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path: root/drivers/firmware/efi/efi.c
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2022-04-13efi: Register efi_secret platform device if EFI secret area is declaredDov Murik1-0/+5
During efi initialization, check if coco_secret is defined in the EFI configuration table; in such case, register platform device "efi_secret". This allows udev to automatically load the efi_secret module (platform driver), which in turn will populate the <securityfs>/secrets/coco directory in guests into which secrets were injected. Note that a declared address of an EFI secret area doesn't mean that secrets where indeed injected to that area; if the secret area is not populated, the driver will not load (but the platform device will still be registered). Signed-off-by: Dov Murik <dovmurik@linux.ibm.com> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Link: https://lore.kernel.org/r/20220412212127.154182-4-dovmurik@linux.ibm.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-04-13efi: Save location of EFI confidential computing areaDov Murik1-0/+6
Confidential computing (coco) hardware such as AMD SEV (Secure Encrypted Virtualization) allows a guest owner to inject secrets into the VMs memory without the host/hypervisor being able to read them. Firmware support for secret injection is available in OVMF, which reserves a memory area for secret injection and includes a pointer to it the in EFI config table entry LINUX_EFI_COCO_SECRET_TABLE_GUID. If EFI exposes such a table entry, uefi_init() will keep a pointer to the EFI config table entry in efi.coco_secret, so it can be used later by the kernel (specifically drivers/virt/coco/efi_secret). It will also appear in the kernel log as "CocoSecret=ADDRESS"; for example: [ 0.000000] efi: EFI v2.70 by EDK II [ 0.000000] efi: CocoSecret=0x7f22e680 SMBIOS=0x7f541000 ACPI=0x7f77e000 ACPI 2.0=0x7f77e014 MEMATTR=0x7ea0c018 The new functionality can be enabled with CONFIG_EFI_COCO_SECRET=y. Signed-off-by: Dov Murik <dovmurik@linux.ibm.com> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Link: https://lore.kernel.org/r/20220412212127.154182-2-dovmurik@linux.ibm.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-04-13efi: Allow to enable EFI runtime services by default on RTJavier Martinez Canillas1-1/+1
Commit d9f283ae71af ("efi: Disable runtime services on RT") disabled EFI runtime services by default when the CONFIG_PREEMPT_RT option is enabled. The rationale for that commit is that some EFI calls could take too much time, leading to large latencies which is an issue for Real-Time kernels. But a side effect of that change was that now is not possible anymore to enable the EFI runtime services by default when CONFIG_PREEMPT_RT is set, without passing an efi=runtime command line parameter to the kernel. Instead, let's add a new EFI_DISABLE_RUNTIME boolean Kconfig option, that would be set to n by default but to y if CONFIG_PREEMPT_RT is enabled. That way, the current behaviour is preserved but gives users a mechanism to enable the EFI runtimes services in their kernels if that is required. For example, if the firmware could guarantee bounded time for EFI calls. Also, having a separate boolean config could allow users to disable the EFI runtime services by default even when CONFIG_PREEMPT_RT is not set. Reported-by: Alexander Larsson <alexl@redhat.com> Fixes: d9f283ae71af ("efi: Disable runtime services on RT") Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20220331151654.184433-1-javierm@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-03-01efi: fix return value of __setup handlersRandy Dunlap1-1/+1
When "dump_apple_properties" is used on the kernel boot command line, it causes an Unknown parameter message and the string is added to init's argument strings: Unknown kernel command line parameters "dump_apple_properties BOOT_IMAGE=/boot/bzImage-517rc6 efivar_ssdt=newcpu_ssdt", will be passed to user space. Run /sbin/init as init process with arguments: /sbin/init dump_apple_properties with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc6 efivar_ssdt=newcpu_ssdt Similarly when "efivar_ssdt=somestring" is used, it is added to the Unknown parameter message and to init's environment strings, polluting them (see examples above). Change the return value of the __setup functions to 1 to indicate that the __setup options have been handled. Fixes: 58c5475aba67 ("x86/efi: Retrieve and assign Apple device properties") Fixes: 475fb4e8b2f4 ("efi / ACPI: load SSTDs from EFI variables") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Cc: Ard Biesheuvel <ardb@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Lukas Wunner <lukas@wunner.de> Cc: Octavian Purdila <octavian.purdila@intel.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Link: https://lore.kernel.org/r/20220301041851.12459-1-rdunlap@infradead.org Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-01-23efi: runtime: avoid EFIv2 runtime services on Apple x86 machinesArd Biesheuvel1-0/+7
