From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-187.mta0.migadu.com [91.218.175.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B252E45D1A8 for ; Mon, 14 Sep 2026 12:31:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.187 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789389117; cv=none; b=I9bdFK+5b0DE7KsHL4VTnW0PtRgHrm2dzBnIF3GTxBkDPFfsNbWfMsMkOOXoxLZOKKWAxWKBkcgUTPMBXxkljadBDBtG/N0oEny1HVll7YyQqPxcLfjkVyWs48op4J/libVUqUcECj4Axe2Iizx5O0GIdMgVEUVUT1FJC0rWc4Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789389117; c=relaxed/simple; bh=0pxvz2tA8d/MqnhA+ARBMVfrRyK0IVtO3kcKq5jVvyM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FmZTSM1OeUHElDfzrs5HiU/QbkiJyB3z3ui4CWdCqsIsxj5hAxnX0xoIo2jMyxD4E9GP8IGjRIYaowXiCBQ/8Kq0UC3rPNUPh0pnAxXD326VbY5Ia0OFxiG/rvUdsKXb9MHS5CfpMmVZxLR8FPMPCOnvtGAG1KFC1DTIuyrgAr4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=cUeMcohk; arc=none smtp.client-ip=91.218.175.187 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) header.d=linux.dev header.i=@linux.dev header.b="cUeMcohk" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=0pxvz2tA8d/MqnhA+ARBMVfrRyK0IVtO3kcKq5jVvyM=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1789389105; v=1; x=1789993905; b=cUeMcohkP1jsBtxE6fis2Pimxgeg45wvpSINk23Rh9u406i7JrWBmjRGOU3FLpGJil5tQs34 Y27hM6JDd30TjiXdkGpgQR2wCV/TAZjVMnElrtxK+mKnmfvZQax78mkl+4MNh4kAKDzHPp8pMWQ LVFNKoDG/PvexTPaz3c7SExU= X-Envelope-To: linux-kernel@vger.kernel.org Received: by mta10.migadu.com with ESMTPS id a8f2f31ac8e52b34; Mon, 14 Sep 2026 12:31:45 +0000 X-Mizu-Trace-ID: a8f2f31ac8e52b34 X-Migadu-Flow: FLOW_OUT From: Usama Arif To: Andrew Morton , david@kernel.org, chrisl@kernel.org, kasong@tencent.com, ljs@kernel.org, ziy@nvidia.com, linux-mm@kvack.org Cc: ying.huang@linux.alibaba.com, Baoquan He , willy@infradead.org, youngjun.park@lge.com, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, alex@ghiti.fr, kas@kernel.org, baohua@kernel.org, dev.jain@arm.com, baolin.wang@linux.alibaba.com, Nico Pache , Liam R. Howlett , ryan.roberts@arm.com, Vlastimil Babka , lance.yang@linux.dev, linux-kernel@vger.kernel.org, nphamcs@gmail.com, shikemeng@huaweicloud.com, yosry@kernel.org, qi.zheng@linux.dev, luizcap@redhat.com, kernel-team@meta.com, Usama Arif Subject: [RESEND v7 18/29] mm: free PMD swap entries in zap_huge_pmd() Date: Mon, 14 Sep 2026 05:28:08 -0700 Message-ID: <20260914122950.3283997-19-usama.arif@linux.dev> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260914122950.3283997-1-usama.arif@linux.dev> References: <20260914122950.3283997-1-usama.arif@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit zap_huge_pmd() assumes any non-present PMD it clears references a folio, so a PMD swap entry would reach normal_or_softleaf_folio_pmd() and warn. Worse, nothing would release the slots it points at: unmapping a swapped-out THP would leak the whole PMD's worth of swap. Handle it before the folio lookup, as zap_pte_range() already does for a PTE swap entry. Signed-off-by: Usama Arif --- mm/huge_memory.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index d3d0fec9a5ff3..689a1f4286471 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2628,6 +2628,16 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, arch_check_zapped_pmd(vma, orig_pmd); tlb_remove_pmd_tlb_entry(tlb, pmd, addr); + if (pmd_is_swap_entry(orig_pmd)) { + softleaf_t entry = softleaf_from_pmd(orig_pmd); + + zap_deposited_table(mm, pmd); + spin_unlock(ptl); + swap_put_entries_direct(entry, HPAGE_PMD_NR); + add_mm_counter(mm, MM_SWAPENTS, -HPAGE_PMD_NR); + return true; + } + is_present = pmd_present(orig_pmd); folio = normal_or_softleaf_folio_pmd(vma, addr, orig_pmd, is_present); has_deposit = has_deposited_pgtable(vma, orig_pmd, folio); -- 2.53.0-Meta