1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
6  * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
16 #include <as-layout.h>
46 	/* enable signals if sig isn't IRQ signal */  in sig_handler_common()
56  * These are the asynchronous signals.  SIGPROF is excluded because we want to
57  * be able to profile all of UML, not just the non-critical sections.  If
58  * profiling is not thread-safe, then that is not my problem.  We can disable
91 		 * In TT_MODE_EXTERNAL, need to still call time-travel  in sig_handler()
94 		 * Note we won't get here if signals are hard-blocked  in sig_handler()
95 		 * (which is handled above), in that case the hard-  in sig_handler()
192 	mcontext_t *mc = &uc->uc_mcontext;  in hard_handler()
216 			sig--;  in hard_handler()
222 		 * Again, pending comes back with a mask of signals  in hard_handler()
224 		 * is non-zero, we just go back, set up the stack  in hard_handler()
240 	/* block irq ones */  in set_handler()
250 		flags |= SA_RESTART; /* if it's an irq signal */  in set_handler()
255 		panic("sigaction failed - errno = %d\n", errno);  in set_handler()
260 		panic("sigprocmask failed - errno = %d\n", errno);  in set_handler()
275 		return -errno;  in change_sig()
284 	 * This must return with signals disabled, so this barrier  in block_signals()
305 	 * We loop because the IRQ handler returns with interrupts off.  So,  in unblock_signals()
306 	 * interrupts may have arrived and we need to re-enable them and  in unblock_signals()
311 		 * Save and reset save_pending after enabling signals.  This  in unblock_signals()
326 		 * We have pending interrupts, so disable signals, as the  in unblock_signals()
331 		 * pending signals will mess up the tracing state.  in unblock_signals()
357 		/* Re-enable signals and trace that we're doing so. */  in unblock_signals()
397 	 * it isn't a read-modify-write with a signal  in mark_sigio_pending()
402 	 * time-travel=ext simulation mode, in which case  in mark_sigio_pending()
421 		panic("unblocking signals while not blocked");  in unblock_signals_hard()
423 	if (--signals_blocked)  in unblock_signals_hard()
438 	 * pending signals, we can get out of the inner call with the real  in unblock_signals_hard()
441 	 * the outermost call - 'unblocking' serves as an ownership for the  in unblock_signals_hard()
450 			/* signals are enabled so we can touch this */  in unblock_signals_hard()
460 			 * we need to run time-travel handlers even  in unblock_signals_hard()
469 		 * the decrement, not during a read-modify-write:  in unblock_signals_hard()
470 		 *  - If it happens before, it can increment it and we'll  in unblock_signals_hard()
472 		 *  - If it happens after it'll see 0 for both signals_blocked  in unblock_signals_hard()