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. Two: And if it finds an old sb, it will return without releasing the lock. This code seems to be the same in 3.14 and in 2.6 I might just be missing how the spin_lock works, and if so I'm sorry. But this seems really strange to me. Would this not potentially cause a deadlock on sb_lock? -- 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/
