From: Mark Rutland <mark.rutland@xxxxxxx> commit 81235ae0c846e1fb46a2c6fe9283fe2b2b24f7dc upstream. Although support for SME was merged in v5.19, we've since uncovered a number of issues with the implementation, including issues which might corrupt the FPSIMD/SVE/SME state of arbitrary tasks. While there are patches to address some of these issues, ongoing review has highlighted additional functional problems, and more time is necessary to analyse and fix these. For now, mark SME as BROKEN in the hope that we can fix things properly in the near future. As SME is an OPTIONAL part of ARMv9.2+, and there is very little extant hardware, this should not adversely affect the vast majority of users. Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx> Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Marc Zyngier <maz@xxxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # 5.19 Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> Link: https://lore.kernel.org/r/20241106164220.2789279-1-mark.rutland@xxxxxxx Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/Kconfig | 1 + 1 file changed, 1 insertion(+) --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2113,6 +2113,7 @@ config ARM64_SME bool "ARM Scalable Matrix Extension support" default y depends on ARM64_SVE + depends on BROKEN help The Scalable Matrix Extension (SME) is an extension to the AArch64 execution state which utilises a substantial subset of the SVE Patches currently in stable-queue which might be from mark.rutland@xxxxxxx are queue-6.1/arm64-kconfig-make-sme-depend-on-broken-for-now.patch