Aditya reports [0] that his recent MacbookPro crashes in the firmware when using the variable services at runtime. The culprit appears to be a call to QueryVariableInfo(), which we did not use to call on Apple x86 machines in the past as they only upgraded from EFI v1.10 to EFI v2.40 firmware fairly recently, and QueryVariableInfo() (along with UpdateCapsule() et al) was added in EFI v2.00. The only runtime service introduced in EFI v2.00 that we actually use in Linux is QueryVariableInfo(), as the capsule based ones are optional, generally not used at runtime (all the LVFS/fwupd firmware update infrastructure uses helper EFI programs that invoke capsule update at boot time, not runtime), and not implemented by Apple machines in the first place. QueryVariableInfo() is used to 'safely' set variables, i.e., only when there is enough space. This prevents machines with buggy firmwares from corrupting their NVRAMs when they run out of space. Given that Apple machines have been using EFI v1.10 services only for the longest time (the EFI v2.0 spec was released in 2006, and Linux support for the newly introduced runtime services was added in 2011, but the MacbookPro12,1 released in 2015 still claims to be EFI v1.10 only), let's avoid the EFI v2.0 ones on all Apple x86 machines. [0] https://lore.kernel.org/all/6D757C75-65B1-468B-842D-10410081A8E4@live.com/ Cc: <stable@vger.kernel.org> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Reported-by: Aditya Garg <gargaditya08@live.com> Tested-by: Orlando Chamberlain <redecorating@protonmail.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Aditya Garg <gargaditya08@live.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=215277
2021-09-28efi: Allow efi=runtimeSebastian Andrzej Siewior1-0/+3
In case the command line option "efi=noruntime" is default at built-time, the user could overwrite its state by `efi=runtime' and allow it again. This is useful on PREEMPT_RT where "efi=noruntime" is default and the user might need to alter the boot order for instance. Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-09-28efi: Disable runtime services on RTSebastian Andrzej Siewior1-1/+1
Based on measurements the EFI functions get_variable / get_next_variable take up to 2us which looks okay. The functions get_time, set_time take around 10ms. These 10ms are too much. Even one ms would be too much. Ard mentioned that SetVariable might even trigger larger latencies if the firmware will erase flash blocks on NOR. The time-functions are used by efi-rtc and can be triggered during run-time (either via explicit read/write or ntp sync). The variable write could be used by pstore. These functions can be disabled without much of a loss. The poweroff / reboot hooks may be provided by PSCI. Disable EFI's runtime wrappers on PREEMPT_RT. This was observed on "EFI v2.60 by SoftIron Overdrive 1000". Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-07-16firmware/efi: Tell memblock about EFI iomem reservationsMarc Zyngier1-1/+12
kexec_load_file() relies on the memblock infrastructure to avoid stamping over regions of memory that are essential to the survival of the system. However, nobody seems to agree how to flag these regions as reserved, and (for example) EFI only publishes its reservations in /proc/iomem for the benefit of the traditional, userspace based kexec tool. On arm64 platforms with GICv3, this can result in the payload being placed at the location of the LPI tables. Shock, horror! Let's augment the EFI reservation code with a memblock_reserve() call, protecting our dear tables from the secondary kernel invasion. Reported-by: Moritz Fischer <mdf@kernel.org> Tested-by: Moritz Fischer <mdf@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Cc: Ard Biesheuvel <ardb@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-03-19firmware/efi: Fix a use after bug in efi_mem_reserve_persistentLv Yunlong1-1/+2
In the for loop in efi_mem_reserve_persistent(), prsv = rsv->next use the unmapped rsv. Use the unmapped pages will cause segment fault. Fixes: 18df7577adae6 ("efi/memreserve: deal with memreserve entries in unmapped memory") Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-12-15mm/gup: prevent gup_fast from racing with COW during forkJason Gunthorpe1-0/+1
