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2016-05-25Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: EFI, entry code, pkeys and MPX fixes, TASK_SIZE cleanups and a tsc frequency table fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Switch from TASK_SIZE to TASK_SIZE_MAX in the page fault code x86/fsgsbase/64: Use TASK_SIZE_MAX for FSBASE/GSBASE upper limits x86/mm/mpx: Work around MPX erratum SKD046 x86/entry/64: Fix stack return address retrieval in thunk x86/efi: Fix 7-parameter efi_call()s x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys x86/tsc: Add missing Cherrytrail frequency to the table
2016-05-20Merge branch 'linus' into x86/urgent, to refresh the treeIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-17x86/efi: Fix 7-parameter efi_call()sLinus Torvalds
Alex Thorlton reported that the SGI/UV code crashes in the efi_call() code when invoked with 7 parameters, due to: mov (%rsp), %rax mov 8(%rax), %rax ... mov %rax, 40(%rsp) Offset 8 is only true if CONFIG_FRAME_POINTERS is disabled, with frame pointers enabled it should be 16. Furthermore, the SAVE_XMM code saves the old stack pointer, but that's just crazy. It saves the stack pointer *AFTER* we've done the: FRAME_BEGIN ... which will have *changed* the stack pointer, depending on whether stack frames are enabled or not. So when the code then does: mov (%rsp), %rax ... we now move that old stack pointer into %rax, but the offset off that stack pointer will depend on whether that FRAME_BEGIN saved off %rbp or not. So that whole 8-vs-16 offset confusion depends on the frame pointer! If frame pointers were enabled, it will be 16. If they weren't, it will be 8. The right fix is to just get rid of that silly conditional frame pointer thing, and always use frame pointers in this stub function. And then we don't need that (odd) load to get the old stack pointer into %rax - we can just use the frame pointer. Reported-by: Alex Thorlton <athorlton@sgi.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/CA%2B55aFzBS2v%3DWnEH83cUDg7XkOremFqJ30BJwF40dCYjReBkUQ@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-16Merge tag 'acpi-4.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "The new features here are ACPI 6.1 support (and some previously missing bits of ACPI 6.0 support) in ACPICA and two new drivers, a driver for the ACPI Generic Event Device (GED) feature introduced by ACPI 6.1 and the INT3406 thermal driver for display thermal management. Also the value returned by the _HRV (hardware revision) ACPI object will be exported to user space via sysfs now. In addition to that, ACPI on ARM64 will not depend on EXPERT any more. The rest is mostly fixes and cleanups and some code reorganization. Specifics: - In-kernel ACPICA code update to the upstream release 20160422 adding support for ACPI 6.1 along with some previously missing bits of ACPI 6.0 support, making a fair amount of fixes and cleanups and reducing divergences between the upstream ACPICA and the in-kernel code (Bob Moore, Lv Zheng, Al Stone, Aleksey Makarov, Will Miles) - ACPI Generic Event Device (GED) support and a fix for it (Sinan Kaya, Paul Gortmaker) - INT3406 thermal driver for display thermal management and ACPI backlight support code reorganization related to it (Aaron Lu, Arnd Bergmann) - Support for exporting the value returned by the _HRV (hardware revision) ACPI object via sysfs (Betty Dall) - Removal of the EXPERT dependency for ACPI on ARM64 (Mark Brown) - Rework of the handling of ACPI _OSI mechanism allowing the _OSI("Darwin") support to be overridden from the kernel command line among other things (Lv Zheng, Chen Yu) - Rework of the ACPI tables override mechanism to prepare it for the introduction of overlays support going forward (Lv Zheng, Rafael Wysocki) - Fixes related to the ECDT support and module-level execution of AML (Lv Zheng) - ACPI PCI interrupts management update to make it work better on ARM64 mostly (Sinan Kaya) - ACPI SRAT handling update to make the code process all entires in the table order regardless of the entry type (Lukasz Anaczkowski) - EFI power off support for full-hardware ACPI platforms that don't support ACPI S5 (Chen Yu) - Fixes and cleanups related to the ACPI core's sysfs interface (Dan Carpenter, Betty Dall) - acpi_dev_present() API rework to reduce possible confusion related to it (Lukas Wunner) - Removal of CLK_IS_ROOT from two ACPI drivers (Stephen Boyd)" * tag 'acpi-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (82 commits) ACPI / video: mark acpi_video_get_levels() inline Thermal / ACPI / video: add INT3406 thermal driver ACPI / GED: make evged.c explicitly non-modular ACPI / tables: Fix DSDT override mechanism ACPI / sysfs: fix error code in get_status() ACPICA: Update version to 20160422 ACPICA: Move all ASCII utilities to a common file ACPICA: ACPI 2.0, Hardware: Add access_width/bit_offset support for acpi_hw_write() ACPICA: ACPI 2.0, Hardware: Add access_width/bit_offset support in acpi_hw_read() ACPICA: Executer: Introduce a set of macros to handle bit width mask generation ACPICA: Hardware: Add optimized access bit width support ACPICA: Utilities: Add ACPI_IS_ALIGNED() macro ACPICA: Renamed some #defined flag constants for clarity ACPICA: ACPI 6.0, tools/iasl: Add support for new resource descriptors ACPICA: ACPI 6.0: Update _BIX support for new package element ACPICA: ACPI 6.1: Support for new PCCT subtable ACPICA: Refactor evaluate_object to reduce nesting ACPICA: Divergence: remove unwanted spaces for typedef ACPI,PCI,IRQ: remove SCI penalize function ACPI,PCI,IRQ: remove redundant code in acpi_irq_penalty_init() ..
