After removing or reclaiming a guest private page or a control page from a TD, zero the physical page using movdir64b() to enable the kernel to reuse the pages. This is needed for systems with the X86_BUG_TDX_PW_MCE erratum. Introduce the function tdx_quirk_reset_folio() to invoke tdx_quirk_reset_paddr() to convert pages in a huge folio from private back to normal. The pages start from the page at "start_idx" within a "folio", spanning "npages" contiguous PFNs. Signed-off-by: Xiaoyao Li Signed-off-by: Isaku Yamahata Signed-off-by: Yan Zhao --- RFC v3: - Rebased to Sean's cleanup series. - tdx_clear_folio() --> tdx_quirk_reset_folio(). RFC v2: - Add tdx_clear_folio(). - Drop inner loop _tdx_clear_page() and move __mb() outside of the loop. (Rick) - Use C99-style definition of variables inside a for loop. - Note: [1] also changes tdx_clear_page(). RFC v2 is not based on [1] now. [1] https://lore.kernel.org/all/20250724130354.79392-2-adrian.hunter@intel.com RFC v1: - split out, let tdx_clear_page() accept level. --- arch/x86/include/asm/tdx.h | 2 ++ arch/x86/kvm/vmx/tdx.c | 3 ++- arch/x86/virt/vmx/tdx/tdx.c | 11 +++++++++++ 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h index 7f72fd07f4e5..669dd6d99821 100644 --- a/arch/x86/include/asm/tdx.h +++ b/arch/x86/include/asm/tdx.h @@ -147,6 +147,8 @@ static inline bool tdx_supports_demote_nointerrupt(const struct tdx_sys_info *sy } void tdx_quirk_reset_page(struct page *page); +void tdx_quirk_reset_folio(struct folio *folio, unsigned long start_idx, + unsigned long npages); int tdx_guest_keyid_alloc(void); u32 tdx_get_nr_guest_keyids(void); diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index b369f90dbafa..5b499593edff 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1902,7 +1902,8 @@ static void tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn, if (TDX_BUG_ON(err, TDH_PHYMEM_PAGE_WBINVD, kvm)) return; - tdx_quirk_reset_page(page); + tdx_quirk_reset_folio(folio, folio_page_idx(folio, page), + KVM_PAGES_PER_HPAGE(level)); tdx_pamt_put(page); } diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c index b57e00c71384..20708f56b1a0 100644 --- a/arch/x86/virt/vmx/tdx/tdx.c +++ b/arch/x86/virt/vmx/tdx/tdx.c @@ -800,6 +800,17 @@ static void tdx_quirk_reset_paddr(unsigned long base, unsigned long size) mb(); } +void tdx_quirk_reset_folio(struct folio *folio, unsigned long start_idx, + unsigned long npages) +{ + if (WARN_ON_ONCE(start_idx + npages > folio_nr_pages(folio))) + return; + + tdx_quirk_reset_paddr(page_to_phys(folio_page(folio, start_idx)), + npages << PAGE_SHIFT); +} +EXPORT_SYMBOL_GPL(tdx_quirk_reset_folio); + void tdx_quirk_reset_page(struct page *page) { tdx_quirk_reset_paddr(page_to_phys(page), PAGE_SIZE); -- 2.43.2