Messages in this thread | | | From | Dmitry Vyukov <> | Date | Mon, 30 Mar 2020 10:38:50 +0200 | Subject | Re: [PATCH] UML: add support for KASAN under x86_64 |
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On Mon, Mar 30, 2020 at 9:44 AM Johannes Berg <johannes@sipsolutions.net> wrote: > > On Fri, 2020-03-20 at 16:18 +0100, Dmitry Vyukov wrote: > > > > > Wait ... Now you say 0x7fbfffc000, but that is almost fine? I think you > > > confused the values - because I see, on userspace, the following: > > > > Oh, sorry, I copy-pasted wrong number. I meant 0x7fff8000. > > Right, ok. > > > Then I would expect 0x1000 0000 0000 to work, but you say it doesn't... > > So it just occurred to me - as I was mentioning this whole thing to > Richard - that there's probably somewhere some check about whether some > space is userspace or not. > > I'm beginning to think that we shouldn't just map this outside of the > kernel memory system, but properly treat it as part of the memory that's > inside. And also use KASAN_VMALLOC. > > We can probably still have it at 0x7fff8000, just need to make sure we > actually map it? I tried with vm_area_add_early() but it didn't really > work once you have vmalloc() stuff...
But we do mmap it, no? See kasan_init() -> kasan_map_memory() -> mmap.
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