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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D572C4360F for ; Wed, 20 Feb 2019 11:45:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C4FF2086C for ; Wed, 20 Feb 2019 11:45:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726396AbfBTLpP (ORCPT ); Wed, 20 Feb 2019 06:45:15 -0500 Received: from mout.gmx.net ([212.227.15.18]:48631 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726197AbfBTLpP (ORCPT ); Wed, 20 Feb 2019 06:45:15 -0500 Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.com (mrgmx001 [212.227.17.184]) with ESMTPSA (Nemesis) id 0LkfdE-1hUebA1uqK-00aSh7; Wed, 20 Feb 2019 12:45:09 +0100 Subject: Re: [PATCH] Btrfs: remove assertion when searching for a key in a node/leaf To: fdmanana@kernel.org, linux-btrfs@vger.kernel.org References: <20190220111143.15911-1-fdmanana@kernel.org> From: Qu Wenruo Openpgp: preference=signencrypt Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAVQEEwEIAD4CGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCWdWCnQUJCWYC bgAKCRDCPZHzoSX+qAR8B/94VAsSNygx1C6dhb1u1Wp1Jr/lfO7QIOK/nf1PF0VpYjTQ2au8 ihf/RApTna31sVjBx3jzlmpy+lDoPdXwbI3Czx1PwDbdhAAjdRbvBmwM6cUWyqD+zjVm4RTG rFTPi3E7828YJ71Vpda2qghOYdnC45xCcjmHh8FwReLzsV2A6FtXsvd87bq6Iw2axOHVUax2 FGSbardMsHrya1dC2jF2R6n0uxaIc1bWGweYsq0LXvLcvjWH+zDgzYCUB0cfb+6Ib/ipSCYp 3i8BevMsTs62MOBmKz7til6Zdz0kkqDdSNOq8LgWGLOwUTqBh71+lqN2XBpTDu1eLZaNbxSI ilaVuQENBFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcga CbPEwhLj1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj /IrRUUka68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fN GSsRb+pKEKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0 q1eW4Jrv0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEv ABEBAAGJATwEGAEIACYWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCWdWBrwIbDAUJA8JnAAAK CRDCPZHzoSX+qA3xB/4zS8zYh3Cbm3FllKz7+RKBw/ETBibFSKedQkbJzRlZhBc+XRwF61mi f0SXSdqKMbM1a98fEg8H5kV6GTo62BzvynVrf/FyT+zWbIVEuuZttMk2gWLIvbmWNyrQnzPl mnjK4AEvZGIt1pk+3+N/CMEfAZH5Aqnp0PaoytRZ/1vtMXNgMxlfNnb96giC3KMR6U0E+siA 4V7biIoyNoaN33t8m5FwEwd2FQDG9dAXWhG13zcm9gnk63BN3wyCQR+X5+jsfBaS4dvNzvQv h8Uq/YGjCoV1ofKYh3WKMY8avjq25nlrhzD/Nto9jHp8niwr21K//pXVA81R2qaXqGbql+zo Message-ID: <83dfeab3-15c0-9c11-bc1b-e4f1f067bd11@gmx.com> Date: Wed, 20 Feb 2019 19:45:04 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.0 MIME-Version: 1.0 In-Reply-To: <20190220111143.15911-1-fdmanana@kernel.org> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="MNOdXjBITTYXz6ZTuwMZSkYF5TnycTywP" X-Provags-ID: V03:K1:281mlC9yMuLIc1BvOBjDgQwBIKXpmcf2PIsSgl4ksKcZYsJmDq4 c5HMWaVOo9HdJFif8ZgM3q/Z1FXI9KS3e+r63SejsO+dMNEInSC16VWzKh3wnjCaHrj0SlU KXfmWs632bqCR+4UHc0SkzKuZKF1MfxMitsJjd3iSHLYhpXVD867EunCtZLFLDSiJv2/NNB N0KHOOfSl98YOryoPI5UQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:Q88jUHfM6Zk=:0dev8bIQHeSc9G9QKoYZMA +yGKgkRY0sh/rUFXdEYcSm4nkvLwhvUQAEzTUJfW2p5tabDDd/oGcjX6n/nFYLp8N8Gcovv20 zbImmhCSImXqJribYaZtuiTG1bX+89q1WaT4WXhNb6tmm9MMZgw7geUN+3+Dj+6mdDn9TNtfO bOViv2lRyPV/h1LpZt8FfRlNm0rsouGZD4s8zIMKkgV+noPHzSdkixcvhOG+S5zEdm5RYQulX Z1Ou/FDe45wF2Xk2QmogpSw4y2NDW9IdwfUbiQTbcMSmAlFoO2LJ9UpMO0hZaa046d7jM8mdA c5AlOGI2T5m2KYfAXvL4NZyPHQWuoRqafURX+IXNedjjJ7IV3Pvng2Qq2PBLuNSj8WJ7JKv1o XXvMWfpZx8M3Un6XduL+a+X2FqluZWbRscjLIltd9Zc0aIpK3uaEXmR1KcujxjuyRqlL6JWyv vmMnal1g09pPBd5U5ajRRjIDzlgKkATAClg1ZsTnOBXll6Kr4/7bDygnJJNcOPdfcicSNgYRP 81YVRSKJX7NgwVkNgnyaCaCLmvM2G4cb27GpUiRKURMGPyggAUjOufe0r7XMBG9i/gcqm6kKd qhehYmlMeE3zxhEIG7fTxuhd80qwhaIuImWAh3oezH2VwrtcnQH4nuAY3+8K3rWjsXp/EquD0 