From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yx2-f32.google.com (mail-yx2-f32.google.com [74.125.224.160]) (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 A203B32FA18 for ; Tue, 29 Sep 2026 23:38:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.224.160 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790725097; cv=none; b=PQAwJaKyEsTXajHvMcb6RVZkpuSkFXVZxmcMWX9KnmWeWIlgaDkWYrUhN9fYW5ilcUV0MvTMLqrYQvgSLlwG6DI7MNqoYK7NRPz910GTe3DQOsrSTFIiWKUNgbUiHDYVY8aNvmTANQFCdwtBQxu+36Lrz7Zrr67WAYYk2JQpZf4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790725097; c=relaxed/simple; bh=I10odQRrWnIIn1oMgCfshWxiTUJPuqRyQuPjXs1+oBw=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=dpqWSsAzrvv9GySFrvTaa1f7Js8nZJ3mViF41dNS1BSYM4+YmlIHjwCtB8bhxLENNcyQifvCLhFfY5xHNeSQ8owi/Jv48GMju4W/JN2FdEaBdnRkJQ6JGxgVRZER0NDhr0LOTnbrCqS3as2PG7eEts8Vt1OOBMWt+pgyjr+zIPk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=dubeyko.com; spf=pass smtp.mailfrom=dubeyko.com; dkim=pass (2048-bit key) header.d=dubeyko-com.20251104.gappssmtp.com header.i=@dubeyko-com.20251104.gappssmtp.com header.b=Ymho02HO; arc=none smtp.client-ip=74.125.224.160 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=dubeyko.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=dubeyko.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=dubeyko-com.20251104.gappssmtp.com header.i=@dubeyko-com.20251104.gappssmtp.com header.b="Ymho02HO" Received: by mail-yx2-f32.google.com with SMTP id 00721157ae682-8ac4967f1c9so1031327b3.2 for ; Tue, 29 Sep 2026 16:38:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dubeyko-com.20251104.gappssmtp.com; s=20251104; t=1790725094; x=1791329894; darn=vger.kernel.org; h=mime-version:user-agent:content-transfer-encoding:content-type :autocrypt:references:in-reply-to:date:cc:to:from:subject:message-id :from:to:cc:subject:date:message-id:reply-to:content-type; bh=ZXqJLVCbZu2yjIdVQWm337W+r0cqf+6Xh9H+ELjQb10=; b=Ymho02HOM0IMUoQ9ne8LFI367zynZK57ydIabwAaLO+1+vrDlgZ01lEY1oq52aLL4i ZLFOisI774dSlXfuSRj+q2J4uig/voOu26DIVg6J+emWnfpNslZR9I6WOKEgNVAfodPQ njDui4pvqRrMdD5CPhJKpR04BVcIuoLmLiq7jrE2DiJwERHgvuGjr78Sbeq7jR/3YVam yVv2M99XYpUPx4eYWB8eG80OowzA5N9QxxxfTc4V97F5uf4FcgR/zcBct3VwSDvkCLQd 8hd1saKKgc403W2sAsD5VsGmr//VEp8YgmVQ0yNC3Nj35lsyGCLTeN2GmiTsTS2cdFCw a7PA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790725094; x=1791329894; h=mime-version:user-agent:content-transfer-encoding:content-type :autocrypt:references:in-reply-to:date:cc:to:from:subject:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=ZXqJLVCbZu2yjIdVQWm337W+r0cqf+6Xh9H+ELjQb10=; b=OTR9J/t+PIHBlr0T/ilG/UpJIQrxVW7v6azsy7BBVhqJavTvhU5jfBVR0sNDm5+Dce LZzMx+jSDbyxcgpsxl1YlXiioWo4nxYwFHNbwsHmcQtfXi6qWL6zqFclDQOtFzH3vMVy d1pefuYVekXATeoX9x042t5Ms1r+s7xQ+h709HbmY0urYn0lqE91LhpGINwrG1ocJQo2 +iINV/TyhF0IoTxsrdQFqAekisSRB8g1SKkdmeKq8Fwr+NyvOyDfLYuv3hIxmeHGVY4m YLLOQarc9QmfCUlIynuREEMgXtU4TR8ddl5/BGSZ2aRTvt+aUTyouXeuCXXoZG7UGPp6 