git: d2e48ad87d3e - stable/13 - arm64: Make sure COMPAT_FREEBSD32 handles thumb entry point.

[Olivier Houchard]

The branch stable/13 has been updated by cognet:

URL: https://cgit.FreeBSD.org/src/commit/?id=d2e48ad87d3e0f63f4ac73c524fb18afce4a2d53

commit d2e48ad87d3e0f63f4ac73c524fb18afce4a2d53
Author:     Olivier Houchard <cognet at FreeBSD.org>
AuthorDate: 2021-06-30 12:50:47 +0000
Commit:     Olivier Houchard <cognet at FreeBSD.org>
CommitDate: 2021-07-07 20:22:18 +0000

    arm64: Make sure COMPAT_FREEBSD32 handles thumb entry point.
    
    If the entry point for the binary executed is a thumb 2 entry point, make
    sure we set the PSR_T bit, or the CPU will interpret it as arm32 code and
    bad things will happen.
    
    PR: 256899
    MFC after: 1 week
    
    (cherry picked from commit 712c060c94fd447c91b0e6218c12a431206b487a)
    Signed-off-by: Olivier Houchard <cognet at FreeBSD.org>
---
 sys/arm64/arm64/elf32_machdep.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/arm64/arm64/elf32_machdep.c b/sys/arm64/arm64/elf32_machdep.c
index b9669616e1dd..6c98f7c839ca 100644
--- a/sys/arm64/arm64/elf32_machdep.c
+++ b/sys/arm64/arm64/elf32_machdep.c
@@ -255,6 +255,8 @@ freebsd32_setregs(struct thread *td, struct image_params *imgp,
 	tf->tf_x[14] = imgp->entry_addr;
 	tf->tf_elr = imgp->entry_addr;
 	tf->tf_spsr = PSR_M_32;
+	if ((uint32_t)imgp->entry_addr & 1)
+		tf->tf_spsr |= PSR_T;
 
 #ifdef VFP
 	vfp_reset_state(td, pcb);