From 9f23a5d2f6b01c2ab91d791109731a0d87ec2239 Mon Sep 17 00:00:00 2001 From: Clément Léger Date: Wed, 4 Oct 2023 17:14:05 +0200 Subject: riscv: add support for PR_SET_UNALIGN and PR_GET_UNALIGN MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Now that trap support is ready to handle misalignment errors in S-mode, allow the user to control the behavior of misaligned accesses using prctl(PR_SET_UNALIGN). Add an align_ctl flag in thread_struct which will be used to determine if we should SIGBUS the process or not on such fault. Signed-off-by: Clément Léger Reviewed-by: Björn Töpel Link: https://lore.kernel.org/r/20231004151405.521596-9-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/processor.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/riscv/include/asm/processor.h') diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 3e23e1786d05..adbe520d07c5 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -8,6 +8,7 @@ #include #include +#include #include @@ -82,6 +83,7 @@ struct thread_struct { unsigned long bad_cause; unsigned long vstate_ctrl; struct __riscv_v_ext_state vstate; + unsigned long align_ctl; }; /* Whitelist the fstate from the task_struct for hardened usercopy */ @@ -94,6 +96,7 @@ static inline void arch_thread_struct_whitelist(unsigned long *offset, #define INIT_THREAD { \ .sp = sizeof(init_stack) + (long)&init_stack, \ + .align_ctl = PR_UNALIGN_NOPRINT, \ } #define task_pt_regs(tsk) \ @@ -134,6 +137,12 @@ extern long riscv_v_vstate_ctrl_set_current(unsigned long arg); extern long riscv_v_vstate_ctrl_get_current(void); #endif /* CONFIG_RISCV_ISA_V */ +extern int get_unalign_ctl(struct task_struct *tsk, unsigned long addr); +extern int set_unalign_ctl(struct task_struct *tsk, unsigned int val); + +#define GET_UNALIGN_CTL(tsk, addr) get_unalign_ctl((tsk), (addr)) +#define SET_UNALIGN_CTL(tsk, val) set_unalign_ctl((tsk), (val)) + #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_PROCESSOR_H */ -- cgit v1.2.3-58-ga151