Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1626291

Re: KASLR causes intermittent boot failures on some systems

From Thomas Garnier <thgarnie@google.com>
Newsgroups linux.kernel
Subject Re: KASLR causes intermittent boot failures on some systems
Date 2017-04-19 17:10 +0200
Message-ID <txZp1-4Zt-45@gated-at.bofh.it> (permalink)
References <ttDn3-8qV-13@gated-at.bofh.it> <txXZU-40g-23@gated-at.bofh.it> <txYMi-4vr-17@gated-at.bofh.it> <txYVZ-4yJ-63@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Wed, Apr 19, 2017 at 7:34 AM, Dan Williams <dan.j.williams@intel.com> wrote:
> Does the randomization ever cross a pgd boundary?

Yes, it can cross a pgd boundary. The original physical memory mapping
might as well but you would need almost 550Gb of memory.

>
> These crashes look very similar to the crashes caused by
> arch_add_memory() racing itself. This issue was fixed in:
>
>     f931ab479dd2 mm: fix devm_memremap_pages crash, use
> mem_hotplug_{begin, done}
>
> ...but that only helps users that call mem_hotplug_begin() to prevent
> concurrent updates.
>

It could be related to page table changes done concurrently or just
done with certain expectations.


-- 
Thomas

Back to linux.kernel | Previous | Next | Find similar | Unroll thread


Thread

Re: KASLR causes intermittent boot failures on some systems Thomas Garnier <thgarnie@google.com> - 2017-04-19 17:10 +0200

csiph-web