Re: [PATCH v19 11/40] dept: apply sdt_might_sleep_{start,end}() to swait
flat view
From: sashiko-bot@kernel.org
Date: 2026-07-07 07:33:33
Also in:
dri-devel, linux-ide, linux-rt-devel, lkml
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The `___swait_event`, `___wait_event`, and `___wait_var_event` macros skip the `sdt_might_sleep_end()` cleanup call when returning early due to a pending signal, leading to persistent DEPT state corruption that permanently disables dependency tracking for the affected task.
--
commit 7785a2fe54ced42e856f39ece5776f11bca47be8
Author: Byungchul Park [off-list ref]
dept: apply sdt_might_sleep_{start,end}() to swait
Make dept able to track dependencies by swaits.
quoted hunk ↗ jump to hunk
diff --git a/include/linux/swait.h b/include/linux/swait.h index d324419482a0f..277ac74f61c39 100644 --- a/include/linux/swait.h +++ b/include/linux/swait.h
[ ... ]
quoted hunk ↗ jump to hunk
@@ -161,6 +162,7 @@ extern void finish_swait(struct swait_queue_head *q, struct swait_queue *wait); struct swait_queue __wait; \ long __ret = ret; \ \ + sdt_might_sleep_start(NULL); \ INIT_LIST_HEAD(&__wait.task_list); \ for (;;) { \ long __int = prepare_to_swait_event(&wq, &__wait, state);\@@ -176,6 +178,7 @@ extern void finish_swait(struct swait_queue_head *q, struct swait_queue *wait); cmd; \ } \ finish_swait(&wq, &__wait); \ + sdt_might_sleep_end(); \ __out: __ret; \ })
[Severity: High] Does this code bypass the sdt_might_sleep_end() cleanup when returning early due to a pending signal? Looking at ___swait_event(), if a task waiting interruptibly receives a signal, prepare_to_swait_event() returns a non-zero error code. The wait loop evaluates ___wait_is_interruptible(state) && __int as true and executes a goto __out; which jumps completely over this new cleanup call. If sdt_might_sleep_end() is skipped, does the task's dependency staging map remain persistently populated, effectively causing subsequent calls to dept_stage_wait() to silently exit early and disable DEPT tracking for that task? It looks like this identical sequence might also occur in the generic waitqueue macros (___wait_event in include/linux/wait.h) and the hashed waitqueue macros (___wait_var_event in include/linux/wait_bit.h). -- Sashiko AI review · https://sashiko.dev/#/patchset/20260706061928.66713-1-byungchul@sk.com?part=11