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charset=utf-8 Content-Disposition: inline X-Stat-Signature: 7i3do97sbh8usrtst8d3rp5smdtm3rgo X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 2AA1CC0004 X-Rspam-User: X-HE-Tag: 1709880633-84538 X-HE-Meta: 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 MTclWyQE u0FSeWapQhi7HTXJZD8hQ/OklZiRu+oF86HY0Jgt3nAXEOYufVq6e1dgEIHJUlTkNlZeoepOJE/JxXdwzvLZgcgm8V74s1pOpiQXt4VwJ0M3CpAPVQ4LFp5CR5IOxrsToQyqoTbJU/dF4Rq0TT2ODvc2WLuLfSmfwH15nOXfCfnJpzQ0ZrmMujgefNKaUrLrQNm1aIQesSTRT9K5b4kYMIDghdQh1X3ESOLa6DK1QnIXYGFX0uhe+bnD9GGe0eVJ14gIcMcITmPRbwt2+63muysYjuFIFn5RE1rK/lgBosr1/9zURAsIueoU2kbtyfGGvJlQfpc1cZheN36JKNDM6GUFi166E5EdBFuqkRrot0CbTnS5cuOwC8G9Rsy6WadjEttWVId85fWeC66cQYXyTngVnIFAvNCgANqznIlwXIFF9txP7aJ7cOQ3p+McKhqnVXyd2iHTFzFxSXbs= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Mar 07, 2024 at 02:12:33PM -0400, Jason Gunthorpe wrote: > On Wed, Mar 06, 2024 at 06:41:35PM +0800, peterx@redhat.com wrote: > > From: Peter Xu > > > > Swap pud entries do not always return true for pud_huge() for all archs. > > x86 and sparc (so far) allow it, but all the rest do not accept a swap > > entry to be reported as pud_huge(). So it's not safe to check swap entries > > within pud_huge(). Check swap entries before pud_huge(), so it should be > > always safe. > > > > This is the only place in the kernel that (IMHO, wrongly) relies on > > pud_huge() to return true on pud swap entries. The plan is to cleanup > > pXd_huge() to only report non-swap mappings for all archs. > > > > Cc: Alistair Popple > > Signed-off-by: Peter Xu > > --- > > mm/hmm.c | 7 +------ > > 1 file changed, 1 insertion(+), 6 deletions(-) > > Reviewed-by: Jason Gunthorpe > > > @@ -424,7 +424,7 @@ static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end, > > walk->action = ACTION_CONTINUE; > > > > pud = READ_ONCE(*pudp); > > - if (pud_none(pud)) { > > + if (pud_none(pud) || !pud_present(pud)) { > > Isn't this a tautology? pud_none always implies !present() ? Hmm yes I think so, afact, it should be "all=none+swap+present". I still remember I missed that once previously, it's not always obvious when preparing such patches. :( I'll simplify this and also on patch 3. Thanks, -- Peter Xu