IeqA== X-Forwarded-Encrypted: i=1; AKwUvByGlQeqmjmBTzZCrIlTs7V1srIGdzbBg6pm7Yx3jGc0wlM8CJi+KEfl55ZFYIp54MCRMF88BsqxPXzuDoU=@vger.kernel.org X-Gm-Message-State: AFq9FYIzvt6sx+kNFFGCFurTZD5g/wjjREyPjXXNipAUdAkeBSFgT9Yo fMsOt7KwMo/fc46jWjaasWU7HxSlqt6f93jk55fMxxRAJMEKVe9aP9ApEdShJiatjY/dmXgTKqy iuKoujio= X-Gm-Gg: AYBFou2eugP5nj0ga/CaRZ35rpIw5CUdZN9f5rG5oaTzdsMJsSygBIbqJK2B8D/6opg Z5PGIG3PiyRVnxBMWbNIPOHn4q/EIezxBVqF9tqrDTiPAz27rzmwYW/SjQo7qS/pBiGvDAI1trH NQr7qDyiF2f0TepE86swW+vhucROVBUFmfktxlEdWiiw8uTy6iZzhsMgsTiQn9lXXLL0BmmQRzd hLnoCkgF5HEONE6XaQ0txI/mkiwsJDjVeu7HscCGWgk8QDtWw69fJXr4EsyteUxik0QV+J7YgIT ICEMY/Dcn/7C61Pj6lhGneULEq7USW1KlycJ2U4PLBp/f3ODCfwAKliwXDENZd1HV/XAmW5ZchI uDIbtigcazxKhSxcpb7LGpPSWDFt2lX2JrwSINI3/ETGh64VO8lttoB0152Tx6scoU1Picw04F0 dVz1jvoogin6piEOJiVDVdmrCa3h8+AkVCEWZsFOEKH9l9+qWI5Tmsa14PYTGJP+TpHXWlsfHAS WJXd55blgLd9U8wBpBSb+3c+YJZ9w+uzPe8/zFwgQll5vtptuMbuc+6GVARTrIHN67wN2ppPTse mA2EzQ7gnQ7TzNFFtV/xQYdcIKLMvVDxyh0gCShLxGKyorwHPOmFZsi3Jx4t0sR9avsKjSum X-Received: by 2002:a05:690e:4807:b0:674:aae3:8527 with SMTP id 956f58d0204a3-6764407ab2amr143773d50.48.1790725094493; Tue, 29 Sep 2026 16:38:14 -0700 (PDT) Received: from ?IPv6:2600:1700:6476:1430:ace4:86e:1afc:3c4e? ([2600:1700:6476:1430:ace4:86e:1afc:3c4e]) by smtp.gmail.com with ESMTPSA id 956f58d0204a3-6768082ec26sm53253d50.0.2026.09.29.16.38.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Sep 2026 16:38:13 -0700 (PDT) Message-ID: Subject: Re: [PATCH] nilfs2: ignore non-fatal signals during synchronous log write wait From: Viacheslav Dubeyko To: Ryusuke Konishi Cc: linux-nilfs , LKML , Wang Jianjian , syzbot+f6c7e1f1809f235eeb90@syzkaller.appspotmail.com, syzkaller-bugs@googlegroups.com Date: Tue, 29 Sep 2026 16:38:08 -0700 In-Reply-To: <20260929182954.109470-1-konishi.ryusuke@gmail.com> References: <20260929182954.109470-1-konishi.ryusuke@gmail.com> Autocrypt: addr=slava@dubeyko.com; prefer-encrypt=mutual; keydata=mQINBGgaTLYBEADaJc/WqWTeunGetXyyGJ5Za7b23M/ozuDCWCp+yWUa2GqQKH40dxRIR zshgOmAue7t9RQJU9lxZ4ZHWbi1Hzz85+0omefEdAKFmxTO6+CYV0g/sapU0wPJws3sC2Pbda9/eJ ZcvScAX2n/PlhpTnzJKf3JkHh3nM1ACO3jzSe2/muSQJvqMLG2D71ccekr1RyUh8V+OZdrPtfkDam V6GOT6IvyE+d+55fzmo20nJKecvbyvdikWwZvjjCENsG9qOf3TcCJ9DDYwjyYe1To8b+mQM9nHcxp jUsUuH074BhISFwt99/htZdSgp4csiGeXr8f9BEotRB6+kjMBHaiJ6B7BIlDmlffyR4f3oR/5hxgy dvIxMocqyc03xVyM6tA4ZrshKkwDgZIFEKkx37ec22ZJczNwGywKQW2TGXUTZVbdooiG4tXbRBLxe ga/NTZ52ZdEkSxAUGw/l0y0InTtdDIWvfUT+WXtQcEPRBE6HHhoeFehLzWL/o7w5Hog+0hXhNjqte fzKpI2fWmYzoIb6ueNmE/8sP9fWXo6Av9m8B5hRvF/hVWfEysr/2LSqN+xjt9NEbg8WNRMLy/Y0MS p5fgf9pmGF78waFiBvgZIQNuQnHrM+0BmYOhR0JKoHjt7r5wLyNiKFc8b7xXndyCDYfniO3ljbr0j tXWRGxx4to6FwARAQABtCZWaWFjaGVzbGF2IER1YmV5a28gPHNsYXZhQGR1YmV5a28uY29tPokCVw QTAQoAQQIbAQUJA8JnAAULCQgHAgYVCgkICwIEFgIDAQIeAQIXgBYhBFXDC2tnzsoLQtrbBDlc2cL fhEB1BQJoGl5PAhkBAAoJEDlc2cLfhEB17DsP/jy/Dx19MtxWOniPqpQf2s65enkDZuMIQ94jSg7B F2qTKIbNR9SmsczjyjC+/J7m7WZRmcqnwFYMOyNfh12aF2WhjT7p5xEAbvfGVYwUpUrg/lcacdT0D