Hello. Linus Torvalds wrote: > I think Pavel missed the fact that you have to check the VM86 bit in Ah, thanks, I must have forgotten the essentials of the own patch :( > That said, the "ldt_ss" case should be moved _after_ the conditional > tests, since most CPU's out there will do static prediction based on<> > forward/backwards direction if the branch predictor isn't primed. OK, I moved the "ldt_ss" below the check. The new patch is attached. Alan, can you please apply that to an -ac tree? ---- Summary: Attached patch works around the corruption of the high word of the ESP register, which is the official bug of x86 CPUs. The bug triggers only when the one is using the 16bit stack segment, and is described here: http://www.intel.com/design/intarch/specupdt/27287402.PDF Acked-by: Linus Torvalds Acked-by: Petr Vandrovec Acked-by: Pavel Machek Signed-off-by: Stas Sergeev