Since commit 70e806e4e645 ("mm: Do early cow for pinned pages during fork() for ptes") pages under a FOLL_PIN will not be write protected during COW for fork. This means that pages returned from pin_user_pages(FOLL_WRITE) should not become write protected while the pin is active. However, there is a small race where get_user_pages_fast(FOLL_PIN) can establish a FOLL_PIN at the same time copy_present_page() is write protecting it: CPU 0 CPU 1 get_user_pages_fast() internal_get_user_pages_fast() copy_page_range() pte_alloc_map_lock() copy_present_page() atomic_read(has_pinned) == 0 page_maybe_dma_pinned() == false atomic_set(has_pinned, 1); gup_pgd_range() gup_pte_range() pte_t pte = gup_get_pte(ptep) pte_access_permitted(pte) try_grab_compound_head() pte = pte_wrprotect(pte) set_pte_at(); pte_unmap_unlock() // GUP now returns with a write protected page The first attempt to resolve this by using the write protect caused problems (and was missing a barrrier), see commit f3c64eda3e50 ("mm: avoid early COW write protect games during fork()") Instead wrap copy_p4d_range() with the write side of a seqcount and check the read side around gup_pgd_range(). If there is a collision then get_user_pages_fast() fails and falls back to slow GUP. Slow GUP is safe against this race because copy_page_range() is only called while holding the exclusive side of the mmap_lock on the src mm_struct. [akpm@linux-foundation.org: coding style fixes] Link: https://lore.kernel.org/r/CAHk-=wi=iCnYCARbPGjkVJu9eyYeZ13N64tZYLdOB8CP5Q_PLw@mail.gmail.com Link: https://lkml.kernel.org/r/2-v4-908497cf359a+4782-gup_fork_jgg@nvidia.com Fixes: f3c64eda3e50 ("mm: avoid early COW write protect games during fork()") Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Peter Xu <peterx@redhat.com> Acked-by: "Ahmed S. Darwish" <a.darwish@linutronix.de> [seqcount_t parts] Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hugh Dickins <hughd@google.com> Cc: Jann Horn <jannh@google.com> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Leon Romanovsky <leonro@nvidia.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-25efi/efivars: Set generic ops before loading SSDTAmadeusz Sławiński1-1/+1
Efivars allows for overriding of SSDT tables, however starting with commit bf67fad19e493b ("efi: Use more granular check for availability for variable services") this use case is broken. When loading SSDT generic ops should be set first, however mentioned commit reversed order of operations. Fix this by restoring original order of operations. Fixes: bf67fad19e493b ("efi: Use more granular check for availability for variable services") Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com> Link: https://lore.kernel.org/r/20201123172817.124146-1-amadeuszx.slawinski@linux.intel.com Tested-by: Cezary Rojewski <cezary.rojewski@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-10-12Merge branch 'efi/urgent' into efi/core, to pick up fixesIngo Molnar1-23/+26
These fixes missed the v5.9 merge window, pick them up for early v5.10 merge. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-09-25efi: Add definition of EFI_MEMORY_CPU_CRYPTO and ability to report itArd Biesheuvel1-23/+24
Incorporate the definition of EFI_MEMORY_CPU_CRYPTO from the UEFI specification v2.8, and wire it into our memory map dumping routine as well. To make a bit of space in the output buffer, which is provided by the various callers, shorten the descriptive names of the memory types. Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-09-16efi: Support for MOK variable config tableLenny Szubowicz1-0/+6
Because of system-specific EFI firmware limitations, EFI volatile variables may not be capable of holding the required contents of the Machine Owner Key (MOK) certificate store when the certificate list grows above some size. Therefore, an EFI boot loader may pass the MOK certs via a EFI configuration table created specifically for this purpose to avoid this firmware limitation. An EFI configuration table is a much more primitive mechanism compared to EFI variables and is well suited for one-way passage of static information from a pre-OS environment to the kernel. This patch adds initial kernel support to recognize, parse, and validate the EFI MOK configuration table, where named entries contain the same data that would otherwise be provided in similarly named EFI variables. Additionally, this patch creates a sysfs binary file for each EFI MOK configuration table entry found. These files are read-only to root and are provided for use by user space utilities such as mokutil. A subsequent patch will load MOK certs into the trusted platform key ring using this infrastructure. Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com> Link: https://lore.kernel.org/r/20200905013107.10457-2-lszubowi@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-08-20efi: add missed destroy_workqueue when efisubsys_init failsLi Heng1-0/+2