Yk61GGc5ZB89OAWHLr0FJjI54bd7kn7E/JRQF4dqNsxU8qcPXQ0wLHxTHUPZu/w5Zu/cO+lQ3H0Pj pSEGaTAh+tBYGSvQ4YPYBcV8+qjTxzeNwkw4ARza8EjTwWKP2jWAfA/ay4VobRfqNQ2zLoo84qDtN Uxe0zPE2wobIXELWkbuW/6hoQFPpMlJWz+mbvVms57NAA1HO8F5c1SLFaJ6dN0AQbxrHi45/cQXla 9hSEOJjxcEnJG/ZmcomYHFneM9K1p1K6HcGajiY2BFWkVet9vuHygkLWXVYZ0lr1paLFR52S7T+cf 6dkxOqu1ZiRegvFoyzBUzlLh/elgp3tWUfG2VmJD3lGpB3m5ZhwQ3rFpK8A7cKzgKjwPp61Me0o9z HX53THoG+QG+o0nnIKK7M8+coToTSyznYoq9C3eKeM/J97x9+h9tbizaeUQvWzQOgG8myUJ5u5Dr4 6tv9KXrOJy0iy/dcyreMYV5lwODaFfOeA4Lbnn5vRn9OjuMg1PFhCi3yMI4lA4umXFw0V2/OI5rgW BQELhfvW6mxkihkl6KLZX8m1zcHitCpWaWFjaGVzbGF2IER1YmV5a28gPFNsYXZhLkR1YmV5a29Aa WJtLmNvbT6JAlQEEwEKAD4WIQRVwwtrZ87KC0La2wQ5XNnC34RAdQUCaBpd7AIbAQUJA8JnAAULCQ gHAgYVCgkICwIEFgIDAQIeAQIXgAAKCRA5XNnC34RAdYjFEACiWBEybMt1xjRbEgaZ3UP5i2bSway DwYDvgWW5EbRP7JcqOcZ2vkJwrK3gsqC3FKpjOPh7ecE0I4vrabH1Qobe2N8B2Y396z24mGnkTBbb 16Uz3PC93nFN1BA0wuOjlr1/oOTy5gBY563vybhnXPfSEUcXRd28jI7z8tRyzXh2tL8ZLdv1u4vQ8 E0O7lVJ55p9yGxbwgb5vXU4T2irqRKLxRvU80rZIXoEM7zLf5r7RaRxgwjTKdu6rYMUOfoyEQQZTD 4Xg9YE/X8pZzcbYFs4IlscyK6cXU0pjwr2ssjearOLLDJ7ygvfOiOuCZL+6zHRunLwq2JH/RmwuLV mWWSbgosZD6c5+wu6DxV15y7zZaR3NFPOR5ErpCFUorKzBO1nA4dwOAbNym9OGkhRgLAyxwpea0V0 ZlStfp0kfVaSZYo7PXd8Bbtyjali0niBjPpEVZdgtVUpBlPr97jBYZ+L5GF3hd6WJFbEYgj+5Af7C UjbX9DHweGQ/tdXWRnJHRzorxzjOS3003ddRnPtQDDN3Z/XzdAZwQAs0RqqXrTeeJrLppFUbAP+HZ TyOLVJcAAlVQROoq8PbM3ZKIaOygjj6Yw0emJi1D9OsN2UKjoe4W185vamFWX4Ba41jmCPrYJWAWH fAMjjkInIPg7RLGs8FiwxfcpkILP0YbVWHiNAabQoVmlhY2hlc2xhdiBEdWJleWtvIDx2ZHViZXlr b0BrZXJuZWwub3JnPokCVAQTAQoAPhYhBFXDC2tnzsoLQtrbBDlc2cLfhEB1BQJoVemuAhsBBQkDw mcABQsJCAcCBhUKCQgLAgQWAgMBAh4BAheAAAoJEDlc2cLfhEB1GRwP/1scX5HO9Sk7dRicLD/fxo ipwEs+UbeA0/TM8OQfdRI4C/tFBYbQCR7lD05dfq8VsYLEyrgeLqP/iRhabLky8LTaEdwoAqPDc/O 9HRffx/faJZqkKc1dZryjqS6b8NExhKOVWmDqN357+Cl/H4hT9wnvjCj1YEqXIxSd/2Pc8+yw/KRC AP7jtRzXHcc/49Lpz/NU5irScusxy2GLKa5o/13jFK3F1fWX1wsOJF8NlTx3rLtBy4GWHITwkBmu8 zI4qcJGp7eudI0l4xmIKKQWanEhVdzBm5UnfyLIa7gQ2T48UbxJlWnMhLxMPrxgtC4Kos1G3zovEy Ep+fJN7D1pwN9aR36jVKvRsX7V4leIDWGzCdfw1FGWkMUfrRwgIl6i3wgqcCP6r9YSWVQYXdmwdMu 1RFLC44iF9340S0hw9+30yGP8TWwd1mm8V/+zsdDAFAoAwisi5QLLkQnEsJSgLzJ9daAsE8KjMthv hUWHdpiUSjyCpigT+KPl9YunZhyrC1jZXERCDPCQVYgaPt+Xbhdjcem/ykv8UVIDAGVXjuk4OW8la nf8SP+uxkTTDKcPHOa5rYRaeNj7T/NClRSd4z6aV3F6pKEJnEGvv/DFMXtSHlbylhyiGKN2Amd0b4 9jg+DW85oNN7q2UYzYuPwkHsFFq5iyF1QggiwYYTpoVXsw Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.1 (by Flathub.org) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Wed, 2026-09-30 at 03:26 +0900, Ryusuke Konishi wrote: > Based on a syzbot report, Wang Jianjian pointed out that following a > successful directory operation in nilfs_rename(), a synchronous write > requested within nilfs_transaction_commit(), triggered by a sync flag > set by nilfs_commit_chunk(), could be interrupted by a user signal. > This interruption leaves in-memory metadata updates intact while > returning an error, causing inconsistency with the VFS dentry cache > and > ultimately triggering a kernel warning. >=20 > According to "signal(7)", local disks are not classified as "slow > devices" (such as terminals, FIFOs, or pipes) and their I/O > operations > on disk devices are not interrupted by signals.