Re: [Xen-devel] [PATCH v11 6/9] xen: Add ring 3 vmware_port support

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 22.05.15 at 17:50, <dslutz@xxxxxxxxxxx> wrote:
> Summary is that VMware treats "in (%dx),%eax" (or "out %eax,(%dx)")
> to port 0x5658 specially.  Note: since many operations return data
> in EAX, "in (%dx),%eax" is the one to use.  The other lengths like
> "in (%dx),%al" will still do things, only AL part of EAX will be
> changed.  For "out %eax,(%dx)" of all lengths, EAX will remain
> unchanged.
> 
> This instruction is allowed to be used from ring 3.  To
> support this the vmexit for GP needs to be enabled.  I have not
> fully tested that nested HVM is doing the right thing for this.
> 
> Enable no-fault of pio in x86_emulate for VMware port
> 
> Also adjust the emulation registers after doing a VMware
> backdoor operation.
> 
> Add new routine hvm_emulate_one_gp() to be used by the #GP fault
> handler.
> 
> Some of the best info is at:
> 
> https://sites.google.com/site/chitchatvmback/backdoor 
> 
> Signed-off-by: Don Slutz <dslutz@xxxxxxxxxxx>

As there don't seem to be enough convincing arguments for this to
be worthwhile, I'm going to drop this and subsequent patches from
my list of things to look at. Would you mind following George's (at
least I think it was him) advice to post a shortened series with all
review comments taken care of, so that at least the ring 0 pieces
could go in for 4.6?

Thanks, Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel