On 7/26/21 4:59 AM, Andrew Jones wrote:
+SVE User-mode Default Vector Length Property
+--------------------------------------------
+
+For qemu-aarch64, the cpu property `sve-default-vector-length=N` is
+defined to mirror the Linux kernel parameter file
+`/proc/sys/abi/sve_default_vector_length`. The default length, `N`,
+is in units of bytes and must be between 16 and 8192.
Hmm. If a user inputs anything greater than 256, then won't it get
silently reduced to 256?
Yes.
+If not specified, the default vector length is 64.
+
+If the default length is larger than the maximum vector length enabled
+with `sve<N>` properties, the actual vector length will be reduced.
Here it's pointed out that the default may be reduced, but it implies that
that only happens if an sve<N> property is also given. Won't users wonder
why they're only getting vectors that are 256 bytes large even when they
ask for more?
I guess adding that 256 is the maximum length supported by qemu should be
sufficient?
r~
