At Sun, 12 May 2013 21:59:51 +0800, Ming Lei wrote: > > On Thu, May 9, 2013 at 1:51 AM, Takashi Iwai <ti...@suse.de> wrote: > > > > --- > > From: Takashi Iwai <ti...@suse.de> > > Subject: [PATCH v2] firmware: Avoid deadlock of usermodehelper lock at > > shutdown > > > > When a system goes to reboot/shutdown, it tries to disable the > > usermode helper via usermodehelper_disable(). This might be blocked > > when a driver tries to load a firmware beforehand and it's stuck by > > some reason. > > > > In this patch, the firmware class driver registers a reboot notifier > > so that it can abort all pending f/w bufs. Also enable a flag for > > avoiding the call of usermodehelper after the reboot/shutdown starts. > > > > Signed-off-by: Takashi Iwai <ti...@suse.de> > > --- > > drivers/base/firmware_class.c | 40 +++++++++++++++++++++++++++++++++------- > > 1 file changed, 33 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c > > index 4b1f926..972e535 100644 > > --- a/drivers/base/firmware_class.c > > +++ b/drivers/base/firmware_class.c > > @@ -27,6 +27,7 @@ > > #include <linux/pm.h> > > #include <linux/suspend.h> > > #include <linux/syscore_ops.h> > > +#include <linux/reboot.h> > > > > #include <generated/utsrelease.h> > > > > @@ -171,6 +172,7 @@ static struct firmware_buf *__allocate_fw_buf(const > > char *fw_name, > > strcpy(buf->fw_id, fw_name); > > buf->fwc = fwc; > > init_completion(&buf->completion); > > + INIT_LIST_HEAD(&buf->list); > > You should introduce one extra field(such as, 'list_abort') in > 'struct firmware_buf' and the field of 'list' is for firmware caching now.
Yeah, the current code messes it up. Sorry for not resending the right version. I thought it won't conflict but it seems it doesn't work as is. (At least, list_add() would need to be replaced with list_move()). > Also, INIT_LIST_HEAD isn't needed here. Well, I'd recommend to avoid such a mini optimization unless it's really a hot path. It may bite you in the end... thanks, Takashi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