XiGCwTLVNFhBbL96ImfX/9u2NVDNyxPxbqmegWFnsuv+qYNw2cDk+kaTiStSFBNs8VeflziCF Ccb8ERFJmVfxRNuCp8QcYJ850da/fX+33PMgSe2yycQdelo3/+8EsCn3BKldBlqLkZB7kIcoz 7TkMiq7ykfHJm7I55JowGo1RvRAHBM/bzgz4ofcS4b3jUp+LGfyT32athdmL0htyhb8xXx1qw grQAjval/OMT/NHo5/DlZUr82CK/JKzlV3iBguSgTL7ZETrdg4PuXqtwUVIlig Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --MNOdXjBITTYXz6ZTuwMZSkYF5TnycTywP Content-Type: multipart/mixed; boundary="Mmmem6rsAVD1YRmQo61s5rpN9OR60JCyx"; protected-headers="v1" From: Qu Wenruo To: fdmanana@kernel.org, linux-btrfs@vger.kernel.org Message-ID: <83dfeab3-15c0-9c11-bc1b-e4f1f067bd11@gmx.com> Subject: Re: [PATCH] Btrfs: remove assertion when searching for a key in a node/leaf References: <20190220111143.15911-1-fdmanana@kernel.org> In-Reply-To: <20190220111143.15911-1-fdmanana@kernel.org> --Mmmem6rsAVD1YRmQo61s5rpN9OR60JCyx Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2019/2/20 =E4=B8=8B=E5=8D=887:11, fdmanana@kernel.org wrote: > From: Filipe Manana >=20 > At ctree.c:key_search(), the assertion that verifies the first key on a= > child extent buffer corresponds to the key at a specific slot in the > parent has a disadvantage: we effectively hit a BUG_ON() which requires= > rebooting the machine later. It also does not tell any information abou= t > which extent buffer is affected, from which root, the expected and foun= d > keys, etc. >=20 > However as of commit 581c1760415c48 ("btrfs: Validate child tree block'= s > level and first key"), that assertion is not needed since at the time w= e > read an extent buffer from disk we validate that its first key matches = the > key, at the respective slot, in the parent extent buffer. Therefore jus= t > remove the assertion at key_search(). >=20 > Signed-off-by: Filipe Manana Reviewed-by: Qu Wenruo Thanks, Qu > --- > fs/btrfs/ctree.c | 21 --------------------- > 1 file changed, 21 deletions(-) >=20 > diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c > index 5b9f602fb9e2..e754bd019618 100644 > --- a/fs/btrfs/ctree.c > +++ b/fs/btrfs/ctree.c > @@ -2529,26 +2529,6 @@ setup_nodes_for_search(struct btrfs_trans_handle= *trans, > return ret; > } > =20 > -static void key_search_validate(struct extent_buffer *b, > - const struct btrfs_key *key, > - int level) > -{ > -#ifdef CONFIG_BTRFS_ASSERT > - struct btrfs_disk_key disk_key; > - > - btrfs_cpu_key_to_disk(&disk_key, key); > - > - if (level =3D=3D 0) > - ASSERT(!memcmp_extent_buffer(b, &disk_key, > - offsetof(struct btrfs_leaf, items[0].key), > - sizeof(disk_key))); > - else > - ASSERT(!memcmp_extent_buffer(b, &disk_key, > - offsetof(struct btrfs_node, ptrs[0].key), > - sizeof(disk_key))); > -#endif > -} > - > static int key_search(struct extent_buffer *b, const struct btrfs_key = *key, > int level, int *prev_cmp, int *slot) > { > @@ -2557,7 +2537,6 @@ static int key_search(struct extent_buffer *b, co= nst struct btrfs_key *key, > return *prev_cmp; > } > =20 > - key_search_validate(b, key, level); > *slot =3D 0; > =20 > return 0; >=20 --Mmmem6rsAVD1YRmQo61s5rpN9OR60JCyx-- --MNOdXjBITTYXz6ZTuwMZSkYF5TnycTywP Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAlxtPcAACgkQwj2R86El /qiA1Af/YX+sMkDmRHA5Fa1uICQAParrDvKZflT/VGXvnw0ExZTy9VuaFfPwiQOo Qn3CPhDbHyz72UF+QbNsFycJSTttPPcOaEyz1EMcxOkMK2dRIqo5l5axkrBQ8mPu 5+OQ962pkZzJmuth4nFoilxrhxNZPZbrfq9O3MZS3xOY7jWQsyVk6aC9rXTsJoRR W1/VOmG5c7ZGPJBlbKxse3T6RCzWajGWwCStXvH05t2bvDn2/XuxgevvyAwaEdO/ eNgQKDiTuvw2meWNYYPrlM2HVHRAgxba0TQZToJ8o6NozR0k4NBVhsuADzX2bEMb voGUUior5p0deRNgeW4QtTIGIQc1zw== =XEVk -----END PGP SIGNATURE----- --MNOdXjBITTYXz6ZTuwMZSkYF5TnycTywP--