From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <49108663.4060202@domain.hid> Date: Tue, 04 Nov 2008 18:29:07 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <20081030094458.GA13464@domain.hid> <20081104132227.GA25486@domain.hid> In-Reply-To: <20081104132227.GA25486@domain.hid> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] RTDM driver hangs List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Antonio Garcia Redondo Cc: jagredondo@domain.hid, xenomai@xenomai.org Juan Antonio Garcia Redondo wrote: > Hi all, > > I've been invetigating further the problem and I've found that the > crash occurs in the following situation (now just one process using a > rtdm driver): > > o A real time process call to rtdm_ioctl function. > o The rtdm_ioctl function blocks at rtdm_task_sleep (or any other blocking > system call). > o Arrive a signal which switch the process to executable state. The > blocking system call returns -EINTR. > o Whithout exit the RTDM driver, call to another blocking system call > (rtdm_task_timedwait for instance). This system call returns -EINTR and the > rtdm_ioctl function retuns -EINTR. This is most probably the primary error: You should return to userspace quickly, without further blocking, if a signal is pending. However, the following crash is not OK. Maybe some code path lacks a robustness check, maybe something more seriously is broken. Will try to debug this with your test once time permits. Thanks for reporting, Jan -- Siemens AG, Corporate Technology, CT SE 2 ES-OS Corporate Competence Center Embedded Linux