diff options
Diffstat (limited to 'arch/x86/include/asm/sighandling.h')
| -rw-r--r-- | arch/x86/include/asm/sighandling.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86/include/asm/sighandling.h b/arch/x86/include/asm/sighandling.h index 65e667279e0f..8727c7e21dd1 100644 --- a/arch/x86/include/asm/sighandling.h +++ b/arch/x86/include/asm/sighandling.h @@ -15,4 +15,35 @@ void signal_fault(struct pt_regs *regs, void __user *frame, char *where); +void __user * +get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size, + void __user **fpstate); + +int ia32_setup_frame(struct ksignal *ksig, struct pt_regs *regs); +int ia32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs); +int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs); +int x32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs); + +/* + * To prevent immediate repeat of single step trap on return from SIGTRAP + * handler if the trap flag (TF) is set without an external debugger attached, + * clear the software event flag in the augmented SS, ensuring no single-step + * trap is pending upon ERETU completion. + * + * Note, this function should be called in sigreturn() before the original + * state is restored to make sure the TF is read from the entry frame. + */ +static __always_inline void prevent_single_step_upon_eretu(struct pt_regs *regs) +{ + /* + * If the trap flag (TF) is set, i.e., the sigreturn() SYSCALL instruction + * is being single-stepped, do not clear the software event flag in the + * augmented SS, thus a debugger won't skip over the following instruction. + */ +#ifdef CONFIG_X86_FRED + if (!(regs->flags & X86_EFLAGS_TF)) + regs->fred_ss.swevent = 0; +#endif +} + #endif /* _ASM_X86_SIGHANDLING_H */ |