> On May 24, 2024, at 4:59 AM, Jaroslav Pulchart <jaroslav.pulchart@xxxxxxxxxxxx> wrote:
>
>>
>>>
>>> On Wed, May 22, 2024 at 04:36:57AM -0400, Jaroslav Pulchart wrote:
>>>> Hello,
>>>>
>>>> I would like to report some issue causing a "general protection fault"
>>>> crash (constantly) after we updated the kernel from 6.8.9 to 6.8.10.
>>>> This is triggered when monitoring is using nfsstat on a server where
>>>> nfsd is running.
>>>>
>>>> [ 3049.260633] general protection fault, probably for non-canonical
>>>> address 0x66fb103e19e9cc89: 0000 [#1] PREEMPT SMP NOPTI
>>>> [ 3049.261628] CPU: 22 PID: 74991 Comm: nfsstat Tainted: G
>>>> E 6.8.10-1.gdc.el9.x86_64 #1
>>>> [ 3049.262336] Hardware name: RDO OpenStack Compute/RHEL, BIOS
>>>> edk2-20240214-2.el9 02/14/2024
>>>> [ 3049.263003] RIP: 0010:_raw_spin_lock_irqsave+0x19/0x40
>>>> [ 3049.263487] Code: cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
>>>> 90 0f 1f 44 00 00 41 54 9c 41 5c fa 65 ff 05 a6 92 f5 42 31 c0 ba 01
>>>> 00 00 00 <f0> 0f b1 17 75 0a 4c 89 e0 41 5c c3 cc cc cc cc 89 c6 e8 d0
>>>> 07 00
>>>> [ 3049.264882] RSP: 0018:ffffb1bca6b9bd00 EFLAGS: 00010046
>>>> [ 3049.265365] RAX: 0000000000000000 RBX: 66fb103e19e9c989 RCX: 0000000000000001
>>>> [ 3049.265953] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 66fb103e19e9cc89
>>>> [ 3049.266542] RBP: ffffffffc15df280 R08: 0000000000000001 R09: ffffa049a1785cb8
>>>> [ 3049.267112] R10: ffffb1bca6b9bd70 R11: ffffa04964e49000 R12: 0000000000000246
>>>> [ 3049.267702] R13: 66fb103e19e9cc89 R14: ffffa048445590a0 R15: 0000000000000001
>>>> [ 3049.268278] FS: 00007fa3ddf03740(0000) GS:ffffa05703d00000(0000)
>>>> knlGS:0000000000000000
>>>> [ 3049.268928] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>>> [ 3049.269443] CR2: 00007fa3dddfca50 CR3: 0000000342d1e004 CR4: 0000000000770ef0
>>>> [ 3049.270025] PKRU: 55555554
>>>> [ 3049.270371] Call Trace:
>>>> [ 3049.270723] <TASK>
>>>> [ 3049.271035] ? die_addr+0x33/0x90
>>>> [ 3049.271423] ? exc_general_protection+0x1ea/0x450
>>>> [ 3049.271879] ? asm_exc_general_protection+0x22/0x30
>>>> [ 3049.272344] ? _raw_spin_lock_irqsave+0x19/0x40
>>>> [ 3049.272803] __percpu_counter_sum+0xd/0x70
>>>> [ 3049.273219] nfsd_show+0x4f/0x1d0 [nfsd]
>>>> [ 3049.273666] seq_read_iter+0x11d/0x4d0
>>>> [ 3049.274073] ? avc_has_perm+0x42/0xc0
>>>> [ 3049.274489] seq_read+0xfe/0x140
>>>> [ 3049.274866] proc_reg_read+0x56/0xa0
>>>> [ 3049.275257] vfs_read+0xa7/0x340
>>>> [ 3049.275647] ? __do_sys_newfstat+0x57/0x60
>>>> [ 3049.276059] ksys_read+0x5f/0xe0
>>>> [ 3049.276439] do_syscall_64+0x5e/0x170
>>>> [ 3049.276836] entry_SYSCALL_64_after_hwframe+0x78/0x80
>>>> [ 3049.277296] RIP: 0033:0x7fa3ddcfd9b2
>>>> [ 3049.277719] Code: c0 e9 b2 fe ff ff 50 48 8d 3d ea 1d 0c 00 e8 c5
>>>> fd 01 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75
>>>> 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89
>>>> 54 24
>>>> [ 3049.279139] RSP: 002b:00007ffd930672e8 EFLAGS: 00000246 ORIG_RAX:
>>>> 0000000000000000
>>>> [ 3049.279788] RAX: ffffffffffffffda RBX: 0000555ded47c2a0 RCX: 00007fa3ddcfd9b2
>>>> [ 3049.280402] RDX: 0000000000000400 RSI: 0000555ded47c480 RDI: 0000000000000003
