On Mon, Nov 20, 2017 at 3:37 PM, Thomas Gleixner <t...@linutronix.de> wrote: > On Mon, 20 Nov 2017, Andy Lutomirski wrote: >> struct tss_struct { >> /* >> - * The hardware state: >> + * Space for the temporary SYSENTER stack. Used for the entry >> + * trampoline as well. Size it such that tss_struct ends up >> + * as a multiple of PAGE_SIZE. This calculation assumes that >> + * io_bitmap is a multiple of PAGE_SIZE (8192 bytes) plus one >> + * long. > > I don't see how sizeof(tss_struct) is a multiple of PAGE_SIZE > > canary = 8 > stack = 512 > hw_tss = 104 > io bitmap = 8200 > ------------------------- > 8824 > > The alignment is what blows it up to 3 * PAGE_SIZE
Whoops! That *was* correct in the RFC version version, but I changed it and failed to fix the comment.