Re: [PATCH] mm: mmap: show vm_unmapped_area error log

[Matthew Wilcox]

On Sat, Mar 07, 2020 at 03:47:44PM -0800, Andrew Morton wrote:
> On Fri, 6 Mar 2020 15:16:22 +0900 Jaewon Kim <jaewon31.kim@xxxxxxxxxxx> wrote:
> > Even on 64 bit kernel, the mmap failure can happen for a 32 bit task.
> > Virtual memory space shortage of a task on mmap is reported to userspace
> > as -ENOMEM. It can be confused as physical memory shortage of overall
> > system.

But userspace can trigger this printk.  We don't usually allow printks
under those circumstances, even ratelimited.