When a crashkernel is launched on RISC-V, the entry to purgatory is
done by trapping via the stvec CSR. From riscv_kexec_norelocate():
| ...
| /*
| * Switch to physical addressing
| * This will also trigger a jump to CSR_STVEC
| * which in this case is the address of the new
| * kernel.
| */
| csrw CSR_STVEC, a2
| csrw CSR_SATP, zero
stvec requires that the address is 4B aligned, which was not the case,
e.g.:
| Loaded purgatory at 0xffffc000
| kexec_file: kexec_file_load: type:1, start:0xffffd232 head:0x4 flags:0x6
The address 0xffffd232 not 4B aligned.
Correct by adding proper function alignment.
With this change, crashkernels loaded with kexec-file will be able to
properly enter the purgatory.
Fixes: 736e30af58 ("RISC-V: Add purgatory")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250328085313.1193815-1-bjorn@kernel.org
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
When alignment handling is delegated to the kernel, everything must be
word-aligned in purgatory, since the trap handler is then set to the
kexec one. Without the alignment, hitting the exception would
ultimately crash. On other occasions, the kernel's handler would take
care of exceptions.
This has been tested on a JH7110 SoC with oreboot and its SBI delegating
unaligned access exceptions and the kernel configured to handle them.
Fixes: 736e30af58 ("RISC-V: Add purgatory")
Signed-off-by: Daniel Maslowski <cyrevolt@gmail.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240719170437.247457-1-cyrevolt@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
ENTRY()/END()/WEAK() macros are deprecated and we should make use of the
new SYM_*() macros [1] for better annotation of symbols. Replace the
deprecated ones with the new ones and fix wrong usage of END()/ENDPROC()
to correctly describe the symbols.
[1] https://docs.kernel.org/core-api/asm-annotations.html
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20231024132655.730417-3-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This patch adds purgatory, the name and concept have been taken
from kexec-tools. Purgatory runs between two kernels, and do
verify sha256 hash to ensure the kernel to jump to is fine and
has not been corrupted after loading. Makefile is modified based
on x86 platform.
Signed-off-by: Li Zhengyu <lizhengyu3@huawei.com>
Link: https://lore.kernel.org/r/20220408100914.150110-6-lizhengyu3@huawei.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
