diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/mm/init.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 8490ed2917ff..2b28d77e29a0 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -282,7 +282,21 @@ static void __init fdt_enforce_memory_region(void) void __init arm64_memblock_init(void) { - const s64 linear_region_size = PAGE_END - _PAGE_OFFSET(vabits_actual); + s64 linear_region_size = PAGE_END - _PAGE_OFFSET(vabits_actual); + + /* + * Corner case: 52-bit VA capable systems running KVM in nVHE mode may + * be limited in their ability to support a linear map that exceeds 51 + * bits of VA space, depending on the placement of the ID map. Given + * that the placement of the ID map may be randomized, let's simply + * limit the kernel's linear map to 51 bits as well if we detect this + * configuration. + */ + if (IS_ENABLED(CONFIG_KVM) && vabits_actual == 52 && + is_hyp_mode_available() && !is_kernel_in_hyp_mode()) { + pr_info("Capping linear region to 51 bits for KVM in nVHE mode on LVA capable hardware.\n"); + linear_region_size = min_t(u64, linear_region_size, BIT(51)); + } /* Handle linux,usable-memory-range property */ fdt_enforce_memory_region(); |