locking/refcounts: Change WARN() to WARN_ONCE()
Linus noticed that the new refcount.h APIs used WARN(), which would turn
into a dmesg DoS if it triggers frequently on some buggy driver.
So make sure we only warn once. These warnings are never supposed to happen,
so it's typically not a problem to lose subsequent warnings.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CA+55aFzbYUTZ=oqZ2YgDjY0C2_n6ODhTfqj6V+m5xWmDxsuB0w@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/lib/refcount.c b/lib/refcount.c
index 1d33366..aa09ad3 100644
--- a/lib/refcount.c
+++ b/lib/refcount.c
@@ -58,7 +58,7 @@
val = old;
}
- WARN(new == UINT_MAX, "refcount_t: saturated; leaking memory.\n");
+ WARN_ONCE(new == UINT_MAX, "refcount_t: saturated; leaking memory.\n");
return true;
}
@@ -66,7 +66,7 @@
void refcount_add(unsigned int i, refcount_t *r)
{
- WARN(!refcount_add_not_zero(i, r), "refcount_t: addition on 0; use-after-free.\n");
+ WARN_ONCE(!refcount_add_not_zero(i, r), "refcount_t: addition on 0; use-after-free.\n");
}
EXPORT_SYMBOL_GPL(refcount_add);
@@ -97,7 +97,7 @@
val = old;
}
- WARN(new == UINT_MAX, "refcount_t: saturated; leaking memory.\n");
+ WARN_ONCE(new == UINT_MAX, "refcount_t: saturated; leaking memory.\n");
return true;
}
@@ -111,7 +111,7 @@
*/
void refcount_inc(refcount_t *r)
{
- WARN(!refcount_inc_not_zero(r), "refcount_t: increment on 0; use-after-free.\n");
+ WARN_ONCE(!refcount_inc_not_zero(r), "refcount_t: increment on 0; use-after-free.\n");
}
EXPORT_SYMBOL_GPL(refcount_inc);
@@ -125,7 +125,7 @@
new = val - i;
if (new > val) {
- WARN(new > val, "refcount_t: underflow; use-after-free.\n");
+ WARN_ONCE(new > val, "refcount_t: underflow; use-after-free.\n");
return false;
}
@@ -164,7 +164,7 @@
void refcount_dec(refcount_t *r)
{
- WARN(refcount_dec_and_test(r), "refcount_t: decrement hit 0; leaking memory.\n");
+ WARN_ONCE(refcount_dec_and_test(r), "refcount_t: decrement hit 0; leaking memory.\n");
}
EXPORT_SYMBOL_GPL(refcount_dec);
@@ -204,7 +204,7 @@
new = val - 1;
if (new > val) {
- WARN(new > val, "refcount_t: underflow; use-after-free.\n");
+ WARN_ONCE(new > val, "refcount_t: underflow; use-after-free.\n");
return true;
}