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Merge branch 'x86-efi-kexec-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI changes from Ingo Molnar: "This consists of two main parts: - New static EFI runtime services virtual mapping layout which is groundwork for kexec support on EFI (Borislav Petkov) - EFI kexec support itself (Dave Young)" * 'x86-efi-kexec-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/efi: parse_efi_setup() build fix x86: ksysfs.c build fix x86/efi: Delete superfluous global variables x86: Reserve setup_data ranges late after parsing memmap cmdline x86: Export x86 boot_params to sysfs x86: Add xloadflags bit for EFI runtime support on kexec x86/efi: Pass necessary EFI data for kexec via setup_data efi: Export EFI runtime memory mapping to sysfs efi: Export more EFI table variables to sysfs x86/efi: Cleanup efi_enter_virtual_mode() function x86/efi: Fix off-by-one bug in EFI Boot Services reservation x86/efi: Add a wrapper function efi_map_region_fixed() x86/efi: Remove unused variables in __map_region() x86/efi: Check krealloc return value x86/efi: Runtime services virtual mapping x86/mm/cpa: Map in an arbitrary pgd x86/mm/pageattr: Add last levels of error path x86/mm/pageattr: Add a PUD error unwinding path x86/mm/pageattr: Add a PTE pagetable populating function x86/mm/pageattr: Add a PMD pagetable populating function ...
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‎Documentation/ABI/testing/sysfs-firmware-efi

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What: /sys/firmware/efi/fw_vendor
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Date: December 2013
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Contact: Dave Young <dyoung@redhat.com>
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Description: It shows the physical address of firmware vendor field in the
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EFI system table.
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Users: Kexec
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What: /sys/firmware/efi/runtime
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Date: December 2013
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Contact: Dave Young <dyoung@redhat.com>
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Description: It shows the physical address of runtime service table entry in
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the EFI system table.
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Users: Kexec
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What: /sys/firmware/efi/config_table
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Date: December 2013
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Contact: Dave Young <dyoung@redhat.com>
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Description: It shows the physical address of config table entry in the EFI
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system table.
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Users: Kexec

‎Documentation/ABI/testing/sysfs-firmware-efi-runtime-map

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What: /sys/firmware/efi/runtime-map/
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Date: December 2013
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Contact: Dave Young <dyoung@redhat.com>
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Description: Switching efi runtime services to virtual mode requires
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that all efi memory ranges which have the runtime attribute
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bit set to be mapped to virtual addresses.
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The efi runtime services can only be switched to virtual
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mode once without rebooting. The kexec kernel must maintain
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the same physical to virtual address mappings as the first
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kernel. The mappings are exported to sysfs so userspace tools
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can reassemble them and pass them into the kexec kernel.
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/sys/firmware/efi/runtime-map/ is the directory the kernel
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exports that information in.
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subdirectories are named with the number of the memory range:
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/sys/firmware/efi/runtime-map/0
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/sys/firmware/efi/runtime-map/1
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/sys/firmware/efi/runtime-map/2
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/sys/firmware/efi/runtime-map/3
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...
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Each subdirectory contains five files:
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attribute : The attributes of the memory range.
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num_pages : The size of the memory range in pages.
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phys_addr : The physical address of the memory range.
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type : The type of the memory range.
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virt_addr : The virtual address of the memory range.
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Above values are all hexadecimal numbers with the '0x' prefix.
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Users: Kexec

‎Documentation/ABI/testing/sysfs-kernel-boot_params

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What: /sys/kernel/boot_params
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Date: December 2013
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Contact: Dave Young <dyoung@redhat.com>
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Description: The /sys/kernel/boot_params directory contains two
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files: "data" and "version" and one subdirectory "setup_data".
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It is used to export the kernel boot parameters of an x86
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platform to userspace for kexec and debugging purpose.
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If there's no setup_data in boot_params the subdirectory will
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not be created.
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"data" file is the binary representation of struct boot_params.
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"version" file is the string representation of boot
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protocol version.
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"setup_data" subdirectory contains the setup_data data
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structure in boot_params. setup_data is maintained in kernel
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as a link list. In "setup_data" subdirectory there's one
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subdirectory for each link list node named with the number
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of the list nodes. The list node subdirectory contains two
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files "type" and "data". "type" file is the string
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representation of setup_data type. "data" file is the binary
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representation of setup_data payload.
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The whole boot_params directory structure is like below:
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/sys/kernel/boot_params
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|__ data
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|__ setup_data
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| |__ 0
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| | |__ data
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| | |__ type
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| |__ 1
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| |__ data
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| |__ type
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|__ version
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Users: Kexec

