check reporting late expiry
When a CPU is the last active in the hierarchy and it tries to enter
into idle, the quick check looking up the next event towards cpuidle
heuristics may report a too late expiry, such as in the following
scenario:

                        [GRP1:0]
                     migrator = NONE
                     active   = NONE
                     nextevt  = T0:0, T0:1
                     /              \
          [GRP0:0]                  [GRP0:1]
       migrator = NONE           migrator = NONE
       active   = NONE           active   = NONE
       nextevt  = T0, T1         nextevt  = T2
       /         \                /         \
      0           1              2           3
    idle       idle           idle         idle

0) The whole system is idle, and CPU 0 was the last migrator. CPU 0 has
a timer (T0), CPU 1 has a timer (T1) and CPU 2 has a timer (T2). The
expire order is T0 < T1 < T2.

                        [GRP1:0]
                     migrator = GRP0:0
                     active   = GRP0:0
                     nextevt  = T0:0(i), T0:1
                   /              \
          [GRP0:0]                  [GRP0:1]
       migrator = CPU0           migrator = NONE
       active   = CPU0           active   = NONE
       nextevt  = T0(i), T1      nextevt  = T2
       /         \                /         \
      0           1              2           3
    active       idle           idle         idle

1) CPU 0 becomes active. The (i) means a now ignored timer.

                        [GRP1:0]
                     migrator = GRP0:0
                     active   = GRP0:0
                     nextevt  = T0:1
                     /              \
          [GRP0:0]                  [GRP0:1]
       migrator = CPU0           migrator = NONE
       active   = CPU0           active   = NONE
       nextevt  = T1             nextevt  = T2
       /         \                /         \
      0           1              2           3
    active       idle           idle         idle

2) CPU 0 handles remote. No timer actually expired but ignored timers
   have been cleaned out and their sibling's timers haven't been
   propagated. As a result the top level's next event is T2 and not T1.

3) CPU 0 tries to enter idle without any global timer enqueued and calls
   tmigr_quick_check(). The expiry of T2 is returned instead of the
   expiry of T1.

When the quick check returns an expiry that is too late, the cpuidle
governor may pick up a C-state that is too deep. This may be result into
undesired CPU wake up latency if the next timer is actually close enough.

Fix this with assuming that expiries aren't sorted top-down while
performing the quick check. Pick up instead the earliest encountered one
while walking up the hierarchy.

7ee988770326 ("timers: Implement the hierarchical pull model")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240305002822.18130-1-frederic@kernel.org
2024-03-06 15:02:09 +01:00
Toke Høiland-Jørgensen
2487007aa3 cpumap: Zero-initialise xdp_rxq_info struct before running XDP program
When running an XDP program that is attached to a cpumap entry, we don't
initialise the xdp_rxq_info data structure being used in the xdp_buff
that backs the XDP program invocation. Tobias noticed that this leads to
random values being returned as the xdp_md->rx_queue_index value for XDP
programs running in a cpumap.

This means we're basically returning the contents of the uninitialised
memory, which is bad. Fix this by zero-initialising the rxq data
structure before running the XDP program.

Fixes: 9216477449f3 ("bpf: cpumap: Add the possibility to attach an eBPF program to cpumap")
Reported-by: Tobias Böhm <tobias@aibor.de>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20240305213132.11955-1-toke@redhat.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-05 16:48:53 -08:00
Eduard Zingerman
e9a8e5a587 bpf: check bpf_func_state->callback_depth when pruning states
When comparing current and cached states verifier should consider
bpf_func_state->callback_depth. Current state cannot be pruned against
cached state, when current states has more iterations left compared to
cached state. Current state has more iterations left when it's
callback_depth is smaller.

Below is an example illustrating this bug, minimized from mailing list
discussion [0] (assume that BPF_F_TEST_STATE_FREQ is set).
The example is not a safe program: if loop_cb point (1) is followed by
loop_cb point (2), then division by zero is possible at point (4).

    struct ctx {
    	__u64 a;
    	__u64 b;
    	__u64 c;
    };

    static void loop_cb(int i, struct ctx *ctx)
    {
    	/* assume that generated code is "fallthrough-first":
    	 * if ... == 1 goto
    	 * if ... == 2 goto
    	 * <default>
    	 */
    	switch (bpf_get_prandom_u32()) {
    	case 1:  /* 1 */ ctx->a = 42; return 0; break;
    	case 2:  /* 2 */ ctx->b = 42; return 0; break;
    	default: /* 3 */ ctx->c = 42; return 0; break;
    	}
    }

    SEC("tc")
    __failure
    __flag(BPF_F_TEST_STATE_FREQ)
    int test(struct __sk_buff *skb)
    {
    	struct ctx ctx = { 7, 7, 7 };

    	bpf_loop(2, loop_cb, &ctx, 0);              /* 0 */
    	/* assume generated checks are in-order: .a first */
    	if (ctx.a == 42 && ctx.b == 42 && ctx.c == 7)
    		asm volatile("r0 /= 0;":::"r0");    /* 4 */
    	return 0;
    }

