On Fri, Mar 20, 2020 at 08:53:16AM +0530, Anshuman Khandual wrote: > > > On 03/18/2020 10:31 AM, Anshuman Khandual wrote: > > pud_present() should also check _PAGE_PROTNONE and _PAGE_PSE bits like in > > case pmd_present(). This makes a PUD entry test positive for pud_present() > > after getting invalidated with pud_mknotpresent(), hence standardizing the > > semantics with PMD helpers. > > > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > Cc: Ingo Molnar <mingo@xxxxxxxxxx> > > Cc: Borislav Petkov <bp@xxxxxxxxx> > > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> > > Cc: Dave Hansen <dave.hansen@xxxxxxxxx> > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Cc: x86@xxxxxxxxxx > > Cc: linux-mm@xxxxxxxxx > > Cc: linux-kernel@xxxxxxxxxxxxxxx > > Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> > > --- > > Even though pud_mknotpresent() is not used any where currently, there is > > a discrepancy between PMD and PUD. > > > > WARN_ON(!pud_present(pud_mknotpresent(pud_mkhuge(pud)))) -> Fail > > WARN_ON(!pmd_present(pmd_mknotpresent(pmd_mkhuge(pmd)))) -> Pass > > > > Though pud_mknotpresent() currently clears _PAGE_PROTNONE, pud_present() > > does not check it. This change fixes both inconsistencies. > > > > This has been build and boot tested on x86. > > Adding Kirill and Dan. > > +Cc: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> > +Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Or we can just drop the pud_mknotpresent(). There's no users AFAICS and only x86 provides it. -- Kirill A. Shutemov
