[PATCH v17 42/47] dept: call dept_hardirqs_off() in local_irq_*() regardless of irq state

Byungchul Park
2025-10-02T08:14:07Z

For dept to function properly, dept_task()->hardirqs_enabled must be set
correctly. If it fails to set this value to false, for example, dept
may mistakenly think irq is still enabled even when it's not.

Do dept_hardirqs_off() regardless of irq state not to miss any
unexpected cases by any chance e.g. changes of the state by asm code.

Signed-off-by: Byungchul Park <byungchul@sk.com>
---
include/linux/irqflags.h | 14 ++++++++++++++
kernel/dependency/dept.c | 1 +
2 files changed, 15 insertions(+)

diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
index d8b9cf093f83..586f5bad4da7 100644
--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -214,6 +214,13 @@ extern void warn_bogus_irq_restore(void);
raw_local_irq_disable(); \
if (!was_disabled) \
trace_hardirqs_off(); \
+ /* \
+ * Just in case that C code has missed \
+ * trace_hardirqs_off() at the first \
+ * place e.g. disabling irq at asm code.\
+ */ \
+ else \
+ dept_hardirqs_off(); \
} while (0)

#define local_irq_save(flags) \
@@ -221,6 +228,13 @@ extern void warn_bogus_irq_restore(void);
raw_local_irq_save(flags); \
if (!raw_irqs_disabled_flags(flags)) \
trace_hardirqs_off(); \
+ /* \
+ * Just in case that C code has missed \
+ * trace_hardirqs_off() at the first \
+ * place e.g. disabling irq at asm code.\
+ */ \
+ else \
+ dept_hardirqs_off(); \
} while (0)

#define local_irq_restore(flags) \
diff --git a/kernel/dependency/dept.c b/kernel/dependency/dept.c
index 0f4464657288..a17b185d6a6a 100644
--- a/kernel/dependency/dept.c
+++ b/kernel/dependency/dept.c
@@ -2248,6 +2248,7 @@ void noinstr dept_hardirqs_off(void)
*/
dept_task()->hardirqs_enabled = false;
}
+EXPORT_SYMBOL_GPL(dept_hardirqs_off);

void noinstr dept_update_cxt(void)
{
--
2.17.1