destroy_workqueue() should be called to destroy efi_rts_wq when efisubsys_init() init resources fails. Cc: <stable@vger.kernel.org> Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Li Heng <liheng40@huawei.com> Link: https://lore.kernel.org/r/1595229738-10087-1-git-send-email-liheng40@huawei.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-07-09efi/efivars: Expose RT service availability via efivars abstractionArd Biesheuvel1-4/+8
Commit bf67fad19e493b ("efi: Use more granular check for availability for variable services") introduced a check into the efivarfs, efi-pstore and other drivers that aborts loading of the module if not all three variable runtime services (GetVariable, SetVariable and GetNextVariable) are supported. However, this results in efivarfs being unavailable entirely if only SetVariable support is missing, which is only needed if you want to make any modifications. Also, efi-pstore and the sysfs EFI variable interface could be backed by another implementation of the 'efivars' abstraction, in which case it is completely irrelevant which services are supported by the EFI firmware. So make the generic 'efivars' abstraction dependent on the availibility of the GetVariable and GetNextVariable EFI runtime services, and add a helper 'efivar_supports_writes()' to find out whether the currently active efivars abstraction supports writes (and wire it up to the availability of SetVariable for the generic one). Then, use the efivar_supports_writes() helper to decide whether to permit efivarfs to be mounted read-write, and whether to enable efi-pstore or the sysfs EFI variable interface altogether. Fixes: bf67fad19e493b ("efi: Use more granular check for availability for variable services") Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-16efi: Make it possible to disable efivar_ssdt entirelyPeter Jones1-1/+1
In most cases, such as CONFIG_ACPI_CUSTOM_DSDT and CONFIG_ACPI_TABLE_UPGRADE, boot-time modifications to firmware tables are tied to specific Kconfig options. Currently this is not the case for modifying the ACPI SSDT via the efivar_ssdt kernel command line option and associated EFI variable. This patch adds CONFIG_EFI_CUSTOM_SSDT_OVERLAYS, which defaults disabled, in order to allow enabling or disabling that feature during the build. Cc: <stable@vger.kernel.org> Signed-off-by: Peter Jones <pjones@redhat.com> Link: https://lore.kernel.org/r/20200615202408.2242614-1-pjones@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-15efi: Replace zero-length array and use struct_size() helperGustavo A. R. Silva1-1/+2
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. Lastly, make use of the sizeof_field() helper instead of an open-coded version. This issue was found with the help of Coccinelle and audited _manually_. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20200527171425.GA4053@embeddedor Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-09mmap locking API: add MMAP_LOCK_INITIALIZERMichel Lespinasse1-1/+1
Define a new initializer for the mmap locking api. Initially this just evaluates to __RWSEM_INITIALIZER as the API is defined as wrappers around rwsem. Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-9-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-25Merge tag 'v5.7-rc7' into efi/core, to refresh the branch and pick up fixesIngo Molnar1-4/+1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-05-17efi: Pull up arch-specific prototype efi_systab_show_arch()Benjamin Thiel1-4/+1
Pull up arch-specific prototype efi_systab_show_arch() in order to fix a -Wmissing-prototypes warning: arch/x86/platform/efi/efi.c:957:7: warning: no previous prototype for ‘efi_systab_show_arch’ [-Wmissing-prototypes] char *efi_systab_show_arch(char *str) Signed-off-by: Benjamin Thiel <b.thiel@posteo.de> Link: https://lore.kernel.org/r/20200516132647.14568-1-b.thiel@posteo.de Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24efi: Move arch_tables check to callerArd Biesheuvel1-10/+8
Instead of making match_config_table() test its table_types pointer for NULL-ness, omit the call entirely if no arch_tables pointer was provided to efi_config_parse_tables(). Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-24efi: Clean up config table description arraysArd Biesheuvel1-14/+14
Increase legibility by adding whitespace to the efi_config_table_type_t arrays that describe which EFI config tables we look for when going over the firmware provided list. While at it, replace the 'name' char pointer with a char array, which is more space efficient on relocatable 64-bit kernels, as it avoids a 8 byte pointer and the associated relocation data (24 bytes when using RELA format) Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-03-08efi/x86: Ignore the memory attributes table on i386Ard Biesheuvel1-1/+1
