On Mon, Feb 10, 2014 at 2:41 AM, Catalin Marinas <catalin.mari...@arm.com> wrote: > On Mon, Feb 10, 2014 at 10:29:35AM +0000, Catalin Marinas wrote: >> On Sun, Feb 09, 2014 at 10:18:26PM +0000, Kees Cook wrote: >> > diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c >> > index 1f7b1e13d945..ff1559f9200c 100644 >> > --- a/arch/arm/mm/dump.c >> > +++ b/arch/arm/mm/dump.c >> > @@ -264,6 +264,9 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, >> > unsigned long start) >> > note_page(st, addr, 3, pmd_val(*pmd)); >> > else >> > walk_pte(st, pmd, addr); >> > + >> > + if (SECTION_SIZE < PMD_SIZE && pmd_sect(*pmd)) >> > + note_page(st, addr + SECTION_SIZE, 3, pmd_val(pmd[1])); >> >> You can use pmd_large() here as well. >> >> But I think this function is broken (the "for" statement not shown >> here). The pmd_t is 32-bit with classic MMU and it uses pmd++ while the >> address grows by PMD_SIZE (two pmd_t entries). > > Actually it's ok since PTRS_PER_PMD is 1, so it only goes through this > loop once. > > But in your patch shouldn't you check for pmd_large(*(pmd+1))? The first > pmd is already caught by the 'if' statement.
It wasn't clear to me what the logic should be here. If PTRS_PER_PMD is 1, then why is there this second pmd after the first? Shouldn't PTRS_PER_PMD be 2 if that's the case? If that's not the case, then I figured the state of needing to report the 2nd pmd depended on the type of the first one, so that's what I wrote instead of trying to figure out why PTRS_PER_PMD wasn't 2. There's clearly something I'm not understanding in here. :) Thanks! -Kees -- Kees Cook Chrome OS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
