Re: [git pull] changes for tip, and a nasty x86 page table bug

Linus Torvalds
2009-02-20T02:01:53Z

On Thu, 19 Feb 2009, Steven Rostedt wrote:
>
> In doing this change, I stumbled upon a nasty bug in the page handling
> of the x86 code, where we can fall into a state where the PTE
> has the RW bit set, but the PMD does not.

How do we ever have a PMD that is read-only? That sounds like a bug to
begin with. There's no reason to ever do that.

In fact, it should trigger the pmd_bad() tests if it ever happens,
wouldn't it? We want all the _KERNPG_TABLE bits to always be set, no?

Linus