From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5867DC43458 for ; Tue, 7 Jul 2026 20:46:35 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3B59E6B00A7; Tue, 7 Jul 2026 16:46:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 380476B00AD; Tue, 7 Jul 2026 16:46:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 19B8C6B00A7; Tue, 7 Jul 2026 16:46:21 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id DF7C86B00AA for ; Tue, 7 Jul 2026 16:46:20 -0400 (EDT) Received: from smtpin10.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 623B11A057C for ; Tue, 7 Jul 2026 20:46:20 +0000 (UTC) X-FDA: 84963163320.10.9795432 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf04.hostedemail.com (Postfix) with ESMTP id 6BB9440008 for ; Tue, 7 Jul 2026 20:46:18 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=dBNMRtRM; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf04.hostedemail.com: domain of devnull+ackerleytng.google.com@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=devnull+ackerleytng.google.com@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1783457178; h=from:from:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=p1TS7iUwVlQ3ys8+sM4I17N9v7PKkuyu3987p/ity4Y=; b=e37+9jSZcqj7xenUtw7Odz2jnCfv2XjKdcWUYb5gl+NF0iA0OnaNqKaLC76V+X2k8dclst WgnUa/WOhqmvIBIKPufSCcsQUTjWhNHDwJWsYTJ+3gSsZdRUudyNuQ/5OgVvHcd3t5/OQ3 yQHEqNbEglBQpcaRIZm8KUw81E1ZKQM= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=dBNMRtRM; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf04.hostedemail.com: domain of devnull+ackerleytng.google.com@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=devnull+ackerleytng.google.com@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1783457178; b=uzRTxGyBJfFIk4HopafMX3YDSRO5ZbK1iRcPWsRK7O0Cl8UoOk0khclQZPArzEvCyXu82b vqEo9RqufM1841dF8N56nUDAjl/XYDza7CelR6Ay675qk8OzvzDIW8jgbuHwBhB7vvfzPV 8fFBEokSmVBAY/3vkx2jfVRXrYamOgQ= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 94B0D6136C; Tue, 7 Jul 2026 20:46:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPS id 466C6C2BCFF; Tue, 7 Jul 2026 20:46:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1783457177; bh=+0kuj1bG/SlCGtU90RU3Z+4wHYzXatUwjgJpAiL34Ng=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=dBNMRtRM3esgz9pnFgibSTCLZmEmjDGAK9WRa7MJb36G+jj7Xf21lXdQM6yfTwD+f k66oCSCQCh7C9aBtU7zcGojC3Q8uES6Ot8MBUwvqyYTc381vT2K3uBXW8BrW7b4JCm d1LbrWFeCRDxmQymq/XxU7MDKJ0HY59CJBcv7L8536SUE19KZ/796qFrsMh8l6H/FK d/gmGJ+tOeMg/EwVhika3ZVpBd/mIdoUXPhjFPYGruLxddJC5VblKcQWT2yve6Bwhw MtIrFUCbR4cc6YiPSC0hYhrVv1BtxhAv+vXNOfQNXq8mm2CT4vn9bv3tubLcgTE6qB OSXWJ+7i+Dj0Q== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32FFDC44506; Tue, 7 Jul 2026 20:46:17 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Tue, 07 Jul 2026 13:46:11 -0700 Subject: [PATCH 4/4] mm: hugetlb: Move memcg charge earlier to prevent reservation leak MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260707-hugetlb-alloc-failure-fixes-v1-4-5bbd3a4b836d@google.com> References: <20260707-hugetlb-alloc-failure-fixes-v1-0-5bbd3a4b836d@google.com> In-Reply-To: <20260707-hugetlb-alloc-failure-fixes-v1-0-5bbd3a4b836d@google.com> To: Muchun Song , Oscar Salvador , David Hildenbrand , Joshua Hahn , Shakeel Butt , Nhat Pham , Andrew Morton , Peter Xu , Wupeng Ma , fvdl@google.com, rientjes@google.com Cc: