lkml.org 
[lkml]   [2007]   [May]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [RFC PATCH 3/3] boot bzImages under paravirt
    H. Peter Anvin wrote:
    > In 32-bit mode? Surely you're joking, Mr. Feynman!
    >

    Right, yes.

    > What's worse, reloading segments here might be highly unsafe, if the
    > memory previously occupied by the GDT has been overwritten. Keep in
    > mind the GDT is touched on a segment *load*, not on a segment *access*;
    > in areas such as booting that can be a huge difference.
    >

    Yep, suits me. I'm happy for the code to assume that at least %cs and
    %ds are sane; I guess %ss too. We could copy %ds into %[efg]s if we
    want to be sure (since I could imagine a bootloader leaving them in a
    less defined state).

    But if the gdt could be missing altogether, then, yes, we should not
    touch them at all.

    J
    -
    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: 2007-05-04 18:15    [W:4.082 / U:0.028 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site