kuap.c

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2
 3#include <asm/kup.h>
 4#include <asm/smp.h>
 5
 6void setup_kuap(bool disabled)
 7{
 8	if (!disabled) {
 9		update_user_segments(mfsr(0) | SR_KS);
10		isync();        /* Context sync required after mtsr() */
11		init_mm.context.sr0 |= SR_KS;
12		current->thread.sr0 |= SR_KS;
13	}
14
15	if (smp_processor_id() != boot_cpuid)
16		return;
17
18	if (disabled)
19		cur_cpu_spec->mmu_features &= ~MMU_FTR_KUAP;
20	else
21		pr_info("Activating Kernel Userspace Access Protection\n");
22}