base_disallow_mask is calculated once in arch_init_memory() and never changes thereafter. Write-protect it at runtime.
Signed-off-by: Andrew Cooper <[email protected]> --- CC: Jan Beulich <[email protected]> CC: Roger Pau Monné <[email protected]> --- xen/arch/x86/mm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c index 0ecea0f707b2..95795567f2a5 100644 --- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -150,7 +150,8 @@ bool __read_mostly machine_to_phys_mapping_valid; struct rangeset *__read_mostly mmio_ro_ranges; -static uint32_t base_disallow_mask; +static uint32_t __ro_after_init base_disallow_mask; + /* Global bit is allowed to be set on L1 PTEs. Intended for user mappings. */ #define L1_DISALLOW_MASK ((base_disallow_mask | _PAGE_GNTTAB) & ~_PAGE_GLOBAL) -- 2.39.2
