Re: [PATCH 10/13] x86/virt/tdx: Add SEAMCALL wrappers to remove a TD private page

Yan Zhao
2025-01-07T06:54:18Z

On Tue, Jan 07, 2025 at 02:43:11PM +0800, Yan Zhao wrote:
...
> +u64 tdh_phymem_page_wbinvd_hkid(struct page *page, u16 hkid)
> +{
> + struct tdx_module_args args = {};
> +
> + args.rcx = page_to_phys(page) | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
> +
> + return seamcall(TDH_PHYMEM_PAGE_WBINVD, &args);
> +}
For type of hkid is changed from u64 to u16.

Here's a fixup patch to further have tdh_phymem_page_wbinvd_tdr() in [1] and
the tdh_phymem_page_wbinvd_hkid() in this patch to use the common helper
set_hkid_to_hpa().
[1] https://lore.kernel.org/kvm/20250101074959.412696-11-pbonzini@redhat.com/

commit 41f66e12a400516c6a851f0755f8abbe4dacb39b
Author: Yan Zhao <yan.y.zhao@intel.com>
Date: Wed Dec 11 18:11:24 2024 +0800

x86/virt/tdx: Move set_hkid_to_hpa() to x86 common header and use it

Move set_hkid_to_hpa() from KVM TDX to x86 common header and have
tdh_phymem_page_wbinvd_tdr() and tdh_phymem_page_wbinvd_hkid() to use it.

Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>

diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 5420d07ee81c..5f3931e62c06 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -144,7 +144,13 @@ struct tdx_vp {
struct page **tdcx_pages;
};

+static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
+{
+ return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
+}
+
/* SEAMCALL wrappers for creating/destroying/running TDX guests */
+u64 tdh_mng_addcx(struct tdx_td *td, struct page *tdcs_page);
u64 tdh_vp_enter(u64 tdvpr, struct tdx_module_args *args);
u64 tdh_mng_addcx(struct tdx_td *td, struct page *tdcs_page);
u64 tdh_mem_page_add(struct tdx_td *td, gfn_t gfn, struct page *private_page,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index c3a84eb4694a..d86bfcbd6873 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -222,11 +222,6 @@ static inline int pg_level_to_tdx_sept_level(enum pg_level level)
*/
static DEFINE_PER_CPU(struct list_head, associated_tdvcpus);

-static __always_inline hpa_t set_hkid_to_hpa(hpa_t pa, u16 hkid)
-{
- return pa | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
-}
-
static __always_inline union vmx_exit_reason tdexit_exit_reason(struct kvm_vcpu *vcpu)
{
return (union vmx_exit_reason)(u32)(to_tdx(vcpu)->vp_enter_ret);
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 6f002e36e421..0d7a0a27bd3e 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -1930,7 +1930,7 @@ u64 tdh_phymem_page_wbinvd_tdr(struct tdx_td *td)
{
struct tdx_module_args args = {};

- args.rcx = tdx_tdr_pa(td) | ((u64)tdx_global_keyid << boot_cpu_data.x86_phys_bits);
+ args.rcx = set_hkid_to_hpa(tdx_tdr_pa(td), tdx_global_keyid);

return seamcall(TDH_PHYMEM_PAGE_WBINVD, &args);
}
@@ -1940,7 +1940,7 @@ u64 tdh_phymem_page_wbinvd_hkid(struct page *page, u16 hkid)
{
struct tdx_module_args args = {};

- args.rcx = page_to_phys(page) | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
+ args.rcx = set_hkid_to_hpa(page_to_phys(page), hkid);

return seamcall(TDH_PHYMEM_PAGE_WBINVD, &args);
}