From nobody Mon Oct 24 15:41:10 2022 X-Original-To: fs@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4MwznN2GD9z4g1bQ; Mon, 24 Oct 2022 15:41:12 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: from mail-ot1-x329.google.com (mail-ot1-x329.google.com [IPv6:2607:f8b0:4864:20::329]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1D4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4MwznM4rSmz3W4Y; Mon, 24 Oct 2022 15:41:11 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: by mail-ot1-x329.google.com with SMTP id w6-20020a056830110600b00665bf86f012so956003otq.0; Mon, 24 Oct 2022 08:41:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:references:in-reply-to :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=BXpKxykWz9/4+msPwY01RpqkxFtpNqiL+QkrXvH+t98=; b=KeJmHZ6IfYKP/ZN5W2oD/OIJYK92P6jDEEkJNRabhvHrVv5CuwJBSCHcx1PSD3B3OF W0Oj08K9Hu7k7jPLUwvbkTh/0SfkB/V2C25MnrHWthMZA666SpmZW5PSWxL3QD7B8TJ7 SFY2vs28xGjm20evF4Jog1aF5Fy8fafgzbochgVX+E79g9WVZyI4qPyWVhI+UMB1EPV6 AVaz7I4q6BhR+c1LeyTUC6I5HWluVC6Ksjjz2oWBKHaFeLxnaxhr81If8yNSxJxPy3gA zkPOJXVnAf9pcUroJDSlv4d6Jb4tbMulCIBVaSZIoBSkm5Y7REjjShZU5Xo1m8l7yVqe +psg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:references:in-reply-to :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=BXpKxykWz9/4+msPwY01RpqkxFtpNqiL+QkrXvH+t98=; b=0W2oYuxDrG6Cy/EEz9bwUUaAWxw3cMjM5wcYqj8dMJAlN/dbQZZ0EoX3k0QAoy9N5m zIJ01BaZ+1xXYlhQ/N/pR7tL4IRt/WTLfHpZQfSzy3QP5KAXRxyCkWE/ci2MLhorEOvd Rv9qtAOuBba19Z8RyBqz+avxzFRTh447riMzm0uHbGUig8YcD3aKXdyBrAIQOI+E5H3e b35Cw1c2mT7TpdoVu1LPLNiw23JhoTx8yIf1Z6sSw3ZGHiVtbuBhFulu8LziTnKQWstY eaSIZEJJLR1sPjL7IHm0qn+rk12Hqk2QXAyo+RTeFysBw/x/A35nDz+t/rE/isyZMoRM VJdA== X-Gm-Message-State: ACrzQf2f6azS88WTGsVhz9BDDpW/WMt92eJMEKxlwTD29J9JrWn7JrRD 7NJH8qpp+eJURA4NMjIZXZGKrIyjhyAOJFbOYwNAP6eY X-Google-Smtp-Source: AMsMyM7rGNkumkNgQcrIZ3rZJ8fxes2Wf5AEbs2AuelP+e0wvJxF2mrBc4aPghXypTVRxrfafm4+Nu3vza5tOv1v3fA= X-Received: by 2002:a9d:7458:0:b0:662:1044:791c with SMTP id p24-20020a9d7458000000b006621044791cmr11537125otk.281.1666626070857; Mon, 24 Oct 2022 08:41:10 -0700 (PDT) List-Id: Filesystems List-Archive: https://lists.freebsd.org/archives/freebsd-fs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-fs@freebsd.org MIME-Version: 1.0 Received: by 2002:a8a:351:0:b0:478:5e54:a9c8 with HTTP; Mon, 24 Oct 2022 08:41:10 -0700 (PDT) In-Reply-To: <2f586acb-a8ee-fa17-bbbb-740f41dbfe82@FreeBSD.org> References: <93085f3c-4592-8f46-fadb-ba0ee2d2ffa9@FreeBSD.org> <2f586acb-a8ee-fa17-bbbb-740f41dbfe82@FreeBSD.org> From: Mateusz Guzik Date: Mon, 24 Oct 2022 17:41:10 +0200 Message-ID: Subject: Re: panic: condition seqc_in_modify not met, while replaying ZIL To: Andriy Gapon Cc: freebsd-stable List , freebsd-fs Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 4MwznM4rSmz3W4Y X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20210112 header.b=KeJmHZ6I; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (mx1.freebsd.org: