[Bug 273929] AArch64 machine-dependent code clobbers X0 in SIGTRAP from capsicum violations

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=273929

--- Comment #8 from David Chisnall <theraven@FreeBSD.org> ---
(In reply to Kyle Evans from comment #7)
I think if syscall entry copies x0 of x9 in the trap frame, then no other code
needs to care.  The calling convention for the syscall says that x9 is allowed
to be clobbered, so nothing on the caller side may rely on it being stable.  If
there isn't a signal, it's just a callee-save register that changed as
permitted.  If there is a signal, the signal handler can pick it up.

-- 
You are receiving this mail because:
You are the assignee for the bug.