From b55b8a9f9b8d11cbc8756243c6ded01f5e618603 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 23 Sep 2013 16:22:47 +0200 Subject: libxc/x86: fix page table creation for huge guests The switch-over logic from one page directory to the next was wrong; it needs to be deferred until we actually reach the last page within a given region, instead of being done when the last entry of a page directory gets started with. Signed-off-by: Jan Beulich Tested-by: Konrad Rzeszutek Wilk Acked-by: Ian Jackson master commit: 06d086832155fc7f5344e9d108b979de34674d11 master date: 2013-09-12 17:41:04 +0200 --- tools/libxc/xc_dom_x86.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/tools/libxc/xc_dom_x86.c b/tools/libxc/xc_dom_x86.c index 126c0f8eeb..41f59d3dd1 100644 --- a/tools/libxc/xc_dom_x86.c +++ b/tools/libxc/xc_dom_x86.c @@ -251,7 +251,7 @@ static int setup_pgtables_x86_32_pae(struct xc_dom_image *dom) l3_pgentry_64_t *l3tab; l2_pgentry_64_t *l2tab = NULL; l1_pgentry_64_t *l1tab = NULL; - unsigned long l3off, l2off, l1off; + unsigned long l3off, l2off = 0, l1off; xen_vaddr_t addr; xen_pfn_t pgpfn; xen_pfn_t l3mfn = xc_dom_p2m_guest(dom, l3pfn); @@ -299,8 +299,6 @@ static int setup_pgtables_x86_32_pae(struct xc_dom_image *dom) l2off = l2_table_offset_pae(addr); l2tab[l2off] = pfn_to_paddr(xc_dom_p2m_guest(dom, l1pfn)) | L2_PROT; - if ( l2off == (L2_PAGETABLE_ENTRIES_PAE - 1) ) - l2tab = NULL; l1pfn++; } @@ -312,8 +310,13 @@ static int setup_pgtables_x86_32_pae(struct xc_dom_image *dom) if ( (addr >= dom->pgtables_seg.vstart) && (addr < dom->pgtables_seg.vend) ) l1tab[l1off] &= ~_PAGE_RW; /* page tables are r/o */ + if ( l1off == (L1_PAGETABLE_ENTRIES_PAE - 1) ) + { l1tab = NULL; + if ( l2off == (L2_PAGETABLE_ENTRIES_PAE - 1) ) + l2tab = NULL; + } } if ( dom->virt_pgtab_end <= 0xc0000000 ) @@ -360,7 +363,7 @@ static int setup_pgtables_x86_64(struct xc_dom_image *dom) l3_pgentry_64_t *l3tab = NULL; l2_pgentry_64_t *l2tab = NULL; l1_pgentry_64_t *l1tab = NULL; - uint64_t l4off, l3off, l2off, l1off; + uint64_t l4off, l3off = 0, l2off = 0, l1off; uint64_t addr; xen_pfn_t pgpfn; @@ -391,8 +394,6 @@ static int setup_pgtables_x86_64(struct xc_dom_image *dom) l3off = l3_table_offset_x86_64(addr); l3tab[l3off] = pfn_to_paddr(xc_dom_p2m_guest(dom, l2pfn)) | L3_PROT; - if ( l3off == (L3_PAGETABLE_ENTRIES_X86_64 - 1) ) - l3tab = NULL; l2pfn++; } @@ -405,8 +406,6 @@ static int setup_pgtables_x86_64(struct xc_dom_image *dom) l2off = l2_table_offset_x86_64(addr); l2tab[l2off] = pfn_to_paddr(xc_dom_p2m_guest(dom, l1pfn)) | L2_PROT; - if ( l2off == (L2_PAGETABLE_ENTRIES_X86_64 - 1) ) - l2tab = NULL; l1pfn++; } @@ -418,8 +417,17 @@ static int setup_pgtables_x86_64(struct xc_dom_image *dom) if ( (addr >= dom->pgtables_seg.vstart) && (addr < dom->pgtables_seg.vend) ) l1tab[l1off] &= ~_PAGE_RW; /* page tables are r/o */ + if ( l1off == (L1_PAGETABLE_ENTRIES_X86_64 - 1) ) + { l1tab = NULL; + if ( l2off == (L2_PAGETABLE_ENTRIES_X86_64 - 1) ) + { + l2tab = NULL; + if ( l3off == (L3_PAGETABLE_ENTRIES_X86_64 - 1) ) + l3tab = NULL; + } + } } return 0; -- cgit v1.2.3