domain of mjguzik@gmail.com designates 2607:f8b0:4864:20::329 as permitted sender) smtp.mailfrom=mjguzik@gmail.com X-Spamd-Result: default: False [-3.66 / 15.00]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-1.00)[-0.999]; NEURAL_HAM_MEDIUM(-0.66)[-0.660]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20210112]; R_SPF_ALLOW(-0.20)[+ip6:2607:f8b0:4000::/36:c]; MIME_GOOD(-0.10)[text/plain]; MLMMJ_DEST(0.00)[stable@freebsd.org,fs@freebsd.org]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_ENVFROM(0.00)[gmail.com]; RCVD_IN_DNSWL_NONE(0.00)[2607:f8b0:4864:20::329:from]; ASN(0.00)[asn:15169, ipnet:2607:f8b0::/32, country:US]; ARC_NA(0.00)[]; MID_RHS_MATCH_FROMTLD(0.00)[]; TO_DN_ALL(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; FROM_HAS_DN(0.00)[]; DKIM_TRACE(0.00)[gmail.com:+]; FREEMAIL_FROM(0.00)[gmail.com]; RCVD_COUNT_THREE(0.00)[3]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_TLS_LAST(0.00)[]; DWL_DNSWL_NONE(0.00)[gmail.com:dkim] X-ThisMailContainsUnwantedMimeParts: N On 10/24/22, Andriy Gapon wrote: > On 20/10/2022 17:32, Mateusz Guzik wrote: >> This is a false-positive -- the seqc stuff is not modified on replay >> and zfs internal asserts check for it. I think the easiest way forward >> for this one is to appease the assert by entering it seqc. >> >> That said, could it be it is an invariant there are no nc entries at >> this stage anyway and the call to cache_vop_rmdir can be avoided? I >> can add cache_assert_no_entries or similar routine to be called >> instead. > > I've checked the code and, indeed, the name cache is doubly disabled while > ZIL > is replayed. ZFS sets z_use_namecache to false and z_replay to true before > the > replay. And either is sufficient to disable ZFS name cache calls (which is > > redundant, but that's a different topic). > > So, I came up with this small proof-of-concept patch (and it helped with the > > problem at hand). > It does not assert that the name cache for the filesystem being mounted is > actually empty. That would be a good addition, if you wish to add it. > > diff --git a/sys/contrib/openzfs/module/os/freebsd/zfs/zfs_vnops_os.c > b/sys/contrib/openzfs/module/os/freebsd/zfs/zfs_vnops_os.c > index f6bc9c0c6afb..87fa271dfd5c 100644 > --- a/sys/contrib/openzfs/module/os/freebsd/zfs/zfs_vnops_os.c > +++ b/sys/contrib/openzfs/module/os/freebsd/zfs/zfs_vnops_os.c > @@ -1622,7 +1622,8 @@ zfs_rmdir_(vnode_t *dvp, vnode_t *vp, const char > *name, > cred_t *cr) > > dmu_tx_commit(tx); > > - cache_vop_rmdir(dvp, vp); > + if (zfsvfs->z_use_namecache) > + cache_vop_rmdir(dvp, vp); > out: > if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS) > zil_commit(zilog, 0); > Added the routine in https://cgit.FreeBSD.org/src/commit/?id=d653aaec7a311a7d1455e9721904b2a341b32a65, just call it for the else clause. > > >> On 10/20/22, Andriy Gapon wrote: >>> >>> This happens