Re: Regression: Requiring CAP_SYS_ADMIN for /proc/<pid>/pagemap causes application-level breakage

[Kirill A. Shutemov]

On Wed, Apr 29, 2015 at 02:18:49PM -0700, Linus Torvalds wrote:
> On Wed, Apr 29, 2015 at 2:05 PM, Kirill A. Shutemov
> <kirill@xxxxxxxxxxxxx> wrote:
> >
> > This sounds too ugly to be exposed it as ABI.
> 
> Oh, pretty it ain't. However, regressions in many ways are worse. If
> it makes it possible to not regress...

One idea is to extend kcmp(2) with KCMP_PAGE. idx1 and idx2 are virtual
addresses in two processes. It returns 0 if addresses points to the same
page and 3 otherwise.

Would it be enough for the use case?

I guess it could be too slow to check one page a time...

Invent new kcmpv(2)? ;)

-- 
 Kirill A. Shutemov
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