On Wed, Mar 24, 2021 at 11:22:46AM -0700, ira.weiny@xxxxxxxxx wrote: > From: Ira Weiny <ira.weiny@xxxxxxxxx> > > kmap is inefficient and is being replaced by kmap_local_page(), if > possible. Nit: just saying that something is inefficient is not enough. Always should have something to back it up. > That said, there is no readily apparent reason why initp_page needs to > be allocated and kmap'ed() except that 'sigstruct' needs to be page > aligned and 'token' 512 byte aligned. > > Rather than change this kmap() to kmap_local_page() use kmalloc() > instead because kmalloc() can gives this alignment when allocating > PAGE_SIZE bytes. > > Remove the alloc_page()/kmap() and replace with kmalloc(PAGE_SIZE, ...) > to get a page aligned kernel address. > > In addition add a comment to document the alignment requirements so that > others don't attempt to 'fix' this again. I'm a bit confused based on this commit message. Why is kmap_local_page() better, and why kmalloc() is the ultimate choice of all three options? > > Cc: Sean Christopherson <seanjc@xxxxxxxxxx> > Cc: Jethro Beekman <jethro@xxxxxxxxxxxx> > Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx> > Cc: Dave Hansen <dave.hansen@xxxxxxxxx> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> /Jarkko