‎Documentation/kernel-parameters.txt

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@@ -899,6 +899,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
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edd= [EDD]
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Format: {"off" | "on" | "skip[mbr]"}
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efi= [EFI]
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Format: { "old_map" }
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old_map [X86-64]: switch to the old ioremap-based EFI
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runtime services mapping. 32-bit still uses this one by
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default.
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efi_no_storage_paranoia [EFI; X86]
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Using this parameter you can use more than 50% of
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your efi variable storage. Use this parameter only if

‎Documentation/x86/boot.txt

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@@ -608,6 +608,9 @@ Protocol: 2.12+
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- If 1, the kernel supports the 64-bit EFI handoff entry point
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given at handover_offset + 0x200.
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Bit 4 (read): XLF_EFI_KEXEC
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- If 1, the kernel supports kexec EFI boot with EFI runtime support.
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Field name: cmdline_size
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Type: read
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Offset/size: 0x238/4

‎Documentation/x86/x86_64/mm.txt

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@@ -28,4 +28,11 @@ reference.
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Current X86-64 implementations only support 40 bits of address space,
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but we support up to 46 bits. This expands into MBZ space in the page tables.
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->trampoline_pgd:
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We map EFI runtime services in the aforementioned PGD in the virtual
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range of 64Gb (arbitrarily set, can be raised if needed)
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0xffffffef00000000 - 0xffffffff00000000
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-Andi Kleen, Jul 2004

‎arch/x86/boot/header.S

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@@ -391,7 +391,14 @@ xloadflags:
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#else
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# define XLF23 0
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#endif
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.word XLF0 | XLF1 | XLF23
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#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC)
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# define XLF4 XLF_EFI_KEXEC
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#else
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# define XLF4 0
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#endif
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.word XLF0 | XLF1 | XLF23 | XLF4
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cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line,
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#added with boot protocol

‎arch/x86/include/asm/efi.h

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@@ -1,6 +1,24 @@
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#ifndef _ASM_X86_EFI_H
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#define _ASM_X86_EFI_H
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/*
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* We map the EFI regions needed for runtime services non-contiguously,
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* with preserved alignment on virtual addresses starting from -4G down
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* for a total max space of 64G. This way, we provide for stable runtime
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* services addresses across kernels so that a kexec'd kernel can still
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* use them.
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*
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* This is the main reason why we're doing stable VA mappings for RT
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* services.
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*
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* This flag is used in conjuction with a chicken bit called
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* "efi=old_map" which can be used as a fallback to the old runtime
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* services mapping method in case there's some b0rkage with a
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* particular EFI implementation (haha, it is hard to hold up the
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* sarcasm here...).
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*/
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#define EFI_OLD_MEMMAP EFI_ARCH_1
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#ifdef CONFIG_X86_32
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#define EFI_LOADER_SIGNATURE "EL32"
@@ -69,24 +87,31 @@ extern u64 efi_call6(void *fp, u64 arg1, u64 arg2, u64 arg3,
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efi_call6((f), (u64)(a1), (u64)(a2), (u64)(a3), \
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(u64)(a4), (u64)(a5), (u64)(a6))
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#define _efi_call_virtX(x, f, ...) \
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({ \
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efi_status_t __s; \
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\
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efi_sync_low_kernel_mappings(); \
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preempt_disable(); \
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__s = efi_call##x((void *)efi.systab->runtime->f, __VA_ARGS__); \
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preempt_enable(); \
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__s; \
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})
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#define efi_call_virt0(f) \
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efi_call0((efi.systab->runtime->f))
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#define efi_call_virt1(f, a1) \
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efi_call1((efi.systab->runtime->f), (u64)(a1))
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#define efi_call_virt2(f, a1, a2) \
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efi_call2((efi.systab->runtime->f), (u64)(a1), (u64)(a2))
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#define efi_call_virt3(f, a1, a2, a3) \
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efi_call3((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
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(u64)(a3))
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#define efi_call_virt4(f, a1, a2, a3, a4) \
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efi_call4((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
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(u64)(a3), (u64)(a4))
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#define efi_call_virt5(f, a1, a2, a3, a4, a5) \
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efi_call5((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
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(u64)(a3), (u64)(a4), (u64)(a5))
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#define efi_call_virt6(f, a1, a2, a3, a4, a5, a6) \
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efi_call6((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
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(u64)(a3), (u64)(a4), (u64)(a5), (u64)(a6))
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_efi_call_virtX(0, f)
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#define efi_call_virt1(f, a1) \
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_efi_call_virtX(1, f, (u64)(a1))
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#define efi_call_virt2(f, a1, a2) \
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_efi_call_virtX(2, f, (u64)(a1), (u64)(a2))
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#define efi_call_virt3(f, a1, a2, a3) \
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_efi_call_virtX(3, f, (u64)(a1), (u64)(a2), (u64)(a3))
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#define efi_call_virt4(f, a1, a2, a3, a4) \
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_efi_call_virtX(4, f, (u64)(a1), (u64)(a2), (u64)(a3), (u64)(a4))
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#define efi_call_virt5(f, a1, a2, a3, a4, a5) \
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_efi_call_virtX(5, f, (u64)(a1), (u64)(a2), (u64)(a3), (u64)(a4), (u64)(a5))
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#define efi_call_virt6(f, a1, a2, a3, a4, a5, a6) \
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_efi_call_virtX(6, f, (u64)(a1), (u64)(a2), (u64)(a3), (u64)(a4), (u64)(a5), (u64)(a6))
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extern void __iomem *efi_ioremap(unsigned long addr, unsigned long size,
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u32 type, u64 attribute);
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96121
extern int add_efi_memmap;
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extern unsigned long x86_efi_facility;
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extern struct efi_scratch efi_scratch;
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extern void efi_set_executable(efi_memory_desc_t *md, bool executable);
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extern int efi_memblock_x86_reserve_range(void);
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extern void efi_call_phys_prelog(void);
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extern void efi_call_phys_epilog(void);
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extern void efi_unmap_memmap(void);
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extern void efi_memory_uc(u64 addr, unsigned long size);
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extern void __init efi_map_region(efi_memory_desc_t *md);
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extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
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extern void efi_sync_low_kernel_mappings(void);
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extern void efi_setup_page_tables(void);
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extern void __init old_map_region(efi_memory_desc_t *md);
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136+
struct efi_setup_data {
137+
u64 fw_vendor;
138+
u64 runtime;
139+
u64 tables;
140+
u64 smbios;
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u64 reserved[8];
142+
};
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144+
extern u64 efi_setup;
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105146
#ifdef CONFIG_EFI
106147

