From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.208 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793187223; b=VzsMdyoxzOK5U+/dKZ9aQgAz7LNWmdG4BjzhRQwj4neKsWuIl6bdmjUKwHvs6ktNtffG LtDeZVnBD8dG26NZXIpD/iL/3u7V+E7JlxjSShJGtVSLBubs8392gTbT1A/WH+UYukgX/ v7ZXWfqNgi463zRd43qp7wQUEDDcR6m41lcEAyXmbLyU6OvEF2bMFu1w2rnM647AQhmuH P44M6Lc/gDhRfD2Dtk/v0A8E/c0fBEUMK179PIarwbSXy0QoNgJjwYcWO5+q2dm6YtllI T+oklX54QLGk6sPs45Al7bFw8ujLuU0Z4jv8/7csEnFPsCtKhV3gpUXjeT3v/qQ9hoA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793187223; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-ID: X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=eZqrRAG8TXvwglBXLrHZsQwJkLFjvZPLEOndgDiI778=; b=tNw/i8eg96r1KwlCE0N8cbArqiGWHCobWQP7TNabdWLk1y4bbLuY18SU3Wu4qTV1wP3s atNeVsFcO91s3Y06a40lPi5B0Qj7BdeaCzUWTdmiu0QbUPoraeHnJjRZnI1KkaU9HtL67 Ef0KJKUSBFwctuc9WIpCMlmohbjjDcwhvyMclSU9UxFTzOrM1MvFgxxpJaQLzQJoA1do7 gX+XeLSgJifpQ9WOXpJo+9LtsulUHWdKZdjgAOJH3DGlPAFkK6QEGnUx5LWTPBYZmv9ze Zs8/PVV0nlj5Sd9qFOKMUYf01u2RHj/NEHumw49UqfAZaAi2bsL/bjk/RnW3kfKuYOg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=cJbsOXPg; arc=none smtp.remote-ip=95.215.58.208 Received: from mta1.migadu.com (out-208.mta1.migadu.com [95.215.58.208]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79B1B606A31E for ; Wed, 28 Oct 2026 11:33:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 79B1B606A31E Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=cJbsOXPg X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=YIi5cqsLiN4R7MlgUKWwk2aRnfwmDatK/C8j4Mm1VPw=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793187220; v=1; x=1793792020; b=cJbsOXPg1eiyW6Q19AS227PbMKVR1RRB6NBAsYxGXvQGcDXq8HnIJDr9nVb2pSOtFly873f8 tYJTC8BkU6mPcj7004twsRVNb4q9MYZFEMEmOcK/I6daUo22ce8QfHqNEI9Hs4m38cPp03mQ6Fm vGt/eYv9zwbJ1fjV+xp68Meo= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id d9ad0361b8284d86; Wed, 28 Oct 2026 11:33:40 +0000 X-Mizu-Trace-ID: d9ad0361b8284d86 X-Migadu-Flow: FLOW_OUT From: Kaitao Cheng To: Muchun Song , Oscar Salvador , David Hildenbrand , Andrew Morton Cc: Baolin Wang , Mike Kravetz , Frank van der Linden , Michal Hocko , Joshua Hahn , Chris Down , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kaitao Cheng Subject: [PATCH 2/3] mm/hugetlb: preserve CMA flag when returning folios to the pool Date: Wed, 28 Oct 2026 19:33:18 +0800 Message-ID: <20261028113319.38544-3-kaitao.cheng@linux.dev> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20261028113319.38544-1-kaitao.cheng@linux.dev> References: <20261028113319.38544-1-kaitao.cheng@linux.dev> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Kaitao Cheng When vmemmap restoration fails, add_hugetlb_folio() returns the folio to the hugetlb pool. It clears folio->private and restores only HPG_vmemmap_optimized, losing HPG_cma on CMA-allocated folios. A later successful free then bypasses hugetlb_cma_free_frozen_folio() and returns the pages through free_frozen_pages(). The CMA allocation bitmap remains set, so the range is unavailable for future CMA allocations. Save the CMA flag before resetting folio->private and restore it along with the vmemmap optimization flag. Fixes: d2d786714080 ("mm/hugetlb: enable bootmem allocation from CMA areas") Closes: https://sashiko.dev/#/bug/linux-5363eb09-9c3c-4f8b-9f3c-a998a8c4b258 Signed-off-by: Kaitao Cheng --- mm/hugetlb.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 4a008afaedf9..8da4bab676c9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1437,6 +1437,7 @@ void remove_hugetlb_folio(struct hstate *h, struct folio *folio, void add_hugetlb_folio(struct hstate *h, struct folio *folio, bool adjust_surplus) { + bool cma = folio_test_hugetlb_cma(folio); int nid = folio_nid(folio); VM_BUG_ON_FOLIO(!folio_test_hugetlb_vmemmap_optimized(folio), folio); @@ -1453,9 +1454,11 @@ void add_hugetlb_folio(struct hstate *h, struct folio *folio, } __folio_set_hugetlb(folio); - /* Clear all folio->private flags except hugetlb_vmemmap_optimized. */ + /* Preserve the vmemmap optimization state and CMA allocation origin. */ folio->private = NULL; folio_set_hugetlb_vmemmap_optimized(folio); + if (cma) + folio_set_hugetlb_cma(folio); arch_clear_hugetlb_flags(folio); enqueue_hugetlb_folio(h, folio); -- 2.53.0