From: Juergen Gross <jgross@xxxxxxxx> Sent: Wednesday, April 27, 2022 8:34 AM
Instead of using arch_has_restricted_virtio_memory_access() together
with CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, replace those
with platform_has() and a new platform feature
PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS.
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
V2:
- move setting of PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS in SEV case
to sev_setup_arch().
---
arch/s390/Kconfig | 1 -
arch/s390/mm/init.c | 13 +++----------
arch/x86/Kconfig | 1 -
arch/x86/kernel/cpu/mshyperv.c | 5 ++++-
arch/x86/mm/mem_encrypt.c | 6 ------
arch/x86/mm/mem_encrypt_amd.c | 4 ++++
drivers/virtio/Kconfig | 6 ------
drivers/virtio/virtio.c | 5 ++---
include/linux/platform-feature.h | 3 ++-
include/linux/virtio_config.h | 9 ---------
10 files changed, 15 insertions(+), 38 deletions(-)
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index e084c72104f8..f97a22ae69a8 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -772,7 +772,6 @@ menu "Virtualization"
config PROTECTED_VIRTUALIZATION_GUEST
def_bool n
prompt "Protected virtualization guest support"
- select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
help
Select this option, if you want to be able to run this
kernel as a protected virtualization KVM guest.
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 86ffd0d51fd5..2c3b451813ed 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -31,6 +31,7 @@
#include <linux/cma.h>
#include <linux/gfp.h>
#include <linux/dma-direct.h>
+#include <linux/platform-feature.h>
#include <asm/processor.h>
#include <linux/uaccess.h>
#include <asm/pgalloc.h>
@@ -168,22 +169,14 @@ bool force_dma_unencrypted(struct device *dev)
return is_prot_virt_guest();
}
-#ifdef CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
-
-int arch_has_restricted_virtio_memory_access(void)
-{
- return is_prot_virt_guest();
-}
-EXPORT_SYMBOL(arch_has_restricted_virtio_memory_access);
-
-#endif
-
/* protected virtualization */
static void pv_init(void)
{
if (!is_prot_virt_guest())
return;
+ platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS);
+
/* make sure bounce buffers are shared */
swiotlb_force = SWIOTLB_FORCE;
swiotlb_init(1);
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b0142e01002e..20ac72546ae4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1515,7 +1515,6 @@ config X86_CPA_STATISTICS
config X86_MEM_ENCRYPT
select ARCH_HAS_FORCE_DMA_UNENCRYPTED
select DYNAMIC_PHYSICAL_MASK
- select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
def_bool n
config AMD_MEM_ENCRYPT
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 4b67094215bb..965518b9d14b 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -19,6 +19,7 @@
#include <linux/i8253.h>
#include <linux/random.h>
#include <linux/swiotlb.h>
+#include <linux/platform-feature.h>
#include <asm/processor.h>
#include <asm/hypervisor.h>
#include <asm/hyperv-tlfs.h>
@@ -347,8 +348,10 @@ static void __init ms_hyperv_init_platform(void)
#endif
/* Isolation VMs are unenlightened SEV-based VMs, thus this check: */
if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
- if (hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE)
+ if (hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE) {
cc_set_vendor(CC_VENDOR_HYPERV);
+
platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS);
+ }
}
}
Unless I'm misunderstanding something, the Hyper-V specific change isn't
needed. Hyper-V doesn't support virtio in the first place, so it's a bit
unexpected be setting a virtio-related flag in Hyper-V code. Also, Hyper-V
guests call sev_setup_arch() with CC_ATTR_GUEST_MEM_ENCRYPT set,
so this virtio-related flag will get set anyway via that path.
Attachment:
OpenPGP_0xB0DE9DD628BF132F.asc
Description: OpenPGP public key
Attachment:
OpenPGP_signature
Description: OpenPGP digital signature