On Tue, Dec 12, 2017 at 11:21 AM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: > > That has nothing to do with the user installed LDT. The kernel does not use > and rely on LDT at all. Sure it does. We end up loading the selector for %gs and %fs, and those selectors end up being connected with whatever user-mode has set up for them. We then set the FS/GS base pointer to a kernel-specific value, but that is _separately_ from the actual accessed bit that is in the selector. So the kernel doesn't care, but the kernel definitely uses them. Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>