| Age | Commit message (Collapse) | Author | Files | Lines |
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Each EMAD transaction stores the skb used to issue the EMAD request
('trans->tx_skb') so that the request could be retried in case of a
timeout. The skb can be freed when a corresponding response is received
or as part of the retry logic (e.g., failed retransmit, exceeded maximum
number of retries).
The two tasks (i.e., response processing and retransmits) are
synchronized by the atomic 'trans->active' field which ensures that
responses to inactive transactions are ignored.
In case of a failed retransmit the transaction is finished and all of
its resources are freed. However, the current code does not mark it as
inactive. Syzkaller was able to hit a race condition in which a
concurrent response is processed while the transaction's resources are
being freed, resulting in a use-after-free [1].
Fix the issue by making sure to mark the transaction as inactive after a
failed retransmit and free its resources only if a concurrent task did
not already do that.
[1]
BUG: KASAN: use-after-free in consume_skb+0x30/0x370
net/core/skbuff.c:833
Read of size 4 at addr ffff88804f570494 by task syz-executor.0/1004
CPU: 0 PID: 1004 Comm: syz-executor.0 Not tainted 5.8.0-rc7+ #68
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xf6/0x16e lib/dump_stack.c:118
print_address_description.constprop.0+0x1c/0x250
mm/kasan/report.c:383
__kasan_report mm/kasan/report.c:513 [inline]
kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
check_memory_region_inline mm/kasan/generic.c:186 [inline]
check_memory_region+0x14e/0x1b0 mm/kasan/generic.c:192
instrument_atomic_read include/linux/instrumented.h:56 [inline]
atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
refcount_read include/linux/refcount.h:147 [inline]
skb_unref include/linux/skbuff.h:1044 [inline]
consume_skb+0x30/0x370 net/core/skbuff.c:833
mlxsw_emad_trans_finish+0x64/0x1c0 drivers/net/ethernet/mellanox/mlxsw/core.c:592
mlxsw_emad_process_response drivers/net/ethernet/mellanox/mlxsw/core.c:651 [inline]
mlxsw_emad_rx_listener_func+0x5c9/0xac0 drivers/net/ethernet/mellanox/mlxsw/core.c:672
mlxsw_core_skb_receive+0x4df/0x770 drivers/net/ethernet/mellanox/mlxsw/core.c:2063
mlxsw_pci_cqe_rdq_handle drivers/net/ethernet/mellanox/mlxsw/pci.c:595 [inline]
mlxsw_pci_cq_tasklet+0x12a6/0x2520 drivers/net/ethernet/mellanox/mlxsw/pci.c:651
tasklet_action_common.isra.0+0x13f/0x3e0 kernel/softirq.c:550
__do_softirq+0x223/0x964 kernel/softirq.c:292
asm_call_on_stack+0x12/0x20 arch/x86/entry/entry_64.S:711
Allocated by task 1006:
save_stack+0x1b/0x40 mm/kasan/common.c:48
set_track mm/kasan/common.c:56 [inline]
__kasan_kmalloc mm/kasan/common.c:494 [inline]
__kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:467
slab_post_alloc_hook mm/slab.h:586 [inline]
slab_alloc_node mm/slub.c:2824 [inline]
slab_alloc mm/slub.c:2832 [inline]
kmem_cache_alloc+0xcd/0x2e0 mm/slub.c:2837
__build_skb+0x21/0x60 net/core/skbuff.c:311
__netdev_alloc_skb+0x1e2/0x360 net/core/skbuff.c:464
netdev_alloc_skb include/linux/skbuff.h:2810 [inline]
mlxsw_emad_alloc drivers/net/ethernet/mellanox/mlxsw/core.c:756 [inline]
mlxsw_emad_reg_access drivers/net/ethernet/mellanox/mlxsw/core.c:787 [inline]
mlxsw_core_reg_access_emad+0x1ab/0x1420 drivers/net/ethernet/mellanox/mlxsw/core.c:1817
mlxsw_reg_trans_query+0x39/0x50 drivers/net/ethernet/mellanox/mlxsw/core.c:1831
mlxsw_sp_sb_pm_occ_clear drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c:260 [inline]
mlxsw_sp_sb_occ_max_clear+0xbff/0x10a0 drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c:1365
mlxsw_devlink_sb_occ_max_clear+0x76/0xb0 drivers/net/ethernet/mellanox/mlxsw/core.c:1037
devlink_nl_cmd_sb_occ_max_clear_doit+0x1ec/0x280 net/core/devlink.c:1765
genl_family_rcv_msg_doit net/netlink/genetlink.c:669 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:714 [inline]
genl_rcv_msg+0x617/0x980 net/netlink/genetlink.c:731
netlink_rcv_skb+0x152/0x440 net/netlink/af_netlink.c:2470
genl_rcv+0x24/0x40 net/netlink/genetlink.c:742
netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
netlink_unicast+0x53a/0x750 net/netlink/af_netlink.c:1330
netlink_sendmsg+0x850/0xd90 net/netlink/af_netlink.c:1919
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0x150/0x190 net/socket.c:671
____sys_sendmsg+0x6d8/0x840 net/socket.c:2359
___sys_sendmsg+0xff/0x170 net/socket.c:2413
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2446
do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:384
