kernel/linux.git/include/linux/efi.h, branch v4.19.310

efi: random: reduce seed size to 32 bytes

2022-11-10T16:46:55+00:00

commit 161a438d730dade2ba2b1bf8785f0759aba4ca5f upstream. We no longer need at least 64 bytes of random seed to permit the early crng init to complete. The RNG is now based on Blake2s, so reduce the EFI seed size to the Blake2s hash size, which is sufficient for our purposes. While at it, drop the READ_ONCE(), which was supposed to prevent size from being evaluated after seed was unmapped. However, this cannot actually happen, so READ_ONCE() is unnecessary here. Cc: # v4.14+ Signed-off-by: Ard Biesheuvel Reviewed-by: Jason A. Donenfeld Acked-by: Ilias Apalodimas Signed-off-by: Greg Kroah-Hartman

efi: Add missing prototype for efi_capsule_setup_info

2022-06-14T14:59:20+00:00

[ Upstream commit aa480379d8bdb33920d68acfd90f823c8af32578 ] Fixes "no previous declaration for 'efi_capsule_setup_info'" warnings under W=1. Fixes: 2959c95d510c ("efi/capsule: Add support for Quark security header") Signed-off-by: Jan Kiszka Link: https://lore.kernel.org/r/c28d3f86-dd72-27d1-e2c2-40971b8da6bd@siemens.com Signed-off-by: Ard Biesheuvel Signed-off-by: Sasha Levin

efi: provide empty efi_enter_virtual_mode implementation

2020-09-03T09:24:23+00:00

[ Upstream commit 2c547f9da0539ad1f7ef7f08c8c82036d61b011a ] When CONFIG_EFI is not enabled, we might get an undefined reference to efi_enter_virtual_mode() error, if this efi_enabled() call isn't inlined into start_kernel(). This happens in particular, if start_kernel() is annodated with __no_sanitize_address. Reported-by: kernel test robot Signed-off-by: Andrey Konovalov Signed-off-by: Andrew Morton Acked-by: Ard Biesheuvel Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Catalin Marinas Cc: Dmitry Vyukov Cc: Elena Petrova Cc: Marco Elver Cc: Vincenzo Frascino Cc: Walter Wu Link: http://lkml.kernel.org/r/6514652d3a32d3ed33d6eb5c91d0af63bf0d1a0c.1596544734.git.andreyknvl@google.com Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

efi: Make efi_rts_work accessible to efi page fault handler

2020-03-18T06:14:21+00:00

commit 9dbbedaa6171247c4c7c40b83f05b200a117c2e0 upstream. After the kernel has booted, if any accesses by firmware causes a page fault, the efi page fault handler would freeze efi_rts_wq and schedules a new process. To do this, the efi page fault handler needs efi_rts_work. Hence, make it accessible. There will be no race conditions in accessing this structure, because all the calls to efi runtime services are already serialized. Tested-by: Bhupesh Sharma Suggested-by: Matt Fleming Based-on-code-from: Ricardo Neri Signed-off-by: Sai Praneeth Prakhya Signed-off-by: Ard Biesheuvel Fixes: 3eb420e70d87 (“efi: Use a work queue to invoke EFI Runtime Services”) Signed-off-by: Wen Yang Cc: Caspar Zhang Signed-off-by: Greg Kroah-Hartman

x86/reboot, efi: Use EFI reboot for Acer TravelMate X514-51T

2019-05-16T17:41:22+00:00

[ Upstream commit 0082517fa4bce073e7cf542633439f26538a14cc ] Upon reboot, the Acer TravelMate X514-51T laptop appears to complete the shutdown process, but then it hangs in BIOS POST with a black screen. The problem is intermittent - at some points it has appeared related to Secure Boot settings or different kernel builds, but ultimately we have not been able to identify the exact conditions that trigger the issue to come and go. Besides, the EFI mode cannot be disabled in the BIOS of this model. However, after extensive testing, we observe that using the EFI reboot method reliably avoids the issue in all cases. So add a boot time quirk to use EFI reboot on such systems. Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=203119 Signed-off-by: Jian-Hong Pan Signed-off-by: Daniel Drake Cc: Ard Biesheuvel Cc: Borislav Petkov Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux@endlessm.com Link: http://lkml.kernel.org/r/20190412080152.3718-1-jian-hong@endlessm.com [ Fix !CONFIG_EFI build failure, clarify the code and the changelog a bit. ] Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

efi: Deduplicate efi_open_volume()