2016-05-16Merge branches 'acpi-drivers', 'acpi-pm', 'acpi-ec' and 'acpi-video'Rafael J. Wysocki
* acpi-drivers: ACPI / GED: make evged.c explicitly non-modular ACPI / amba: Remove CLK_IS_ROOT ACPI / APD: Remove CLK_IS_ROOT ACPI: implement Generic Event Device * acpi-pm: ACPI / PM: Introduce efi poweroff for HW-full platforms without _S5 * acpi-ec: ACPI 2.0 / AML: Improve module level execution by moving the If/Else/While execution to per-table basis ACPI 2.0 / ECDT: Enable correct ECDT initialization order ACPI 2.0 / ECDT: Remove early namespace reference from EC ACPI 2.0 / ECDT: Split EC_FLAGS_HANDLERS_INSTALLED * acpi-video: ACPI / video: mark acpi_video_get_levels() inline Thermal / ACPI / video: add INT3406 thermal driver ACPI/video: export acpi_video_get_levels video / backlight: remove the backlight_device_registered API video / backlight: add two APIs for drivers to use
2016-05-07Merge branch 'linus' into efi/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-04x86/efi-bgrt: Switch all pr_err() to pr_notice() for invalid BGRTJosh Boyer
The promise of pretty boot splashes from firmware via BGRT was at best only that; a promise. The kernel diligently checks to make sure the BGRT data firmware gives it is valid, and dutifully warns the user when it isn't. However, it does so via the pr_err log level which seems unnecessary. The user cannot do anything about this and there really isn't an error on the part of Linux to correct. This lowers the log level by using pr_notice instead. Users will no longer have their boot process uglified by the kernel reminding us that firmware can and often is broken when the 'quiet' kernel parameter is specified. Ironic, considering BGRT is supposed to make boot pretty to begin with. Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Môshe van der Sterre <me@moshe.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1462303781-8686-4-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28x86/efi: Remove the always true EFI_DEBUG symbolMatt Fleming
This symbol is always set which makes it useless. Additionally we have a kernel command-line switch, efi=debug, which actually controls the printing of the memory map. Reported-by: Robert Elliott <elliott@hpe.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Borislav Petkov <bp@suse.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-16-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Check EFI_MEMORY_DESCRIPTOR version explicitlyArd Biesheuvel
Our efi_memory_desc_t type is based on EFI_MEMORY_DESCRIPTOR version 1 in the UEFI spec. No version updates are expected, but since we are about to introduce support for new firmware tables that use the same descriptor type, it makes sense to at least warn if we encounter other versions. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-9-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Remove global 'memmap' EFI memory mapMatt Fleming
Abolish the poorly named EFI memory map, 'memmap'. It is shadowed by a bunch of local definitions in various files and having two ways to access the EFI memory map ('efi.memmap' vs. 'memmap') is rather confusing. Furthermore, IA64 doesn't even provide this global object, which has caused issues when trying to write generic EFI memmap code. Replace all occurrences with efi.memmap, and convert the remaining iterator code to use for_each_efi_mem_desc(). Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Luck, Tony <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-8-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Iterate over efi.memmap in for_each_efi_memory_desc()Matt Fleming
Most of the users of for_each_efi_memory_desc() are equally happy iterating over the EFI memory map in efi.memmap instead of 'memmap', since the former is usually a pointer to the latter. For those users that want to specify an EFI memory map other than efi.memmap, that can be done using for_each_efi_memory_desc_in_map(). One such example is in the libstub code where the firmware is queried directly for the memory map, it gets iterated over, and then freed. This change goes part of the way toward deleting the global 'memmap' variable, which is not universally available on all architectures (notably IA64) and is rather poorly named. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-7-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Get rid of the EFI_SYSTEM_TABLES status bitArd Biesheuvel
The EFI_SYSTEM_TABLES status bit is set by all EFI supporting architectures upon discovery of the EFI system table, but the bit is never tested in any code we have in the tree. So remove it. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Luck, Tony <tony.luck@intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-09ACPI / PM: Introduce efi poweroff for HW-full platforms without _S5Chen Yu
The problem is Linux registers pm_power_off = efi_power_off only if we are in hardware reduced mode. Actually, what we also want is to do this when ACPI S5 is simply not supported on non-legacy platforms. Since some future Intel platforms are HW-full mode where the DSDT fails to supply an _S5 object(without SLP_TYP), we should let such kind of platform to leverage efi runtime service to poweroff. This patch uses efi power off as first choice when S5 is unavailable, even if there is a customized poweroff(driver provided, eg). Meanwhile, the legacy platforms will not be affected because there is no path for them to overwrite the pm_power_off to efi power off. Suggested-by: Len Brown <len.brown@intel.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-20Merge branch 'efi-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Ingo Molnar: "The main changes are: - Use separate EFI page tables when executing EFI firmware code. This isolates the EFI context from the rest of the kernel, which has security and general robustness advantages. (Matt Fleming) - Run regular UEFI firmware with interrupts enabled. This is already the status quo under other OSs. (Ard Biesheuvel) - Various x86 EFI enhancements, such as the use of non-executable attributes for EFI memory mappings. (Sai Praneeth Prakhya) - Various arm64 UEFI enhancements. (Ard Biesheuvel) - ... various fixes and cleanups. The separate EFI page tables feature got delayed twice already, because it's an intrusive change and we didn't feel confident about it - third time's the charm we hope!" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) x86/mm/pat: Fix boot crash when 1GB pages are not supported by the CPU x86/efi: Only map kernel text for EFI mixed mode x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd() efi/arm*: Perform hardware compatibility check efi/arm64: Check for h/w support before booting a >4 KB granular kernel efi/arm: Check for LPAE support before booting a LPAE kernel efi/arm-init: Use read-only early mappings efi/efistub: Prevent __init annotations from being used arm64/vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections efi/arm64: Drop __init annotation from handle_kernel_image() x86/mm/pat: Use _PAGE_GLOBAL bit for EFI page table mappings efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled efi: Reformat GUID tables to follow the format in UEFI spec efi: Add Persistent Memory type name efi: Add NV memory attribute x86/efi: Show actual ending addresses in efi_print_memmap x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0 efivars: Use to_efivar_entry efi: Runtime-wrapper: Get rid of the rtc_lock spinlock ...
