Re: [PATCH] x86/tdx: Support vmalloc() for tdx_enc_status_changed()
From: Kirill A. Shutemov <hidden>
Date: 2024-06-28 10:04:47
Also in:
linux-hyperv, lkml, stable
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
On Mon, May 20, 2024 at 07:12:38PM -0700, Dexuan Cui wrote:
quoted hunk ↗ jump to hunk
@@ -785,15 +799,22 @@ static bool tdx_map_gpa(phys_addr_t start, phys_addr_t end, bool enc) */ static bool tdx_enc_status_changed(unsigned long vaddr, int numpages, bool enc) { - phys_addr_t start = __pa(vaddr); - phys_addr_t end = __pa(vaddr + numpages * PAGE_SIZE); + unsigned long start = vaddr; + unsigned long end = start + numpages * PAGE_SIZE; + unsigned long step = end - start; + unsigned long addr; - if (!tdx_map_gpa(start, end, enc)) - return false; + /* Step through page-by-page for vmalloc() mappings */ + if (is_vmalloc_addr((void *)vaddr)) + step = PAGE_SIZE; - /* shared->private conversion requires memory to be accepted before use */ - if (enc) - return tdx_accept_memory(start, end); + for (addr = start; addr < end; addr += step) { + phys_addr_t start_pa = slow_virt_to_phys((void *)addr); + phys_addr_t end_pa = start_pa + step; + + if (!tdx_enc_status_changed_phys(start_pa, end_pa, enc)) + return false; + } return true; }
This patch collied with kexec changes. tdx_kexec_finish() calls tdx_enc_status_changed() after clearing pte, so slow_virt_to_phys() crashes on in. Daxuan, could you check if the fixup below works for you on vmalloc addresses?
diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index ef8ec2425998..5e455c883bcc 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c@@ -813,8 +813,15 @@ static bool tdx_enc_status_changed(unsigned long vaddr, int numpages, bool enc) step = PAGE_SIZE; for (addr = start; addr < end; addr += step) { - phys_addr_t start_pa = slow_virt_to_phys((void *)addr); - phys_addr_t end_pa = start_pa + step; + phys_addr_t start_pa; + phys_addr_t end_pa; + + if (virt_addr_valid(addr)) + start_pa = __pa(addr); + else + start_pa = slow_virt_to_phys((void *)addr); + + end_pa = start_pa + step; if (!tdx_enc_status_changed_phys(start_pa, end_pa, enc)) return false;
--
Kiryl Shutsemau / Kirill A. Shutemov