On Thu, 5 Mar 2026, Edgar E. Iglesias wrote: > On Wed, Mar 04, 2026 at 04:07:23PM -0800, Stefano Stabellini wrote: > > On Wed, 4 Mar 2026, Edgar E. Iglesias wrote: > > > From: "Edgar E. Iglesias" <[email protected]> > > > > > > Conditionalize use of the mapcache. This is in preparation > > > to optionally disable the mapcache at runtime. > > > > > > Signed-off-by: Edgar E. Iglesias <[email protected]> > > > --- > > > system/physmem.c | 13 +++++++------ > > > 1 file changed, 7 insertions(+), 6 deletions(-) > > > > > > diff --git a/system/physmem.c b/system/physmem.c > > > index e5ff26acec..64e6d50f8f 100644 > > > --- a/system/physmem.c > > > +++ b/system/physmem.c > > > @@ -578,7 +578,8 @@ MemoryRegion *flatview_translate(FlatView *fv, hwaddr > > > addr, hwaddr *xlat, > > > is_write, true, &as, attrs); > > > mr = section.mr; > > > > > > - if (xen_enabled() && memory_access_is_direct(mr, is_write, attrs)) { > > > + if (xen_map_cache_enabled() && > > > + memory_access_is_direct(mr, is_write, attrs)) { > > > hwaddr page = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - > > > addr; > > > *plen = MIN(page, *plen); > > > } > > > > All the other changes make sense. For this one, the code inside the if > > check is not strictly related to the mapcache. Are you sure it should be > > changed? > > Hi, yes, when the mapcache is on, we limit translations to the current page > because the next page might not be mapped/locked or could be in a different > mapcache bucket with a different virtual address. When mapcache is off, guest > RAM is fully mapped (same as non‑Xen), so we can skip capping plen and allow a > larger mapping. > > Perhaps we should add a comment to clarify?
Yes please! Add a one-line in-code comment, and with that: Reviewed-by: Stefano Stabellini <[email protected]>
