On Fri, May 30, 2014 at 12:49:56AM +0200, Kai wrote: > Hello, > > I have recently been playing around with writing a custom filesystem > for Linux, and have been reading the source of other filesystems, and > the functions they call into the linux kernel. > While looking at the function sget in super.c I found something strange. > > before if(test) it takes a spinlock, however there seems to be two > cases where it does not unlock it. > (Kernel 3.14, super.c line 441) > > One: > if(!grab_super(old)) goto retry; > Will jump to before spin_lock(), without releasing it first.
Er... So either grab_super() releases that spinlock, or that thing is screwed. The next obvious step would be to look into grab_super()... > Two: > And if it finds an old sb, it will return without releasing the lock. ... unless something it calls does just that. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
