[Xen-devel] size of ctxt.gdt_frames?

To:	xendevel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject:	[Xen-devel] size of ctxt.gdt_frames?
From:	"Tim Wood" <twwood@xxxxxxxxx>
Date:	Tue, 19 Dec 2006 10:29:45 -0500
Delivery-date:	Tue, 19 Dec 2006 07:29:37 -0800
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I think I'm either confused about the gdt_frames variable, or there is
a bug here:

In xen/public/arch-x86_32.h the gdt_frames array is allocated with 16 entries:

189 struct vcpu_guest_context {
...
204     unsigned long gdt_frames[16], gdt_ents; /* GDT (machine
frames, # ents) */
...

however, in the save/restore code, it is referenced as being much larger:

712     for (i = 0; i < ctxt.gdt_ents; i += 512) {
713         pfn = ctxt.gdt_frames[i];
714         if ((pfn >= max_pfn) || (pfn_type[pfn] !=
XEN_DOMCTL_PFINFO_NOTAB)) {
715             ERROR("GDT frame number is bad");
716             goto out;
717         }
718         ctxt.gdt_frames[i] = p2m[pfn];
719     }

(and there is a similar loop in xc_linux_save)

Should lines 713/718 use ctxt.gdt_frames[i/512] ??

-Tim

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[Xen-devel] size of ctxt.gdt_frames?