2018-07-22T12:13:43+00:00

There's one ARM, one x86_32 and one x86_64 version of efi_open_volume() which can be folded into a single shared version by masking their differences with the efi_call_proto() macro introduced by commit: 3552fdf29f01 ("efi: Allow bitness-agnostic protocol calls"). To be able to dereference the device_handle attribute from the efi_loaded_image_t table in an arch- and bitness-agnostic manner, introduce the efi_table_attr() macro (which already exists for x86) to arm and arm64. No functional change intended. Signed-off-by: Lukas Wunner Signed-off-by: Ard Biesheuvel Cc: Andy Shevchenko Cc: Hans de Goede Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180720014726.24031-7-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

efi: Remove the declaration of efi_late_init() as the function is unused

2018-07-15T22:43:12+00:00

The following commit: 7b0a911478c74 ("efi/x86: Move the EFI BGRT init code to early init code") ... removed the implementation and all the references to efi_late_init() but the function is still declared at include/linux/efi.h. Hence, remove the unnecessary declaration. Signed-off-by: Sai Praneeth Prakhya Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180711094040.12506-6-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

efi: Use a work queue to invoke EFI Runtime Services

2018-07-15T22:43:12+00:00

Presently, when a user process requests the kernel to execute any UEFI runtime service, the kernel temporarily switches to a separate set of page tables that describe the virtual mapping of the UEFI runtime services regions in memory. Since UEFI runtime services are typically invoked with interrupts enabled, any code that may be called during this time, will have an incorrect view of the process's address space. Although it is unusual for code running in interrupt context to make assumptions about the process context it runs in, there are cases (such as the perf subsystem taking samples) where this causes problems. So let's set up a work queue for calling UEFI runtime services, so that the actual calls are made when the work queue items are dispatched by a work queue worker running in a separate kernel thread. Such threads are not expected to have userland mappings in the first place, and so the additional mappings created for the UEFI runtime services can never clash with any. The ResetSystem() runtime service is not covered by the work queue handling, since it is not expected to return, and may be called at a time when the kernel is torn down to the point where we cannot expect work queues to still be operational. The non-blocking variants of SetVariable() and QueryVariableInfo() are also excluded: these are intended to be used from atomic context, which obviously rules out waiting for a completion to be signalled by another thread. Note that these variants are currently only used for UEFI runtime services calls that occur very early in the boot, and for ones that occur in critical conditions, e.g., to flush kernel logs to UEFI variables via efi-pstore. Suggested-by: Andy Lutomirski Signed-off-by: Sai Praneeth Prakhya [ardb: exclude ResetSystem() from the workqueue treatment merge from 2 separate patches and rewrite commit log] Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180711094040.12506-4-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

efi: Align efi_pci_io_protocol typedefs to type naming convention

2018-05-14T06:57:48+00:00

In order to use the helper macros that perform type mangling with the EFI PCI I/O protocol struct typedefs, align their Linux typenames with the convention we use for definitionns that originate in the UEFI spec, and add the trailing _t to each. Tested-by: Hans de Goede Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180504060003.19618-14-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode

2018-05-14T06:56:29+00:00

Mixed mode allows a kernel built for x86_64 to interact with 32-bit EFI firmware, but requires us to define all struct definitions carefully when it comes to pointer sizes. 'struct efi_pci_io_protocol_32' currently uses a 'void *' for the 'romimage' field, which will be interpreted as a 64-bit field on such kernels, potentially resulting in bogus memory references and subsequent crashes. Tested-by: Hans de Goede Signed-off-by: Ard Biesheuvel Cc: Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180504060003.19618-13-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar