• Russell King's avatar
    ARM: VFP: fix vfp thread init bug and document vfp notifier entry conditions · 0d782dc4
    Russell King authored
    When the VFP notifier is called for flush_thread(), we may be
    preemptible, meaning we might migrate to another CPU, which means
    referencing the current CPU number without some form of locking is
    invalid, and can cause data corruption.
    
    For the most cases, this isn't a problem since atomic notifiers are run
    under rcu lock, which for most configurations results in preemption
    being disabled - except when the preemptable tree-based rcu
    implementation is selected.
    
    Let's make it safe anyway.
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    0d782dc4
vfpmodule.c 13.4 KB