kernel/linux.git/arch/riscv/include/asm/efi.h, branch v6.19.5

Merge patch series "riscv: Introduce KASLR"

2023-09-08T18:25:13+00:00

Alexandre Ghiti says: The following KASLR implementation allows to randomize the kernel mapping: - virtually: we expect the bootloader to provide a seed in the device-tree - physically: only implemented in the EFI stub, it relies on the firmware to provide a seed using EFI_RNG_PROTOCOL. arm64 has a similar implementation hence the patch 3 factorizes KASLR related functions for riscv to take advantage. The new virtual kernel location is limited by the early page table that only has one PUD and with the PMD alignment constraint, the kernel can only take < 512 positions. * b4-shazam-merge: riscv: libstub: Implement KASLR by using generic functions libstub: Fix compilation warning for rv32 arm64: libstub: Move KASLR handling functions to kaslr.c riscv: Dump out kernel offset information on panic riscv: Introduce virtual kernel mapping KASLR Link: https://lore.kernel.org/r/20230722123850.634544-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt

riscv: libstub: Implement KASLR by using generic functions

2023-09-06T02:49:31+00:00

We can now use arm64 functions to handle the move of the kernel physical mapping: if KASLR is enabled, we will try to get a random seed from the firmware, if not possible, the kernel will be moved to a location that suits its alignment constraints. Signed-off-by: Alexandre Ghiti Tested-by: Conor Dooley Tested-by: Song Shuai Reviewed-by: Sami Tolvanen Tested-by: Sami Tolvanen Link: https://lore.kernel.org/r/20230722123850.634544-6-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt

efi/riscv: Move EFI runtime call setup/teardown helpers out of line

2023-08-21T15:59:25+00:00

Only the arch_efi_call_virt() macro that some architectures override needs to be a macro, given that it is variadic and encapsulates calls via function pointers that have different prototypes. The associated setup and teardown code are not special in this regard, and don't need to be instantiated at each call site. So turn them into ordinary C functions and move them out of line. Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Signed-off-by: Ard Biesheuvel

efi: Discover BTI support in runtime services regions

2023-02-04T08:19:02+00:00

Add the generic plumbing to detect whether or not the runtime code regions were constructed with BTI/IBT landing pads by the firmware, permitting the OS to enable enforcement when mapping these regions into the OS's address space. Signed-off-by: Ard Biesheuvel Reviewed-by: Kees Cook

Merge tag 'v6.1-rc8' into efi/next

2022-12-07T18:08:57+00:00

Linux 6.1-rc8

riscv: Sync efi page table's kernel mappings before switching

2022-11-29T00:36:34+00:00

The EFI page table is initially created as a copy of the kernel page table. With VMAP_STACK enabled, kernel stacks are allocated in the vmalloc area: if the stack is allocated in a new PGD (one that was not present at the moment of the efi page table creation or not synced in a previous vmalloc fault), the kernel will take a trap when switching to the efi page table when the vmalloc kernel stack is accessed, resulting in a kernel panic. Fix that by updating the efi kernel mappings before switching to the efi page table. Signed-off-by: Alexandre Ghiti Fixes: b91540d52a08 ("RISC-V: Add EFI runtime services") Tested-by: Emil Renner Berthing Reviewed-by: Atish Patra Link: https://lore.kernel.org/r/20221121133303.1782246-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt

efi/riscv: libstub: Split off kernel image relocation for builtin stub

2022-11-09T11:42:03+00:00

The RISC-V build of the EFI stub is part of the core kernel image, and therefore accesses section markers directly when it needs to figure out the size of the various section. The zboot decompressor does not have access to those symbols, but doesn't really need that either. So let's move handle_kernel_image() into a separate file (or rather, move everything else into a separate file) so that the zboot build does not pull in unused code that links to symbols that it does not define. Signed-off-by: Ard Biesheuvel

efi: libstub: Factor out min alignment and preferred kernel load address

2022-11-09T11:42:03+00:00

Factor out the expressions that describe the preferred placement of the loaded image as well as the minimum alignment so we can reuse them in the decompressor. Signed-off-by: Ard Biesheuvel

efi: libstub: Move screen_info handling to common code

2022-11-09T11:42:02+00:00

Currently, arm64, RISC-V and LoongArch rely on the fact that struct screen_info can be accessed directly, due to the fact that the EFI stub and the core kernel are part of the same image. This will change after a future patch, so let's ensure that the screen_info handling is able to deal with this, by adopting the arm32 approach of passing it as a configuration table. While at it, switch to ACPI reclaim memory to hold the screen_info data, which is more appropriate for this kind of allocation. Signed-off-by: Ard Biesheuvel

efi: Simplify arch_efi_call_virt() macro

2022-06-28T18:13:09+00:00

Currently, the arch_efi_call_virt() assumes all users of it will have defined a type 'efi_##f##_t' to make use of it. Simplify the arch_efi_call_virt() macro by eliminating the explicit need for efi_##f##_t type for every user of this macro. Signed-off-by: Sudeep Holla Acked-by: Russell King (Oracle) [ardb: apply Sudeep's ARM fix to i686, Loongarch and RISC-V too] Signed-off-by: Ard Biesheuvel