From nobody Fri Apr 3 22:39:20 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (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 A2EAA3976B7 for ; Mon, 23 Mar 2026 11:08:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774264083; cv=none; b=slmsjgpNnuJv+FSZ1lc2uM7UyUCTsOdG2/SiJQ2OMnrTbA6J4Ro+vIR/9lKKkMD9lwsdwpZhJYV8flQPkA6F77wvWGdrt9nYd/phwNLSXaUwLCnrMBT+5WRolDZ5UCMVQ2ni0iz16+dg4xgWG6H333x3Gvjd7Kl1zwEyCUaqu9U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774264083; c=relaxed/simple; bh=sGE3qogMX8J2qFrjrt53auriN+DGLFlNdBYXb1qnB40=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=nAnwffo6M0Y+N6hh9NLXMqIvIGGfopRRWhl3cf7J2VzZWkri0dq1KrgK6pCVUL6wulsG971Z3nO3XmwAMBr21rkItukyiRCReuVIdOqrI/NpWP4TKWVTmLXFxqzmmFWq6IP3BNL9qlEKkSFl+s4TiltuR7Zel0zp6z/9Ljumk5Y= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: 89aeb99226a811f1a21c59e7364eecb8-20260323 X-CTIC-Tags: HR_CC_COUNT, HR_CC_DOMAIN_COUNT, HR_CC_NAME, HR_CC_NO_NAME, HR_CTE_8B HR_CTT_MISS, HR_DATE_H, HR_DATE_WKD, HR_DATE_ZONE, HR_FROM_NAME HR_SJ_DIGIT_LEN, HR_SJ_LANG, HR_SJ_LEN, HR_SJ_LETTER, HR_SJ_NOR_SYM HR_SJ_PHRASE, HR_SJ_PHRASE_LEN, HR_SJ_WS, HR_TO_COUNT, HR_TO_DOMAIN_COUNT HR_TO_NO_NAME, IP_TRUSTED, SRC_TRUSTED, DN_TRUSTED, SA_EXISTED SN_EXISTED, SPF_NOPASS, DKIM_NOPASS, DMARC_NOPASS, UD_TRUSTED CIE_BAD, CIE_GOOD, CIE_GOOD_SPF, GTI_FG_BS, GTI_RG_INFO GTI_C_BU, AMN_GOOD, ABX_BLACK, ABX_EXPLOIT, ABX_HEURISTIC ABX_MISS_RDNS X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.11,REQID:42812116-3904-4384-bae5-e56b318f6d4c,IP:20, URL:25,TC:0,Content:-25,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,AC TION:release,TS:15 X-CID-INFO: VERSION:1.3.11,REQID:42812116-3904-4384-bae5-e56b318f6d4c,IP:20,UR L:25,TC:0,Content:-25,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTI ON:release,TS:15 X-CID-META: VersionHash:89c9d04,CLOUDID:c09e72561b1725f47da42b384561751d,BulkI D:260323190756G9L0BELF,BulkQuantity:0,Recheck:0,SF:17|19|38|66|78|81|82|10 2|127|850|898,TC:nil,Content:0|15|50,EDM:-3,IP:-2,URL:11|94|81|1,File:nil, RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,D KP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_FAS,TF_CID_SPAM_FSD,TF_CID_SPAM_ULN X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 89aeb99226a811f1a21c59e7364eecb8-20260323 X-User: duanchenghao@kylinos.cn Received: from localhost.localdomain [(183.242.174.23)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA) with ESMTP id 2109757586; Mon, 23 Mar 2026 19:07:53 +0800 From: Chenghao Duan To: pasha.tatashin@soleen.com, rppt@kernel.org, pratyush@kernel.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: jianghaoran@kylinos.cn, Chenghao Duan Subject: [PATCH v2 1/4] mm/memfd: use folio_nr_pages() for shmem inode accounting Date: Mon, 23 Mar 2026 19:07:44 +0800 Message-Id: <20260323110747.193569-2-duanchenghao@kylinos.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260323110747.193569-1-duanchenghao@kylinos.cn> References: <20260323110747.193569-1-duanchenghao@kylinos.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" memfd_luo_retrieve_folios() called shmem_inode_acct_blocks() and shmem_recalc_inode() with hardcoded 1 instead of the actual folio page count. memfd may use large folios (THP/hugepages), causing quota/limit under-accounting and incorrect stat output. Fix by using folio_nr_pages(folio) for both functions. Issue found by AI review and suggested by Pratyush Yadav . https://sashiko.dev/#/patchset/20260319012845.29570-1-duanchenghao%40kylino= s.cn Suggested-by: Pratyush Yadav Signed-off-by: Chenghao Duan --- mm/memfd_luo.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/memfd_luo.c b/mm/memfd_luo.c index b8edb9f981d7..953440994ad2 100644 --- a/mm/memfd_luo.c +++ b/mm/memfd_luo.c @@ -395,6 +395,7 @@ static int memfd_luo_retrieve_folios(struct file *file, struct inode *inode =3D file_inode(file); struct address_space *mapping =3D inode->i_mapping; struct folio *folio; + long npages; int err =3D -EIO; long i; =20 @@ -441,14 +442,15 @@ static int memfd_luo_retrieve_folios(struct file *fil= e, if (flags & MEMFD_LUO_FOLIO_DIRTY) folio_mark_dirty(folio); =20 - err =3D shmem_inode_acct_blocks(inode, 1); + npages =3D folio_nr_pages(folio); + err =3D shmem_inode_acct_blocks(inode, npages); if (err) { - pr_err("shmem: failed to account folio index %ld: %d\n", - i, err); + pr_err("shmem: failed to account folio index %ld(%ld pages): %d\n", + i, npages, err); goto unlock_folio; } =20 - shmem_recalc_inode(inode, 1, 0); + shmem_recalc_inode(inode, npages, 0); folio_add_lru(folio); folio_unlock(folio); folio_put(folio); --=20 2.25.1