The branch main has been updated by andrew:
URL:
https://cgit.FreeBSD.org/src/commit/?id=db3a1eec371f8c2c060805dbe93eaf76aa92c5f8
commit db3a1eec371f8c2c060805dbe93eaf76aa92c5f8
Author: Andrew Turner <and...@freebsd.org>
AuthorDate: 2021-12-29 17:40:42 +0000
Commit: Andrew Turner <and...@freebsd.org>
CommitDate: 2022-03-07 10:03:07 +0000
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
---
sys/arm64/arm64/exec_machdep.c | 5 ++---
sys/arm64/arm64/sigtramp.S | 1 +
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/sys/arm64/arm64/exec_machdep.c b/sys/arm64/arm64/exec_machdep.c
index b60909c95945..c8e333f330cc 100644
--- a/sys/arm64/arm64/exec_machdep.c
+++ b/sys/arm64/arm64/exec_machdep.c
@@ -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) {
diff --git a/sys/arm64/arm64/sigtramp.S b/sys/arm64/arm64/sigtramp.S
index b06ec6fa109c..a9ad10da766c 100644
--- a/sys/arm64/arm64/sigtramp.S
+++ b/sys/arm64/arm64/sigtramp.S
@@ -31,6 +31,7 @@
#include <machine/asm.h>
ENTRY(sigcode)
+ blr x8
mov x0, sp
add x0, x0, #SF_UC
