Commit e0d8e991 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Michael Ellerman
Browse files

powerpc/book3s64/kuap: Move UAMOR setup to key init function 



UAMOR values are not application-specific. The kernel initializes
its value based on different reserved keys. Remove the thread-specific
UAMOR value and don't switch the UAMOR on context switch.

Move UAMOR initialization to key initialization code and remove
thread_struct.uamor because it is not used anymore.

Before commit: 4a4a5e5d ("powerpc/pkeys: key allocation/deallocation must not change pkey registers")
we used to update uamor based on key allocation and free.

Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-20-aneesh.kumar@linux.ibm.com
parent 000a42b3

arch/powerpc/include/asm/book3s/64/pkeys.h

+2 −0
Original line number Diff line number Diff line
@@ -5,6 +5,8 @@ 


#include <asm/book3s/64/hash-pkey.h>



extern u64 __ro_after_init default_uamor;



static inline u64 vmflag_to_pte_pkey_bits(u64 vm_flags)

{

	if (!mmu_has_feature(MMU_FTR_PKEY))

arch/powerpc/include/asm/processor.h

+0 −1
Original line number Diff line number Diff line
@@ -237,7 +237,6 @@ struct thread_struct { 
#ifdef CONFIG_PPC_MEM_KEYS

	unsigned long	amr;

	unsigned long	iamr;

	unsigned long	uamor;

#endif

#ifdef CONFIG_KVM_BOOK3S_32_HANDLER

	void*		kvm_shadow_vcpu; /* KVM internal data */

arch/powerpc/kernel/ptrace/ptrace-view.c

+21 −6
Original line number Diff line number Diff line
@@ -488,14 +488,21 @@ static int pkey_active(struct task_struct *target, const struct user_regset *reg 
static int pkey_get(struct task_struct *target, const struct user_regset *regset,

		    unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)

{

	int ret;



	BUILD_BUG_ON(TSO(amr) + sizeof(unsigned long) != TSO(iamr));

	BUILD_BUG_ON(TSO(iamr) + sizeof(unsigned long) != TSO(uamor));



	if (!arch_pkeys_enabled())

		return -ENODEV;



	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr,

				   0, ELF_NPKEY * sizeof(unsigned long));

	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr,

				  0, 2 * sizeof(unsigned long));

	if (ret)

		return ret;



	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &default_uamor,

				  2 * sizeof(unsigned long), 3 * sizeof(unsigned long));

	return ret;

}



static int pkey_set(struct task_struct *target, const struct user_regset *regset,
@@ -517,9 +524,17 @@ static int pkey_set(struct task_struct *target, const struct user_regset *regset 
	if (ret)

		return ret;



	/* UAMOR determines which bits of the AMR can be set from userspace. */

	target->thread.amr = (new_amr & target->thread.uamor) |

			     (target->thread.amr & ~target->thread.uamor);

	/*

	 * UAMOR determines which bits of the AMR can be set from userspace.

	 * UAMOR value 0b11 indicates that the AMR value can be modified

	 * from userspace. If the kernel is using a specific key, we avoid

	 * userspace modifying the AMR value for that key by masking them

	 * via UAMOR 0b00.

	 *

	 * Pick the AMR values for the keys that kernel is using. This

	 * will be indicated by the ~default_uamor bits.

	 */

	target->thread.amr = (new_amr & default_uamor) | (target->thread.amr & ~default_uamor);



	return 0;

}

arch/powerpc/kernel/smp.c

+1 −0
Original line number Diff line number Diff line
@@ -59,6 +59,7 @@ 
#include <asm/asm-prototypes.h>

#include <asm/cpu_has_feature.h>

#include <asm/ftrace.h>

#include <asm/kup.h>



#ifdef DEBUG

#include <asm/udbg.h>

arch/powerpc/mm/book3s64/hash_utils.c

+4 −0
Original line number Diff line number Diff line
@@ -1110,6 +1110,10 @@ void hash__early_init_mmu_secondary(void) 
	if (cpu_has_feature(CPU_FTR_ARCH_206)

			&& cpu_has_feature(CPU_FTR_HVMODE))

		tlbiel_all();



#ifdef CONFIG_PPC_MEM_KEYS

	mtspr(SPRN_UAMOR, default_uamor);

#endif

}

#endif /* CONFIG_SMP */

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