Commit: 3a6b6c6fb23667fa ("efi: Make EFI_MEMORY_ATTRIBUTES_TABLE initialization common across all architectures") moved the call to efi_memattr_init() from ARM specific to the generic EFI init code, in order to be able to apply the restricted permissions described in that table on x86 as well. We never enabled this feature fully on i386, and so mapping and reserving this table is pointless. However, due to the early call to memblock_reserve(), the memory bookkeeping gets confused to the point where it produces the splat below when we try to map the memory later on: ------------[ cut here ]------------ ioremap on RAM at 0x3f251000 - 0x3fa1afff WARNING: CPU: 0 PID: 0 at arch/x86/mm/ioremap.c:166 __ioremap_caller ... Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.20.0 #48 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 EIP: __ioremap_caller.constprop.0+0x249/0x260 Code: 90 0f b7 05 4e 38 40 de 09 45 e0 e9 09 ff ff ff 90 8d 45 ec c6 05 ... EAX: 00000029 EBX: 00000000 ECX: de59c228 EDX: 00000001 ESI: 3f250fff EDI: 00000000 EBP: de3edf20 ESP: de3edee0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00200296 CR0: 80050033 CR2: ffd17000 CR3: 1e58c000 CR4: 00040690 Call Trace: ioremap_cache+0xd/0x10 ? old_map_region+0x72/0x9d old_map_region+0x72/0x9d efi_map_region+0x8/0xa efi_enter_virtual_mode+0x260/0x43b start_kernel+0x329/0x3aa i386_start_kernel+0xa7/0xab startup_32_smp+0x164/0x168 ---[ end trace e15ccf6b9f356833 ]--- Let's work around this by disregarding the memory attributes table altogether on i386, which does not result in a loss of functionality or protection, given that we never consumed the contents. Fixes: 3a6b6c6fb23667fa ("efi: Make EFI_MEMORY_ATTRIBUTES_TABLE ... ") Tested-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200304165917.5893-1-ardb@kernel.org Link: https://lore.kernel.org/r/20200308080859.21568-21-ardb@kernel.org
2020-03-08Merge branch 'efi/urgent' into efi/core, to pick up fixesIngo Molnar1-2/+2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-08Merge tag 'efi-next' of ↵Ingo Molnar1-0/+57
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core More EFI updates for v5.7 - Incorporate a stable branch with the EFI pieces of Hans's work on loading device firmware from EFI boot service memory regions Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-03efi: Export boot-services code and data as debugfs-blobsHans de Goede1-0/+57
Sometimes it is useful to be able to dump the efi boot-services code and data. This commit adds these as debugfs-blobs to /sys/kernel/debug/efi, but only if efi=debug is passed on the kernel-commandline as this requires not freeing those memory-regions, which costs 20+ MB of RAM. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200115163554.101315-2-hdegoede@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-29efi: Mark all EFI runtime services as unsupported on non-EFI bootArd Biesheuvel1-3/+3
Recent changes to the way we deal with EFI runtime services that are marked as unsupported by the firmware resulted in a regression for non-EFI boot. The problem is that all EFI runtime services are marked as available by default, and any non-NULL checks on the EFI service function pointers (which will be non-NULL even for runtime services that are unsupported on an EFI boot) were replaced with checks against the mask stored in efi.runtime_supported_mask. When doing a non-EFI boot, this check against the mask will return a false positive, given the fact that all runtime services are marked as enabled by default. Since we dropped the non-NULL check of the runtime service function pointer in favor of the mask check, we will now unconditionally dereference the function pointer, even if it is NULL, and go boom. So let's ensure that the mask reflects reality on a non-EFI boot, which is that all EFI runtime services are unsupported. Reported-by: David Hildenbrand <david@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-7-ardb@kernel.org
2020-02-29efi: Don't shadow 'i' in efi_config_parse_tables()Heinrich Schuchardt1-1/+0
Shadowing variables is generally frowned upon. Let's simply reuse the existing loop counter 'i' instead of shadowing it. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200223221324.156086-1-xypron.glpk@gmx.de Link: https://lore.kernel.org/r/20200228121408.9075-4-ardb@kernel.org
2020-02-29efi/x86: Add RNG seed EFI table to unencrypted mapping checkTom Lendacky1-8/+10
When booting with SME active, EFI tables must be mapped unencrypted since they were built by UEFI in unencrypted memory. Update the list of tables to be checked during early_memremap() processing to account for the EFI RNG seed table. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Link: https://lore.kernel.org/r/b64385fc13e5d7ad4b459216524f138e7879234f.1582662842.git.thomas.lendacky@amd.com Link: https://lore.kernel.org/r/20200228121408.9075-3-ardb@kernel.org
