From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mathieu Ropert <mro@adviseo.fr>
Subject: Trouble using update_va_mapping
Date: Mon, 13 Feb 2006 17:06:47 +0100
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Hi,

i'm trying to run a very simple domU kernel on Xen/x86_64, and i'm 
getting some trouble with update_va_mapping(): when trying to remap some 
page table entry, i find the virtual address still pointing to the same 
machine address after the return of the hypercall.

Here's the interesting part of the code:

        cons = (struct xencons_interface *) addr;
        cons->out_prod = 0x42;

        if (HYPERVISOR_update_va_mapping (addr, 
(xen_start_info->console_mfn  << PAGE_SHIFT) | 0x67, 0))
                BUG ();

        tlb_flush ();

        cons = (struct xencons_interface *) addr;

        if (cons->out_prod == 0x42) /* Fails here */
                BUG ();

I've double-checked hypercalls and tlb_flush() function, all seems fine. 
So my guess is that either i missed something in the docs, or there's 
something wrong with update_va_mapping().


Regards,

Mathieu