Re: [PATCH] x86/mem_sharing: Fix build folloing VM Fork work

[Tamas K Lengyel <tamas@xxxxxxxxxxxxx>]

On Thu, Apr 9, 2020 at 4:05 PM Andrew Cooper <andrew.cooper3@xxxxxxxxxx> wrote:
>
> On 09/04/2020 22:24, Tamas K Lengyel wrote:
> > On Thu, Apr 9, 2020 at 2:48 PM Andrew Cooper <andrew.cooper3@xxxxxxxxxx> 
> > wrote:
> >> A default build fails with:
> >>
> >>   mem_sharing.c: In function ‘copy_special_pages’:
> >>   mem_sharing.c:1649:9: error: ‘HVM_PARAM_STORE_PFN’ undeclared (first use 
> >> in this function)
> >>            HVM_PARAM_STORE_PFN,
> >>            ^~~~~~~~~~~~~~~~~~~
> >>
> >> I suspect this is a rebasing issue with respect to c/s 12f0c69f2709 
> >> "x86/HVM:
> >> reduce hvm.h include dependencies".
> >>
> >> Fixes: 41548c5472a "mem_sharing: VM forking"
> >> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> > So staging definitely compiles for me both with and without
> > CONFIG_MEM_SHARING enabled. By default its off, so this shouldn't even
> > be compiled so I'm curious what's happening in your build. That said,
> > I have no objection to the extra include if it turns out to be
> > actually necessary.
>
> Exact config attached.  I've just double checked that staging fails.
>
> We should get  to the bottom of exactly what is going on here, if it
> isn't the obvious thing.

Strange, with your config it does produce the error. With "echo
CONFIG_MEM_SHARING=y > .config && XEN_CONFIG_EXPERT=y make
olddefconfig && make" it does compile.

Tamas