On Tue, Feb 20, 2018 at 11:40:06AM +0000, Will Deacon wrote: > Commit 2ce77f6d8a9ae9ce6d80397d88bdceb84a2004cd upstream. > > When KASAN is enabled, the swapper page table contains many identical > mappings of the zero page, which can lead to a stall during boot whilst > the G -> nG code continually walks the same page table entries looking > for global mappings. > > This patch sets the nG bit (bit 11, which is IGNORED) in table entries > after processing the subtree so we can easily skip them if we see them > a second time. > > Cc: <stable@xxxxxxxxxxxxxxx> # 4.14+ Now queued up, thanks. greg k-h