Rework the arm64 sigtramp code to be a trampoline

To help with switching to a vdso sigtramp switch to passing through the
sigcode function when entering a signal. This ensures the return address
is within the function.

Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D33690
This commit is contained in:
Andrew Turner 2021-12-29 17:40:42 +00:00
parent e031614d59
commit db3a1eec37
2 changed files with 3 additions and 3 deletions

View File

@ -624,10 +624,9 @@ sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
tf->tf_x[0] = sig;
tf->tf_x[1] = (register_t)&fp->sf_si;
tf->tf_x[2] = (register_t)&fp->sf_uc;
tf->tf_elr = (register_t)catcher;
tf->tf_x[8] = (register_t)catcher;
tf->tf_sp = (register_t)fp;
tf->tf_lr = (register_t)p->p_sysent->sv_sigcode_base;
tf->tf_elr = (register_t)p->p_sysent->sv_sigcode_base;
/* Clear the single step flag while in the signal handler */
if ((td->td_pcb->pcb_flags & PCB_SINGLE_STEP) != 0) {

View File

@ -31,6 +31,7 @@
#include <machine/asm.h>
ENTRY(sigcode)
blr x8
mov x0, sp
add x0, x0, #SF_UC