2016-03-20Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull 'objtool' stack frame validation from Ingo Molnar: "This tree adds a new kernel build-time object file validation feature (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation. It was written by and is maintained by Josh Poimboeuf. The motivation: there's a category of hard to find kernel bugs, most of them in assembly code (but also occasionally in C code), that degrades the quality of kernel stack dumps/backtraces. These bugs are hard to detect at the source code level. Such bugs result in incorrect/incomplete backtraces most of time - but can also in some rare cases result in crashes or other undefined behavior. The build time correctness checking is done via the new 'objtool' user-space utility that was written for this purpose and which is hosted in the kernel repository in tools/objtool/. The tool's (very simple) UI and source code design is shaped after Git and perf and shares quite a bit of infrastructure with tools/perf (which tooling infrastructure sharing effort got merged via perf and is already upstream). Objtool follows the well-known kernel coding style. Objtool does not try to check .c or .S files, it instead analyzes the resulting .o generated machine code from first principles: it decodes the instruction stream and interprets it. (Right now objtool supports the x86-64 architecture.) From tools/objtool/Documentation/stack-validation.txt: "The kernel CONFIG_STACK_VALIDATION option enables a host tool named objtool which runs at compile time. It has a "check" subcommand which analyzes every .o file and ensures the validity of its stack metadata. It enforces a set of rules on asm code and C inline assembly code so that stack traces can be reliable. Currently it only checks frame pointer usage, but there are plans to add CFI validation for C files and CFI generation for asm files. For each function, it recursively follows all possible code paths and validates the correct frame pointer state at each instruction. It also follows code paths involving special sections, like .altinstructions, __jump_table, and __ex_table, which can add alternative execution paths to a given instruction (or set of instructions). Similarly, it knows how to follow switch statements, for which gcc sometimes uses jump tables." When this new kernel option is enabled (it's disabled by default), the tool, if it finds any suspicious assembly code pattern, outputs warnings in compiler warning format: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup warning: objtool:__schedule()+0x3c0: duplicate frame pointer save warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer ... so that scripts that pick up compiler warnings will notice them. All known warnings triggered by the tool are fixed by the tree, most of the commits in fact prepare the kernel to be warning-free. Most of them are bugfixes or cleanups that stand on their own, but there are also some annotations of 'special' stack frames for justified cases such entries to JIT-ed code (BPF) or really special boot time code. There are two other long-term motivations behind this tool as well: - To improve the quality and reliability of kernel stack frames, so that they can be used for optimized live patching. - To create independent infrastructure to check the correctness of CFI stack frames at build time. CFI debuginfo is notoriously unreliable and we cannot use it in the kernel as-is without extra checking done both on the kernel side and on the build side. The quality of kernel stack frames matters to debuggability as well, so IMO we can merge this without having to consider the live patching or CFI debuginfo angle" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) objtool: Only print one warning per function objtool: Add several performance improvements tools: Copy hashtable.h into tools directory objtool: Fix false positive warnings for functions with multiple switch statements objtool: Rename some variables and functions objtool: Remove superflous INIT_LIST_HEAD objtool: Add helper macros for traversing instructions objtool: Fix false positive warnings related to sibling calls objtool: Compile with debugging symbols objtool: Detect infinite recursion objtool: Prevent infinite recursion in noreturn detection objtool: Detect and warn if libelf is missing and don't break the build tools: Support relative directory path for 'O=' objtool: Support CROSS_COMPILE x86/asm/decoder: Use explicitly signed chars objtool: Enable stack metadata validation on 64-bit x86 objtool: Add CONFIG_STACK_VALIDATION option objtool: Add tool to perform compile-time stack metadata validation x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard sched: Always inline context_switch() ...
2016-03-12x86/efi: Fix boot crash by always mapping boot service regions into new EFI ↵Matt Fleming
page tables Some machines have EFI regions in page zero (physical address 0x00000000) and historically that region has been added to the e820 map via trim_bios_range(), and ultimately mapped into the kernel page tables. It was not mapped via efi_map_regions() as one would expect. Alexis reports that with the new separate EFI page tables some boot services regions, such as page zero, are not mapped. This triggers an oops during the SetVirtualAddressMap() runtime call. For the EFI boot services quirk on x86 we need to memblock_reserve() boot services regions until after SetVirtualAddressMap(). Doing that while respecting the ownership of regions that may have already been reserved by the kernel was the motivation behind this commit: 7d68dc3f1003 ("x86, efi: Do not reserve boot services regions within reserved areas") That patch was merged at a time when the EFI runtime virtual mappings were inserted into the kernel page tables as described above, and the trick of setting ->numpages (and hence the region size) to zero to track regions that should not be freed in efi_free_boot_services() meant that we never mapped those regions in efi_map_regions(). Instead we were relying solely on the existing kernel mappings. Now that we have separate page tables we need to make sure the EFI boot services regions are mapped correctly, even if someone else has already called memblock_reserve(). Instead of stashing a tag in ->numpages, set the EFI_MEMORY_RUNTIME bit of ->attribute. Since it generally makes no sense to mark a boot services region as required at runtime, it's pretty much guaranteed the firmware will not have already set this bit. For the record, the specific circumstances under which Alexis triggered this bug was that an EFI runtime driver on his machine was responding to the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event during SetVirtualAddressMap(). The event handler for this driver looks like this, sub rsp,0x28 lea rdx,[rip+0x2445] # 0xaa948720 mov ecx,0x4 call func_aa9447c0 ; call to ConvertPointer(4, & 0xaa948720) mov r11,QWORD PTR [rip+0x2434] # 0xaa948720 xor eax,eax mov BYTE PTR [r11+0x1],0x1 add rsp,0x28 ret Which is pretty typical code for an EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE handler. The "mov r11, QWORD PTR [rip+0x2424]" was the faulting instruction because ConvertPointer() was being called to convert the address 0x0000000000000000, which when converted is left unchanged and remains 0x0000000000000000. The output of the oops trace gave the impression of a standard NULL pointer dereference bug, but because we're accessing physical addresses during ConvertPointer(), it wasn't. EFI boot services code is stored at that address on Alexis' machine. Reported-by: Alexis Murzeau <amurzeau@gmail.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Raphael Hertzog <hertzog@debian.org> Cc: Roger Shimizu <rogershimizu@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1457695163-29632-2-git-send-email-matt@codeblueprint.co.uk Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=815125 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29objtool: Mark non-standard object files and directoriesJosh Poimboeuf
