50 #include <asm/text-patching.h>
65 #include <asm/insn-eval.h>
73 #include <asm/processor-flags.h>
119 		*len = addr - start;  in decode_bug()
150 	*len = addr - start;  in decode_bug()
177 		tsk->thread.error_code = error_code;  in do_trap_no_signal()
178 		tsk->thread.trap_nr = trapnr;  in do_trap_no_signal()
194 	tsk->thread.error_code = error_code;  in do_trap_no_signal()
195 	tsk->thread.trap_nr = trapnr;  in do_trap_no_signal()
197 	return -1;  in do_trap_no_signal()
207 			tsk->comm, task_pid_nr(tsk), type, desc,  in show_signal()
208 			regs->ip, regs->sp, error_code);  in show_signal()
209 		print_vma_addr(KERN_CONT " in ", regs->ip);  in show_signal()
249  * This address is usually regs->ip, but when an uprobe moved the code out
250  * of line then regs->ip points to the XOL code which would confuse
252  * a trap happened in XOL code then uprobe maps regs->ip back to the
287 	ud_type = decode_bug(regs->ip, &ud_imm, &ud_len);  in handle_bug()
305 	if (regs->flags & X86_EFLAGS_IF)  in handle_bug()
310 		if (report_bug(regs->ip, regs) == BUG_TRAP_TYPE_WARN ||  in handle_bug()
312 			regs->ip += ud_len;  in handle_bug()
321 				(void *)regs->ip);  in handle_bug()
329 	if (regs->flags & X86_EFLAGS_IF)  in handle_bug()
406 	const char *name = stack_type_name(info->type);  in handle_stack_overflow()
409 	       name, (void *)fault_address, info->begin, info->end);  in handle_stack_overflow()
442  * while the stack is read-only are, in fact, recoverable.
466 	 * If IRET takes a non-IST fault on the espfix64 stack, then we  in DEFINE_IDTENTRY_DF()
479 	if (((long)regs->sp >> P4D_SHIFT) == ESPFIX_PGD_ENTRY &&  in DEFINE_IDTENTRY_DF()
480 		regs->cs == __KERNEL_CS &&  in DEFINE_IDTENTRY_DF()
481 		regs->ip == (unsigned long)native_irq_return_iret)  in DEFINE_IDTENTRY_DF()
483 		struct pt_regs *gpregs = (struct pt_regs *)this_cpu_read(cpu_tss_rw.x86_tss.sp0) - 1;  in DEFINE_IDTENTRY_DF()
484 		unsigned long *p = (unsigned long *)regs->sp;  in DEFINE_IDTENTRY_DF()
487 		 * regs->sp points to the failing IRET frame on the  in DEFINE_IDTENTRY_DF()
489 		 * in gpregs->ss through gpregs->ip.  in DEFINE_IDTENTRY_DF()
492 		gpregs->ip	= p[0];  in DEFINE_IDTENTRY_DF()
493 		gpregs->cs	= p[1];  in DEFINE_IDTENTRY_DF()
494 		gpregs->flags	= p[2];  in DEFINE_IDTENTRY_DF()
495 		gpregs->sp	= p[3];  in DEFINE_IDTENTRY_DF()
496 		gpregs->ss	= p[4];  in DEFINE_IDTENTRY_DF()
497 		gpregs->orig_ax = 0;  /* Missing (lost) #GP error code */  in DEFINE_IDTENTRY_DF()
510 		regs->ip = (unsigned long)asm_exc_general_protection;  in DEFINE_IDTENTRY_DF()
511 		regs->sp = (unsigned long)&gpregs->orig_ax;  in DEFINE_IDTENTRY_DF()
521 	tsk->thread.error_code = error_code;  in DEFINE_IDTENTRY_DF()
522 	tsk->thread.trap_nr = X86_TRAP_DF;  in DEFINE_IDTENTRY_DF()
528 	 * take any non-IST exception while too close to the bottom of  in DEFINE_IDTENTRY_DF()
532 	 * According to the SDM (footnote in 6.15 under "Interrupt 14 -  in DEFINE_IDTENTRY_DF()
533 	 * Page-Fault Exception (#PF):  in DEFINE_IDTENTRY_DF()
597  * out whether any part of the access to that address was non-canonical.
