The pseudocode ResetSVEState() does:
FPSR = ZeroExtend(0x0800009f<31:0>, 64);
but QEMU's arm_reset_sve_state() called vfp_set_fpcr() by accident.
Before the advent of FEAT_AFP, this was only setting a collection of
RES0 bits, which vfp_set_fpsr() would then ignore, so the only effect
was that we didn't actually set the FPSR the way we are supposed to
do. Once FEAT_AFP is implemented, setting the bottom bits of FPSR
will change the floating point behaviour.
Call vfp_set_fpsr(), as we ought to.
(Note for stable backports: commit 7f2a01e736 moved this function
from sme_helper.c to helper.c, but it had the same bug before the
move too.)
Cc: qemu-stable@nongnu.org
Fixes: f84734b874 ("target/arm: Implement SMSTART, SMSTOP")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20250124162836.2332150-4-peter.maydell@linaro.org
(cherry picked from commit 1edc3d43f2)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(it is in sme_helper.c in 7.2, not in helper.c)
3559e90146