Code which runs outside the kernel's normal mode of operation often does unusual things which can cause a static analysis tool like objtool to emit false positive warnings: - boot image - vdso image - relocation - realmode - efi - head - purgatory - modpost Set OBJECT_FILES_NON_STANDARD for their related files and directories, which will tell objtool to skip checking them. It's ok to skip them because they don't affect runtime stack traces. Also skip the following code which does the right thing with respect to frame pointers, but is too "special" to be validated by a tool: - entry - mcount Also skip the test_nx module because it modifies its exception handling table at runtime, which objtool can't understand. Fortunately it's just a test module so it doesn't matter much. Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it might eventually be useful for other tools. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24x86/asm/efi: Create a stack frame in efi_call()Josh Poimboeuf
efi_call() is a callable non-leaf function which doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Create a stack frame for it when CONFIG_FRAME_POINTER is enabled. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/2294b6fad60eea4cc862eddc8e98a1324e6eeeca.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22x86/efi: Only map kernel text for EFI mixed modeSai Praneeth
The correct symbol to use when figuring out the size of the kernel text is '_etext', not '_end' which is the symbol for the entire kernel image includes data and debug sections. Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-14-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tablesSai Praneeth
Now that we have EFI memory region bits that indicate which regions do not need execute permission or read/write permission in the page tables, let's use them. We also check for EFI_NX_PE_DATA and only enforce the restrictive mappings if it's present (to allow us to ignore buggy firmware that sets bits it didn't mean to and to preserve backwards compatibility). Instead of assuming that firmware would set appropriate attributes in memory descriptor like EFI_MEMORY_RO for code and EFI_MEMORY_XP for data, we can expect some firmware out there which might only set *type* in memory descriptor to be EFI_RUNTIME_SERVICES_CODE or EFI_RUNTIME_SERVICES_DATA leaving away attribute. This will lead to improper mappings of EFI runtime regions. In order to avoid it, we check attribute and type of memory descriptor to update mappings and moreover Windows works this way. Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Lee, Chun-Yi <jlee@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-13-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()Sai Praneeth
As part of the preparation for the EFI_MEMORY_RO flag added in the UEFI 2.5 specification, we need the ability to map pages in kernel page tables without _PAGE_RW being set. Modify kernel_map_pages_in_pgd() to require its callers to pass _PAGE_RW if the pages need to be mapped read/write. Otherwise, we'll map the pages as read-only. Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Lee, Chun-Yi <jlee@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1455712566-16727-12-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03x86/efi: Show actual ending addresses in efi_print_memmapRobert Elliott
Adjust efi_print_memmap to print the real end address of each range, not 1 byte beyond. This matches other prints like those for SRAT and nosave memory. While investigating grub persistent memory corruption issues, it was helpful to make this table match the ending address convention used by: * the kernel's e820 table prints BIOS-e820: [mem 0x0000001680000000-0x0000001c7fffffff] reserved * the kernel's nosave memory prints PM: Registered nosave memory: [mem 0x880000000-0xc7fffffff] * the kernel's ACPI System Resource Affinity Table prints SRAT: Node 1 PXM 1 [mem 0x480000000-0x87fffffff] * grub's lsmmap and lsefimmap commands reserved 0000001680000000-0000001c7fffffff 00600000 24GiB UC WC WT WB NV * the UEFI shell's memmap command Reserved 000000007FC00000-000000007FFFFFFF 0000000000000400 0000000000000001 For example, if you grep all the various logs for c7fffffff, you won't find the kernel's line if it uses c80000000. Also, change the closing ) to ] to match the opening [. old: efi: mem61: [Persistent Memory | | | | | | | |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c80000000) (16384MB) new: efi: mem61: [Persistent Memory | | | | | | | |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff] (16384MB) Signed-off-by: Robert Elliott <elliott@hpe.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1454364428-494-12-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0Môshe van der Sterre
Unintuitively, the BGRT graphic is apparently meant to be usable if the valid bit in not set. The valid bit only conveys uncertainty about the validity in relation to the screen state. Windows 10 actually uses the BGRT image for its boot screen even if not 'valid', for example when the user triggered the boot menu. Because it is unclear if all firmwares will provide a usable graphic in this case, we now look at the BMP magic number as an additional check. Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Môshe van der Sterre <me@moshe.nl> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: =?UTF-8?q?M=C3=B4she=20van=20der=20Sterre?= <me@moshe.nl> Link: http://lkml.kernel.org/r/1454364428-494-10-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03efi: Add nonblocking option to efi_query_variable_store()Ard Biesheuvel
The function efi_query_variable_store() may be invoked by efivar_entry_set_nonblocking(), which itself takes care to only call a non-blocking version of the SetVariable() runtime wrapper. However, efi_query_variable_store() may call the SetVariable() wrapper directly, as well as the wrapper for QueryVariableInfo(), both of which could deadlock in the same way we are trying to prevent by calling efivar_entry_set_nonblocking() in the first place. So instead, modify efi_query_variable_store() to use the non-blocking variants of QueryVariableInfo() (and give up rather than free up space if the available space is below EFI_MIN_RESERVE) if invoked with the 'nonblocking' argument set to true. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1454364428-494-5-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03Merge branch 'linus' into efi/core, to refresh the branch and to pick up ↵Ingo Molnar
recent fixes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-21x86/efi: Setup separate EFI page tables in kexec pathsMatt Fleming
The switch to using a new dedicated page table for EFI runtime calls in commit commit 67a9108ed431 ("x86/efi: Build our own page table structures") failed to take into account changes required for the kexec code paths, which are unfortunately duplicated in the EFI code. Call the allocation and setup functions in kexec_enter_virtual_mode() just like we do for __efi_enter_virtual_mode() to avoid hitting NULL-pointer dereferences when making EFI runtime calls. At the very least, the call to efi_setup_page_tables() should have existed for kexec before the following commit: 67a9108ed431 ("x86/efi: Build our own page table structures") Things just magically worked because we were actually using the kernel's page tables that contained the required mappings. Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453385519-11477-1-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-19x86/platform/UV: Remove EFI memmap quirk for UV2+Alex Thorlton
