Hello, This is a proposal for an alternative fix for XSA-369 that instead of special casing XEN_UNPOPULATED_ALLOC to size the p2m relies on making XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on the generic MEMORY_HOTPLUG option rather than XEN_BALLOON_MEMORY_HOTPLUG.
I think this is safer, as we don't want to be special casing any option that pulls in generic MEMORY_HOTPLUG without XEN_BALLOON_MEMORY_HOTPLUG. Without this we would also need to at least special case ZONE_DEVICE which also relies on MEMORY_HOTPLUG, and is what pulls the generic MEMORY_HOTPLUG option even when XEN_BALLOON_MEMORY_HOTPLUG is disabled with XEN_UNPOPULATED_ALLOC. Thanks, Roger. Roger Pau Monne (2): xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on MEMORY_HOTPLUG Revert "xen: fix p2m size in dom0 for disabled memory hotplug case" arch/x86/include/asm/xen/page.h | 12 ------------ arch/x86/xen/p2m.c | 7 ++----- arch/x86/xen/setup.c | 16 ++++++++++++++-- drivers/xen/Kconfig | 4 ++-- 4 files changed, 18 insertions(+), 21 deletions(-) -- 2.30.1