From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (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 C46DA31A045; Sun, 20 Sep 2026 13:12:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=150.107.74.76 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789909965; cv=none; b=ctGoCt0lngKxTe7fb9dsD+JXFl99U0byKND35u9TBfcaQPEUfgJh1FoVAoIaqydFmxI6b1JrxAYVouua86sbTZU22UWY6j49eoWpTlAYHwoFjyXJ2KhdHrg0x52ECjFheEz2ppC+Otdh9BT23vEB/AfsPEMIuCG2+XNcsUsdRww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789909965; c=relaxed/simple; bh=eDMI5Ku1H/ICGHVjdTySIeVCjxxQYch6/DXg1E0Ox1Y=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aWGz4yk7DAL3X9vypNWRyyRyUt87z+8cu9LG7Mio0OH5X5YyjpA5rlQrkUeKUy5kgFNB5V1RLFN3/wHx4rA8s7UQW09uGyp0rbusitqI+AQbaoW1nB/tiBx5TitMwy30j5b7Y00H0vGq5TPbZx3Duih5AQ/qCtMFrvxhsBgkZUQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au; spf=pass smtp.mailfrom=canb.auug.org.au; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b=DQ2H8v9F; arc=none smtp.client-ip=150.107.74.76 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b="DQ2H8v9F" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canb.auug.org.au; s=202503; t=1789909929; bh=By7CwzjEKuoPxXJ29LeNnqaFT2rmfr7n3560XH0PorE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=DQ2H8v9FwIRJR+CxHwYdJxr4SPzaQPc04V2zEUJep0JgST2APTgnSWGDDwsA4K617 AzkTMJW7n61be6GuH1dfOqfwJ8VxjlPTH3+9BA9OdkJJXnBtX2Z/6WVuZrn9+PpoQL 85Eg1wWuFh05BBHBc8waJ6d+EWyjRQvsc/UBE0nGzvJgqHjuCR4uypW9tMLS4hFy7l P18eTT4nMSFiilKUPUJmy8kjuV+1UELTDGuIdliyTOARhGuDeNE5Mw0IjMgFPpU28X 8mFeNEA24qhQHYc9Pv4NluEPJTh4p8Qni9WMNG6rHkITNFfjlyVqcLYi27wqQ3h/FI fHe3rJrljwFiA== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mail.ozlabs.org (Postfix) with ESMTPSA id 4hnmwl5VJvz4w1k; Sun, 20 Sep 2026 23:12:07 +1000 (AEST) Date: Sun, 20 Sep 2026 23:12:26 +1000 From: Stephen Rothwell To: Tao Cui Cc: linux-next@vger.kernel.org, Jens Axboe , Damien Le Moal , linux-block@vger.kernel.org, cuitao@kylinos.cn, Mark Brown Subject: Re: next-20260917 and next-20260918: merge of the block tree breaks all zoned devices Message-ID: <20260920231226.771a0e21@canb.auug.org.au> In-Reply-To: <20260920125846.1806521-1-cui.tao@linux.dev> References: <20260920125846.1806521-1-cui.tao@linux.dev> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/R3TRsirW5mdUq_ZFzNgejzQ"; protocol="application/pgp-signature"; micalg=pgp-sha256 --Sig_/R3TRsirW5mdUq_ZFzNgejzQ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Tao, On Sun, 20 Sep 2026 20:58:34 +0800 Tao Cui wrote: > > Hi Stephen, I no longer run linux-next, please email Mark Brown (cc'd). [The rest kept for Mark's benefit] > I ran into this while testing a blk-iocost series of mine (charging > zone appends as writes) against a zoned null_blk: the device simply > does not show up, whether configured through module parameters or > configfs. null_blk prints "using native zone append" and then > add_disk() fails silently with -ENODEV. >=20 > My series only touches blk-iocost.c, and the failure reproduces on > plain linux-next, so it is not mine. Bisecting over the tags (qemu, > "null_blk.zoned=3D1 null_blk.gb=3D1 null_blk.zone_size=3D64" on the comma= nd > line) narrows it down to one day: >=20 > next-20260916: nullb0 created, /sys/block/nullb0/queue/zoned =3D host-m= anaged > next-20260917: no device, add_disk() fails > next-20260918: same failure >=20 > The only blk-zoned.c changes between next-20260916 and next-20260917 > come in through the merge of the block tree, and next-20260918 repeats > the same resolution in the same place: >=20 > 66c8b6b56c09 ("Merge branch 'for-next' of .../axboe/linux.git", 2026-09= -17) > a9ce2250a714 ("Merge branch 'for-next' of .../axboe/linux.git", 2026-09= -18) >=20 > As far as I can tell the resolved disk_revalidate_capacity() matches > neither parent: it gains a >=20 > if (args->capacity >=3D args->nr_zones) >=20 > check that compares a sector count against a zone count, with > args->nr_zones still 0 on the first call, so it always trips and > blk_revalidate_disk_zones() always returns -ENODEV. The zone_sectors > power-of-two check that both parents have is gone as well. This hits > every zoned device, not just null_blk. >=20 > Taking the axboe side of the function makes nullb0 come back on > next-20260918 here (host-managed, chunk_sectors 131072), so it looks > like the merge should just have taken that side. >=20 > Same conflict, same bad outcome twice in a row now, so tomorrow's > merge may hit it again unless the block tree has moved on in this > area. >=20 > Regards, > Tao >=20 --=20 Cheers, Stephen Rothwell --Sig_/R3TRsirW5mdUq_ZFzNgejzQ Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAmqv27oACgkQAVBC80lX 0Gz6awf7BN38hUqChpXUqxW3J1gLKOkkrAYOfnA8o1ydQwT/pyQfvAygYuP6/Dnu gYpLJx2vB8citv2vakqdnJdaLJMlIcRWWsr/cm5jMNnPctjkEEh41EQ7f9QBmhL4 DDCCl0FZpz3OhoDfBF+Pq2yMt6kcovw7/V23YKYQWdLDk4M77o88O7X/eF7rHBLP 3ztPpT0JMiIQhLSDSMdEkRMKJAC7kwon1OP6BngUtAHk1ekg4YNB0uj2IivvuCSP zmVAWqVfBAxLCFV0QrLe+DJD5WHAPWzSk+JBlJII2Fh2iZpRa03Xl2HRyUyPR4yO yxCbLEZGo5c+WYMkEsTt05O255S1eA== =9NOG -----END PGP SIGNATURE----- --Sig_/R3TRsirW5mdUq_ZFzNgejzQ--