Dear. Chris, Ben. Thanks for your reply. As you know, booting time is important factor in embededd device. If rootdelay is set to 5, kernel will be waiting for 5 sec. root_wait is also looping per 100ms. I have a question. Why is mmc using delayed workqueue ? Thanks. > 2011/3/30 Chris Ball <cjb@xxxxxxxxxx>: >> Hi, >> >> On Tue, Mar 29 2011, Ben Dooks wrote: >>> On Wed, Mar 30, 2011 at 08:33:12AM +0900, NamJae Jeon wrote: >>>> Hi. Chris. >>>> >>>> I found some problem in mmc driver. As you know, in nand trend, emmc >>>> nand is used booting device in embededd product. >>> >>> yeah, a really nasty trend if you ask me. >>> >>>> It means that kernel, rootfs image is stored in emmc nand device. and >>>> when rescaning mmc, mmc driver is working by delay work queue. >>>> >>>> It can be cause "can not mount rootfs". If kernel mounting is faster >>>> than mmc rescan, this problem would occur.. >>>> >>>> I changed to schedule_work instead of mmc_schedule_delayed_work. I can >>>> make patch & test. >>>> >>>> could you tell me your opinion ? >>> >>> Use root_wait on the commandline and it will wait for the root device >>> to become reayd. >> >> Ben's right that you should use "rootwait" (I don't think it works with >> the underscore in the middle), rootdelay=5 if you want the boot to fail >> if the partition isn't mounted after a little extra time, or an initrd >> if you want full control over rootfs mounting. >> >> These parameters are documented in Documentation/kernel-parameters.txt. >> >> Thanks, >> >> - Chris. >> -- >> Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/> >> One Laptop Per Child >> > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
