On Thu, Nov 26, 2015 at 08:02:35PM +0100, Michael Holzheu wrote: > On Thu, 26 Nov 2015 19:02:28 +0100 > Petr Tesarik <ptesarik at suse.cz> wrote: > > > On Thu, 26 Nov 2015 18:32:31 +0100 > > Michael Holzheu <holzheu at linux.vnet.ibm.com> wrote: > > > > > Hi Simon again, > > > > > > After a bit more thinking: In theory mmap() could also return NULL. > > > Therefore the following fix is probably the better one ... > > > > No, if you let the kernel choose the address (i.e. call mmap with NULL > > addr), it will return at least PAGE_SIZE (and a higher limit is usually > > enforced by sys.vm.mmap_min_addr sysctl). Admittedly the limit is set > > in arch-specific code, so theoretically there can be an architecture > > which sets the limit to 0, but I doubt it, because it would break too > > many assumptions in user space (for example gcc assumes that > > dereferencing a NULL pointer terminates a process). > > > > In short, this other fix is just as good as the previous one. > > Hi Petr, > > Thanks for clarification! I still would vote for the second one ;-) Thanks, I have applied that version.