Commit a5d90c923bcf ("x86/efi: Quirk out SGI UV") added a quirk to efi_apply_memmap_quirks to force SGI UV systems to fall back to the old EFI memmap mechanism. We have a BIOS fix for this issue on all systems except for UV1. This commit fixes up the EFI quirk/MMR mapping code so that we only apply the special case to UV1 hardware. Signed-off-by: Alex Thorlton <athorlton@sgi.com> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hedi Berriche <hedi@sgi.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Travis <travis@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1449867585-189233-2-git-send-email-athorlton@sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-06x86/efi-bgrt: Replace early_memremap() with memremap()Matt Fleming
Môshe reported the following warning triggered on his machine since commit 50a0cb565246 ("x86/efi-bgrt: Fix kernel panic when mapping BGRT data"), [ 0.026936] ------------[ cut here ]------------ [ 0.026941] WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:137 __early_ioremap+0x102/0x1bb() [ 0.026941] Modules linked in: [ 0.026944] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-rc1 #2 [ 0.026945] Hardware name: Dell Inc. XPS 13 9343/09K8G1, BIOS A05 07/14/2015 [ 0.026946] 0000000000000000 900f03d5a116524d ffffffff81c03e60 ffffffff813a3fff [ 0.026948] 0000000000000000 ffffffff81c03e98 ffffffff810a0852 00000000d7b76000 [ 0.026949] 0000000000000000 0000000000000001 0000000000000001 000000000000017c [ 0.026951] Call Trace: [ 0.026955] [<ffffffff813a3fff>] dump_stack+0x44/0x55 [ 0.026958] [<ffffffff810a0852>] warn_slowpath_common+0x82/0xc0 [ 0.026959] [<ffffffff810a099a>] warn_slowpath_null+0x1a/0x20 [ 0.026961] [<ffffffff81d8c395>] __early_ioremap+0x102/0x1bb [ 0.026962] [<ffffffff81d8c602>] early_memremap+0x13/0x15 [ 0.026964] [<ffffffff81d78361>] efi_bgrt_init+0x162/0x1ad [ 0.026966] [<ffffffff81d778ec>] efi_late_init+0x9/0xb [ 0.026968] [<ffffffff81d58ff5>] start_kernel+0x46f/0x49f [ 0.026970] [<ffffffff81d58120>] ? early_idt_handler_array+0x120/0x120 [ 0.026972] [<ffffffff81d58339>] x86_64_start_reservations+0x2a/0x2c [ 0.026974] [<ffffffff81d58485>] x86_64_start_kernel+0x14a/0x16d [ 0.026977] ---[ end trace f9b3812eb8e24c58 ]--- [ 0.026978] efi_bgrt: Ignoring BGRT: failed to map image memory early_memremap() has an upper limit on the size of mapping it can handle which is ~200KB. Clearly the BGRT image on Môshe's machine is much larger than that. There's actually no reason to restrict ourselves to using the early_* version of memremap() - the ACPI BGRT driver is invoked late enough in boot that we can use the standard version, with the benefit that the late version allows mappings of arbitrary size. Reported-by: Môshe van der Sterre <me@moshe.nl> Tested-by: Môshe van der Sterre <me@moshe.nl> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1450707172-12561-1-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19Merge tag 'efi-next' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi Pull efi changes from Matt Fleming: * We don't need to carry our own formatting code in the esrt driver because the kobject API can do that for us - Rasmus Villemoes * Update the arm64 file paths in Documentation/efi-stub.txt to match the current tree - Alan Ott * Consistently preface all print statements with "efi" arch/x86 so that it's more obvious to users reporting problems which statements in the kernel log are relevant for EFI - Matt Fleming * Fix a boot crash in the ACPI BGRT driver and delete efi_lookup_mapped_addr() since it's useless now that the EFI mappings *only* exist in the 'efi_pgd' page table. Instead we always early_memremap() the BGRT memory - Sai Praneeth Prakhya
2015-12-14x86/efi-bgrt: Fix kernel panic when mapping BGRT dataSai Praneeth
Starting with this commit 35eb8b81edd4 ("x86/efi: Build our own page table structures") efi regions have a separate page directory called "efi_pgd". In order to access any efi region we have to first shift %cr3 to this page table. In the bgrt code we are trying to copy bgrt_header and image, but these regions fall under "EFI_BOOT_SERVICES_DATA" and to access these regions we have to shift %cr3 to efi_pgd and not doing so will cause page fault as shown below. [ 0.251599] Last level dTLB entries: 4KB 64, 2MB 0, 4MB 0, 1GB 4 [ 0.259126] Freeing SMP alternatives memory: 32K (ffffffff8230e000 - ffffffff82316000) [ 0.271803] BUG: unable to handle kernel paging request at fffffffefce35002 [ 0.279740] IP: [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd [ 0.286383] PGD 300f067 PUD 0 [ 0.289879] Oops: 0000 [#1] SMP [ 0.293566] Modules linked in: [ 0.297039] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-rc1-eywa-eywa-built-in-47041+ #2 [ 0.306619] Hardware name: Intel Corporation Skylake Client platform/Skylake Y LPDDR3 RVP3, BIOS SKLSE2R1.R00.B104.B01.1511110114 11/11/2015 [ 0.320925] task: ffffffff820134c0 ti: ffffffff82000000 task.ti: ffffffff82000000 [ 0.329420] RIP: 0010:[<ffffffff821bca49>] [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd [ 0.338821] RSP: 0000:ffffffff82003f18 EFLAGS: 00010246 [ 0.344852] RAX: fffffffefce35000 RBX: fffffffefce35000 RCX: fffffffefce2b000 [ 0.352952] RDX: 000000008a82b000 RSI: ffffffff8235bb80 RDI: 000000008a835000 [ 0.361050] RBP: ffffffff82003f30 R08: 000000008a865000 R09: ffffffffff202850 [ 0.369149] R10: ffffffff811ad62f R11: 0000000000000000 R12: 0000000000000000 [ 0.377248] R13: ffff88016dbaea40 R14: ffffffff822622c0 R15: ffffffff82003fb0 [ 0.385348] FS: 0000000000000000(0000) GS:ffff88016d800000(0000) knlGS:0000000000000000 [ 0.394533] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 0.401054] CR2: fffffffefce35002 CR3: 000000000300c000 CR4: 00000000003406f0 [ 0.409153] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 0.417252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 0.425350] Stack: [ 0.427638] ffffffffffffffff ffffffff82256900 ffff88016dbaea40 ffffffff82003f40 [ 0.436086] ffffffff821bbce0 ffffffff82003f88 ffffffff8219c0c2 0000000000000000 [ 0.444533] ffffffff8219ba4a ffffffff822622c0 0000000000083000 00000000ffffffff [ 0.452978] Call Trace: [ 0.455763] [<ffffffff821bbce0>] efi_late_init+0x9/0xb [ 0.461697] [<ffffffff8219c0c2>] start_kernel+0x463/0x47f [ 0.467928] [<ffffffff8219ba4a>] ? set_init_arg+0x55/0x55 [ 0.474159] [<ffffffff8219b120>] ? early_idt_handler_array+0x120/0x120 [ 0.481669] [<ffffffff8219b5ee>] x86_64_start_reservations+0x2a/0x2c [ 0.488982] [<ffffffff8219b72d>] x86_64_start_kernel+0x13d/0x14c [ 0.495897] Code: 00 41 b4 01 48 8b 78 28 e8 09 36 01 00 48 85 c0 48 89 c3 75 13 48 c7 c7 f8 ac d3 81 31 c0 e8 d7 3b fb fe e9 b5 00 00 00 45 84 e4 <44> 8b 6b 02 74 0d be 06 00 00 00 48 89 df e8 ae 34 0$ [ 0.518151] RIP [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd [ 0.524888] RSP <ffffffff82003f18> [ 0.528851] CR2: fffffffefce35002 [ 0.532615] ---[ end trace 7b06521e6ebf2aea ]--- [ 0.537852] Kernel panic - not syncing: Attempted to kill the idle task! As said above one way to fix this bug is to shift %cr3 to efi_pgd but we are not doing that way because it leaks inner details of how we switch to EFI page tables into a new call site and it also adds duplicate code. Instead, we remove the call to efi_lookup_mapped_addr() and always perform early_mem*() instead of early_io*() because we want to remap RAM regions and not I/O regions. We also delete efi_lookup_mapped_addr() because we are no longer using it. Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Reported-by: Wendy Wang <wendy.wang@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2015-12-14x86/efi: Preface all print statements with efi* tagMatt Fleming
