From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:45260 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751629AbeFSXJ6 (ORCPT ); Tue, 19 Jun 2018 19:09:58 -0400 Subject: Re: [PATCH] locking/rwsem: Fix up_read_non_owner() warning with DEBUG_RWSEMS To: Ingo Molnar , Peter Zijlstra , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, Davidlohr Bueso , Dan Williams , Arnd Bergmann , linux-nfs@vger.kernel.org, =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= References: <1527168398-4291-1-git-send-email-longman@redhat.com> From: Waiman Long Message-ID: Date: Wed, 20 Jun 2018 07:09:54 +0800 MIME-Version: 1.0 In-Reply-To: <1527168398-4291-1-git-send-email-longman@redhat.com> Content-Type: text/plain; charset=utf-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 05/24/2018 09:26 PM, Waiman Long wrote: > It was found that the use of up_read_non_owner() in NFS was causing > the following warning when DEBUG_RWSEMS was configured. > > DEBUG_LOCKS_WARN_ON(sem->owner != ((struct task_struct *)(1UL << 0))) > > Looking into the rwsem.c file, it was discovered that the corresponding > down_read_non_owner() function was not setting the owner field properly. > This is fixed now, and the warning should be gone. > > Signed-off-by: Waiman Long > --- > kernel/locking/rwsem.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c > index bc1e507..776308d 100644 > --- a/kernel/locking/rwsem.c > +++ b/kernel/locking/rwsem.c > @@ -181,6 +181,7 @@ void down_read_non_owner(struct rw_semaphore *sem) > might_sleep(); > tch > __down_read(sem); > + rwsem_set_reader_owned(sem); > } > > EXPORT_SYMBOL(down_read_non_owner); Since the 4.18 merge window has been closed. Can that patch be merged upstream? Cheers, Longman