On Fri, Jan 29, 2021 at 09:37:30AM -0800, Sean Christopherson wrote: > On Thu, Jan 28, 2021, ira.we...@intel.com wrote: > > From: Ira Weiny <ira.we...@intel.com> > > > > There is no reason to alloc a page and kmap it to store this temporary > > data from the user. > > Actually, there is, it's just poorly documented. The sigstruct needs to be > page aligned, and the token needs to be 512-byte aligned. kmcalloc doesn't > guarantee alignment. IIRC things will work until slub_debug is enabled, at > which point the natural alignment behavior goes out the window.
Well, there still is absolutely no need for the kmap as you can use page_address for a GFP_KERNEL allocation.
