Re: [Qemu-devel] [PATCH] User mode: Handle x86_64 vsyscall

[Laurent Desnogues <laurent.desnogues@gmail.com>]

On Fri, Feb 5, 2010 at 11:57 PM, Stefan Weil <weil@mail.berlios.de> wrote:
> Laurent Desnogues schrieb:
[...]
>
> I'm still struggling with bntest and other x86_64-linux-user software
> calling any of the vsyscall functions.
>
> Laurent, your vsyscall patch only works on x86_64 hosts.
>
> A lot of software calls time() which uses vsyscall on x86_64 which
> does not work with x86_64-linux-user mode.

I'm not sure I understand what you mean.  Did you try
on some other host and it failed?  Was your host
32-bit?  If so, I'm afraid user-mode will fail for more
reasons than vsyscall.

> So the status of x86_64-linux-user is not more than experimental :-(
>
> I tried to modify x86_64-linux-user to set up a vsyscall page in high
> memory,
> but this seems to be difficult (at least with 32 bit host).
>
> Any hints how this should be done are welcome.

My patch explicitly prevents the linking of the vsyscall
page.

Could you provide more info about your host?


Laurent