floating point exceptions - but some (actually all currently know ones)
do not implement sending traps when these exceptions are raised.
Pointed out by Peter Maydell.
If we write a byte character into a pointer, a compiler can emit a
read-modify-write operation, especially when a CPU cannot access directly
a character wide address.
In this scenario calling mmap(2) with PROT_WRITE, without PROT_READ will
emit unexpected trap.
There are two possible workarounds for this issue:
- write register wide memory without rmw sequence,
- mark the region with additional protection PROT_READ
Both work for NetBSD/alpha.
Go for the latter as perhaps more safe for dump compilers emitting rmw
sequences.
Investigated by <martin>
These crash signals are crucial for proper handling of abnormal conditions
in a program. The additional purpose of these tests it to assure the proper
handling of these signals for the coming ptrace(2)-related changes in the
signal routing code.
Add a stub for ILL scenarios.
All tests pass (on amd64).
The shell ATF script contains duplicated code. There should be a way to
deduplicate it, without rewrite to C.
Sponsored by <The NetBSD Foundation>
There are at least four types of SIGTRAP events:
- software/hardware single step (trace trap)
- software breakpoint
- hardware breakpoint/watchpoint
- kernel event (exec, fork, vfork, vfork-done, lwp-create, lwp-exit)
A program can execute software breakpoint without the context of being
traced and this is a regular crash signal emitting SIGTRAP (TRAP_BRKPT).
Rename original trap_* tests (trap_simple, trap_handle, trap_mask,
trap_handle_recurse and trap_ignore) to segv_* tests and restrict them for
SIGSEGV.
Add new tests: trap_* testing the same scenarios as segv_ ones, however
verifying the software breakpoint trap (SIGTRAP).
Keep the original name of h_segv.c, and extend it for software breakpoint
events.
The purpose of these tests is to verify SIGTRAP kernel paths without the
ptrace(2) context.
All tests pass.
Sponsored by <The NetBSD Foundation>
kamil