From c94cae53f9e564484f906a79be5639fc66e8cb02 Mon Sep 17 00:00:00 2001 From: Eric Trudeau Date: Wed, 4 Dec 2013 11:39:33 +0000 Subject: XEN: Grant table address, xen_hvm_resume_frames, is a phys_addr not a pfn From: Eric Trudeau xen_hvm_resume_frames stores the physical address of the grant table. englighten.c was incorrectly setting it as if it was a page frame number. This caused the table to be mapped into the guest at an unexpected physical address. Additionally, a warning is improved to include the grant table address which failed in xen_remap. Signed-off-by: Eric Trudeau Signed-off-by: Stefano Stabellini --- arch/arm/xen/enlighten.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 83e4f959ee47..6a288c7be49f 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -224,10 +224,10 @@ static int __init xen_guest_init(void) } if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res)) return 0; - xen_hvm_resume_frames = res.start >> PAGE_SHIFT; + xen_hvm_resume_frames = res.start; xen_events_irq = irq_of_parse_and_map(node, 0); pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n", - version, xen_events_irq, xen_hvm_resume_frames); + version, xen_events_irq, (xen_hvm_resume_frames >> PAGE_SHIFT)); xen_domain_type = XEN_HVM_DOMAIN; xen_setup_features(); -- cgit v1.2.3 From a7892f32cc3534d4cc0e64b245fbf47a8e364652 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Wed, 11 Dec 2013 17:02:27 +0000 Subject: arm: xen: foreign mapping PTEs are special. These mappings are in fact special and require special handling in privcmd, which already exists. Failure to mark the PTE as special on arm64 causes all sorts of bad PTE fun. e.g. e.g.: BUG: Bad page map in process xl pte:e0004077b33f53 pmd:4079575003 page:ffffffbce1a2f328 count:1 mapcount:-1 mapping: (null) index:0x0 page flags: 0x4000000000000014(referenced|dirty) addr:0000007fb5259000 vm_flags:040644fa anon_vma: (null) mapping:ffffffc03a6fda58 index:0 vma->vm_ops->fault: privcmd_fault+0x0/0x38 vma->vm_file->f_op->mmap: privcmd_mmap+0x0/0x2c CPU: 0 PID: 2657 Comm: xl Not tainted 3.12.0+ #102 Call trace: [] dump_backtrace+0x0/0x12c [] show_stack+0x14/0x1c [] dump_stack+0x70/0x90 [] print_bad_pte+0x12c/0x1bc [] unmap_single_vma+0x4cc/0x700 [] unmap_vmas+0x68/0xb4 [] unmap_region+0xcc/0x1d4 [] do_munmap+0x218/0x314 [] vm_munmap+0x44/0x64 [] SyS_munmap+0x24/0x34 Where unmap_single_vma contains inlined -> unmap_page_range -> zap_pud_range -> zap_pmd_range -> zap_pte_range -> print_bad_pte. Or: BUG: Bad page state in process xl pfn:4077b4d page:ffffffbce1a2f8d8 count:0 mapcount:-1 mapping: (null) index:0x0 page flags: 0x4000000000000014(referenced|dirty) Modules linked in: CPU: 0 PID: 2657 Comm: xl Tainted: G B 3.12.0+ #102 Call trace: [] dump_backtrace+0x0/0x12c [] show_stack+0x14/0x1c [] dump_stack+0x70/0x90 [] bad_page+0xc4/0x110 [] free_pages_prepare+0xd0/0xd8 [] free_hot_cold_page+0x28/0x178 [] free_hot_cold_page_list+0x38/0x60 [] release_pages+0x190/0x1dc [] unmap_region+0x15c/0x1d4 [] do_munmap+0x218/0x314 [] vm_munmap+0x44/0x64 [] SyS_munmap+0x24/0x34 x86 already gets this correct. 32-bit arm gets away with this because there is not PTE_SPECIAL bit in the PTE there and the vm_normal_page fallback path does the right thing. Signed-off-by: Ian Campbell Signed-off-by: Stefano Stabellini --- arch/arm/xen/enlighten.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm') diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 6a288c7be49f..85501238b425 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -96,7 +96,7 @@ static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, struct remap_data *info = data; struct page *page = info->pages[info->index++]; unsigned long pfn = page_to_pfn(page); - pte_t pte = pfn_pte(pfn, info->prot); + pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot)); if (map_foreign_page(pfn, info->fgmfn, info->domid)) return -EFAULT; -- cgit v1.2.3