diff options
| author | Clément Léger <cleger@rivosinc.com> | 2023-10-04 17:13:59 +0200 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-11-01 08:34:53 -0700 |
| commit | 7c83232161f609bbc452a1255f823f41afc411dd (patch) | |
| tree | 8c03bf915d29719e12c25ba4ec0e805b3c5e10de /arch/riscv/Kconfig | |
| parent | f19c3b4239f5bfb69aacbaf75d4277c095e7aa7d (diff) | |
| download | lwn-7c83232161f609bbc452a1255f823f41afc411dd.tar.gz lwn-7c83232161f609bbc452a1255f823f41afc411dd.zip | |
riscv: add support for misaligned trap handling in S-mode
Misalignment trap handling is only supported for M-mode and uses direct
accesses to user memory. In S-mode, when handling usermode fault, this
requires to use the get_user()/put_user() accessors. Implement
load_u8(), store_u8() and get_insn() using these accessors for
userspace and direct text access for kernel.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-3-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/Kconfig')
| -rw-r--r-- | arch/riscv/Kconfig | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index d607ab0f7c6d..6e167358a897 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -636,6 +636,14 @@ config THREAD_SIZE_ORDER Specify the Pages of thread stack size (from 4KB to 64KB), which also affects irq stack size, which is equal to thread stack size. +config RISCV_MISALIGNED + bool "Support misaligned load/store traps for kernel and userspace" + default y + help + Say Y here if you want the kernel to embed support for misaligned + load/store for both kernel and userspace. When disable, misaligned + accesses will generate SIGBUS in userspace and panic in kernel. + endmenu # "Platform type" menu "Kernel features" |