Petersson, Mats
2006-Nov-29 16:05 UTC
[Xen-devel] Getting Machine Physical address from page-fault CR2...
I''m trying to write a piece of code to check writes to MMIO-space (as part of the Configuration Change Verifier, as discussed at the Security Mini-summit at Summer Xen-Summit in San Jose some weeks back). This code needs to check if a physical address matches some list of known physical addresses... My problem right now is that the method I thought would work for translating the value in CR2 (after some other initial checking - like that the page is actually present), doesn''t work... I tried something along the lines of: traps.c: do_page_fault(): pa = shadow_gva_to_gpa(current, addr); /* addr = read_cr2() earlier in the code */ It appeats that current->arch.shadow.mode is sometimes NULL, which isn''t what I expected... Is there some other (better?) way to achieve this? I mean aside from walking the page-table? -- Mats _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel