diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-20 12:43:05 -1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-20 12:43:05 -1000 |
| commit | 776bb6df3f16ab68c40a97dbb8af26af4185d7c0 (patch) | |
| tree | f5006a1e8d28e47201865a7979e41befa2f3e59a /include/linux | |
| parent | cb95904b470d2d347012d5e360303cf478ca5362 (diff) | |
| parent | 67e0eadd862616cb22145d6117b79b79c4ae48fe (diff) | |
Merge tag 'locking-core-2026-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- In the refcount checking code, BUG() on UAF related errors if
CONFIG_BUG_ON_DATA_CORRUPTION=y (Jann Horn)
- Add {over,under}flow detection for local_interrupt_{enable,disable}()
(Boqun Feng)
- Add kunit test case for max local_interrupt_disable() nesting level
(Boqun Feng)
- Clarify comment (Boqun Feng)
* tag 'locking-core-2026-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq: Add max local_interrupt_disable() nesting level kunit test case
irq: Explain better on NMI_MASK overflow condition
irq: Add {over,under}flow detection for local_interrupt_{enable,disable}
refcount: Use CONFIG_BUG_ON_DATA_CORRUPTION for UAF-related errors
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/hardirq.h | 2 | ||||
| -rw-r--r-- | include/linux/interrupt_rc.h | 13 |
2 files changed, 14 insertions, 1 deletions
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index 73b48dd9f135..2648c49cd8f6 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -108,7 +108,7 @@ DECLARE_PER_CPU(unsigned int, nmi_nesting); #define __preempt_count_nmi_enter() \ do { \ __preempt_count_add(HARDIRQ_OFFSET); \ - /* Maximum NMI nesting is 15. */ \ + /* NMI nesting is represented in 4 bits. */ \ BUG_ON(__this_cpu_read(nmi_nesting) >= 15); \ __this_cpu_inc(nmi_nesting); \ preempt_count_set(preempt_count() | NMI_MASK); \ diff --git a/include/linux/interrupt_rc.h b/include/linux/interrupt_rc.h index a9ed937a80e7..d385ab05a2b6 100644 --- a/include/linux/interrupt_rc.h +++ b/include/linux/interrupt_rc.h @@ -11,6 +11,7 @@ * make it easier to include without hitting circular header dependencies. */ +#include <linux/debug_locks.h> #include <linux/irqflags.h> #include <linux/preempt.h> #include <linux/processor.h> @@ -65,6 +66,13 @@ static inline void local_interrupt_disable(void) local_irq_save(flags); new_count = hardirq_disable_enter(); + /* Is hardirq disable count overflow soon? */ + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) && + DEBUG_LOCKS_WARN_ON(((new_count & HARDIRQ_DISABLE_MASK) + + (10 << HARDIRQ_DISABLE_SHIFT)) >= + HARDIRQ_DISABLE_MASK)) + return; + if ((new_count & HARDIRQ_DISABLE_MASK) == HARDIRQ_DISABLE_OFFSET) _local_interrupt_save_state(flags); } @@ -73,6 +81,11 @@ static inline void local_interrupt_enable(void) { int new_count; + /* Unpaired local_interrupt_enable()? Warn and abort. */ + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) && + DEBUG_LOCKS_WARN_ON((preempt_count() & HARDIRQ_DISABLE_MASK) == 0)) + return; + new_count = hardirq_disable_exit(); if ((new_count & HARDIRQ_DISABLE_MASK) == 0) |