• Julien Grall's avatar
    arm64: cpufeature: Effectively expose FRINT capability to userspace · 7230f7e9
    Julien Grall authored
    The HWCAP framework will detect a new capability based on the sanitized
    version of the ID registers.
    
    Sanitization is based on a whitelist, so any field not described will end
    up to be zeroed.
    
    At the moment, ID_AA64ISAR1_EL1.FRINTTS is not described in
    ftr_id_aa64isar1. This means the field will be zeroed and therefore the
    userspace will not be able to see the HWCAP even if the hardware
    supports the feature.
    
    This can be fixed by describing the field in ftr_id_aa64isar1.
    
    Fixes: ca9503fc ("arm64: Expose FRINT capabilities to userspace")
    Signed-off-by: default avatarJulien Grall <julien.grall@arm.com>
    Cc: mark.brown@arm.com
    Signed-off-by: default avatarWill Deacon <will@kernel.org>
    7230f7e9
cpufeature.c 69.4 KB