On 06/01/2020 15:35, Jan Beulich wrote:
> After dad74b0f9e ("i386: fix handling of Xen entries in final L2 page
> table") and the removal of 32-bit support the function doesn't modify
> state anymore, and hence its name has been misleading. Change its name,
> constify parameters and a local variable, and make it return bool.
>
> Also drop the call to it from mod_l3_entry(): The function explicitly
> disallows 32-bit domains to modify slot 3. This way we also won't
> re-check slot 3 when a slot other than slot 3 changes. Doing so has
> needlessly disallowed making some L2 table recursively link back to an
> L2 used in some L3's 3rd slot, as we check for the type ref count to be
> 1. (Note that allowing dynamic changes of L3 entries in the way we do is
> bogus anyway, as that's not how L3s behave in the native and EPT cases:
> They get re-evaluated only upon CR3 reloads. NPT is different in this
> regard.)
>
> As a result of this we no longer need to play games to get at the start
> of the L3 table.
>
> Additionally move the single remaining call site, allowing to drop one
> is_pv_32bit_domain() invocation and a _PAGE_PRESENT check (in the
> function itself) as well as to exit the loop early (remaining entries
> have all ben set to empty just ahead of this loop).been. > > Further move a BUG_ON() such that in the common case its condition > wouldn't need evaluating. > > Finally, since we're at it, move init_xen_pae_l2_slots() next to the > renamed function, as they really belong together (in fact > init_xen_pae_l2_slots() was [indirectly] broken out of this function). > > Signed-off-by: Jan Beulich <jbeul...@suse.com> Reviewed-by: Andrew Cooper <andrew.coop...@citrix.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
