From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Waiman Long , Thomas Gleixner , "Peter Zijlstra (Intel)" , Gavin Schenk , Davidlohr Bueso , Dan Williams , Arnd Bergmann , linux-nfs@vger.kernel.org Subject: [PATCH 4.17 126/220] locking/rwsem: Fix up_read_non_owner() warning with DEBUG_RWSEMS Date: Sun, 1 Jul 2018 18:22:30 +0200 Message-Id: <20180701160913.605670833@linuxfoundation.org> In-Reply-To: <20180701160908.272447118@linuxfoundation.org> References: <20180701160908.272447118@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Waiman Long commit 03eeafdd9ab06a770d42c2b264d50dff7e2f4eee upstream. 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. Fixes: 5149cbac4235 ("locking/rwsem: Add DEBUG_RWSEMS to look for lock/unlock mismatches") Signed-off-by: Waiman Long Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Tested-by: Gavin Schenk Cc: Davidlohr Bueso Cc: Dan Williams Cc: Arnd Bergmann Cc: linux-nfs@vger.kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1527168398-4291-1-git-send-email-longman@redhat.com Signed-off-by: Greg Kroah-Hartman --- kernel/locking/rwsem.c | 1 + 1 file changed, 1 insertion(+) --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -181,6 +181,7 @@ void down_read_non_owner(struct rw_semap might_sleep(); __down_read(sem); + rwsem_set_reader_owned(sem); } EXPORT_SYMBOL(down_read_non_owner);