>>>> [ 3049.281046] RBP: 00007fa3dddf75e0 R08: 0000000000000003 R09: 0000000000000077
>>>> [ 3049.281673] R10: 000000000000005d R11: 0000000000000246 R12: 0000555ded47c2a0
>>>> [ 3049.282307] R13: 0000000000000d68 R14: 00007fa3dddf69e0 R15: 0000000000000d68
>>>> [ 3049.282928] </TASK>
>>>> [ 3049.283310] Modules linked in: mptcp_diag(E) xsk_diag(E)
>>>> raw_diag(E) unix_diag(E) af_packet_diag(E) netlink_diag(E) udp_diag(E)
>>>> tcp_diag(E) inet_diag(E) tun(E) br_netfilter(E) bridge(E) stp(E)
>>>> llc(E) nfsd(E) auth_rpcgss(E) nfs_acl(E) lockd(E) grace(E) sunrpc(E)
>>>> nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) binfmt_misc(E)
>>>> zram(E) tls(E) isofs(E) vfat(E) fat(E) intel_rapl_msr(E)
>>>> intel_rapl_common(E) kvm_amd(E) ccp(E) kvm(E) irqbypass(E)
>>>> virtio_net(E) i2c_i801(E) virtio_gpu(E) i2c_smbus(E) net_failover(E)
>>>> virtio_balloon(E) failover(E) virtio_dma_buf(E) fuse(E) ext4(E)
>>>> mbcache(E) jbd2(E) sr_mod(E) cdrom(E) sg(E) ahci(E) libahci(E)
>>>> crct10dif_pclmul(E) crc32_pclmul(Ea) polyval_clmulni(E)
>>>> polyval_generic(E) libata(E) ghash_clmulni_intel(E) sha512_ssse3(E)
>>>> virtio_blk(E) serio_raw(E) btrfs(E) xor(E) zstd_compress(E)
>>>> raid6_pq(E) libcrc32c(E) crc32c_intel(E) dm_mirror(E)
>>>> dm_region_hash(E) dm_log(E) dm_mod(E)
>>>> [ 3049.283345] Unloaded tainted modules: edac_mce_amd(E):1 padlock_aes(E)
>>>>
>>>> Any suggestion on how to fix it is appreciated.
>>>
>>> Bisect between v6.8.9 and v6.8.10 would give us the exact point
>>> where the failures were introduced.
>>>
>>> I see that GregKH pulled in:
>>>
>>> 26a0ddb04230 ("nfsd: rename NFSD_NET_* to NFSD_STATS_*")
>>> b7b05f98f3f0 ("nfsd: expose /proc/net/sunrpc/nfsd in net namespaces")
>>> abf5fb593c90 ("nfsd: make all of the nfsd stats per-network namespace")
>>>
>>> for v6.8.10 as a Stable-Dep-of: 18180a4550d0 ("NFSD: Fix nfsd4_encode_fattr4() crasher")
>>>
>>> Which is a little baffling, I don't see how those two change sets
>>> are mechanically related to each other. But I suspect the culprit is
>>> one of those three stat-related patches.
>>>
>>>
>>> --
>>> Chuck Lever
>>
>>
>> Hello,
>>
>> I run bisecting. It was easy to reproduce, simple execution of
>> "nfsstat" from terminal stuck the server:
>>
>> abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566 is the first bad commit
>>
>>
>> $ git bisect bad
>> abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566 is the first bad commit
>> commit abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566 (HEAD)
>> Author: Josef Bacik <josef@xxxxxxxxxxxxxx>
>> Date: Fri Jan 26 10:39:47 2024 -0500
>>
>> nfsd: make all of the nfsd stats per-network namespace
>>
>> [ Upstream commit 4b14885411f74b2b0ce0eb2b39d0fffe54e5ca0d ]
>>
>> We have a global set of counters that we modify for all of the nfsd
>> operations, but now that we're exposing these stats across all network
>> namespaces we need to make the stats also be per-network namespace. We
>> already have some caching stats that are per-network namespace, so move
>> these definitions into the same counter and then adjust all the helpers
>> and users of these stats to provide the appropriate nfsd_net struct so
>> that the stats are maintained for the per-network namespace objects.
