From nobody Wed Dec 17 17:27:49 2025 Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B50AC13BC30; Tue, 9 Jul 2024 07:40:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=150.107.74.76 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720510860; cv=none; b=X8g/jWq8SKAemRSljG2EGMhI87tgGoJp3KV+9cpkqK90FoVM2oDyAGqNoFxP9lAweWSNHqgWmKkasZK4zefeIO167bFuE9lzTBA+4xFefHgMOtcckmuhaTMUscYkdkpb3FzruK422cPC0d4Gnte89SWE1JmFmM3pNEYFsrsDcQQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720510860; c=relaxed/simple; bh=mYo7BBhpvpBBP6FL1/v+q7xQ7NJIq+ysLMBI1P5ITMc=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type; b=YMFsH+wXjc1SgzMixiaf3tqbotWDSW2zjIaOFXClcpHWzbvjfbLhi51Sfk8v9RJprzgUSb82SQew5+VDeHZMDYh9ySgUY/yZZx/40nImGi18YLgFNkG4eEXijQR60hYeZt0Dmlw/uuBvnbY8oRKN3mOCB8hK8CXPa5erPnse3YI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au; spf=pass smtp.mailfrom=canb.auug.org.au; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b=ohzxsFGG; arc=none smtp.client-ip=150.107.74.76 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b="ohzxsFGG" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canb.auug.org.au; s=201702; t=1720510855; bh=OwVQjnWdc27b9qsSsgiOeJjlBd4pbZkQSedap0Ld7VQ=; h=Date:From:To:Cc:Subject:From; b=ohzxsFGG8wwni+M09QuRQ3hBteffi336ndNeCuSnZK8Efyp+CfyQ73tpnzT99Voh/ r+146Vl0EdRwaXYDGGBtlVSJd+sA/jtACtQP43xc2x1yNxeYTk2LOuMuuW+U5SP8oh rkTtWTXibjvTRZA4+0kIBEdN4ENpJyimugxdBF7IkPoEOZt4D9hskl5EyrRyfpfBQT Za4doTFYFwDTgrVjh1RFVQQrNPyfS+joFzHEClI1cuRrg8YFxnkrRz5oBPIP/KuSjb 1yTARMy4ip7R3LQZ79nMpW7YHbVfWKOTYr1aTCxJd8ySyNe633p4eZknAX52dkFF/J ZaEmwtfDiasHQ== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4WJCbB4M48z4w2R; Tue, 9 Jul 2024 17:40:54 +1000 (AEST) Date: Tue, 9 Jul 2024 17:40:53 +1000 From: Stephen Rothwell To: Theodore Ts'o , "Jason A. Donenfeld" , Andrew Morton Cc: Barry Song , Barry Song , Lance Yang , Linux Kernel Mailing List , Linux Next Mailing List Subject: linux-next: manual merge of the random tree with the mm-stable tree Message-ID: <20240709174053.051a46a4@canb.auug.org.au> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/Nss_ongiZk.IhXDCBHpNi9z"; protocol="application/pgp-signature"; micalg=pgp-sha256 --Sig_/Nss_ongiZk.IhXDCBHpNi9z Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Hi all, Today's linux-next merge of the random tree got a conflict in: mm/rmap.c between commits: 26d21b18d971 ("mm/rmap: remove duplicated exit code in pagewalk loop") 15bde4abab73 ("mm: extend rmap flags arguments for folio_add_new_anon_rma= p") from the mm-stable tree and commit: 94beef29e110 ("mm: add MAP_DROPPABLE for designating always lazily freeab= le mappings") from the random tree. I fixed it up (see below) and can carry the fix as necessary. This is now fixed as far as linux-next is concerned, but any non trivial conflicts should be mentioned to your upstream maintainer when your tree is submitted for merging. You may also want to consider cooperating with the maintainer of the conflicting tree to minimise any particularly complex conflicts. --=20 Cheers, Stephen Rothwell diff --cc mm/rmap.c index 8616308610b9,1f9b5a9cb121..000000000000 --- a/mm/rmap.c +++ b/mm/rmap.c @@@ -1394,27 -1384,26 +1394,30 @@@ void folio_add_anon_rmap_pmd(struct fol * * Like folio_add_anon_rmap_*() but must only be called on *new* folios. * This means the inc-and-test can be bypassed. - * The folio does not have to be locked. + * The folio doesn't necessarily need to be locked while it's exclusive + * unless two threads map it concurrently. However, the folio must be + * locked if it's shared. * - * If the folio is pmd-mappable, it is accounted as a THP. As the folio - * is new, it's assumed to be mapped exclusively by a single process. + * If the folio is pmd-mappable, it is accounted as a THP. */ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *= vma, - unsigned long address) + unsigned long address, rmap_t flags) { - int nr =3D folio_nr_pages(folio); + const int nr =3D folio_nr_pages(folio); + const bool exclusive =3D flags & RMAP_EXCLUSIVE; + int nr_pmdmapped =3D 0; =20 VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio); + VM_WARN_ON_FOLIO(!exclusive && !folio_test_locked(folio), folio); VM_BUG_ON_VMA(address < vma->vm_start || address + (nr << PAGE_SHIFT) > vma->vm_end, vma); -=20 - if (!folio_test_swapbacked(folio)) + /* + * VM_DROPPABLE mappings don't swap; instead they're just dropped when + * under memory pressure. + */ - if (!(vma->vm_flags & VM_DROPPABLE)) ++ if (!folio_test_swapbacked(folio) && !(vma->vm_flags & VM_DROPPABLE)) __folio_set_swapbacked(folio); - __folio_set_anon(folio, vma, address, true); + __folio_set_anon(folio, vma, address, exclusive); =20 if (likely(!folio_test_large(folio))) { /* increment count (starts at -1) */ @@@ -1858,8 -1862,15 +1867,13 @@@ static bool try_to_unmap_one(struct fol * discarded. Remap the page to page table. */ set_pte_at(mm, address, pvmw.pte, pteval); - folio_set_swapbacked(folio); + /* + * Unlike MADV_FREE mappings, VM_DROPPABLE ones + * never get swap backed on failure to drop. + */ + if (!(vma->vm_flags & VM_DROPPABLE)) + folio_set_swapbacked(folio); - ret =3D false; - page_vma_mapped_walk_done(&pvmw); - break; + goto walk_abort; } =20 if (swap_duplicate(entry) < 0) { --Sig_/Nss_ongiZk.IhXDCBHpNi9z Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAmaM6YYACgkQAVBC80lX 0GybgAf9ECAKGIckkbB4BocYWJ2LMVtImP9MpX5fijc2X7IUsowkamBueLMpgVIa o06Z6BEgfLrs5IDk/2KJLh2blwxaub/cQJbIylL4BiyGTKQM6+TwvuBDDbNESaQX rH9C5CrGBjNDFCL+R0qOS0NyK98Q9gOLb7MpsdnI3KjKYPczM4TVwQgKcpn8UFBG 6szVfoxMtWWspV6rvMDRKCrqoKn8SFY+1n2yB0grzs9ZYnY4jooO49xqyiwbaqlh xqN+gDGASx7jZ35vH5qFfMvHiUNZxr5fPKsR06nPHk7H4xpOtrAMIRvTAxH8/eIl B+IPAD1AUGOo/PXILnAJDPjyZZ5igw== =xolW -----END PGP SIGNATURE----- --Sig_/Nss_ongiZk.IhXDCBHpNi9z--