Re: [libvirt] [PATCH] qemu: Support for overriding NPROC limit

On 04/05/2011 01:46 PM, Jiri Denemark wrote: > On Tue, Apr 05, 2011 at 09:28:00 -0600, Eric Blake wrote: >> On 04/05/2011 08:09 AM, Jiri Denemark wrote: >>> This patch adds max_processes option to qemu.conf which can be used to >>> override system default limit on number of processes that are allowed to >>> be running for qemu user. > > Actually it's important that we call setrlimit() before dropping root > privileges since only such process can increase the limit. Makes sense. > > The NPROC limit is pretty confusing since it logically doesn't fit in > setrlimit and by it gets unnatural behavior as a result of it being set via > setrlimit. It only affects the limit seen by current process which will soon > be executing qemu code. Yeah, there's no real way to confine the absolute number of processes owned by a single uid using just process inheritance; setrlimit only affects the number of processes that can be forked within a given hierarchy. At any rate, this patch is certainly better than what was previously available, I didn't see anything wrong with it, and you answered my question, so: ACK.