From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E6855354AF5 for ; Wed, 22 Oct 2025 14:34:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761143656; cv=none; b=sYct1M2KTONIthzF+AJ3k2VZm57FbccmvfjMVBiGtqR2IAnWs56C3WMp832YtJztdksvmEjOMEUni3gOiWic0UWQwPv5UEOQJIw8Jmgnfj9MVhnCJEhaGAgur/dRtUelrRkb9JUAhmFSTXN82UEd0JxGYzNHrXuez2FD02+3sl8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761143656; c=relaxed/simple; bh=PE0w9weBA06UY1ADMvuQ7RDRF1VFjwoEQh225hRpYZc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=mvUQfaFZQUX30gO3Y9Tv092GJXasxdqDwsQLgwwsLwly/aSEpMqDoVOtKQGsLJvBRdV3VTCk4b3nXhfJg2Os3BMVUA6aQHG1oUJ5ijwc1d5VYDsvqMHP+lA25d/CV/GU1pIk3EYulKuJWWBFXVw/X2liqo2ICIZHZxvmvQMTwQ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cP9wbkEh; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cP9wbkEh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96649C4CEE7; Wed, 22 Oct 2025 14:34:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761143655; bh=PE0w9weBA06UY1ADMvuQ7RDRF1VFjwoEQh225hRpYZc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cP9wbkEhPM5LIDakVffo66AHNLBN+38mt7kw0Nz1jjGM2DTXe/G7XuJ/6OFlVBDOR 13ysGZEgl7Yl6Kk7OLgtMXAGd+Rc/TAHxOWT5ohaXNSYIWzV1lGviaTtyV/yQXdjhq kh6G0Dujl3w7LOIfgQW/e/jH/m9lfkPmqFaif4OrMHSPse4klWA1BdT76iUoBIHvKL qkzYWKIk6slN1bfOqe+4G2oUCFmRrjagLn1fpxjjhAFqCvjDzlIZd/Jpt7HIfH+a/D XkxNnpKeeolCDTKG2t0QQK573TSGGgDAGoOHy62RkvYg1tvs9a4RfHZbeRybsew7qp NBpmfpZajkRGA== Date: Wed, 22 Oct 2025 15:34:10 +0100 From: Mark Brown To: Deepanshu Kartikey Cc: muchun.song@linux.dev, osalvador@suse.de, david@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, syzbot+f26d7c75c26ec19790e7@syzkaller.appspotmail.com Subject: Re: [PATCH v8] hugetlbfs: move lock assertions after early returns in huge_pmd_unshare() Message-ID: <080b64d6-7bc3-4ba6-ab76-e1fe728bff88@sirena.org.uk> References: <20251014113344.21194-1-kartikey406@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="A/QWAtEIee2YEtfF" Content-Disposition: inline In-Reply-To: <20251014113344.21194-1-kartikey406@gmail.com> X-Cookie: Thank God I'm an atheist. --A/QWAtEIee2YEtfF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Oct 14, 2025 at 05:03:44PM +0530, Deepanshu Kartikey wrote: > When hugetlb_vmdelete_list() processes VMAs during truncate operations, > it may encounter VMAs where huge_pmd_unshare() is called without the > required shareable lock. This triggers an assertion failure in > hugetlb_vma_assert_locked(). On current mainline this translates the test from a fail to a skip on the Raspberry Pi 4: # # ------------------------- # # running ./hugetlb-madvise # # ------------------------- # # [SKIP] # ok 6 hugetlb-madvise # SKIP # # hugepages not supported due to: [ 0.000000] Kernel command line: console=ttyS1,115200n8 root=/dev/nfs rw nfsroot=172.16.0.2:/var/lib/lava/dispatcher/tmp/1991635/extract-nfsrootfs-9ik0m73w,tcp,hard secretmem.enable hugepagesz=32M hugepages=0:4 default_hugepagesz=2M hugepages=0:128 hugepagesz=64K hugepages=0:4 kpti=off ip=dhcp [ 0.000000] Unknown kernel command line parameters "hugepagesz=64K hugepages=0:4 default_hugepagesz=2M", will be passed to user space. which used to DTRT but I doubt is due to this specific patch... --A/QWAtEIee2YEtfF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmj462EACgkQJNaLcl1U h9C5YQf8DzoRtaemjFkXnj0s/9uWQGFbpRQHBXfRESoB/flbWhlkLXd4iI9D82Nc Aaeg06+b4foXvsPsacRLjZTnd65mH73P5gFN35MInqU2RvSb1RCNP8/8eJJyieeu s+r+EaPtFciPovmHxXaHkA4xvBVUz0q5Fty7Ndz2perwfPSWryAXyonZyw1cqJFk e7gtvXR7FwlZs2KyRl7XPq6RJBpN+jTHUJPMtlNsdlYgaV9n/8LyKAqL6YBHL3QT w9wYuSt1ijYYYCcH/xhMbUk02MD+ntabLMMTFs/4kefCvvFCDVZB9u2ucfJ0pE9e 9oLnPQ3QJ2uo91+tvTbJWhsAEWHsfQ== =5pOg -----END PGP SIGNATURE----- --A/QWAtEIee2YEtfF--