linux/arch/x86/platform/efi/efi_64.c

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/*
* x86_64 specific EFI support functions
* Based on Extensible Firmware Interface Specification version 1.0
*
* Copyright (C) 2005-2008 Intel Co.
* Fenghua Yu <fenghua.yu@intel.com>
* Bibo Mao <bibo.mao@intel.com>
* Chandramouli Narayanan <mouli@linux.intel.com>
* Huang Ying <ying.huang@intel.com>
*
* Code to convert EFI to E820 map has been implemented in elilo bootloader
* based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
* is setup appropriately for EFI runtime code.
* - mouli 06/14/2007.
*
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/bootmem.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/efi.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/reboot.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/e820.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/proto.h>
#include <asm/efi.h>
#include <asm/cacheflush.h>
#include <asm/fixmap.h>
static pgd_t save_pgd __initdata;
static unsigned long efi_flags __initdata;
static void __init early_code_mapping_set_exec(int executable)
{
efi_memory_desc_t *md;
void *p;
if (!(__supported_pte_mask & _PAGE_NX))
return;
x86, efi: Retain boot service code until after switching to virtual mode UEFI stands for "Unified Extensible Firmware Interface", where "Firmware" is an ancient African word meaning "Why do something right when you can do it so wrong that children will weep and brave adults will cower before you", and "UEI" is Celtic for "We missed DOS so we burned it into your ROMs". The UEFI specification provides for runtime services (ie, another way for the operating system to be forced to depend on the firmware) and we rely on these for certain trivial tasks such as setting up the bootloader. But some hardware fails to work if we attempt to use these runtime services from physical mode, and so we have to switch into virtual mode. So far so dreadful. The specification makes it clear that the operating system is free to do whatever it wants with boot services code after ExitBootServices() has been called. SetVirtualAddressMap() can't be called until ExitBootServices() has been. So, obviously, a whole bunch of EFI implementations call into boot services code when we do that. Since we've been charmingly naive and trusted that the specification may be somehow relevant to the real world, we've already stuffed a picture of a penguin or something in that address space. And just to make things more entertaining, we've also marked it non-executable. This patch allocates the boot services regions during EFI init and makes sure that they're executable. Then, after SetVirtualAddressMap(), it discards them and everyone lives happily ever after. Except for the ones who have to work on EFI, who live sad lives haunted by the knowledge that someone's eventually going to write yet another firmware specification. [ hpa: adding this to urgent with a stable tag since it fixes currently-broken hardware. However, I do not know what the dependencies are and so I do not know which -stable versions this may be a candidate for. ] Signed-off-by: Matthew Garrett <mjg@redhat.com> Link: http://lkml.kernel.org/r/1306331593-28715-1-git-send-email-mjg@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: <stable@kernel.org>
2011-05-25 21:53:13 +08:00
/* Make EFI service code area executable */
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
x86, efi: Retain boot service code until after switching to virtual mode UEFI stands for "Unified Extensible Firmware Interface", where "Firmware" is an ancient African word meaning "Why do something right when you can do it so wrong that children will weep and brave adults will cower before you", and "UEI" is Celtic for "We missed DOS so we burned it into your ROMs". The UEFI specification provides for runtime services (ie, another way for the operating system to be forced to depend on the firmware) and we rely on these for certain trivial tasks such as setting up the bootloader. But some hardware fails to work if we attempt to use these runtime services from physical mode, and so we have to switch into virtual mode. So far so dreadful. The specification makes it clear that the operating system is free to do whatever it wants with boot services code after ExitBootServices() has been called. SetVirtualAddressMap() can't be called until ExitBootServices() has been. So, obviously, a whole bunch of EFI implementations call into boot services code when we do that. Since we've been charmingly naive and trusted