Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[mirror_ubuntu-hirsute-kernel.git] / arch / x86 / xen / mmu_pv.c

diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index a0e2b8c6e5c73c5332597cbed8c6dd298a250cb3..4d62c071b166f65c848a12ca07bfe44ca20e198a 100644 (file)
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -315,7 +315,7 @@ void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
 static pteval_t pte_mfn_to_pfn(pteval_t val)
 {
        if (val & _PAGE_PRESENT) {
-               unsigned long mfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
+               unsigned long mfn = (val & XEN_PTE_MFN_MASK) >> PAGE_SHIFT;
                unsigned long pfn = mfn_to_pfn(mfn);
 
                pteval_t flags = val & PTE_FLAGS_MASK;
@@ -1721,7 +1721,7 @@ static unsigned long __init m2p(phys_addr_t maddr)
 {
        phys_addr_t paddr;
 
-       maddr &= PTE_PFN_MASK;
+       maddr &= XEN_PTE_MFN_MASK;
        paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT;
 
        return paddr;
@@ -1902,6 +1902,18 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
        /* Graft it onto L4[511][510] */
        copy_page(level2_kernel_pgt, l2);
 
+       /*
+        * Zap execute permission from the ident map. Due to the sharing of
+        * L1 entries we need to do this in the L2.
+        */
+       if (__supported_pte_mask & _PAGE_NX) {
+               for (i = 0; i < PTRS_PER_PMD; ++i) {
+                       if (pmd_none(level2_ident_pgt[i]))
+                               continue;
+                       level2_ident_pgt[i] = pmd_set_flags(level2_ident_pgt[i], _PAGE_NX);
+               }
+       }
+
        /* Copy the initial P->M table mappings if necessary. */
        i = pgd_index(xen_start_info->mfn_list);
        if (i && i < pgd_index(__START_KERNEL_map))