The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: e1b8ac3aae589bb57a2c2e49fa76235c687c4d23
Gitweb: https://git.kernel.org/tip/e1b8ac3aae589bb57a2c2e49fa76235c687c4d23
Author: Dexuan Cui <decui@xxxxxxxxxxxxx>
AuthorDate: Mon, 20 May 2024 19:12:38 -07:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Tue, 25 Jun 2024 14:45:22 -07:00
x86/tdx: Support vmalloc() for tdx_enc_status_changed()
When a TDX guest runs on Hyper-V, the hv_netvsc driver's netvsc_init_buf()
allocates buffers using vzalloc(), and needs to share the buffers with the
host OS by calling set_memory_decrypted(), which is not working for
vmalloc() yet. Add the support by handling the pages one by one.
Co-developed-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Acked-by: Kai Huang <kai.huang@xxxxxxxxx>
Cc:stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/all/20240521021238.1803-1-decui%40microsoft.com
---
arch/x86/coco/tdx/tdx.c | 35 ++++++++++++++++++++++++++++-------
1 file changed, 28 insertions(+), 7 deletions(-)
diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index c1cb903..abf3cd5 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -7,6 +7,7 @@
#include <linux/cpufeature.h>
#include <linux/export.h>
#include <linux/io.h>
+#include <linux/mm.h>
#include <asm/coco.h>
#include <asm/tdx.h>
#include <asm/vmx.h>
@@ -778,6 +779,19 @@ static bool tdx_map_gpa(phys_addr_t start, phys_addr_t end, bool enc)
return false;
}
+static bool tdx_enc_status_changed_phys(phys_addr_t start, phys_addr_t end,
+ bool enc)
+{
+ if (!tdx_map_gpa(start, end, enc))
+ return false;
+
+ /* shared->private conversion requires memory to be accepted before use */
+ if (enc)
+ return tdx_accept_memory(start, end);
+
+ return true;
+}
+
/*
* Inform the VMM of the guest's intent for this physical page: shared with
* the VMM or private to the guest. The VMM is expected to change its mapping
@@ -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;
}
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