=C2=A0 In kernel space, > waiting for such disk I/O should therefore not be aborted by ordinary > (non-fatal) signals. >=20 > Suppress this issue by modifying nilfs_segctor_sync(), which waits > for > the log writer thread to complete synchronous writes, to catch only > fatal signals via fatal_signal_pending() and return -EINTR rather > than > -ERESTARTSYS.=C2=A0 To complement this change and prevent the wait loop > from > busy-looping when schedule() returns immediately due to a pending > non-fatal signal, switch the wait state from TASK_INTERRUPTIBLE to > TASK_KILLABLE. >=20 > This serves as an effective interim stabilization measure without > structural changes until a comprehensive fix for metadata consistency > is implemented. >=20 > Reported-by: syzbot+f6c7e1f1809f235eeb90@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=3Df6c7e1f1809f235eeb90 > Fixes: 9ff05123e3bf ("nilfs2: segment constructor") > Tested-by: syzbot+f6c7e1f1809f235eeb90@syzkaller.appspotmail.com > Cc: Wang Jianjian > Cc: stable@vger.kernel.org > Signed-off-by: Ryusuke Konishi > --- > Hi Viacheslav, >=20 > Please queue this for the next cycle. >=20 > This is the first step toward addressing the state inconsistencies > during directory operations reported by syzbot or on the mailing > lists. > It improves stability by preventing errors caused by user interrupts > while waiting for log writes, which are triggered by synchronous > write > flags following operations such as rename(). >=20 > As this does not fully address the underlying issues in error > handling, > I intend to continue exploring changes that allow directory > operations > to be properly canceled or rolled back. >=20 > Thanks, > Ryusuke Konishi >=20 > =C2=A0fs/nilfs2/ioctl.c=C2=A0=C2=A0=C2=A0 |=C2=A0 2 +- > =C2=A0fs/nilfs2/recovery.c |=C2=A0 2 +- > =C2=A0fs/nilfs2/segment.c=C2=A0 | 10 +++++----- > =C2=A03 files changed, 7 insertions(+), 7 deletions(-) >=20 > diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c > index 01a04080ef70..b2b67d6a1f09 100644 > --- a/fs/nilfs2/ioctl.c > +++ b/fs/nilfs2/ioctl.c > @@ -965,10 +965,10 @@ static int nilfs_ioctl_clean_segments(struct > inode *inode, struct file *filp, > =C2=A0 * Return: 0 on success, or one of the following negative error > codes on > =C2=A0 * failure: > =C2=A0 * * %-EFAULT - Failure during execution of requested > operation. > + * * %-EINTR - Interrupted. > =C2=A0 * * %-EIO - I/O error. > =C2=A0 * * %-ENOMEM - Insufficient memory available. > =C2=A0 * * %-ENOSPC - No space left on device (only in a panic > state). > - * * %-ERESTARTSYS - Interrupted. > =C2=A0 * * %-EROFS - Read only filesystem. > =C2=A0 */ > =C2=A0static int nilfs_ioctl_sync(struct inode *inode, struct