Re: waiting 10s before mounting root filesystem?

[Paulo Marques <pmarques@grupopie.com>]

Andrew Morton wrote:
> William Park <opengeometry@yahoo.ca> wrote:
> 
>>-		printk("VFS: Cannot open root device \"%s\" or %s\n",
>> -				root_device_name, b);
>> -		printk("Please append a correct \"root=\" boot option\n");
>> +		if (--tryagain) {
>> +		    printk (KERN_WARNING "VFS: Waiting %dsec for root device...\n", tryagain);
>> +		    ssleep (1);
>> +		    goto retry;
>> +		}
>> +		printk (KERN_CRIT "VFS: Cannot open root device \"%s\" or %s\n", root_device_name, b);
>> +		printk (KERN_CRIT "Please append a correct \"root=\" boot option\n");
> 
> 
> Why is this patch needed?  If it is to offer the user a chance to insert
> the correct medium or to connect the correct device, why not rely upon the
> user doing that thing and then hitting reset?

No, no. The problem is not user interaction.

The problem is that the USB subsystem takes a lot of time to go through 
the hostcontrollers -> hubs -> devices. By the time it finds the USB 
mass storage that is supposed to be used as root filesystem, the kernel 
had already panic'ed.

IMHO the kernel should handle this case just fine, without the need for 
initrd's. After all the user says "my root filesystem is /dev/sda1", and 
the kernel panic's even though the filesystem is there. This doesn't 
seem like a correct bahavior.

-- 
Paulo Marques - www.grupopie.com

"A journey of a thousand miles begins with a single step."
Lao-tzu, The Way of Lao-tzu