2020-02-26efi: READ_ONCE rng seed size before munmapJason A. Donenfeld1-2/+2
This function is consistent with using size instead of seed->size (except for one place that this patch fixes), but it reads seed->size without using READ_ONCE, which means the compiler might still do something unwanted. So, this commit simply adds the READ_ONCE wrapper. Fixes: 636259880a7e ("efi: Add support for seeding the RNG from a UEFI ...") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20200217123354.21140-1-Jason@zx2c4.com Link: https://lore.kernel.org/r/20200221084849.26878-5-ardb@kernel.org
2020-02-23efi: Register EFI rtc platform device only when availableArd Biesheuvel1-0/+3
Drop the separate driver that registers the EFI rtc on all EFI systems that have runtime services available, and instead, move the registration into the core EFI code, and make it conditional on whether the actual time related services are available. Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Use more granular check for availability for variable servicesArd Biesheuvel1-20/+8
The UEFI spec rev 2.8 permits firmware implementations to support only a subset of EFI runtime services at OS runtime (i.e., after the call to ExitBootServices()), so let's take this into account in the drivers that rely specifically on the availability of the EFI variable services. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Add support for EFI_RT_PROPERTIES tableArd Biesheuvel1-0/+12
Take the newly introduced EFI_RT_PROPERTIES_TABLE configuration table into account, which carries a mask of which EFI runtime services are still functional after ExitBootServices() has been called by the OS. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Store mask of supported runtime services in struct efiArd Biesheuvel1-10/+17
Revision 2.8 of the UEFI spec introduces provisions for firmware to advertise lack of support for certain runtime services at OS runtime. Let's store this mask in struct efi for easy access. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/arm: Move FDT param discovery code out of efi.cArd Biesheuvel1-135/+0
On ARM systems, we discover the UEFI system table address and memory map address from the /chosen node in the device tree, or in the Xen case, from a similar node under /hypervisor. Before making some functional changes to that code, move it into its own file that only gets built if CONFIG_EFI_PARAMS_FROM_FDT=y. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/x86: Make fw_vendor, config_table and runtime sysfs nodes x86 specificArd Biesheuvel1-34/+6
There is some code that exposes physical addresses of certain parts of the EFI firmware implementation via sysfs nodes. These nodes are only used on x86, and are of dubious value to begin with, so let's move their handling into the x86 arch code. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Clean up config_parse_tables()Ard Biesheuvel1-24/+23
config_parse_tables() is a jumble of pointer arithmetic, due to the fact that on x86, we may be dealing with firmware whose native word size differs from the kernel's. This is not a concern on other architectures, and doesn't quite justify the state of the code, so let's clean it up by adding a non-x86 code path, constifying statically allocated tables and replacing preprocessor conditionals with IS_ENABLED() checks. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Make efi_config_init() x86 onlyArd Biesheuvel1-31/+0
The efi_config_init() routine is no longer shared with ia64 so let's move it into the x86 arch code before making further x86 specific changes to it. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Merge EFI system table revision and vendor checksArd Biesheuvel1-0/+61
We have three different versions of the code that checks the EFI system table revision and copies the firmware vendor string, and they are mostly equivalent, with the exception of the use of early_memremap_ro vs. __va() and the lowest major revision to warn about. Let's move this into common code and factor out the commonalities. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Make memreserve table handling local to efi.cArd Biesheuvel1-6/+6
There is no need for struct efi to carry the address of the memreserve table and share it with the world. So move it out and make it __initdata as well. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Move mem_attr_table out of struct efiArd Biesheuvel1-2/+1
