On Mon, 15 Aug, at 09:05:45AM, Jan Beulich wrote: > While commit 55f1ea15216 ("efi: Fix for_each_efi_memory_desc_in_map() > for empty memmaps") made an attempt to deal with empty memory maps, it > didn't address the case where the desc_size field never gets set, as is > apparently the case when running under Xen. > > Reported-by: <lists@xxxxxxxxxxxx> > Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > Cc: Jiri Slaby <jslaby@xxxxxxx> > Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> > Tested-by: <lists@xxxxxxxxxxxx> > --- > v2: Add comment. > --- > include/linux/efi.h | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > --- 4.8-rc2/include/linux/efi.h > +++ 4.8-rc2-EFI-memdesc-iterator-Xen/include/linux/efi.h > @@ -946,7 +946,11 @@ extern int efi_memattr_apply_permissions > /* Iterate through an efi_memory_map */ > #define for_each_efi_memory_desc_in_map(m, md) \ > for ((md) = (m)->map; \ > - ((void *)(md) + (m)->desc_size) <= (m)->map_end; \ > + /* \ > + * Leverage wrapping of the calculation to avoid an infinite \ > + * loop when all three values are zero. \ > + */ \ > + ((void *)(md) + (m)->desc_size - 1) < (m)->map_end; \ > (md) = (void *)(md) + (m)->desc_size) > Thanks Jan, applied to the 'urgent' EFI queue and tagged for stable. I'll send it out this week. -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html