>>> On 08.01.15 at 14:25, <andrew.coop...@citrix.com> wrote: > do_debug() is capable of correctly dealing with #DB exceptions in guest > context, and indeed needs to be as the 'icebp' instruction skips the DPL > check anyway.
I don't follow: ICEBP doesn't check DPL, right, but what does setting DPL to 3 buy us? Other than for INTO and INT3, we don't want to encourage use of INT $0x01 instructions, nor am I aware of anyone commonly using them. Yet afaict only they would be affected by your change. Actual #DB, just like any other hardware exceptions, don't consider DPL just like ICEBP doesn't. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