>>
>> Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
>> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
>> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
>> Stable-dep-of: 18180a4550d0 ("NFSD: Fix nfsd4_encode_fattr4() crasher")
>> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
>>
>> fs/nfsd/cache.h | 2 --
>> fs/nfsd/netns.h | 17 +++++++++++++++--
>> fs/nfsd/nfs4proc.c | 6 +++---
>> fs/nfsd/nfs4state.c | 3 ++-
>> fs/nfsd/nfscache.c | 36 +++++++-----------------------------
>> fs/nfsd/nfsctl.c | 12 +++---------
>> fs/nfsd/nfsfh.c | 3 ++-
>> fs/nfsd/stats.c | 26 ++++++++++++++------------
>> fs/nfsd/stats.h | 54 +++++++++++++++++++-----------------------------------
>> fs/nfsd/vfs.c | 6 ++++--
>> 10 files changed, 69 insertions(+), 96 deletions(-)
>>
>> $ git bisect log
>> git bisect start
>> # status: waiting for both good and bad commits
>> # good: [f3d61438b613b87afb63118bea6fb18c50ba7a6b] Linux 6.8.9
>> git bisect good f3d61438b613b87afb63118bea6fb18c50ba7a6b
>> # status: waiting for bad commit, 1 good commit known
>> # bad: [a0c69a570e420e86c7569b8c052913213eef2b45] Linux 6.8.10
>> git bisect bad a0c69a570e420e86c7569b8c052913213eef2b45
>> # bad: [4aaed9dbe8acd2b6114458f0498a617283d6275b] hv_netvsc: Don't
>> free decrypted memory
>> git bisect bad 4aaed9dbe8acd2b6114458f0498a617283d6275b
>> # bad: [ee190d04c2f99c8e557b00e997621c04592baed1] net: gro: add flush
>> check in udp_gro_receive_segment
>> git bisect bad ee190d04c2f99c8e557b00e997621c04592baed1
>> # bad: [781e34b736014188ba9e46a71535237313dcda81] efi/unaccepted:
>> touch soft lockup during memory accept
>> git bisect bad 781e34b736014188ba9e46a71535237313dcda81
>> # bad: [6a7b07689af6e4e023404bf69b1230f43b2a15bc] NFSD: Fix
>> nfsd4_encode_fattr4() crasher
>> git bisect bad 6a7b07689af6e4e023404bf69b1230f43b2a15bc
>> # good: [e05194baae299f2148ab5f6bab659c6ce8d1f6d3] nfs: expose
>> /proc/net/sunrpc/nfs in net namespaces
>> git bisect good e05194baae299f2148ab5f6bab659c6ce8d1f6d3
>> # good: [946ab150335d92f852288c1c6b0f0466b5d6e97f] power: supply:
>> mt6360_charger: Fix of_match for usb-otg-vbus regulator
>> git bisect good 946ab150335d92f852288c1c6b0f0466b5d6e97f
>> # good: [b7b05f98f3f06fea3986b46e5c7fe2928676b02d] nfsd: expose
>> /proc/net/sunrpc/nfsd in net namespaces
>> git bisect good b7b05f98f3f06fea3986b46e5c7fe2928676b02d
>> # bad: [0e8003af77879572dbc1df56860cbe2bfa8498f0] NFSD: add support
>> for CB_GETATTR callback
>> git bisect bad 0e8003af77879572dbc1df56860cbe2bfa8498f0
>> # bad: [abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566] nfsd: make all of
>> the nfsd stats per-network namespace
>> git bisect bad abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566
>> # first bad commit: [abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566] nfsd:
>> make all of the nfsd stats per-network namespace
>
> I built a full 6.8.10 with reverted single commit
> "abf5fb593c90d3ab55d6cf1dea7bec8ee0bf3566". The server does not get
> stuck when calling "nfsstat".
Good to know, but I don't think it's entirely safe to revert
only that patch -- all three would have to come off.
I can't seem to get nfsstat to trigger a problem on my
server.
--
Chuck Lever
