On 4/24/2025 11:04 AM, Yan Zhao wrote:
Enhance the SEAMCALL wrapper tdh_mem_page_aug() to support huge pages.
Verify the validity of the level and ensure that the mapping range is fully
contained within the page folio.
As a conservative solution, perform CLFLUSH on all pages to be mapped into
the TD before invoking the SEAMCALL TDH_MEM_PAGE_AUG. This ensures that any
dirty cache lines do not write back later and clobber TD memory.
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
Signed-off-by: Yan Zhao <yan.y.zhao@xxxxxxxxx>
---
arch/x86/virt/vmx/tdx/tdx.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index f5e2a937c1e7..a66d501b5677 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -1595,9 +1595,18 @@ u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct page *page, u
.rdx = tdx_tdr_pa(td),
.r8 = page_to_phys(page),
};
+ unsigned long nr_pages = 1 << (level * 9);
+ struct folio *folio = page_folio(page);
+ unsigned long idx = 0;
u64 ret;
- tdx_clflush_page(page);
+ if (!(level >= TDX_PS_4K && level < TDX_PS_NR) ||
+ (folio_page_idx(folio, page) + nr_pages > folio_nr_pages(folio)))
+ return -EINVAL;
+
+ while (nr_pages--)
+ tdx_clflush_page(nth_page(page, idx++));
Is the following better to save a variable?
while (nr_pages)
tdx_clflush_page(nth_page(page, --nr_pages));
+
ret = seamcall_ret(TDH_MEM_PAGE_AUG, &args);
*ext_err1 = args.rcx;
