From: Stefano Stabellini Date: Fri, 18 Feb 2011 11:32:40 +0000 (+0000) Subject: xen: set max_pfn_mapped to the last pfn mapped X-Git-Tag: firefly_0821_release~10186^2~294 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=856460aa905dcc6d11a05a832d487a7b0ce69402;p=firefly-linux-kernel-4.4.55.git xen: set max_pfn_mapped to the last pfn mapped commit 14988a4d350ce3b41ecad4f63c4f44c56f5ae34d upstream. Do not set max_pfn_mapped to the end of the initial memory mappings, that also contain pages that don't belong in pfn space (like the mfn list). Set max_pfn_mapped to the last real pfn mapped in the initial memory mappings that is the pfn backing _end. Signed-off-by: Stefano Stabellini Acked-by: Konrad Rzeszutek Wilk LKML-Reference: Signed-off-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 350a3deedf25..6ec047d827b7 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1658,9 +1658,6 @@ static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) { pte_t pte; - if (pfn > max_pfn_mapped) - max_pfn_mapped = pfn; - if (!pte_none(pte_page[pteidx])) continue; @@ -1704,6 +1701,12 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, pud_t *l3; pmd_t *l2; + /* max_pfn_mapped is the last pfn mapped in the initial memory + * mappings. Considering that on Xen after the kernel mappings we + * have the mappings of some pages that don't exist in pfn space, we + * set max_pfn_mapped to the last real pfn mapped. */ + max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list)); + /* Zap identity mapping */ init_level4_pgt[0] = __pgd(0); @@ -1767,9 +1770,7 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, { pmd_t *kernel_pmd; - max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) + - xen_start_info->nr_pt_frames * PAGE_SIZE + - 512*1024); + max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list)); kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd); memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);