From 9d30e5cf9687559d942514c780332d53b0617f0b Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Fri, 17 Dec 2021 17:14:59 +0000 Subject: aarch64: Add setcontext support for SME For the ZA lazy saving scheme to work, setcontext has to call __libc_arm_za_disable. Also fixes swapcontext which uses setcontext internally. Reviewed-by: Adhemerval Zanella --- sysdeps/unix/sysv/linux/aarch64/setcontext.S | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'sysdeps') diff --git a/sysdeps/unix/sysv/linux/aarch64/setcontext.S b/sysdeps/unix/sysv/linux/aarch64/setcontext.S index 699c31189f..ba659438c5 100644 --- a/sysdeps/unix/sysv/linux/aarch64/setcontext.S +++ b/sysdeps/unix/sysv/linux/aarch64/setcontext.S @@ -49,6 +49,25 @@ ENTRY (__setcontext) cbz x0, 1f b C_SYMBOL_NAME (__syscall_error) 1: + /* Disable ZA of SME. */ +#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 /* Restore the general purpose registers. */ mov x0, x9 cfi_def_cfa (x0, 0) -- cgit 1.4.1