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110151
}
111152

112153
extern struct console early_efi_console;
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154+
extern void parse_efi_setup(u64 phys_addr, u32 data_len);
114155
#else
115156
/*
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* IF EFI is not configured, have the EFI calls return -ENOSYS.
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#define efi_call4(_f, _a1, _a2, _a3, _a4) (-ENOSYS)
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#define efi_call5(_f, _a1, _a2, _a3, _a4, _a5) (-ENOSYS)
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#define efi_call6(_f, _a1, _a2, _a3, _a4, _a5, _a6) (-ENOSYS)
166+
static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
125167
#endif /* CONFIG_EFI */
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#endif /* _ASM_X86_EFI_H */

‎arch/x86/include/asm/pgtable_types.h

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@@ -382,7 +382,8 @@ static inline void update_page_count(int level, unsigned long pages) { }
382382
*/
383383
extern pte_t *lookup_address(unsigned long address, unsigned int *level);
384384
extern phys_addr_t slow_virt_to_phys(void *__address);
385-
385+
extern int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
386+
unsigned numpages, unsigned long page_flags);
386387
#endif /* !__ASSEMBLY__ */
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388389
#endif /* _ASM_X86_PGTABLE_DEFS_H */

‎arch/x86/include/uapi/asm/bootparam.h

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@@ -6,6 +6,7 @@
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#define SETUP_E820_EXT 1
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#define SETUP_DTB 2
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#define SETUP_PCI 3
9+
#define SETUP_EFI 4
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1011
/* ram_size flags */
1112
#define RAMDISK_IMAGE_START_MASK 0x07FF
@@ -23,6 +24,7 @@
2324
#define XLF_CAN_BE_LOADED_ABOVE_4G (1<<1)
2425
#define XLF_EFI_HANDOVER_32 (1<<2)
2526
#define XLF_EFI_HANDOVER_64 (1<<3)
27+
#define XLF_EFI_KEXEC (1<<4)
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#ifndef __ASSEMBLY__
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‎arch/x86/kernel/Makefile

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@@ -29,6 +29,7 @@ obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o
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obj-y += syscall_$(BITS).o
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obj-$(CONFIG_X86_64) += vsyscall_64.o
3131
obj-$(CONFIG_X86_64) += vsyscall_emu_64.o
32+
obj-$(CONFIG_SYSFS) += ksysfs.o
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obj-y += bootflag.o e820.o
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obj-y += pci-dma.o quirks.o topology.o kdebugfs.o
3435
obj-y += alternative.o i8253.o pci-nommu.o hw_breakpoint.o

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