The memory attributes table is only used at init time by the core EFI code, so there is no need to carry its address in struct efi that is shared with the world. So move it out, and make it __ro_after_init as well, considering that the value is set during early boot. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Make rng_seed table handling local to efi.cArd Biesheuvel1-11/+10
Move the rng_seed table address from struct efi into a static global variable in efi.c, which is the only place we ever refer to it anyway. This reduces the footprint of struct efi, which is a r/w data structure that is shared with the world. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Move UGA and PROP table handling to x86 codeArd Biesheuvel1-24/+1
The UGA table is x86 specific (its handling was introduced when the EFI support code was modified to accommodate IA32), so there is no need to handle it in generic code. The EFI properties table is not strictly x86 specific, but it was deprecated almost immediately after having been introduced, due to implementation difficulties. Only x86 takes it into account today, and this is not going to change, so make this table x86 only as well. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/ia64: Move HCDP and MPS table handling into IA64 arch codeArd Biesheuvel1-8/+6
The HCDP and MPS tables are Itanium specific EFI config tables, so move their handling to ia64 arch code. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi: Drop handling of 'boot_info' configuration tableArd Biesheuvel1-3/+0
Some plumbing exists to handle a UEFI configuration table of type BOOT_INFO but since we never match it to a GUID anywhere, we never actually register such a table, or access it, for that matter. So simply drop all mentions of it. Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64 Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-01-20efi: Fix comment for efi_mem_type() wrt absent physical addressesAnshuman Khandual1-1/+1
A previous commit f99afd08a45f ("efi: Update efi_mem_type() to return an error rather than 0") changed the return value from EFI_RESERVED_TYPE to -EINVAL when the searched physical address is not present in any memory descriptor. But the comment preceding the function never changed. Let's change the comment now to reflect the new return value -EINVAL. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-10-ardb@kernel.org
2019-12-17Merge branch 'efi-urgent-for-linus' of ↵Linus Torvalds1-2/+26
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Ingo Molnar: "Protect presistent EFI memory reservations from kexec, fix EFIFB early console, EFI stub graphics output fixes and other misc fixes." * 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi: Don't attempt to map RCI2 config table if it doesn't exist efi/earlycon: Remap entire framebuffer after page initialization efi: Fix efi_loaded_image_t::unload type efi/gop: Fix memory leak in __gop_query32/64() efi/gop: Return EFI_SUCCESS if a usable GOP was found efi/gop: Return EFI_NOT_FOUND if there are no usable GOPs efi/memreserve: Register reservations as 'reserved' in /proc/iomem
2019-12-09treewide: Use sizeof_field() macroPankaj Bharadiya1-1/+1
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except at places where these are defined. Later patches will remove the unused definition of FIELD_SIZEOF(). This patch is generated using following script: EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h" git grep -l -e "\bFIELD_SIZEOF\b" | while read file; do if [[ "$file" =~ $EXCLUDE_FILES ]]; then continue fi sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file; done Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com> Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: David Miller <davem@davemloft.net> # for net
2019-12-08efi/memreserve: Register reservations as 'reserved' in /proc/iomemArd Biesheuvel1-2/+26
Memory regions that are reserved using efi_mem_reserve_persistent() are recorded in a special EFI config table which survives kexec, allowing the incoming kernel to honour them as well. However, such reservations are not visible in /proc/iomem, and so the kexec tools that load the incoming kernel and its initrd into memory may overwrite these reserved regions before the incoming kernel has a chance to reserve them from further use. Address this problem by adding these reservations to /proc/iomem as they are created. Note that reservations that are inherited from a previous kernel are memblock_reserve()'d early on, so they are already visible in /proc/iomem. Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Tested-by: Bhupesh Sharma <bhsharma@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Cc: <stable@vger.kernel.org> # v5.4+ Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-2-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>