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Wed, 29 Jan 2020 07:30:53 -0500 X-MC-Unique: Q5wd-9RhPqyzHHEuMF8AeA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7238E800D41; Wed, 29 Jan 2020 12:30:51 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.70]) by smtp.corp.redhat.com (Postfix) with SMTP id 8A0695C1B5; Wed, 29 Jan 2020 12:30:49 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 29 Jan 2020 13:30:49 +0100 (CET) Date: Wed, 29 Jan 2020 13:30:47 +0100 From: Oleg Nesterov To: madhuparnabhowmik10@gmail.com Message-ID: <20200129123046.GA1726@redhat.com> References: <20200128172008.22665-1-madhuparnabhowmik10@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200128172008.22665-1-madhuparnabhowmik10@gmail.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Cc: paulmck@kernel.org, peterz@infradead.org, linux-kernel@vger.kernel.org, rcu@vger.kernel.org, joel@joelfernandes.org, christian.brauner@ubuntu.com, linux-kernel-mentees@lists.linuxfoundation.org, mingo@kernel.org Subject: Re: [Linux-kernel-mentees] [PATCH] exit.c: Fix Sparse errors and warnings X-BeenThere: linux-kernel-mentees@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-kernel-mentees-bounces@lists.linuxfoundation.org Sender: "Linux-kernel-mentees" On 01/28, madhuparnabhowmik10@gmail.com wrote: > > kernel/exit.c:626:40: warning: incorrect type in assignment > > Signed-off-by: Madhuparna Bhowmik > --- > kernel/exit.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/exit.c b/kernel/exit.c > index bcbd59888e67..c5a9d6360440 100644 > --- a/kernel/exit.c > +++ b/kernel/exit.c > @@ -623,8 +623,8 @@ static void forget_original_parent(struct task_struct *father, > reaper = find_new_reaper(father, reaper); > list_for_each_entry(p, &father->children, sibling) { > for_each_thread(p, t) { > - t->real_parent = reaper; > - BUG_ON((!t->ptrace) != (t->parent == father)); > + rcu_assign_pointer(t->real_parent, reaper); Another case when RCU_INIT_POINTER() makes more sense (although to me it too looks confusing). We didn't modify the new parent. Oleg. _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees