Commit 32cb4d02 authored by Tom Lendacky's avatar Tom Lendacky Committed by Borislav Petkov
Browse files

x86/sme: Replace occurrences of sme_active() with cc_platform_has() 



Replace uses of sme_active() with the more generic cc_platform_has()
using CC_ATTR_HOST_MEM_ENCRYPT. If future support is added for other
memory encryption technologies, the use of CC_ATTR_HOST_MEM_ENCRYPT
can be updated, as required.

This also replaces two usages of sev_active() that are really geared
towards detecting if SME is active.

Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210928191009.32551-6-bp@alien8.de
parent bfebd37e

arch/x86/include/asm/kexec.h

+1 −1
Original line number Diff line number Diff line
@@ -129,7 +129,7 @@ relocate_kernel(unsigned long indirection_page, 
		unsigned long page_list,

		unsigned long start_address,

		unsigned int preserve_context,

		unsigned int sme_active);

		unsigned int host_mem_enc_active);

#endif



#define ARCH_HAS_KIMAGE_ARCH

arch/x86/include/asm/mem_encrypt.h

+0 −2
Original line number Diff line number Diff line
@@ -51,7 +51,6 @@ void __init mem_encrypt_free_decrypted_mem(void); 
void __init mem_encrypt_init(void);



void __init sev_es_init_vc_handling(void);

bool sme_active(void);

bool sev_active(void);

bool sev_es_active(void);
@@ -76,7 +75,6 @@ static inline void __init sme_encrypt_kernel(struct boot_params *bp) { } 
static inline void __init sme_enable(struct boot_params *bp) { }



static inline void sev_es_init_vc_handling(void) { }

static inline bool sme_active(void) { return false; }

static inline bool sev_active(void) { return false; }

static inline bool sev_es_active(void) { return false; }

arch/x86/kernel/machine_kexec_64.c

+8 −7
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/suspend.h>

#include <linux/vmalloc.h>

#include <linux/efi.h>

#include <linux/cc_platform.h>



#include <asm/init.h>

#include <asm/tlbflush.h>
@@ -358,7 +359,7 @@ void machine_kexec(struct kimage *image) 
				       (unsigned long)page_list,

				       image->start,

				       image->preserve_context,

				       sme_active());

				       cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT));



#ifdef CONFIG_KEXEC_JUMP

	if (image->preserve_context)
@@ -569,12 +570,12 @@ void arch_kexec_unprotect_crashkres(void) 
 */

int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)

{

	if (sev_active())

	if (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))

		return 0;



	/*

	 * If SME is active we need to be sure that kexec pages are

	 * not encrypted because when we boot to the new kernel the

	 * If host memory encryption is active we need to be sure that kexec

	 * pages are not encrypted because when we boot to the new kernel the

	 * pages won't be accessed encrypted (initially).

	 */

	return set_memory_decrypted((unsigned long)vaddr, pages);
@@ -582,12 +583,12 @@ int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) 


void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)

{

	if (sev_active())

	if (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))

		return;



	/*

	 * If SME is active we need to reset the pages back to being

	 * an encrypted mapping before freeing them.

	 * If host memory encryption is active we need to reset the pages back

	 * to being an encrypted mapping before freeing them.

	 */

	set_memory_encrypted((unsigned long)vaddr, pages);

}

arch/x86/kernel/pci-swiotlb.c

+4 −5
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ 
#include <linux/swiotlb.h>

#include <linux/memblock.h>

#include <linux/dma-direct.h>

#include <linux/mem_encrypt.h>

#include <linux/cc_platform.h>



#include <asm/iommu.h>

#include <asm/swiotlb.h>
@@ -45,11 +45,10 @@ int __init pci_swiotlb_detect_4gb(void) 
		swiotlb = 1;



	/*

	 * If SME is active then swiotlb will be set to 1 so that bounce

	 * buffers are allocated and used for devices that do not support

	 * the addressing range required for the encryption mask.

	 * Set swiotlb to 1 so that bounce buffers are allocated and used for

	 * devices that can't support DMA to encrypted memory.

	 */

	if (sme_active())

	if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))

		swiotlb = 1;



	return swiotlb;

arch/x86/kernel/relocate_kernel_64.S

+1 −1
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ SYM_CODE_START_NOALIGN(relocate_kernel) 
	 * %rsi page_list

	 * %rdx start address

	 * %rcx preserve_context

	 * %r8  sme_active

	 * %r8  host_mem_enc_active

	 */



	/* Save the CPU context, used for jumping back */