that the specification may be somehow relevant to the real world, we've already stuffed a picture of a penguin or something in that address space. And just to make things more entertaining, we've also marked it non-executable. This patch allocates the boot services regions during EFI init and makes sure that they're executable. Then, after SetVirtualAddressMap(), it discards them and everyone lives happily ever after. Except for the ones who have to work on EFI, who live sad lives haunted by the knowledge that someone's eventually going to write yet another firmware specification. [ hpa: adding this to urgent with a stable tag since it fixes currently-broken hardware. However, I do not know what the dependencies are and so I do not know which -stable versions this may be a candidate for. ] Signed-off-by: Matthew Garrett <mjg@redhat.com> Link: http://lkml.kernel.org/r/1306331593-28715-1-git-send-email-mjg@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: <stable@kernel.org>
2011-05-25 21:53:13 +08:00
if (md->type == EFI_RUNTIME_SERVICES_CODE ||
md->type == EFI_BOOT_SERVICES_CODE)
efi_set_executable(md, executable);
}
}
void __init efi_call_phys_prelog(void)
{
unsigned long vaddress;
early_code_mapping_set_exec(1);
local_irq_save(efi_flags);
vaddress = (unsigned long)__va(0x0UL);
save_pgd = *pgd_offset_k(0x0UL);
set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress));
__flush_tlb_all();
}
void __init efi_call_phys_epilog(void)
{
/*
* After the lock is released, the original page table is restored.
*/
set_pgd(pgd_offset_k(0x0UL), save_pgd);
__flush_tlb_all();
local_irq_restore(efi_flags);
early_code_mapping_set_exec(0);
}
void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
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: [<c10257b9>] 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:[<c10257b9>] 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: [<c104f8ca>] ? page_is_ram+0x1a/0x40 [<c1025aff>] reserve_memtype+0xdf/0x2f0 [<c1024dc9>] set_memory_uc+0x49/0xa0 [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa [<c19216d4>] start_kernel+0x291/0x2f2 [<c19211c7>] ? loglevel+0x1b/0x1b [<c19210bf>] 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 <matt.fleming@intel.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Huang Ying <huang.ying.caritas@gmail.com> Cc: Keith Packard <keithp@keithp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1350649546-23541-1-git-send-email-matt@console-pimps.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-10-19 20:25:46 +08:00
u32 type, u64 attribute)
{
unsigned long last_map_pfn;
if (type == EFI_MEMORY_MAPPED_IO)
return ioremap(phys_addr, 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;
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: [<c10257b9>] 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:[<c10257b9>] 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: [<c104f8ca>] ? page_is_ram+0x1a/0x40 [<c1025aff>] reserve_memtype+0xdf/0x2f0 [<c1024dc9>] set_memory_uc+0x49/0xa0 [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa [<c19216d4>] start_kernel+0x291/0x2f2 [<c19211c7>] ? loglevel+0x1b/0x1b [<c19210bf>] 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 <matt.fleming@intel.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Huang Ying <huang.ying.caritas@gmail.com> Cc: Keith Packard <keithp@keithp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1350649546-23541-1-git-send-email-matt@console-pimps.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-10-19 20:25:46 +08:00
efi_ioremap(top, size - (top - phys_addr), type, attribute);
}
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: [<c10257b9>] 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:[<c10257b9>] 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: [<c104f8ca>] ? page_is_ram+0x1a/0x40 [<c1025aff>] reserve_memtype+0xdf/0x2f0 [<c1024dc9>] set_memory_uc+0x49/0xa0 [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa [<c19216d4>] start_kernel+0x291/0x2f2 [<c19211c7>] ? loglevel+0x1b/0x1b [<c19210bf>] 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 <matt.fleming@intel.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Huang Ying <huang.ying.caritas@gmail.com> Cc: Keith Packard <keithp@keithp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1350649546-23541-1-git-send-email-matt@console-pimps.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-10-19 20:25:46 +08:00
if (!(attribute & EFI_MEMORY_WB))
efi_memory_uc((u64)(unsigned long)__va(phys_addr), size);
return (void __iomem *)__va(phys_addr);
}