On 10/11/24 11:19 PM, Catalin Marinas wrote:
On Tue, Oct 08, 2024 at 10:31:06AM +1000, Gavin Shan wrote:
On 10/5/24 12:43 AM, Steven Price wrote:
diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c
index d7bba4cee627..f1add76f89ce 100644
--- a/arch/arm64/kernel/rsi.c
+++ b/arch/arm64/kernel/rsi.c
@@ -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>
struct realm_config config;
@@ -92,6 +94,16 @@ 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;
+}
+
We probably need arm64_is_mmio_private() here, meaning arm64_is_protected_mmio() isn't
sufficient to avoid invoking SMCCC call SMC_RSI_IPA_STATE_GET in a regular guest where
realm capability isn't present.
I think we get away with this since the hook won't be registered in a
normal guest (done from arm64_rsi_init()). So the additional check in
arm64_is_mmio_private() is unnecessary.
Indeed. I missed the point that the hook won't be registered for a normal
guest. So we're good and safe.
Thanks,
Gavin
