• Paolo 'Blaisorblade' Giarrusso's avatar
    [PATCH] uml: fix syscall stubs · 4f027241
    Paolo 'Blaisorblade' Giarrusso authored
    Jeff Dike noted that the assembly code for syscall stubs is misassembled with
    GCC 3.2.3: the values copied in registers weren't preserved between one asm()
    and the following one.
    
    So I fixed the thing by rewriting the __asm__ constraints more like unistd.h
    ones.
    
    Note: in syscall6 case I had to add one more instruction (i.e.  moving arg6 in
    eax and shuffling things around) - it's needed for the function to be valid in
    general (we can't load the value from the stack, relative to ebp, because we
    change it), but could be avoided since we actually use a constant as param 6.
    
    The only fix would be to turn stub_syscall6 to a macro and use a "i"
    constraint for arg6 (i.e., specify it's a constant value).
    Signed-off-by: default avatarPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
    Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    4f027241
stub.h 1.82 KB