[PATCH 6.18 065/314] sched_ext: Fix SCX_EFLAG_INITIALIZED being a no-op flag

Sasha Levin
2026-03-10T11:25:41Z

From: David Carlier <devnexen@gmail.com>

[ Upstream commit 749989b2d90ddc7dd253ad3b11a77cf882721acf ]

SCX_EFLAG_INITIALIZED is the sole member of enum scx_exit_flags with no
explicit value, so the compiler assigns it 0. This makes the bitwise OR
in scx_ops_init() a no-op:

sch->exit_info->flags |= SCX_EFLAG_INITIALIZED; /* |= 0 */

As a result, BPF schedulers cannot distinguish whether ops.init()
completed successfully by inspecting exit_info->flags.

Assign the value 1LLU << 0 so the flag is actually set.

Fixes: f3aec2adce8d ("sched_ext: Add SCX_EFLAG_INITIALIZED to indicate successful ops.init()")
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/sched/ext_internal.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/ext_internal.h b/kernel/sched/ext_internal.h
index 601cfae8cc765..8039a750490f8 100644
--- a/kernel/sched/ext_internal.h
+++ b/kernel/sched/ext_internal.h
@@ -69,7 +69,7 @@ enum scx_exit_flags {
* info communication. The following flag indicates whether ops.init()
* finished successfully.
*/
- SCX_EFLAG_INITIALIZED,
+ SCX_EFLAG_INITIALIZED = 1LLU << 0,
};

/*
--
2.51.0