on stable/13, custom kernel compiled with DEBUG_VFS_LOCKS, >>> from >>> >>> mid-September after an ungraceful reboot (unrelated crash). As far as I >>> can >>> see >>> in kgdb, both dvp and vp have v_seqc == 0. >>> >>> VNASSERT failed: ({ seqc_t __seqc = (_vp->v_seqc); >>> __builtin_expect((__seqc >>> & >>> 1), 0); }) not true at >>> /usr/home/avg/devel/freebsd-src-new/machines/trant/sys/kern/vfs_cache.c:2976 >>> >>> (cache_vop_rmdir) >>> 0xfffff8004bc0bd58: type VDIR >>> usecount 1, writecount 0, refcount 1 seqc users 0 mountedhere 0 >>> hold count flags () >>> flags () >>> lock type zfs: UNLOCKED >>> panic: condition seqc_in_modify(_vp->v_seqc) not met at >>> /usr/home/avg/devel/freebsd-src-new/machines/trant/sys/kern/vfs_cache.c:2976 >>> >>> (cache_vop_rmdir) >>> cpuid = 5 >>> time = 1666250711 >>> KDB: stack backtrace: >>> db_trace_self_wrapper() at 0xffffffff8061549b = >>> db_trace_self_wrapper+0x2b/frame >>> 0xfffffe01ce6c7090 >>> kdb_backtrace() at 0xffffffff80942927 = kdb_backtrace+0x37/frame >>> 0xfffffe01ce6c7140 >>> vpanic() at 0xffffffff808f4fb4 = vpanic+0x184/frame 0xfffffe01ce6c71a0 >>> panic() at 0xffffffff808f4d63 = panic+0x43/frame 0xfffffe01ce6c7200 >>> cache_vop_rmdir() at 0xffffffff809b9b9f = cache_vop_rmdir+0xdf/frame >>> 0xfffffe01ce6c7220 >>> zfs_rmdir_() at 0xffffffff80391cff = zfs_rmdir_+0x1df/frame >>> 0xfffffe01ce6c7290 >>> zfs_rmdir() at 0xffffffff80391af8 = zfs_rmdir+0x48/frame >>> 0xfffffe01ce6c7310 >>> zfs_replay_remove() at 0xffffffff804fc53b = zfs_replay_remove+0x7b/frame >>> 0xfffffe01ce6c7340 >>> zil_replay_log_record() at 0xffffffff80508462 = >>> zil_replay_log_record+0x212/frame 0xfffffe01ce6c7490 >>> zil_parse() at 0xffffffff80502f4b = zil_parse+0x5cb/frame >>> 0xfffffe01ce6c76a0 >>> zil_replay() at 0xffffffff805081d8 = zil_replay+0xd8/frame >>> 0xfffffe01ce6c7700 >>> zfsvfs_setup() at 0xffffffff8038f09d = zfsvfs_setup+0x24d/frame >>> 0xfffffe01ce6c7930 >>> zfs_mount() at 0xffffffff8038c9b2 = zfs_mount+0x652/frame >>> 0xfffffe01ce6c7ad0 >>> vfs_domount_first() at 0xffffffff809d0d66 = >>> vfs_domount_first+0x216/frame >>> 0xfffffe01ce6c7c00 >>> vfs_domount() at 0xffffffff809cdd43 = vfs_domount+0x2d3/frame >>> 0xfffffe01ce6c7d30 >>> vfs_donmount() at 0xffffffff809ccb6f = vfs_donmount+0x81f/frame >>> 0xfffffe01ce6c7dc0 >>> sys_nmount() at 0xffffffff809cc318 = sys_nmount+0x108/frame >>> 0xfffffe01ce6c7df0 >>> amd64_syscall() at 0xffffffff80c31d16 = amd64_syscall+0x186/frame >>> 0xfffffe01ce6c7f30 >>> fast_syscall_common() at 0xffffffff80c0889b = >>> fast_syscall_common+0xf8/frame >>> >>> 0xfffffe01ce6c7f30 >>> --- syscall (378, FreeBSD ELF64, sys_nmount), rip = 0xb6aac9dd1a, rsp = >>> 0xb6b538f468, rbp = 0xb6b538f4d0 --- >>> Uptime: 37s >>> Dumping 1426 out of 32644 MB: (CTRL-C to abort) >>> ..2%..11%..21%..31%..41%..51%..61%..71%..81%..91% >>> >>> -- >>> Andriy Gapon >>> >> >> > > -- > Andriy Gapon > > -- Mateusz Guzik