Takashi Iwai a écrit : > At Tue, 16 Oct 2012 18:01:13 +0200, > Matthieu CASTET wrote: >> Takashi Iwai a écrit : >>> At Mon, 15 Oct 2012 19:41:40 +0200, >>> Matthieu CASTET wrote: >>>> Hi Takashi, >>>> >>>> But I believe I found other races in the alsa char device handling. With the >>>> attached patch, if you disconnect the usb audio device between "msleep o" and >>>> "msleep o+", you will free the card resource (snd_card_do_free) and then use it [1]. >>>> >>>> I did in in snd_ctl_open, but the same thing could be done in snd_pcm_open, ... >>> OK, we'd need a generic open/close protection. >>> For PCM, there is already a fix in my last patchset, so it should >>> work, but for other devices, the paths are still uncovered. >>> >> I don't think it will work for pcm : the begin of snd_pcm_open is not protected >> by any lock even with your patch >> In snd_open we release sound_mutex before calling file->f_op->open. >> >> The snd_lookup_minor_data and snd_card_file_add should be protected by a lock. >> Attached a patch (pcm.crash) that help to trigger [1]. > > Check out my latest patches in topic/usb-disconnect-fix branch. > It's been fixed there. > Thanks, the first tests seems ok. We will do more strees test. Matthieu -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