606 	if (copy_from_kernel_nofault(insn_buf, (void *)regs->ip,  in get_kernel_gp_address()
615 	if (*addr == -1UL)  in get_kernel_gp_address()
621 	 *  - the operand is not in the kernel half  in get_kernel_gp_address()
622 	 *  - the last byte of the operand is not in the user canonical half  in get_kernel_gp_address()
625 	    *addr + insn.opnd_bytes - 1 > __VIRTUAL_MASK)  in get_kernel_gp_address()
636 	struct thread_struct *t = &current->thread;  in fixup_iopl_exception()
640 	if (!IS_ENABLED(CONFIG_X86_IOPL_IOPERM) || t->iopl_emul != 3)  in fixup_iopl_exception()
652 	if (!t->iopl_warn && printk_ratelimit()) {  in fixup_iopl_exception()
654 		       current->comm, task_pid_nr(current), ip);  in fixup_iopl_exception()
657 		t->iopl_warn = 1;  in fixup_iopl_exception()
660 	regs->ip += 1;  in fixup_iopl_exception()
679 	 * in *before* interrupts are re-enabled.  in try_fixup_enqcmd_gp()
694 	if (!mm_valid_pasid(current->mm))  in try_fixup_enqcmd_gp()
697 	pasid = current->mm->pasid;  in try_fixup_enqcmd_gp()
703 	if (current->pasid_activated)  in try_fixup_enqcmd_gp()
707 	current->pasid_activated = 1;  in try_fixup_enqcmd_gp()
722 	current->thread.error_code = error_code;  in gp_try_fixup_and_notify()
723 	current->thread.trap_nr = trapnr;  in gp_try_fixup_and_notify()
727 	 * from kprobe_running(), we have to be non-preemptible.  in gp_try_fixup_and_notify()
739 	current->thread.error_code = error_code;  in gp_user_force_sig_segv()
740 	current->thread.trap_nr = trapnr;  in gp_user_force_sig_segv()
783 		snprintf(desc, sizeof(desc), "segment-related " GPFSTR);  in DEFINE_IDTENTRY_ERRORCODE()
789 			 (hint == GP_NON_CANONICAL) ? "probably for non-canonical address"  in DEFINE_IDTENTRY_ERRORCODE()
794 	 * KASAN is interested only in the non-canonical case, clear it  in DEFINE_IDTENTRY_ERRORCODE()
872  * Help handler running on a per-cpu (IST or entry trampoline) stack
878 	struct pt_regs *regs = (struct pt_regs *)this_cpu_read(pcpu_hot.top_of_stack) - 1;  in sync_regs()
892 	 * In the SYSCALL entry path the RSP value comes from user-space - don't  in vc_switch_off_ist()
903 	 * use the fall-back stack instead in this case.  in vc_switch_off_ist()
905 	sp    = regs->sp;  in vc_switch_off_ist()
914 	 * Found a safe stack - switch to it as if the entry didn't happen via  in vc_switch_off_ist()
918 	sp = ALIGN_DOWN(sp, 8) - sizeof(*regs_ret);  in vc_switch_off_ist()
939 	new_stack = (struct pt_regs *)__this_cpu_read(cpu_tss_rw.x86_tss.sp0) - 1;  in fixup_bad_iret()
942 	__memcpy(&tmp.ip, (void *)bad_regs->sp, 5*8);  in fixup_bad_iret()
959 	 * code that can be single-stepped in the SYSENTER entry path, then  in is_sysenter_singlestep()
960 	 * assume that this is a useless single-step trap due to SYSENTER  in is_sysenter_singlestep()
966 	return (regs->ip - (unsigned long)__begin_SYSENTER_singlestep_region) <  in is_sysenter_singlestep()
967 		(unsigned long)__end_SYSENTER_singlestep_region -  in is_sysenter_singlestep()
970 	return (regs->ip - (unsigned long)entry_SYSENTER_compat) <  in is_sysenter_singlestep()
971 		(unsigned long)__end_entry_SYSENTER_compat -  in is_sysenter_singlestep()
985 	 *   Certain debug exceptions may clear bits 0-3. The remaining  in debug_read_clear_dr6()
1001  * Our handling of the processor debug registers is non-trivial.
1005  * only set watchpoints on userspace addresses. Therefore the in-kernel
1029 	 * consumed - hw_breakpoint_handler(), single_stop_cont().  in notify_debug()
1032 	 * for signals - ptrace_triggered(), kgdb_hw_overflow_handler().  in notify_debug()
1068 		 * it for userspace, but we just took a kernel #DB, so re-set  in exc_debug_kernel()
1095 	 * The kernel doesn't use TF single-step outside of:  in exc_debug_kernel()
1097 	 *  - Kprobes, consumed through kprobe_debug_handler()  in exc_debug_kernel()
1098 	 *  - KGDB, consumed through notify_debug()  in exc_debug_kernel()
1106 		regs->flags &= ~X86_EFLAGS_TF;  in exc_debug_kernel()
1144 	current->thread.virtual_dr6 = (dr6 & DR_STEP);  in exc_debug_user()
1175 	/* Add the virtual_dr6 bits for signals. */  in exc_debug_user()
1176 	dr6 |= current->thread.virtual_dr6;  in exc_debug_user()
1220 	struct fpu *fpu = &task->thread.fpu;  in math_error()
1231 		task->thread.error_code = 0;  in math_error()
1232 		task->thread.trap_nr = trapnr;  in math_error()
1246 	task->thread.trap_nr	= trapnr;  in math_error()
1247 	task->thread.error_code = 0;  in math_error()
1285 	 * PROBLEM: If the APIC subsystem is configured in mixed mode with  in DEFINE_IDTENTRY()
1326 	case -EPERM:  in handle_xfd_event()
1329 	case -EFAULT:  in handle_xfd_event()
1366 		 * to kill the task than getting stuck in a never-ending  in DEFINE_IDTENTRY()
1404  * never generated on accesses to normal, TD-private memory that has been
1411  * IRET will re-enable NMIs and nested NMI will corrupt the NMI stack.
1414  * the NMI entry code. Entry code paths do not access TD-shared memory,
1428  * the interrupt-disabled region before TDGETVEINFO, a #DF (fault
1441 	 * NMIs/Machine-checks/Interrupts will be in a disabled state  in DEFINE_IDTENTRY()
1479 	/* Init GHCB memory pages when running as an SEV-ES guest */  in trap_init()