diff options
| author |   jsg <jsg@openbsd.org> | 2020-06-21 16:41:56 +0000 |
|---|---|---|
| committer | jsg <jsg@openbsd.org> | 2020-06-21 16:41:56 +0000 |
| commit | edef9da4822c7e22f40a459b5c59fe7c165437f9 (patch) | |
| tree | 9f5defcd36c8f27a1c284eb0dee0359e772b163d /sys/dev/pci/drm/include/linux/mutex.h | |
| parent | Set up exec_map and phys_map. (diff) | |
| download | wireguard-openbsd-edef9da4822c7e22f40a459b5c59fe7c165437f9.tar.xz wireguard-openbsd-edef9da4822c7e22f40a459b5c59fe7c165437f9.zip | |
correct mutex_lock_interruptible()
Linux kernel code often passes errors around as negative numbers cast to
pointers. As rw_enter() returns a errno on failure
mutex_lock_interruptible() negated the return value. But this did not
account for ERESTART being -1 which would return 1 to the caller.
sthen@ periodically hit a uvm_fault() in i915_request_create() which
was caused by attempting to use 1 as a pointer.
ok kettenis@
Diffstat (limited to 'sys/dev/pci/drm/include/linux/mutex.h')
| -rw-r--r-- | sys/dev/pci/drm/include/linux/mutex.h | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/sys/dev/pci/drm/include/linux/mutex.h b/sys/dev/pci/drm/include/linux/mutex.h index 5910b9743c0..f396289c62b 100644 --- a/sys/dev/pci/drm/include/linux/mutex.h +++ b/sys/dev/pci/drm/include/linux/mutex.h @@ -10,9 +10,8 @@ #define DEFINE_MUTEX(x) struct rwlock x -#define mutex_lock_interruptible(rwl) -rw_enter(rwl, RW_WRITE | RW_INTR) #define mutex_lock_interruptible_nested(rwl, subc) \ - -rw_enter(rwl, RW_WRITE | RW_INTR) + mutex_lock_interruptible(rwl) #define mutex_lock(rwl) rw_enter_write(rwl) #define mutex_lock_nest_lock(rwl, sub) rw_enter_write(rwl) #define mutex_lock_nested(rwl, sub) rw_enter_write(rwl) @@ -21,6 +20,14 @@ #define mutex_is_locked(rwl) (rw_status(rwl) != 0) #define mutex_destroy(rwl) +static inline int +mutex_lock_interruptible(struct rwlock *rwl) +{ + if (rw_enter(rwl, RW_WRITE | RW_INTR) != 0) + return -EINTR; + return 0; +} + enum mutex_trylock_recursive_result { MUTEX_TRYLOCK_FAILED, MUTEX_TRYLOCK_SUCCESS, |