Alpha has a clean split between user and kernel address spaces: user space occupies 0x0000000000000000-0x000003ffffffffff (TASK_SIZE), while kernel space uses KSEG and vmalloc regions near the top of the 64-bit address space. These are strictly non-overlapping.
This enables optimizations in BPF and tracing that can skip address range checks when user and kernel pointers are distinguishable by address alone. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Matt Turner <[email protected]> Tested-by: Magnus Lindholm <[email protected]> Reviewed-by: Magnus Lindholm <[email protected]> --- arch/alpha/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index 237ef0c214dd..8f97d6e22b28 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -9,6 +9,7 @@ config ALPHA select ARCH_HAS_DMA_OPS if PCI select ARCH_HAS_FAST_MULTIPLIER select ARCH_HAS_GCOV_PROFILE_ALL + select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE select ARCH_HAS_UBSAN select ARCH_MIGHT_HAVE_PC_PARPORT select ARCH_MIGHT_HAVE_PC_SERIO -- 2.54.0
