fs/resctrl: Ensure default group reports tasks on monitor-only systems

2c10b3fa · Tony Luck <[email protected]> · 2026-10-09 12:39:23 -07:00

resctrl can be mounted on a system that supports monitoring but not allocation.

On such a system reading the "tasks" file in the default group reports no
tasks, even when there are tasks assigned to the default group. This problem
occurs because the check for whether a task belongs to a CTRL_MON group is
gated by a check for whether the system supports allocation.

The resctrl_arch_alloc_capable() check in is_closid_match() breaks task
reporting for the default group on monitor-only systems so remove this check.
On systems that support allocation the check is redundant.

Fixes: e6b2fac36fcc ("x86/resctrl: Use is_closid_match() in more places")
Closes: https://sashiko.dev/#/patchset/20260831174421.13921-1-tony.luck%40intel.com?part=9
Reported-by: Sashiko <[email protected]>
Signed-off-by: Tony Luck <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
Link: https://patch.msgid.link/[email protected]

Commit: 2c10b3fa5bdf61e344bc522e6c2e00d870ce7ab8
Parents: 50e5282d

Changes

1 files changed · +1 −1

File	Status	Add	Del	Content
fs/resctrl/rdtgroup.c	modified	+1	−1	View file

fs/resctrl/rdtgroup.c

View file

diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index 68be9b9..57ab090 100644
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c
@@ -685,7 +685,7 @@ static int __rdtgroup_move_task(struct task_struct *tsk,
 
 static bool is_closid_match(struct task_struct *t, struct rdtgroup *r)
 {
-	return (resctrl_arch_alloc_capable() && (r->type == RDTCTRL_GROUP) &&
+	return (r->type == RDTCTRL_GROUP &&
 		resctrl_arch_match_closid(t, r->closid));
 }
 