Messages in this thread | | | Date | Sun, 24 Apr 2005 13:53:10 -0700 | From | Greg KH <> | Subject | Re: [PATCH][RFC][0/4] InfiniBand userspace verbs implementation |
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On Sun, Apr 24, 2005 at 09:23:48AM -0500, Timur Tabi wrote: > Andrew Morton wrote: > > >If your theory is correct then it should be able to demonstrate this > >problem without any special hardware at all: pin some user memory, then > >generate memory pressure then check the contents of those pinned pages. > > I tried that, but I couldn't get it to fail. But that was a while ago, and > I've learned a few things since then, so I'll try again. > > >But if, for the DMA transfer, you're using the array of page*'s which were > >originally obtained from get_user_pages() then it's rather hard to see how > >the kernel could alter the page's contents. > > > >Then again, if mlock() fixes it then something's up. Very odd. > > With mlock(), we don't need to use get_user_pages() at all. Arjan tells me > the only time an mlocked page can move is with hot (un)plug of memory, but > that isn't supported on the systems that we support.
You don't "support" i386 or ia64 or x86-64 or ppc64 systems? What hardware do you support? And what about the fact that you are aiming to get this code into mainline, right? If not, why are you asking here? :)
thanks,
greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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