Prior to this commit verifier built the following checkpoint tree for
this example:

 .------------------------------------- Checkpoint / State name
 |    .-------------------------------- Code point number
 |    |   .---------------------------- Stack state {ctx.a,ctx.b,ctx.c}
 |    |   |        .------------------- Callback depth in frame #0
 v    v   v        v
   - (0) {7P,7P,7},depth=0
     - (3) {7P,7P,7},depth=1
       - (0) {7P,7P,42},depth=1
         - (3) {7P,7,42},depth=2
           - (0) {7P,7,42},depth=2      loop terminates because of depth limit
             - (4) {7P,7,42},depth=0    predicted false, ctx.a marked precise
             - (6) exit
(a)      - (2) {7P,7,42},depth=2
           - (0) {7P,42,42},depth=2     loop terminates because of depth limit
             - (4) {7P,42,42},depth=0   predicted false, ctx.a marked precise
             - (6) exit
(b)      - (1) {7P,7P,42},depth=2
           - (0) {42P,7P,42},depth=2    loop terminates because of depth limit
             - (4) {42P,7P,42},depth=0  predicted false, ctx.{a,b} marked precise
             - (6) exit
     - (2) {7P,7,7},depth=1             considered safe, pruned using checkpoint (a)
(c)  - (1) {7P,7P,7},depth=1            considered safe, pruned using checkpoint (b)

Here checkpoint (b) has callback_depth of 2, meaning that it would
never reach state {42,42,7}.
While checkpoint (c) has callback_depth of 1, and thus
could yet explore the state {42,42,7} if not pruned prematurely.
This commit makes forbids such premature pruning,
allowing verifier to explore states sub-tree starting at (c):

(c)  - (1) {7,7,7P},depth=1
       - (0) {42P,7,7P},depth=1
         ...
         - (2) {42,7,7},depth=2
           - (0) {42,42,7},depth=2      loop terminates because of depth limit
             - (4) {42,42,7},depth=0    predicted true, ctx.{a,b,c} marked precise
               - (5) division by zero

[0] https://lore.kernel.org/bpf/9b251840-7cb8-4d17-bd23-1fc8071d8eef@linux.dev/

Fixes: bb124da69c47 ("bpf: keep track of max number of bpf_loop callback iterations")
Suggested-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240222154121.6991-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-05 16:15:56 -08:00
Linus Torvalds
5847c9777c cgroup: Fixes for v6.8-rc7
Two cpuset fixes. Both are for bugs in error handling paths and low risk.
 -----BEGIN PGP SIGNATURE-----
 
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 Lm9yZwAKCRCxYfJx3gVYGaTjAQC+6pLyiH2j2XpncJ2BFID+LA5ljExmJpcRv/yb
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 =/5Ll
 -----END PGP SIGNATURE-----

Merge tag 'cgroup-for-6.8-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup fixes from Tejun Heo:
 "Two cpuset fixes. Both are for bugs in error handling paths and low
  risk"

* tag 'cgroup-for-6.8-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup/cpuset: Fix retval in update_cpumask()
  cgroup/cpuset: Fix a memory leak in update_exclusive_cpumask()
2024-03-05 14:00:22 -08:00
Peter Collingbourne
801410b26a serial: Lock console when calling into driver before registration
During the handoff from earlycon to the real console driver, we have
two separate drivers operating on the same device concurrently. In the
case of the 8250 driver these concurrent accesses cause problems due
to the driver's use of banked registers, controlled by LCR.DLAB. It is
possible for the setup(), config_port(), pm() and set_mctrl() callbacks
to set DLAB, which can cause the earlycon code that intends to access
TX to instead access DLL, leading to missed output and corruption on
the serial line due to unintended modifications to the baud rate.

In particular, for setup() we have:

univ8250_console_setup()
-> serial8250_console_setup()
-> uart_set_options()
-> serial8250_set_termios()
-> serial8250_do_set_termios()
-> serial8250_do_set_divisor()

For config_port() we have:

serial8250_config_port()
-> autoconfig()

For pm() we have:

serial8250_pm()
-> serial8250_do_pm()
-> serial8250_set_sleep()

For set_mctrl() we have (for some devices):

serial8250_set_mctrl()
-> omap8250_set_mctrl()
-> __omap8250_set_mctrl()

To avoid such problems, let's make it so that the console is locked
during pre-registration calls to these callbacks, which will prevent
the earlycon driver from running concurrently.

Remove the partial solution to this problem in the 8250 driver
that locked the console only during autoconfig_irq(), as this would
result in a deadlock with the new approach. The console continues
to be locked during autoconfig_irq() because it can only be called
through uart_configure_port().

