Arnd Bergmann <arnd@xxxxxxxx> writes: > On Friday 06 November 2009, Eric W. Biederman wrote: >> The primary proc path already doesn't need the lock_kernel(). My next >> patch winds up killing the entire binary path and rebuilding on top of >> /proc/sys. Which removes that lock_kernel(). >> >> Which I think elegantly solves all of the sysctl BKL lock issues. > > Yes, that sounds like an excellent plan, but I'm not completely sure > if the lack of the BKL in the procfs case is intentional. As a > particular case that I stumbled over, 'core_pattern' is read > with the BKL held to protect against sysctl changing it, but > it is changed with proc_dostring without the BKL. Then that is a bug. The bottom line is sys_sysctl never gets used in practice, making the proc interface normative. > Most uses of intvec or string seem to be racy and probably need > a proper serialization method anyway. That sounds familiar. Of course in practice the changes are rare enough and are of static variables that don't get reallocated that I would be surprised if the lack of lacking ever causes more more than temporary strange behavior. Eric -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
