Linux kernel source tree
Go to file
Waiman Long 150e298ae0 cgroup/cpuset: Fix a partition error with CPU hotplug
It was found during testing that an invalid leaf partition with an
empty effective exclusive CPU list can become a valid empty partition
with no CPU afer an offline/online operation of an unrelated CPU. An
empty partition root is allowed in the special case that it has no
task in its cgroup and has distributed out all its CPUs to its child
partitions. That is certainly not the case here.

The problem is in the cpumask_subsets() test in the hotplug case
(update with no new mask) of update_parent_effective_cpumask() as it
also returns true if the effective exclusive CPU list is empty. Fix that
by addding the cpumask_empty() test to root out this exception case.
Also add the cpumask_empty() test in cpuset_hotplug_update_tasks()
to avoid calling update_parent_effective_cpumask() for this special case.

Fixes: 0c7f293efc ("cgroup/cpuset: Add cpuset.cpus.exclusive.effective for v2")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2025-08-09 08:42:28 -10:00
arch gpio updates for v6.17-rc1 2025-08-09 08:15:43 +03:00
block block-6.17-20250808 2025-08-09 08:47:28 +03:00
certs
crypto Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
Documentation EFI updates for v6.17 2025-08-09 18:10:01 +03:00
drivers EFI updates for v6.17 2025-08-09 18:10:01 +03:00
fs NFS client updates for Linux 6.17 2025-08-09 07:20:44 +03:00
include TTY revert fix for 6.16-rc1 2025-08-09 18:12:23 +03:00
init Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
io_uring io_uring/memmap: cast nr_pages to size_t before shifting 2025-08-08 06:35:14 -06:00
ipc vfs-6.17-rc1.mmap_prepare 2025-07-28 13:43:25 -07:00
kernel cgroup/cpuset: Fix a partition error with CPU hotplug 2025-08-09 08:42:28 -10:00
lib block-6.17-20250808 2025-08-09 08:47:28 +03:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm Significant patch series in this pull request: 2025-08-05 16:02:07 +03:00
net NFS client updates for Linux 6.17 2025-08-09 07:20:44 +03:00
rust Rust changes for v6.17 2025-08-03 13:49:10 -07:00
samples Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
scripts Kbuild updates for v6.17 2025-08-06 07:32:52 +03:00
security + Features 2025-08-04 08:17:28 -07:00
sound gpio updates for v6.17-rc1 2025-08-09 08:15:43 +03:00
tools bpf-fixes 2025-08-09 09:03:21 +03:00
usr usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12 15:03:17 +09:00
virt Merge tag 'kvm-x86-no_assignment-6.17' of https://github.com/kvm-x86/linux into HEAD 2025-07-29 08:36:42 -04:00
.clang-format Linux 6.15-rc5 2025-05-06 16:39:25 +10:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig
.get_maintainer.ignore
.gitattributes
.gitignore gitignore: allow .pylintrc to be tracked 2025-07-02 17:10:04 -06:00
.mailmap Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
.pylintrc docs: add a .pylintrc file with sys path for docs scripts 2025-04-09 12:10:33 -06:00
.rustfmt.toml
COPYING
CREDITS Kbuild updates for v6.17 2025-08-06 07:32:52 +03:00
Kbuild
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS spi: Fixes for v6.17 2025-08-09 08:43:24 +03:00
Makefile Kbuild updates for v6.17 2025-08-06 07:32:52 +03:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.