The TDX module uses a private KeyID as the "global KeyID" for mapping
things like the PAMT and other TDX metadata. This KeyID has already
been reserved when detecting TDX during the kernel early boot.
After the list of "TD Memory Regions" (TDMRs) has been constructed to
cover all TDX-usable memory regions, the next step is to pass them to
the TDX module together with the global KeyID.
Signed-off-by: Kai Huang <[email protected]>
Reviewed-by: Isaku Yamahata <[email protected]>
---
v10 -> v11:
- No update
v9 -> v10:
- Code change due to change static 'tdx_tdmr_list' to local 'tdmr_list'.
v8 -> v9:
- Improved changlog to explain why initializing TDMRs can take long
time (Dave).
- Improved comments around 'next-to-initialize' address (Dave).
v7 -> v8: (Dave)
- Changelog:
- explicitly call out this is the last step of TDX module initialization.
- Trimed down changelog by removing SEAMCALL name and details.
- Removed/trimmed down unnecessary comments.
- Other changes due to 'struct tdmr_info_list'.
v6 -> v7:
- Removed need_resched() check. -- Andi.
---
arch/x86/virt/vmx/tdx/tdx.c | 41 ++++++++++++++++++++++++++++++++++++-
arch/x86/virt/vmx/tdx/tdx.h | 2 ++
2 files changed, 42 insertions(+), 1 deletion(-)
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 0c2dedbc074c..6222a1456ca4 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -26,6 +26,7 @@
#include <linux/pfn.h>
#include <linux/align.h>
#include <linux/sort.h>
+#include <linux/log2.h>
#include <asm/msr-index.h>
#include <asm/msr.h>
#include <asm/archrandom.h>
@@ -902,6 +903,39 @@ static int construct_tdmrs(struct list_head *tmb_list,
return ret;
}
+static int config_tdx_module(struct tdmr_info_list *tdmr_list, u64 global_keyid)
+{
+ u64 *tdmr_pa_array;
+ size_t array_sz;
+ int i, ret;
+
+ /*
+ * TDMRs are passed to the TDX module via an array of physical
+ * addresses of each TDMR. The array itself also has certain
+ * alignment requirement.
+ */
+ array_sz = tdmr_list->nr_consumed_tdmrs * sizeof(u64);
+ array_sz = roundup_pow_of_two(array_sz);
+ if (array_sz < TDMR_INFO_PA_ARRAY_ALIGNMENT)
+ array_sz = TDMR_INFO_PA_ARRAY_ALIGNMENT;
+
+ tdmr_pa_array = kzalloc(array_sz, GFP_KERNEL);
+ if (!tdmr_pa_array)
+ return -ENOMEM;
+
+ for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++)
+ tdmr_pa_array[i] = __pa(tdmr_entry(tdmr_list, i));
+
+ ret = seamcall(TDH_SYS_CONFIG, __pa(tdmr_pa_array),
+ tdmr_list->nr_consumed_tdmrs,
+ global_keyid, 0, NULL, NULL);
+
+ /* Free the array as it is not required anymore. */
+ kfree(tdmr_pa_array);
+
+ return ret;
+}
+
static int init_tdx_module(void)
{
static DECLARE_PADDED_STRUCT(tdsysinfo_struct, tdsysinfo,
@@ -941,16 +975,21 @@ static int init_tdx_module(void)
if (ret)
goto out_free_tdmrs;
+ /* Pass the TDMRs and the global KeyID to the TDX module */
+ ret = config_tdx_module(&tdx_tdmr_list, tdx_global_keyid);
+ if (ret)
+ goto out_free_pamts;
+
/*
* TODO:
*
- * - Configure the TDMRs and the global KeyID to the TDX module.
* - Configure the global KeyID on all packages.
* - Initialize all TDMRs.
*
* Return error before all steps are done.
*/
ret = -EINVAL;
+out_free_pamts:
if (ret)
tdmrs_free_pamt_all(&tdx_tdmr_list);
else
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index e8110e1a9980..7baf0d662b50 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -24,6 +24,7 @@
#define TDH_SYS_INIT 33
#define TDH_SYS_LP_INIT 35
#define TDH_SYS_INFO 32
+#define TDH_SYS_CONFIG 45
struct cmr_info {
u64 base;
@@ -100,6 +101,7 @@ struct tdmr_reserved_area {
} __packed;
#define TDMR_INFO_ALIGNMENT 512
+#define TDMR_INFO_PA_ARRAY_ALIGNMENT 512
struct tdmr_info {
u64 base;
--
2.40.1
On Mon, Jun 05, 2023 at 02:27:27AM +1200, Kai Huang wrote:
> The TDX module uses a private KeyID as the "global KeyID" for mapping
> things like the PAMT and other TDX metadata. This KeyID has already
> been reserved when detecting TDX during the kernel early boot.
>
> After the list of "TD Memory Regions" (TDMRs) has been constructed to
> cover all TDX-usable memory regions, the next step is to pass them to
> the TDX module together with the global KeyID.
>
> Signed-off-by: Kai Huang <[email protected]>
> Reviewed-by: Isaku Yamahata <[email protected]>
Reviewed-by: Kirill A. Shutemov <[email protected]>
--
Kiryl Shutsemau / Kirill A. Shutemov