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Mon, 18 Aug 2025 07:45:31 -0400 X-MC-Unique: GUL-TeqQNc2gGJcAky-ovg-1 X-Mimecast-MFC-AGG-ID: GUL-TeqQNc2gGJcAky-ovg_1755517529 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9ADC3180044F; Mon, 18 Aug 2025 11:45:28 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.44.34.24]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 48FE7180028E; Mon, 18 Aug 2025 11:45:22 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 18 Aug 2025 13:44:11 +0200 (CEST) Date: Mon, 18 Aug 2025 13:44:05 +0200 From: Oleg Nesterov To: syzbot Cc: akpm@linux-foundation.org, brauner@kernel.org, dvyukov@google.com, elver@google.com, glider@google.com, jack@suse.cz, kasan-dev@googlegroups.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk, willy@infradead.org Subject: Re: [syzbot] [fs?] [mm?] INFO: task hung in v9fs_file_fsync Message-ID: <20250818114404.GA18626@redhat.com> References: <68a2de8f.050a0220.e29e5.0097.GAE@google.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <68a2de8f.050a0220.e29e5.0097.GAE@google.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 On 08/18, syzbot wrote: > > HEAD commit: 038d61fd6422 Linux 6.16 #syz test: upstream 038d61fd6422 diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c index 339ec4e54778..474fe67f72ac 100644 --- a/net/9p/trans_fd.c +++ b/net/9p/trans_fd.c @@ -666,7 +666,6 @@ static void p9_poll_mux(struct p9_conn *m) static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) { - __poll_t n; int err; struct p9_trans_fd *ts = client->trans; struct p9_conn *m = &ts->conn; @@ -686,13 +685,7 @@ static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) list_add_tail(&req->req_list, &m->unsent_req_list); spin_unlock(&m->req_lock); - if (test_and_clear_bit(Wpending, &m->wsched)) - n = EPOLLOUT; - else - n = p9_fd_poll(m->client, NULL, NULL); - - if (n & EPOLLOUT && !test_and_set_bit(Wworksched, &m->wsched)) - schedule_work(&m->wq); + p9_poll_mux(m); return 0; }