1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_SIGHANDLING_H 3 #define _ASM_X86_SIGHANDLING_H 4 5 #include <linux/compiler.h> 6 #include <linux/ptrace.h> 7 #include <linux/signal.h> 8 9 #include <asm/processor-flags.h> 10 11 #define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \ 12 X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \ 13 X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \ 14 X86_EFLAGS_CF | X86_EFLAGS_RF) 15 16 void signal_fault(struct pt_regs *regs, void __user *frame, char *where); 17 18 void __user * 19 get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size, 20 void __user **fpstate); 21 22 int ia32_setup_frame(struct ksignal *ksig, struct pt_regs *regs); 23 int ia32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs); 24 int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs); 25 int x32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs); 26 27 /* 28 * To prevent immediate repeat of single step trap on return from SIGTRAP 29 * handler if the trap flag (TF) is set without an external debugger attached, 30 * clear the software event flag in the augmented SS, ensuring no single-step 31 * trap is pending upon ERETU completion. 32 * 33 * Note, this function should be called in sigreturn() before the original 34 * state is restored to make sure the TF is read from the entry frame. 35 */ 36 static __always_inline void prevent_single_step_upon_eretu(struct pt_regs *regs) 37 { 38 /* 39 * If the trap flag (TF) is set, i.e., the sigreturn() SYSCALL instruction 40 * is being single-stepped, do not clear the software event flag in the 41 * augmented SS, thus a debugger won't skip over the following instruction. 42 */ 43 #ifdef CONFIG_X86_FRED 44 if (!(regs->flags & X86_EFLAGS_TF)) 45 regs->fred_ss.swevent = 0; 46 #endif 47 } 48 49 #endif /* _ASM_X86_SIGHANDLING_H */ 50