On Wed, Mar 11, 2015 at 06:34:49PM +0100, Oleg Nesterov wrote: > Change flush_thread() to do user_fpu_begin() + restore_init_xstate() > and avoid math_state_restore(). > > Note: "TODO: cleanup this horror" is still valid. We do not need > init_fpu() at all, we only need fpu_alloc() + memset(0). But this needs > other changes, in particular user_fpu_begin() should set used_math(). > > Signed-off-by: Oleg Nesterov <o...@redhat.com> > --- > arch/x86/kernel/process.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c > index dd9a069..c396de2 100644 > --- a/arch/x86/kernel/process.c > +++ b/arch/x86/kernel/process.c > @@ -142,7 +142,8 @@ void flush_thread(void) > /* kthread execs. TODO: cleanup this horror. */ > if (WARN_ON(init_fpu(current))) > force_sig(SIGKILL, current); > - math_state_restore(); > + user_fpu_begin(); > + restore_init_xstate();
Ok, question: so math_state_restore() does kernel_fpu_disable() before doing those, why is it ok for flush_thread() to not do it? -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/