FEAT_LSFE is optional from v9.5, it adds new instructions for atomic memory operations with floating point values. We have no immediate use for it in kernel, provide a hwcap so userspace can discover it and allow the ID register field to be exposed to KVM guests.
Signed-off-by: Mark Brown broonie@kernel.org --- Changes in v4: - Rebase onto arm64/for-next/cpufeature, note that both patches have build dependencies on this. - Drop unneeded cc clobber in hwcap. - Use STRFADD as the instruction probed in hwcap. - Link to v3: https://lore.kernel.org/r/20250818-arm64-lsfe-v3-0-af6f4d66eb39@kernel.org
Changes in v3: - Rebase onto v6.17-rc1. - Link to v2: https://lore.kernel.org/r/20250703-arm64-lsfe-v2-0-eced80999cb4@kernel.org
Changes in v2: - Fix result of vi dropping in hwcap test. - Link to v1: https://lore.kernel.org/r/20250627-arm64-lsfe-v1-0-68351c4bf741@kernel.org
--- Mark Brown (2): KVM: arm64: Expose FEAT_LSFE to guests kselftest/arm64: Add lsfe to the hwcaps test
arch/arm64/kvm/sys_regs.c | 4 +++- tools/testing/selftests/arm64/abi/hwcap.c | 21 +++++++++++++++++++++ 2 files changed, 24 insertions(+), 1 deletion(-) --- base-commit: 220928e52cb03d223b3acad3888baf0687486d21 change-id: 20250625-arm64-lsfe-0810cf98adc2
Best regards, -- Mark Brown broonie@kernel.org