The pr_*() calls in the x86 EFI code may or may not include a subsystem tag, which makes it difficult to grep the kernel log for all relevant EFI messages and leads users to miss important information. Recently, a bug reporter provided all the EFI print messages from the kernel log when trying to diagnose an issue but missed the following statement because it wasn't prefixed with anything indicating it was related to EFI, pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap); Cc: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2015-11-29x86/efi: Build our own page table structuresMatt Fleming
With commit e1a58320a38d ("x86/mm: Warn on W^X mappings") all users booting on 64-bit UEFI machines see the following warning, ------------[ cut here ]------------ WARNING: CPU: 7 PID: 1 at arch/x86/mm/dump_pagetables.c:225 note_page+0x5dc/0x780() x86/mm: Found insecure W+X mapping at address ffff88000005f000/0xffff88000005f000 ... x86/mm: Checked W+X mappings: FAILED, 165660 W+X pages found. ... This is caused by mapping EFI regions with RWX permissions. There isn't much we can do to restrict the permissions for these regions due to the way the firmware toolchains mix code and data, but we can at least isolate these mappings so that they do not appear in the regular kernel page tables. In commit d2f7cbe7b26a ("x86/efi: Runtime services virtual mapping") we started using 'trampoline_pgd' to map the EFI regions because there was an existing identity mapping there which we use during the SetVirtualAddressMap() call and for broken firmware that accesses those addresses. But 'trampoline_pgd' shares some PGD entries with 'swapper_pg_dir' and does not provide the isolation we require. Notably the virtual address for __START_KERNEL_map and MODULES_START are mapped by the same PGD entry so we need to be more careful when copying changes over in efi_sync_low_kernel_mappings(). This patch doesn't go the full mile, we still want to share some PGD entries with 'swapper_pg_dir'. Having completely separate page tables brings its own issues such as synchronising new mappings after memory hotplug and module loading. Sharing also keeps memory usage down. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1448658575-17029-6-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29x86/efi: Hoist page table switching code into efi_call_virt()Matt Fleming
This change is a prerequisite for pending patches that switch to a dedicated EFI page table, instead of using 'trampoline_pgd' which shares PGD entries with 'swapper_pg_dir'. The pending patches make it impossible to dereference the runtime service function pointer without first switching %cr3. It's true that we now have duplicated switching code in efi_call_virt() and efi_call_phys_{prolog,epilog}() but we are sacrificing code duplication for a little more clarity and the ease of writing the page table switching code in C instead of asm. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1448658575-17029-5-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29x86/efi: Map RAM into the identity page table for mixed modeMatt Fleming
We are relying on the pre-existing mappings in 'trampoline_pgd' when accessing function arguments in the EFI mixed mode thunking code. Instead let's map memory explicitly so that things will continue to work when we move to a separate page table in the future. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1448658575-17029-4-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29x86/mm/pat: Ensure cpa->pfn only contains page frame numbersMatt Fleming
The x86 pageattr code is confused about the data that is stored in cpa->pfn, sometimes it's treated as a page frame number, sometimes it's treated as an unshifted physical address, and in one place it's treated as a pte. The result of this is that the mapping functions do not map the intended physical address. This isn't a problem in practice because most of the addresses we're mapping in the EFI code paths are already mapped in 'trampoline_pgd' and so the pageattr mapping functions don't actually do anything in this case. But when we move to using a separate page table for the EFI runtime this will be an issue. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1448658575-17029-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-28efi: Use correct type for struct efi_memory_map::phys_mapArd Biesheuvel
We have been getting away with using a void* for the physical address of the UEFI memory map, since, even on 32-bit platforms with 64-bit physical addresses, no truncation takes place if the memory map has been allocated by the firmware (which only uses 1:1 virtually addressable memory), which is usually the case. However, commit: 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option") adds code that clones and modifies the UEFI memory map, and the clone may live above 4 GB on 32-bit platforms. This means our use of void* for struct efi_memory_map::phys_map has graduated from 'incorrect but working' to 'incorrect and broken', and we need to fix it. So redefine struct efi_memory_map::phys_map as phys_addr_t, and get rid of a bunch of casts that are now unneeded. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: izumi.taku@jp.fujitsu.com Cc: kamezawa.hiroyu@jp.fujitsu.com Cc: linux-efi@vger.kernel.org Cc: matt.fleming@intel.com Link: http://lkml.kernel.org/r/1445593697-1342-1-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14Merge tag 'efi-next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into core/efi Pull v4.4 EFI updates from Matt Fleming: - Make the EFI System Resource Table (ESRT) driver explicitly non-modular by ripping out the module_* code since Kconfig doesn't allow it to be built as a module anyway. (Paul Gortmaker) - Make the x86 efi=debug kernel parameter, which enables EFI debug code and output, generic and usable by arm64. (Leif Lindholm) - Add support to the x86 EFI boot stub for 64-bit Graphics Output Protocol frame buffer addresses. (Matt Fleming) - Detect when the UEFI v2.5 EFI_PROPERTIES_TABLE feature is enabled in the firmware and set an efi.flags bit so the kernel knows when it can apply more strict runtime mapping attributes - Ard Biesheuvel - Auto-load the efi-pstore module on EFI systems, just like we currently do for the efivars module. (Ben Hutchings) - Add "efi_fake_mem" kernel parameter which allows the system's EFI memory map to be updated with additional attributes for specific memory ranges. This is useful for testing the kernel code that handles the EFI_MEMORY_MORE_RELIABLE memmap bit even if your firmware doesn't include support. (Taku Izumi) Note: there is a semantic conflict between the following two commits: 8a53554e12e9 ("x86/efi: Fix multiple GOP device support") ae2ee627dc87 ("efifb: Add support for 64-bit frame buffer addresses") I fixed up the interaction in the merge commit, changing the type of current_fb_base from u32 to u64. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14Merge branch 'x86/urgent' into core/efi, to pick up a pending EFI fixIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-12x86/efi: Rename print_efi_memmap() to efi_print_memmap()Taku Izumi
This patch renames print_efi_memmap() to efi_print_memmap() and make it global function so that we can invoke it outside of arch/x86/platform/efi/efi.c Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-12efi/x86: Move efi=debug option parsing to coreLeif Lindholm
