On 14/01/2021 15:23, Jan Beulich wrote: > Forever since the fix for XSA-230 the 2nd of the comments ahead of > fixup_status_for_copy_pin() has been stale - there's nothing specific to > transitive grants there anymore. > > Move the function up, drop the "copy" part from its name again, add a > "readonly" parameter, and use it also on other paths having decremented > one (or not having got to increment any) of the pin counts. > > Signed-off-by: Jan Beulich <jbeul...@suse.com> > > --- a/xen/common/grant_table.c > +++ b/xen/common/grant_table.c > @@ -908,6 +908,25 @@ static int _set_status(const grant_entry > return _set_status_v2(shah, status, rd, act, readonly, mapflag, > ldomid); > } > > +/* > + * The status for a grant may indicate that we're taking more access than > + * the pin requires. Fix up the status to match the pin.
This sentence isn't correct. It will only clear status flags to match a reduction in the pinned references. IOW it cannot be used in the case that a grant goes from unpinned to pinned. How about renaming to clear_status_for_pin() to make this clearer? I don't think it is worth trying to make the operation more generic. If so (and with a suitable adjustment to the comment), Reviewed-by: Andrew Cooper <andrew.coop...@citrix.com>