Although this patch introduces more locking than strictly necessary
(and in particular it also locks during the call to rs485_config()
which is not affected by this issue as far as I can tell), it follows
the principle that it is the responsibility of the generic console
code to manage the earlycon handoff by ensuring that earlycon and real
console driver code cannot run concurrently, and not the individual
drivers.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://linux-review.googlesource.com/id/I7cf8124dcebf8618e6b2ee543fa5b25532de55d8
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240304214350.501253-1-pcc@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05 13:39:11 +00:00
Huang Shijie
d3246b6ee4 crash_core: export vmemmap when CONFIG_SPARSEMEM_VMEMMAP is enabled
In memory_model.h, if CONFIG_SPARSEMEM_VMEMMAP is configed, kernel will
use vmemmap to do the __pfn_to_page/page_to_pfn, and kernel will not use
the "classic sparse" to do the __pfn_to_page/page_to_pfn.

So export the vmemmap when CONFIG_SPARSEMEM_VMEMMAP is configed.  This
makes the user applications (crash, etc) get faster
pfn_to_page/page_to_pfn operations too.

Link: https://lkml.kernel.org/r/20240227014952.3184-1-shijie@os.amperecomputing.com
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Kazuhito Hagio <k-hagio-ab@nec.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-04 17:01:27 -08:00
Changbin Du
8f8cd6c0a4 modules: wait do_free_init correctly
The synchronization here is to ensure the ordering of freeing of a module
init so that it happens before W+X checking.  It is worth noting it is not
that the freeing was not happening, it is just that our sanity checkers
raced against the permission checkers which assume init memory is already
gone.

Commit 1a7b7d922081 ("modules: Use vmalloc special flag") moved calling
do_free_init() into a global workqueue instead of relying on it being
called through call_rcu(..., do_free_init), which used to allowed us call
do_free_init() asynchronously after the end of a subsequent grace period. 
The move to a global workqueue broke the gaurantees for code which needed
to be sure the do_free_init() would complete with rcu_barrier().  To fix
this callers which used to rely on rcu_barrier() must now instead use
flush_work(&init_free_wq).

Without this fix, we still could encounter false positive reports in W+X
checking since the rcu_barrier() here can not ensure the ordering now.

Even worse, the rcu_barrier() can introduce significant delay.  Eric
Chanudet reported that the rcu_barrier introduces ~0.1s delay on a
PREEMPT_RT kernel.

  [    0.291444] Freeing unused kernel memory: 5568K
  [    0.402442] Run /sbin/init as init process

With this fix, the above delay can be eliminated.

Link: https://lkml.kernel.org/r/20240227023546.2490667-1-changbin.du@huawei.com
Fixes: 1a7b7d922081 ("modules: Use vmalloc special flag")
Signed-off-by: Changbin Du <changbin.du@huawei.com>
Tested-by: Eric Chanudet <echanude@redhat.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Xiaoyi Su <suxiaoyi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-04 17:01:27 -08:00
Byungchul Park
3fb4363687 sched/numa, mm: do not try to migrate memory to memoryless nodes
Memoryless nodes do not have any memory to migrate to, so, as an
optimization, stop trying it.

Link: https://lkml.kernel.org/r/20240219041920.1183-1-byungchul@sk.com
Link: https://lkml.kernel.org/r/20240216111502.79759-1-byungchul@sk.com
Fixes: c574bbe91703 ("NUMA balancing: optimize page placement for memory tiering system")
Signed-off-by: Byungchul Park <byungchul@sk.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Benjamin Segall <bsegall@google.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-04 17:01:14 -08:00
Kui-Feng Lee
187e2af05a bpf: struct_ops supports more than one page for trampolines.
The BPF struct_ops previously only allowed one page of trampolines.
Each function pointer of a struct_ops is implemented by a struct_ops
bpf program. Each struct_ops bpf program requires a trampoline.
The following selftest patch shows each page can hold a little more
than 20 trampolines.

While one page is more than enough for the tcp-cc usecase,
the sched_ext use case shows that one page is not always enough and hits
the one page limit. This patch overcomes the one page limit by allocating
another page when needed and it is limited to a total of
MAX_IMAGE_PAGES (8) pages which is more than enough for
reasonable usages.

The variable st_map->image has been changed to st_map->image_pages, and
its type has been changed to an array of pointers to pages.

Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240224223418.526631-3-thinker.li@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-04 14:09:20 -08:00
Kui-Feng Lee
73e4f9e615 bpf, net: validate struct_ops when updating value.
Perform all validations when updating values of struct_ops maps. Doing
validation in st_ops->reg() and st_ops->update() is not necessary anymore.
However, tcp_register_congestion_control() has been called in various
places. It still needs to do validations.

Cc: netdev@vger.kernel.org
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240224223418.526631-2-thinker.li@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-03-04 10:03:57 -08:00
Eric Dumazet
80bfab79b8 net: adopt skb_network_offset() and similar helpers
This is a cleanup patch, making code a bit more concise.

1) Use skb_network_offset(skb) in place of
       (skb_network_header(skb) - skb->data)

2) Use -skb_network_offset(skb) in place of
       (skb->data - skb_network_header(skb))

3) Use skb_transport_offset(skb) in place of
       (skb_transport_header(skb) - skb->data)

4) Use skb_inner_transport_offset(skb) in place of
       (skb_inner_transport_header(skb) - skb->data)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-04 08:47:06 +00:00