From: Yury Khrustalev <yury.khrustalev@arm.com>
Date: Mon, 28 Apr 2025 14:12:04 +0000 (+0100)
Subject: aarch64: Disable ZA state of SME in setjmp and sigsetjmp
X-Git-Tag: glibc-2.42~248
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a7f6fd976c17b82dc198290b4ab7087f35855a0e;p=thirdparty%2Fglibc.git

aarch64: Disable ZA state of SME in setjmp and sigsetjmp

Due to the nature of the ZA state, setjmp() should clear it in the
same manner as it is already done by longjmp.

Reviewed-by: Wilco Dijkstra  <Wilco.Dijkstra@arm.com>
---

diff --git a/sysdeps/aarch64/setjmp.S b/sysdeps/aarch64/setjmp.S
index d82d62c0a1..83d1e342bc 100644
--- a/sysdeps/aarch64/setjmp.S
+++ b/sysdeps/aarch64/setjmp.S
@@ -35,6 +35,29 @@ libc_hidden_def (_setjmp)
 
 ENTRY_ALIGN (__sigsetjmp, 2)
 1:
+
+#if IS_IN(libc)
+	/* Disable ZA state of SME in libc.a and libc.so, but not in ld.so.  */
+# if HAVE_AARCH64_PAC_RET
+	PACIASP
+	cfi_window_save
+# endif
+	stp	x29, x30, [sp, -16]!
+	cfi_adjust_cfa_offset (16)
+	cfi_rel_offset (x29, 0)
+	cfi_rel_offset (x30, 8)
+	mov	x29, sp
+	bl	__libc_arm_za_disable
+	ldp	x29, x30, [sp], 16
+	cfi_adjust_cfa_offset (-16)
+	cfi_restore (x29)
+	cfi_restore (x30)
+# if HAVE_AARCH64_PAC_RET
+	AUTIASP
+	cfi_window_save
+# endif
+#endif
+
 	stp	x19, x20, [x0, #JB_X19<<3]
 	stp	x21, x22, [x0, #JB_X21<<3]
 	stp	x23, x24, [x0, #JB_X23<<3]