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Goncalves" , Boqun Feng Cc: Peter Zijlstra , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org References: Content-Language: en-US From: Waiman Long In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 On 7/29/24 12:53, Luis Claudio R. Goncalves wrote: > On Fri, Jul 26, 2024 at 02:24:28PM -0700, Boqun Feng wrote: >> On Thu, Jul 25, 2024 at 03:45:57PM -0300, Luis Claudio R. Goncalves wrote: >>> When lockdep fails while performing the Breadth-first-search operation >>> due to lack of memory, hint that increasing the value of the configuration >>> switch LOCKDEP_CIRCULAR_QUEUE_BITS should fix the warning. >>> >>> Preface the scary bactrace with the suggestion: >>> >>> [ 163.849242] Increase LOCKDEP_CIRCULAR_QUEUE_BITS to avoid this warning: >>> [ 163.849248] ------------[ cut here ]------------ >>> [ 163.849250] lockdep bfs error:-1 >>> [ 163.849263] WARNING: CPU: 24 PID: 2454 at kernel/locking/lockdep.c:2091 print_bfs_bug+0x27/0x40 >>> ... >>> >>> Signed-off-by: Luis Claudio R. Goncalves >>> --- >>> kernel/locking/lockdep.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c >>> index 58c88220a478a..1cf6d9fdddc9c 100644 >>> --- a/kernel/locking/lockdep.c >>> +++ b/kernel/locking/lockdep.c >>> @@ -2067,6 +2067,9 @@ static noinline void print_bfs_bug(int ret) >>> /* >>> * Breadth-first-search failed, graph got corrupted? >>> */ >>> + if (ret == BFS_EQUEUEFULL) >> This line has an extra space after "ret", but otherwise it looks fine. > Should I send a v2 of the patch with the extra whitespace removed? > > Luis Yes, you should. Other than the extra space, the patch looks good to me too. Reviewed-by: Waiman Long You can also add our review-by tags in your v2 patch. Cheers, Longman > >> Reviewed-by: Boqun Feng >> >> Regards, >> Boqun >> >>> + pr_warn("Increase LOCKDEP_CIRCULAR_QUEUE_BITS to avoid this warning:\n"); >>> + >>> WARN(1, "lockdep bfs error:%d\n", ret); >>> } >>> >>> -- >>> 2.45.2 >>> > ---end quoted text--- >