file *filp, > diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c > index 9a70c28ec94c..abe4101f7550 100644 > --- a/fs/nilfs2/recovery.c > +++ b/fs/nilfs2/recovery.c > @@ -790,11 +790,11 @@ static void nilfs_abort_roll_forward(struct > the_nilfs *nilfs) > =C2=A0 * > =C2=A0 * Return: 0 on success, or one of the following negative error > codes on > =C2=A0 * failure: > + * * %-EINTR - Interrupted. > =C2=A0 * * %-EINVAL - Inconsistent filesystem state. > =C2=A0 * * %-EIO - I/O error. > =C2=A0 * * %-ENOMEM - Insufficient memory available. > =C2=A0 * * %-ENOSPC - No space left on device (only in a panic > state). > - * * %-ERESTARTSYS - Interrupted. > =C2=A0 */ > =C2=A0int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, > =C2=A0 =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 struct super_block *sb, > diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c > index 2f0e59847d02..af0c3560444f 100644 > --- a/fs/nilfs2/segment.c > +++ b/fs/nilfs2/segment.c > @@ -2259,7 +2259,7 @@ static int nilfs_segctor_sync(struct > nilfs_sc_info *sci) > =C2=A0 wake_up(&sci->sc_wait_daemon); > =C2=A0 > =C2=A0 for (;;) { > - set_current_state(TASK_INTERRUPTIBLE); > + set_current_state(TASK_KILLABLE); > =C2=A0 > =C2=A0 /* > =C2=A0 * Synchronize only while the log writer thread is > alive. > @@ -2273,11 +2273,11 @@ static int nilfs_segctor_sync(struct > nilfs_sc_info *sci) > =C2=A0 err =3D wait_req.err; > =C2=A0 break; > =C2=A0 } > - if (!signal_pending(current)) { > + if (!fatal_signal_pending(current)) { > =C2=A0 schedule(); > =C2=A0 continue; > =C2=A0 } > - err =3D -ERESTARTSYS; > + err =3D -EINTR; > =C2=A0 break; > =C2=A0 } > =C2=A0 finish_wait(&sci->sc_wait_request, &wait_req.wq); > @@ -2311,10 +2311,10 @@ static void nilfs_segctor_wakeup(struct > nilfs_sc_info *sci, int err, bool force) > =C2=A0 * > =C2=A0 * Return: 0 on success, or one of the following negative error > codes on > =C2=A0 * failure: > + * * %-EINTR - Interrupted. > =C2=A0 * * %-EIO - I/O error (including metadata corruption). > =C2=A0 * * %-ENOMEM - Insufficient memory available. > =C2=A0 * * %-ENOSPC - No space left on device (only in a panic > state). > - * * %-ERESTARTSYS - Interrupted. > =C2=A0 * * %-EROFS - Read only filesystem. > =C2=A0 */ > =C2=A0int nilfs_construct_segment(struct super_block *sb) > @@ -2341,10 +2341,10 @@ int nilfs_construct_segment(struct > super_block *sb) > =C2=A0 * > =C2=A0 * Return: 0 on success, or one of the following negative error > codes on > =C2=A0 * failure: > + * * %-EINTR - Interrupted. > =C2=A0 * * %-EIO - I/O error (including metadata corruption). > =C2=A0 * * %-ENOMEM - Insufficient memory available. > =C2=A0 * * %-ENOSPC - No space left on device (only in a panic > state). > - * * %-ERESTARTSYS - Interrupted. > =C2=A0 * * %-EROFS - Read only filesystem. > =C2=A0 */ > =C2=A0int nilfs_construct_dsync_segment(struct super_block *sb, struct > inode *inode, Applied. Thanks, Slava.