Date: Tue, 19 Sep 2023 15:59:31 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 273929] AArch64 machine-dependent code clobbers X0 in SIGTRAP from capsicum violations Message-ID: <bug-273929-227-Dd1WVLupLh@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-273929-227@https.bugs.freebsd.org/bugzilla/> References: <bug-273929-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D273929 --- 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 c= ode needs to care. The calling convention for the syscall says that x9 is allo= wed 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. --=20 You are receiving this mail because: You are the assignee for the bug.=
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