From 3e8fa263a97079c74880675c451587bb6899e661 Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 19 Oct 2012 13:25:46 +0100 Subject: x86/efi: Fix oops caused by incorrect set_memory_uc() usage Calling __pa() with an ioremap'd address is invalid. If we encounter an efi_memory_desc_t without EFI_MEMORY_WB set in ->attribute we currently call set_memory_uc(), which in turn calls __pa() on a potentially ioremap'd address. On CONFIG_X86_32 this results in the following oops: BUG: unable to handle kernel paging request at f7f22280 IP: [] reserve_ram_pages_type+0x89/0x210 *pdpt = 0000000001978001 *pde = 0000000001ffb067 *pte = 0000000000000000 Oops: 0000 [#1] PREEMPT SMP Modules linked in: Pid: 0, comm: swapper Not tainted 3.0.0-acpi-efi-0805 #3 EIP: 0060:[] EFLAGS: 00010202 CPU: 0 EIP is at reserve_ram_pages_type+0x89/0x210 EAX: 0070e280 EBX: 38714000 ECX: f7814000 EDX: 00000000 ESI: 00000000 EDI: 38715000 EBP: c189fef0 ESP: c189fea8 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 Process swapper (pid: 0, ti=c189e000 task=c18bbe60 task.ti=c189e000) Stack: 80000200 ff108000 00000000 c189ff00 00038714 00000000 00000000 c189fed0 c104f8ca 00038714 00000000 00038715 00000000 00000000 00038715 00000000 00000010 38715000 c189ff48 c1025aff 38715000 00000000 00000010 00000000 Call Trace: [] ? page_is_ram+0x1a/0x40 [] reserve_memtype+0xdf/0x2f0 [] set_memory_uc+0x49/0xa0 [] efi_enter_virtual_mode+0x1c2/0x3aa [] start_kernel+0x291/0x2f2 [] ? loglevel+0x1b/0x1b [] i386_start_kernel+0xbf/0xc8 The only time we can call set_memory_uc() for a memory region is when it is part of the direct kernel mapping. For the case where we ioremap a memory region we must leave it alone. This patch reimplements the fix from e8c7106280a3 ("x86, efi: Calling __pa() with an ioremap()ed address is invalid") which was reverted in e1ad783b12ec because it caused a regression on some MacBooks (they hung at boot). The regression was caused because the commit only marked EFI_RUNTIME_SERVICES_DATA as E820_RESERVED_EFI, when it should have marked all regions that have the EFI_MEMORY_RUNTIME attribute. Despite first impressions, it's not possible to use ioremap_cache() to map all cached memory regions on CONFIG_X86_64 because of the way that the memory map might be configured as detailed in the following bug report, https://bugzilla.redhat.com/show_bug.cgi?id=748516 e.g. some of the EFI memory regions *need* to be mapped as part of the direct kernel mapping. Signed-off-by: Matt Fleming Cc: Matthew Garrett Cc: Zhang Rui Cc: Huang Ying Cc: Keith Packard Cc: Linus Torvalds Cc: Andrew Morton Link: http://lkml.kernel.org/r/1350649546-23541-1-git-send-email-matt@console-pimps.org Signed-off-by: Ingo Molnar --- arch/x86/platform/efi/efi.c | 29 ++++++++++++++++++----------- arch/x86/platform/efi/efi_64.c | 7 +++++-- 2 files changed, 23 insertions(+), 13 deletions(-) (limited to 'arch/x86/platform/efi') diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index aded2a91162a..cb34839c97c5 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -810,6 +810,16 @@ void __iomem *efi_lookup_mapped_addr(u64 phys_addr) return NULL; } +void efi_memory_uc(u64 addr, unsigned long size) +{ + unsigned long page_shift = 1UL << EFI_PAGE_SHIFT; + u64 npages; + + npages = round_up(size, page_shift) / page_shift; + memrange_efi_to_native(&addr, &npages); + set_memory_uc(addr, npages); +} + /* * This function will switch the EFI runtime services to virtual mode. * Essentially, look through the EFI memmap and map every region that @@ -823,7 +833,7 @@ void __init efi_enter_virtual_mode(void) efi_memory_desc_t *md, *prev_md = NULL; efi_status_t status; unsigned long size; - u64 end, systab, addr, npages, end_pfn; + u64 end, systab, end_pfn; void *p, *va, *new_memmap = NULL; int count = 0; @@ -879,10 +889,14 @@ void __init efi_enter_virtual_mode(void) end_pfn = PFN_UP(end); if (end_pfn <= max_low_pfn_mapped || (end_pfn > (1UL << (32 - PAGE_SHIFT)) - && end_pfn <= max_pfn_mapped)) + && end_pfn <= max_pfn_mapped)) { va = __va(md->phys_addr); - else - va = efi_ioremap(md->phys_addr, size, md->type); + + if (!(md->attribute & EFI_MEMORY_WB)) + efi_memory_uc((u64)(unsigned long)va, size); + } else + va = efi_ioremap(md->phys_addr, size, + md->type, md->attribute); md->virt_addr = (u64) (unsigned long) va; @@ -892,13 +906,6 @@ void __init efi_enter_virtual_mode(void) continue; } - if (!(md->attribute & EFI_MEMORY_WB)) { - addr = md->virt_addr; - npages = md->num_pages; - memrange_efi_to_native(&addr, &npages); - set_memory_uc(addr, npages); - } - systab = (u64) (unsigned long) efi_phys.systab; if (md->phys_addr <= systab && systab < end) { systab += md->virt_addr - md->phys_addr; diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index ac3aa54e2654..95fd505dfeb6 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -82,7 +82,7 @@ void __init efi_call_phys_epilog(void) } void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size, - u32 type) + u32 type, u64 attribute) { unsigned long last_map_pfn; @@ -92,8 +92,11 @@ void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size, last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size); if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size) { unsigned long top = last_map_pfn << PAGE_SHIFT; - efi_ioremap(top, size - (top - phys_addr), type); + efi_ioremap(top, size - (top - phys_addr), type, attribute); } + if (!(attribute & EFI_MEMORY_WB)) + efi_memory_uc((u64)(unsigned long)__va(phys_addr), size); + return (void __iomem *)__va(phys_addr); } -- cgit v1.2.3