vannapurve@google.com, erdemaktas@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1783457176; l=2702; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=byYmVafBqzJqhYJN9f0HauTLLeaXGUi0G31EyYblf3o=; b=LCCWWXJth+OA0REwYwzLBuY8O/lKZjNXSmDWNmT81I+NFmGnhEJ5SQsbNpo6kQIBhWeYFuVMV DdkSTRX873dB9r/qxv8pO0g7vNYeRSDdlMN2+qe4e1MoF21xRLxS0Oq X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 6BB9440008 X-Stat-Signature: hb7rkqude8owo7kuox8fyup83o3obti1 X-HE-Tag: 1783457178-709326 X-HE-Meta: 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 qsHU1IyA VdXHwP9bPMgHZ1OyyesaPFGXhilOF2yulmz6G7v7J+fZyxGpoIgNoDoWMJ2sz1CiuPzeRBe5Vkk1KJusDgdWvo35h39KrPLyanF42MoXvYGk1qiFkesbODCTm/3nIiD4+R2TvIOtHZeHGRxFc9F9xuIK6sxUqkkFUWkv8KcZmm0wyUneA02/zSVMIf2TMO6DowM3qUzuBmDXGQTUHIoz/HWkRCmzG/O+1JRUv3lyKxYqxLnHBkEObjAz5iO5Uh1oSsoIL+VEfkhw7IDDKpHvIZlDrz0LoL/j+e2RMkWe5zFtsIaqNXAOq3PwV+BMnAgLb44s+JL7tLNvu5a8CPJRPj39TW0q1qluXRu38ksAxbSSHJixCDmCeuM7oDLpgWDinU7f1UUOJoQ08Mjg30X+lOCVtNw305bZvQd8WAp/Vor7aW3BeQA7yoLtLHqG8orpQxFyrKkkXLPjwx5xmyMuJ9GqJwjxiq+D8WHQmVY4NqZbin8g= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Ackerley Tng When mem_cgroup_charge_hugetlb() fails, alloc_hugetlb_folio() clears the charges and frees the folio. The reservation committed via vma_commit_reservation() was not undone, leaving the reservation map in an inconsistent state, causing resv_huge_pages to leak when the process exited. Fix this by moving the mem_cgroup_charge_hugetlb() call earlier in alloc_hugetlb_folio(), before vma_commit_reservation() is called. If the charge fails now, the reservation is not yet committed. Jump to out_subpool_put, which will then call vma_end_reservation() to abort the reservation and keep the reservation map and resv_huge_pages counter consistent. Fixes: 991135774c0e0 ("memcg/hugetlb: introduce mem_cgroup_charge_hugetlb") Signed-off-by: Ackerley Tng --- mm/hugetlb.c | 34 ++++++++++++++++++++-------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index e42049e2c038b..6e4acb1f021a5 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2960,6 +2960,25 @@ struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, spin_unlock_irq(&hugetlb_lock); + ret = mem_cgroup_charge_hugetlb(folio, gfp); + /* + * Unconditionally increment NR_HUGETLB here. If it turns out that + * mem_cgroup_charge_hugetlb failed, then immediately free the page and + * decrement NR_HUGETLB. + */ + lruvec_stat_mod_folio(folio, NR_HUGETLB, pages_per_huge_page(h)); + + if (ret == -ENOMEM) { + folio_put(folio); + /* + * Charges to hugetlb_cgroup for usage and + * reservations were already committed, so folio_put() + * would have uncharged those. Go straight to undoing + * subpool charges. + */ + goto out_subpool_put; + } + hugetlb_set_folio_subpool(folio, spool); if (map_chg != MAP_CHG_ENFORCED) { @@ -2987,19 +3006,6 @@ struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, } } - ret = mem_cgroup_charge_hugetlb(folio, gfp); - /* - * Unconditionally increment NR_HUGETLB here. If it turns out that - * mem_cgroup_charge_hugetlb failed, then immediately free the page and - * decrement NR_HUGETLB. - */ - lruvec_stat_mod_folio(folio, NR_HUGETLB, pages_per_huge_page(h)); - - if (ret == -ENOMEM) { - folio_put(folio); - goto err; - } - return folio; out_uncharge_cgroup: @@ -3020,7 +3026,7 @@ struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, out_end_reservation: if (map_chg != MAP_CHG_ENFORCED) vma_end_reservation(h, vma, addr); -err: + /* * Return -ENOSPC when this function fails to allocate or * charge a huge page. If a standard (PAGE_SIZE) page -- 2.55.0.795.g602f6c329a-goog