On Mon, 2008-12-15 at 13:21 +0800, Herbert Xu wrote: > On Mon, Dec 15, 2008 at 01:14:59PM +0800, Huang Ying wrote: > > > > The PadLock instructions don't use/touch SSE registers, but might cause > > DNA fault when CR0.TS is set. So it is sufficient just to clear CR0.TS > > before executed. > > > > The AES-NI instructions do use SSE registers. Considering the following > > This really sucks as more than half of the kernel AES users are > in softirq context. Someone hit the guy who designed this with > a clue-bat please! > > > To solve the above issue, the following methods can be used: > > > > a. Do not touch SSE state in soft_irq > > b. Disable/restore soft_irq in kernel_fpu_begin/kernel_fpu_end > > c. Use a per-CPU data structure to save kernel FPU state during > > soft_irq. > > > > The mothod a is used in patch. > > Could you run the tcrypt speed test on this and measure the > difference between the native AES vs. the fallback? Depending > on the difference I think we'd want to consider b) or c). I do not have appropriate machine at hand, I will contact my colleague for testing and post the results later. Best Regards, Huang Ying
Attachment:
signature.asc
Description: This is a digitally signed message part
