lkml.org 
[lkml]   [2006]   [Mar]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [Xen-devel] Re: [RFC, PATCH 0/24] VMI i386 Linux virtualization interface proposal
    Zachary Amsden wrote:
    > Chuck Ebbert wrote:
    >> In-Reply-To: <20060315102522.GA5926@infradead.org>
    >>
    >> On Wed, 15 Mar 2006 10:25:22 +0000, Christoph Hellwig wrote:
    >> I'd like to see a test harness implementation that has no actual
    >> hypervisor functionality and just implements the VMI calls natively.
    >> This could be used to test the interface and would provide a nice
    >> starting point for those who want to write a VMI hypervisor.
    >>
    >
    > I was going to make one yesterday. But Fry's electronics stopped
    > carrying flashable blank PCI cards. :) Anyone know of a vendor?
    It's very practical to just patch Qemu to load a VMI rom as an option
    ROM. That makes such an example VMI ROM very practical without having
    to build a special PCI device.

    Regards,

    Anthony Liguori
    > It is possible to do in a software layer, although it really is a lot
    > easier to have the BIOS take care of all the fuss of finding a place
    > in low memory for you to live, setting up the various memory maps and
    > everything else for you.
    >
    > There is enormous benefit to having such a layer - you have a very
    > power test harness, not just to make sure VMI works, but even more
    > importantly, to inspect and verify the native kernel operation as
    > well. You have a plethora of imporant hooks into the system, which
    > feed you knowledge you can not otherwise gain about which page tables
    > have been made active, when you take IRQs, where the kernel stack lives.
    >
    > All of this is ripe for a debug harness that can verify the kernel
    > doesn't overflow the kernel stack, doesn't write to active page table
    > entries without proper accessors and subsequent invalidations, and
    > obeys the rules that are required for correctness when running under a
    > hypervisor. You probably even want to do hypervisor like things -
    > such as write protecting the kernel page tables so that you can be
    > confident there are no stray raw PTE accesses.
    >
    > We actually found one (harmless on native) in i386, which was enabling
    > NX bit.
    >
    > Zach
    >
    > _______________________________________________
    > Xen-devel mailing list
    > Xen-devel@lists.xensource.com
    > http://lists.xensource.com/xen-devel

    -
    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/

    \
     
     \ /
      Last update: 2006-03-17 19:45    [W:0.028 / U:91.908 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site