Commit 25ae981f authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/nohash: Move setup_kuap out of 8xx.c 



In order to reuse it on booke/4xx, move KUAP
setup routine out of 8xx.c

Make them usable on SMP by removing the __init tag
as it is called for each CPU.

And use __prevent_user_access() instead of hard
coding initial lock.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ae35eec3426509efc2b8ae69586c822e2fe2642a.1634627931.git.christophe.leroy@csgroup.eu
parent 937fb700

arch/powerpc/mm/nohash/8xx.c

+0 −21
Original line number Diff line number Diff line
@@ -8,11 +8,7 @@ 
 */



#include <linux/memblock.h>

#include <linux/mmu_context.h>

#include <linux/hugetlb.h>

#include <asm/fixmap.h>

#include <asm/code-patching.h>

#include <asm/inst.h>



#include <mm/mmu_decl.h>
@@ -212,23 +208,6 @@ void __init setup_initial_memory_limit(phys_addr_t first_memblock_base, 
	memblock_set_current_limit(min_t(u64, first_memblock_size, SZ_32M));

}



#ifdef CONFIG_PPC_KUAP

struct static_key_false disable_kuap_key;

EXPORT_SYMBOL(disable_kuap_key);



void setup_kuap(bool disabled)

{

	if (disabled) {

		static_branch_enable(&disable_kuap_key);

		return;

	}



	pr_info("Activating Kernel Userspace Access Protection\n");



	mtspr(SPRN_MD_AP, MD_APG_KUAP);

}

#endif



int pud_clear_huge(pud_t *pud)

{

	 return 0;

arch/powerpc/mm/nohash/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 


ccflags-$(CONFIG_PPC64)	:= $(NO_MINIMAL_TOC)



obj-y				+= mmu_context.o tlb.o tlb_low.o

obj-y				+= mmu_context.o tlb.o tlb_low.o kup.o

obj-$(CONFIG_PPC_BOOK3E_64)  	+= tlb_low_64e.o book3e_pgtable.o

obj-$(CONFIG_40x)		+= 40x.o

obj-$(CONFIG_44x)		+= 44x.o

arch/powerpc/mm/nohash/kup.c

0 → 100644
+31 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * This file contains the routines for initializing kernel userspace protection

 */



#include <linux/export.h>

#include <linux/init.h>

#include <linux/jump_label.h>

#include <linux/printk.h>

#include <linux/smp.h>



#include <asm/kup.h>

#include <asm/smp.h>



#ifdef CONFIG_PPC_KUAP

struct static_key_false disable_kuap_key;

EXPORT_SYMBOL(disable_kuap_key);



void setup_kuap(bool disabled)

{

	if (disabled) {

		if (smp_processor_id() == boot_cpuid)

			static_branch_enable(&disable_kuap_key);

		return;

	}



	pr_info("Activating Kernel Userspace Access Protection\n");



	__prevent_user_access(KUAP_READ_WRITE);

}

#endif