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charset=us-ascii Content-Disposition: inline In-Reply-To: <101ac423-252d-4ef8-a07c-34f5d59820f5@suse.com> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: C2CC114000B X-Stat-Signature: dyy1mykorzgoy73pkxqqeby38pw8j9y5 X-Rspam-User: X-HE-Tag: 1772651595-546519 X-HE-Meta: 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 6wxV39bv cTu7fAD9/KKjMEGPs9FIywjHlQYjOyZ0oAtEBxclX5UiAkIC2EV1cmV+RSVsmm/WIP8grrf8C14nu/PO4cUdKR8O/i6Y+lJN1FkAqABbXi/7YLZwseappdzfB0eut+hdL6CMqo+8gHIlieEs00hje9J4nHNY6tMMNCwMtxAGVFJHRwhn8r4WzntGyuEt4LKAQhcs0U0uEWUV1EsBoY8jGthBZBQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 04, 2026 at 06:29:09PM +0100, Vlastimil Babka wrote: > Why do you keep not CCing people from v1/v2 discussions? David said that > already on v2. It seems rather rude to me. > > On 3/3/26 9:15 PM, Andi Kleen wrote: > > When a smaps mapping is only PMD mappings report the > > PMD page size for MMUPageSize instead of the base page size. > > > > This is a revised version of an earlier patch that tried > > to report multiple page sizes, but there were many objections > > mainly centered around compatibility for mixed page size > > reporting. This patch side steps all of this by > > only handling the non mixed case in the simplest possible way. > > It also avoids a problem introduced with v2 that page sizes > > for mappings with no pages were incorrectly reported. > > > > Signed-off-by: Andi Kleen > > Will this be useful in practice or just confusing? There can be e.g. It might have saved me some wasted time. I found the current situation confusing! > misaligned mappings, or other reasons why there won't be 100% THP > coverage. This all or nothing value (IIUC) seems inferior to the s/nothing/4K like what's there today/ Yes probably multiple page sizes would be better, but I'm not reopening that discussion now. > counters we have that say how much is pmd mapped, so I'm not really sure > it's worth changing this. The other counters still exist of course. I don't see how there can be confusion if we report the correct page size if the mapping is only that page size vs a page size that is not used at all. -Andi