jsauer/torvalds-linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-01-11 17:10:13 +00:00
Code

cgroup: Fixes for v6.19-rc3

Browse Source 
- cpuset: Fix spurious warning when disabling remote partition after CPU
   hotplug leaves subpartitions_cpus empty. Guard the warning and invalidate
   affected partitions.
 -----BEGIN PGP SIGNATURE-----
 
 iIQEABYKACwWIQTfIjM1kS57o3GsC/uxYfJx3gVYGQUCaVHNBg4cdGpAa2VybmVs
 Lm9yZwAKCRCxYfJx3gVYGW13AQC7akGwBAjBbR5p0aoLXKl5vZ8UYiwH+7iyep2Z
 INn7ggEA/huYF4smSRk3oR8q7eiISa85mZc85EuVEAjPmBQhpAQ=
 =9UP0
 -----END PGP SIGNATURE-----

Merge tag 'cgroup-for-6.19-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup fix from Tejun Heo:

 - Fix a spurious cpuset warning when disabling remote partition after
   CPU hotplug leaves subpartitions_cpus empty. Guard the warning and
   invalidate affected partitions.

* tag 'cgroup-for-6.19-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: fix warning when disabling remote partition
This commit is contained in:
Linus Torvalds 2025-12-28 17:19:09 -08:00
commit bba0b6a1c4
1 changed files with 16 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
kernel/cgroup/cpuset.c
View File

@ -1668,7 +1668,14 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *tmp) static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *tmp)
{ {
WARN_ON_ONCE(!is_remote_partition(cs)); WARN_ON_ONCE(!is_remote_partition(cs));
WARN_ON_ONCE(!cpumask_subset(cs->effective_xcpus, subpartitions_cpus)); /*
* When a CPU is offlined, top_cpuset may end up with no available CPUs,
* which should clear subpartitions_cpus. We should not emit a warning for this
* scenario: the hierarchy is updated from top to bottom, so subpartitions_cpus
* may already be cleared when disabling the partition.
*/
WARN_ON_ONCE(!cpumask_subset(cs->effective_xcpus, subpartitions_cpus) &&
!cpumask_empty(subpartitions_cpus));
spin_lock_irq(&callback_lock); spin_lock_irq(&callback_lock);
cs->remote_partition = false; cs->remote_partition = false;
@ -3976,8 +3983,9 @@ retry:
if (remote || (is_partition_valid(cs) && is_partition_valid(parent))) if (remote || (is_partition_valid(cs) && is_partition_valid(parent)))
compute_partition_effective_cpumask(cs, &new_cpus); compute_partition_effective_cpumask(cs, &new_cpus);
if (remote && cpumask_empty(&new_cpus) && if (remote && (cpumask_empty(subpartitions_cpus) ||
partition_is_populated(cs, NULL)) { (cpumask_empty(&new_cpus) &&
partition_is_populated(cs, NULL)))) {
cs->prs_err = PERR_HOTPLUG; cs->prs_err = PERR_HOTPLUG;
remote_partition_disable(cs, tmp); remote_partition_disable(cs, tmp);
compute_effective_cpumask(&new_cpus, cs, parent); compute_effective_cpumask(&new_cpus, cs, parent);
@ -3990,9 +3998,12 @@ retry:
* 1) empty effective cpus but not valid empty partition. * 1) empty effective cpus but not valid empty partition.
* 2) parent is invalid or doesn't grant any cpus to child * 2) parent is invalid or doesn't grant any cpus to child
* partitions. * partitions.
* 3) subpartitions_cpus is empty.
*/ */
if (is_local_partition(cs) && (!is_partition_valid(parent) || if (is_local_partition(cs) &&
tasks_nocpu_error(parent, cs, &new_cpus))) (!is_partition_valid(parent) ||
tasks_nocpu_error(parent, cs, &new_cpus) ||
cpumask_empty(subpartitions_cpus)))
partcmd = partcmd_invalidate; partcmd = partcmd_invalidate;
/* /*
* On the other hand, an invalid partition root may be transitioned * On the other hand, an invalid partition root may be transitioned