From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Mon, 14 Sep 2015 23:34:02 +0200 Subject: [Buildroot] [RFC 3/6] system: add mdev-only /dev management (without devtmpfs) In-Reply-To: <87bnd43eph.fsf@dell.be.48ers.dk> References: <1441747734-18730-1-git-send-email-luca@lucaceresoli.net> <1441747734-18730-4-git-send-email-luca@lucaceresoli.net> <55EFF9FF.1020402@mind.be> <55F02630.5050500@lucaceresoli.net> <20150909155427.53f9c8b5@free-electrons.com> <87bnd43eph.fsf@dell.be.48ers.dk> Message-ID: <20150914233402.3575da80@free-electrons.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Dear Peter Korsgaard, On Mon, 14 Sep 2015 22:53:30 +0200, Peter Korsgaard wrote: > >>>>> "Thomas" == Thomas Petazzoni writes: > > Hi, > > > > In principle, it seems better to me if the devices are all set up > > before starting anything else, so if it works, I'm all for S00mdev. The > > only question is whether mdev logs things to syslog, and if so what > > happens to those messages that are emitted before syslog is started. > > It doesn't: > > git grep log mdev.c > mdev.c://usage: "If /dev/mdev.log file exists, debug log will be appended to it." > mdev.c:static void open_mdev_log(const char *seq, unsigned my_pid) > mdev.c: int logfd = open("mdev.log", O_WRONLY | O_APPEND); > mdev.c: if (logfd >= 0) { > mdev.c: xmove_fd(logfd, STDERR_FILENO); > mdev.c: open_mdev_log(seq, my_pid); > > So only to stderr (and /dev/mdev.log if it exists). Then we can safely start mdev before the syslog/klogd stuff, right? Thanks, Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com