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    SubjectRe: [kvm-devel] [PATCH] KVM: Avoid using vmx instruction directly
    Arnd Bergmann wrote:
    > On Thursday 09 November 2006 15:52, Avi Kivity wrote:
    >
    >> Wouldn't that make inline assembly useless? Suppose the contents is
    >> itself a pointer. What about the pointed-to contents?
    >>
    >> e.g.
    >>
    >> int x = 3;
    >> int *y = &x;
    >> int z;
    >>
    >> asm ("mov %1, %%rax; movl (%%rax), %0" : "=r"(z) : "g"(y) : "rax");
    >> assert(z == 3);
    >>
    >
    > Same here, you need to tell gcc what is really accessed, like
    >
    > asm ("mov %1, %%rax; movl (%%rax), %0" : "=r"(z) : "g"(y), "m"(*y) : "rax");
    >
    > I know that the s390 kernel developers have hit that problem
    > frequently with inline assemblies. It may be that it's harder
    > to hit on x86, because there are fewer registers available and
    > data therefore tends to spill to the stack.
    >

    I'll update my tree to reflect this. Thanks.

    --
    error compiling committee.c: too many arguments to function

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