Commit 3c6c7061 authored by Suzuki K Poulose's avatar Suzuki K Poulose Committed by Catalin Marinas
Browse files

arm64: rsi: Map unprotected MMIO as decrypted 



Instead of marking every MMIO as shared, check if the given region is
"Protected" and apply the permissions accordingly.

Reviewed-by: default avatarGavin Shan <gshan@redhat.com>
Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: default avatarSteven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20241017131434.40935-6-steven.price@arm.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 37158943

arch/arm64/kernel/rsi.c

+15 −0
Original line number Diff line number Diff line
@@ -6,6 +6,8 @@ 
#include <linux/jump_label.h>

#include <linux/memblock.h>

#include <linux/psci.h>



#include <asm/io.h>

#include <asm/rsi.h>



static struct realm_config config;
@@ -93,6 +95,16 @@ bool __arm64_is_protected_mmio(phys_addr_t base, size_t size) 
}

EXPORT_SYMBOL(__arm64_is_protected_mmio);



static int realm_ioremap_hook(phys_addr_t phys, size_t size, pgprot_t *prot)

{

	if (__arm64_is_protected_mmio(phys, size))

		*prot = pgprot_encrypted(*prot);

	else

		*prot = pgprot_decrypted(*prot);



	return 0;

}



void __init arm64_rsi_init(void)

{

	if (arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_SMC)
@@ -103,6 +115,9 @@ void __init arm64_rsi_init(void) 
		return;

	prot_ns_shared = BIT(config.ipa_bits - 1);



	if (arm64_ioremap_prot_hook_register(realm_ioremap_hook))

		return;



	arm64_rsi_setup_memory();



	static_branch_enable(&rsi_present);