fed6cefe3b6e ("x86/efi: Add a "debug" option to the efi= cmdline") adds the DBG flag, but does so for x86 only. Move this early param parsing to core code. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-01x86/efi: Fix boot crash by mapping EFI memmap entries bottom-up at runtime, ↵Matt Fleming
instead of top-down Beginning with UEFI v2.5 EFI_PROPERTIES_TABLE was introduced that signals that the firmware PE/COFF loader supports splitting code and data sections of PE/COFF images into separate EFI memory map entries. This allows the kernel to map those regions with strict memory protections, e.g. EFI_MEMORY_RO for code, EFI_MEMORY_XP for data, etc. Unfortunately, an unwritten requirement of this new feature is that the regions need to be mapped with the same offsets relative to each other as observed in the EFI memory map. If this is not done crashes like this may occur, BUG: unable to handle kernel paging request at fffffffefe6086dd IP: [<fffffffefe6086dd>] 0xfffffffefe6086dd Call Trace: [<ffffffff8104c90e>] efi_call+0x7e/0x100 [<ffffffff81602091>] ? virt_efi_set_variable+0x61/0x90 [<ffffffff8104c583>] efi_delete_dummy_variable+0x63/0x70 [<ffffffff81f4e4aa>] efi_enter_virtual_mode+0x383/0x392 [<ffffffff81f37e1b>] start_kernel+0x38a/0x417 [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef Here 0xfffffffefe6086dd refers to an address the firmware expects to be mapped but which the OS never claimed was mapped. The issue is that included in these regions are relative addresses to other regions which were emitted by the firmware toolchain before the "splitting" of sections occurred at runtime. Needless to say, we don't satisfy this unwritten requirement on x86_64 and instead map the EFI memory map entries in reverse order. The above crash is almost certainly triggerable with any kernel newer than v3.13 because that's when we rewrote the EFI runtime region mapping code, in commit d2f7cbe7b26a ("x86/efi: Runtime services virtual mapping"). For kernel versions before v3.13 things may work by pure luck depending on the fragmentation of the kernel virtual address space at the time we map the EFI regions. Instead of mapping the EFI memory map entries in reverse order, where entry N has a higher virtual address than entry N+1, map them in the same order as they appear in the EFI memory map to preserve this relative offset between regions. This patch has been kept as small as possible with the intention that it should be applied aggressively to stable and distribution kernels. It is very much a bugfix rather than support for a new feature, since when EFI_PROPERTIES_TABLE is enabled we must map things as outlined above to even boot - we have no way of asking the firmware not to split the code/data regions. In fact, this patch doesn't even make use of the more strict memory protections available in UEFI v2.5. That will come later. Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Cc: <stable@vger.kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Chun-Yi <jlee@suse.com> Cc: Dave Young <dyoung@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: James Bottomley <JBottomley@Odin.com> Cc: Lee, Chun-Yi <jlee@suse.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1443218539-7610-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-10kexec: split kexec_load syscall from kexec core codeDave Young
There are two kexec load syscalls, kexec_load another and kexec_file_load. kexec_file_load has been splited as kernel/kexec_file.c. In this patch I split kexec_load syscall code to kernel/kexec.c. And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and use kexec_file_load only, or vice verse. The original requirement is from Ted Ts'o, he want kexec kernel signature being checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use kexec_load syscall can bypass the checking. Vivek Goyal proposed to create a common kconfig option so user can compile in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects KEXEC_CORE so that old config files still work. Because there's general code need CONFIG_KEXEC_CORE, so I updated all the architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects KEXEC_CORE in arch Kconfig. Also updated general kernel code with to kexec_load syscall. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Petr Tesarik <ptesarik@suse.cz> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Josh Boyer <jwboyer@fedoraproject.org> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-08efi, x86: Rearrange efi_mem_attributes()Jonathan (Zhixiong) Zhang
x86 and ia64 implement efi_mem_attributes() differently. This function needs to be available for other architectures (such as arm64) as well, such as for the purpose of ACPI/APEI. ia64 EFI does not set up a 'memmap' variable and does not set the EFI_MEMMAP flag, so it needs to have its unique implementation of efi_mem_attributes(). Move efi_mem_attributes() implementation from x86 to the core EFI code, and declare it with __weak. It is recommended that other architectures should not override the default implementation. Signed-off-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Reviewed-by: Matt Fleming <matt.fleming@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1438936621-5215-4-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-08x86/efi-bgrt: Switch pr_err() to pr_debug() for invalid BGRTMatt Fleming
It's totally legitimate, per the ACPI spec, for the firmware to set the BGRT 'status' field to zero to indicate that the BGRT image isn't being displayed, and we shouldn't be printing an error message in that case because it's just noise for users. So swap pr_err() for pr_debug(). However, Josh points that out it still makes sense to test the validity of the upper 7 bits of the 'status' field, since they're marked as "reserved" in the spec and must be zero. If firmware violates this it really *is* an error. Reported-by: Tom Yan <tom.ty89@gmail.com> Tested-by: Tom Yan <tom.ty89@gmail.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1438936621-5215-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-30efi: Check for NULL efi kernel parametersRicardo Neri
Even though it is documented how to specifiy efi parameters, it is possible to cause a kernel panic due to a dereference of a NULL pointer when parsing such parameters if "efi" alone is given: PANIC: early exception 0e rip 10:ffffffff812fb361 error 0 cr2 0 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.2.0-rc1+ #450 [ 0.000000] ffffffff81fe20a9 ffffffff81e03d50 ffffffff8184bb0f 00000000000003f8 [ 0.000000] 0000000000000000 ffffffff81e03e08 ffffffff81f371a1 64656c62616e6520 [ 0.000000] 0000000000000069 000000000000005f 0000000000000000 0000000000000000 [ 0.000000] Call Trace: [ 0.000000] [<ffffffff8184bb0f>] dump_stack+0x45/0x57 [ 0.000000] [<ffffffff81f371a1>] early_idt_handler_common+0x81/0xae [ 0.000000] [<ffffffff812fb361>] ? parse_option_str+0x11/0x90 [ 0.000000] [<ffffffff81f4dd69>] arch_parse_efi_cmdline+0x15/0x42 [ 0.000000] [<ffffffff81f376e1>] do_early_param+0x50/0x8a [ 0.000000] [<ffffffff8106b1b3>] parse_args+0x1e3/0x400 [ 0.000000] [<ffffffff81f37a43>] parse_early_options+0x24/0x28 [ 0.000000] [<ffffffff81f37691>] ? loglevel+0x31/0x31 [ 0.000000] [<ffffffff81f37a78>] parse_early_param+0x31/0x3d [ 0.000000] [<ffffffff81f3ae98>] setup_arch+0x2de/0xc08 [ 0.000000] [<ffffffff8109629a>] ? vprintk_default+0x1a/0x20 [ 0.000000] [<ffffffff81f37b20>] start_kernel+0x90/0x423 [ 0.000000] [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c [ 0.000000] [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef [ 0.000000] RIP 0xffffffff81ba2efc This panic is not reproducible with "efi=" as this will result in a non-NULL zero-length string. Thus, verify that the pointer to the parameter string is not NULL. This is consistent with other parameter-parsing functions which check for NULL pointers. Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-06-29Merge tag 'libnvdimm-for-4.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm Pull libnvdimm subsystem from Dan Williams: "The libnvdimm sub-system introduces, in addition to the libnvdimm-core, 4 drivers / enabling modules: NFIT: Instantiates an "nvdimm bus" with the core and registers memory devices (NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware Interface table). After registering NVDIMMs the NFIT driver then registers "region" devices. A libnvdimm-region defines an access mode and the boundaries of persistent memory media. A region may span multiple NVDIMMs that are interleaved by the hardware memory controller. In turn, a libnvdimm-region can be carved into a "namespace" device and bound to the PMEM or BLK driver which will attach a Linux block device (disk) interface to the memory. PMEM: Initially merged in v4.1 this driver for contiguous spans of persistent memory address ranges is re-worked to drive PMEM-namespaces emitted by the libnvdimm-core. In this update the PMEM driver, on x86, gains the ability to assert that writes to persistent memory have been flushed all the way through the caches and buffers in the platform to persistent media. See memcpy_to_pmem() and wmb_pmem(). BLK: This new driver enables access to persistent memory media through "Block Data Windows" as defined by the NFIT. The primary difference of this driver to PMEM is that only a small window of persistent memory is mapped into system address space at any given point in time. Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access different portions of the media. BLK-mode, by definition, does not support DAX. BTT: This is a library, optionally consumed by either PMEM or BLK, that converts a byte-accessible namespace into a disk with atomic sector update semantics (prevents sector tearing on crash or power loss). The sinister aspect of sector tearing is that most applications do not know they have a atomic sector dependency. At least today's disk's rarely ever tear sectors and if they do one almost certainly gets a CRC error on access. NVDIMMs will always tear and always silently. Until an application is audited to be robust in the presence of sector-tearing the usage of BTT is recommended. Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig, Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox, Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael Wysocki, and Bob Moore" * tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: (33 commits) arch, x86: pmem api for ensuring durability of persistent memory updates libnvdimm: Add sysfs numa_node to NVDIMM devices libnvdimm: Set numa_node to NVDIMM devices acpi: Add acpi_map_pxm_to_online_node() libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only pmem: flag pmem block devices as non-rotational libnvdimm: enable iostat pmem: make_request cleanups libnvdimm, pmem: fix up max_hw_sectors libnvdimm, blk: add support for blk integrity libnvdimm, btt: add support for blk integrity fs/block_dev.c: skip rw_page if bdev has integrity libnvdimm: Non-Volatile Devices tools/testing/nvdimm: libnvdimm unit test infrastructure libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory nd_btt: atomic sector updates libnvdimm: infrastructure for btt devices libnvdimm: write blk label set libnvdimm: write pmem label set libnvdimm: blk labels and namespace instantiation ...
2015-06-24x86, mirror: x86 enabling - find mirrored memory rangesTony Luck
UEFI GetMemoryMap() uses a new attribute bit to mark mirrored memory address ranges. See UEFI 2.5 spec pages 157-158: http://www.uefi.org/sites/default/files/resources/UEFI%202_5.pdf On EFI enabled systems scan the memory map and tell memblock about any mirrored ranges. Signed-off-by: Tony Luck <tony.luck@intel.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Xiexiuqi <xiexiuqi@huawei.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-05-27e820, efi: add ACPI 6.0 persistent memory typesDan Williams
ACPI 6.0 formalizes e820-type-7 and efi-type-14 as persistent memory. Mark it "reserved" and allow it to be claimed by a persistent memory device driver. This definition is in addition to the Linux kernel's existing type-12 definition that was recently added in support of shipping platforms with NVDIMM support that predate ACPI 6.0 (which now classifies type-12 as OEM reserved). Note, /proc/iomem can be consulted for differentiating legacy "Persistent Memory (legacy)" E820_PRAM vs standard "Persistent Memory" E820_PMEM. Cc: Boaz Harrosh <boaz@plexistor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jens Axboe <axboe@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Jeff Moyer <jmoyer@redhat.com> Acked-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-04-30efi: Add esrt supportPeter Jones
Add sysfs files for the EFI System Resource Table (ESRT) under /sys/firmware/efi/esrt and for each EFI System Resource Entry under entries/ as a subdir. The EFI System Resource Table (ESRT) provides a read-only catalog of system components for which the system accepts firmware upgrades via UEFI's "Capsule Update" feature. This module allows userland utilities to evaluate what firmware updates can be applied to this system, and potentially arrange for those updates to occur. The ESRT is described as part of the UEFI specification, in version 2.5 which should be available from http://uefi.org/specifications in early 2015. If you're a member of the UEFI Forum, information about its addition to the standard is available as UEFI Mantis 1090. For some hardware platforms, additional restrictions may be found at http://msdn.microsoft.com/en-us/library/windows/hardware/jj128256.aspx , and additional documentation may be found at http://download.microsoft.com/download/5/F/5/5F5D16CD-2530-4289-8019-94C6A20BED3C/windows-uefi-firmware-update-platform.docx . Signed-off-by: Peter Jones <pjones@redhat.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-04-13Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm changes from Ingo Molnar: "The main changes in this cycle were: - reduce the x86/32 PAE per task PGD allocation overhead from 4K to 0.032k (Fenghua Yu) - early_ioremap/memunmap() usage cleanups (Juergen Gross) - gbpages support cleanups (Luis R Rodriguez) - improve AMD Bulldozer (family 0x15) ASLR I$ aliasing workaround to increase randomization by 3 bits (per bootup) (Hector Marco-Gisbert) - misc fixlets" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Improve AMD Bulldozer ASLR workaround x86/mm/pat: Initialize __cachemode2pte_tbl[] and __pte2cachemode_tbl[] in a bit more readable fashion init.h: Clean up the __setup()/early_param() macros x86/mm: Simplify probe_page_size_mask() x86/mm: Further simplify 1 GB kernel linear mappings handling x86/mm: Use early_param_on_off() for direct_gbpages init.h: Add early_param_on_off() x86/mm: Simplify enabling direct_gbpages x86/mm: Use IS_ENABLED() for direct_gbpages x86/mm: Unexport set_memory_ro() and set_memory_rw() x86/mm, efi: Use early_ioremap() in arch/x86/platform/efi/efi-bgrt.c x86/mm: Use early_memunmap() instead of early_iounmap() x86/mm/pat: Ensure different messages in STRICT_DEVMEM and PAT cases x86/mm: Reduce PAE-mode per task pgd allocation overhead from 4K to 32 bytes