From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next] net: bridge: add helper to call /sbin/bridge-stp Date: Tue, 13 Sep 2016 11:22:42 -0400 (EDT) Message-ID: <20160913.112242.2097095000095740530.davem@davemloft.net> References: <20160908165043.31042-1-vivien.didelot@savoirfairelinux.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@savoirfairelinux.com, stephen@networkplumber.org To: vivien.didelot@savoirfairelinux.com Return-path: In-Reply-To: <20160908165043.31042-1-vivien.didelot@savoirfairelinux.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Vivien Didelot Date: Thu, 8 Sep 2016 12:50:43 -0400 > If /sbin/bridge-stp is available on the system, bridge tries to execute > it instead of the kernel implementation when starting/stopping STP. > > If anything goes wrong with /sbin/bridge-stp, bridge silently falls back > to kernel STP, making hard to debug userspace STP. > > This patch adds a br_stp_call_user helper to start/stop userspace STP > and debug errors from the program: abnormal exit status is stored in the > lower byte and normal exit status is stored in higher byte. > > Below is a simple example on a kernel with dynamic debug enabled: > > # ln -s /bin/false /sbin/bridge-stp > # brctl stp br0 on > br0: failed to start userspace STP (256) > # dmesg > br0: /sbin/bridge-stp exited with code 1 > br0: failed to start userspace STP (256) > br0: using kernel STP > > Signed-off-by: Vivien Didelot Applied.