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Freed by task 73:
save_stack+0x1b/0x40 mm/kasan/common.c:48
set_track mm/kasan/common.c:56 [inline]
kasan_set_free_info mm/kasan/common.c:316 [inline]
__kasan_slab_free+0x12c/0x170 mm/kasan/common.c:455
slab_free_hook mm/slub.c:1474 [inline]
slab_free_freelist_hook mm/slub.c:1507 [inline]
slab_free mm/slub.c:3072 [inline]
kmem_cache_free+0xbe/0x380 mm/slub.c:3088
kfree_skbmem net/core/skbuff.c:622 [inline]
kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:616
__kfree_skb net/core/skbuff.c:679 [inline]
consume_skb net/core/skbuff.c:837 [inline]
consume_skb+0xe1/0x370 net/core/skbuff.c:831
mlxsw_emad_trans_finish+0x64/0x1c0 drivers/net/ethernet/mellanox/mlxsw/core.c:592
mlxsw_emad_transmit_retry.isra.0+0x9d/0xc0 drivers/net/ethernet/mellanox/mlxsw/core.c:613
mlxsw_emad_trans_timeout_work+0x43/0x50 drivers/net/ethernet/mellanox/mlxsw/core.c:625
process_one_work+0xa3e/0x17a0 kernel/workqueue.c:2269
worker_thread+0x9e/0x1050 kernel/workqueue.c:2415
kthread+0x355/0x470 kernel/kthread.c:291
ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:293
The buggy address belongs to the object at ffff88804f5703c0
which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 212 bytes inside of
224-byte region [ffff88804f5703c0, ffff88804f5704a0)
The buggy address belongs to the page:
page:ffffea00013d5c00 refcount:1 mapcount:0 mapping:0000000000000000
index:0x0
flags: 0x100000000000200(slab)
raw: 0100000000000200 dead000000000100 dead000000000122 ffff88806c625400
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88804f570380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff88804f570400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804f570480: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88804f570500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88804f570580: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
Fixes: caf7297e7ab5f ("mlxsw: core: Introduce support for asynchronous EMAD register access")
Signed-off-by: Amit Cohen <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Signed-off-by: Ido Schimmel <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
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Free the devlink instance during the teardown sequence in the non-reload
case to avoid the following memory leak.
unreferenced object 0xffff888232895000 (size 2048):
comm "modprobe", pid 1073, jiffies 4295568857 (age 164.871s)
hex dump (first 32 bytes):
00 01 00 00 00 00 ad de 22 01 00 00 00 00 ad de ........".......
10 50 89 32 82 88 ff ff 10 50 89 32 82 88 ff ff .P.2.....P.2....
backtrace:
[<00000000c704e9a6>] __kmalloc+0x13a/0x2a0
[<00000000ee30129d>] devlink_alloc+0xff/0x760
[<0000000092ab3e5d>] 0xffffffffa042e5b0
[<000000004f3f8a31>] 0xffffffffa042f6ad
[<0000000092800b4b>] 0xffffffffa0491df3
[<00000000c4843903>] local_pci_probe+0xcb/0x170
[<000000006993ded7>] pci_device_probe+0x2c2/0x4e0
[<00000000a8e0de75>] really_probe+0x2c5/0xf90
[<00000000d42ba75d>] driver_probe_device+0x1eb/0x340
[<00000000bcc95e05>] device_driver_attach+0x294/0x300
[<000000000e2bc177>] __driver_attach+0x167/0x2f0
[<000000007d44cd6e>] bus_for_each_dev+0x148/0x1f0
[<000000003cd5a91e>] driver_attach+0x45/0x60
[<000000000041ce51>] bus_add_driver+0x3b8/0x720
[<00000000f5215476>] driver_register+0x230/0x4e0
[<00000000d79356f5>] __pci_register_driver+0x190/0x200
Fixes: a22712a96291 ("mlxsw: core: Fix devlink unregister flow")
Signed-off-by: Ido Schimmel <[email protected]>
Reported-by: Vadim Pasternak <[email protected]>
Tested-by: Oleksandr Shamray <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
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During port creation the driver instructs the device to advertise all
the supported link modes queried from the device.
Since cited commit not all the link modes supported by the device are
supported by the driver. This can result in the device negotiating a
link mode that is not recognized by the driver causing ethtool to show
an unsupported speed:
$ ethtool swp1
...
Speed: Unknown!
This is especially problematic when the netdev is enslaved to a bond, as
the bond driver uses unknown speed as an indication that the link is
down:
[13048.900895] net_ratelimit: 86 callbacks suppressed
[13048.900902] t_bond0: (slave swp52): failed to get link speed/duplex
[13048.912160] t_bond0: (slave swp49): failed to get link speed/duplex
Fix this by making sure that only link modes that are supported by both
the device and the driver are advertised.
Fixes: b97cd891268d ("mlxsw: Remove 56G speed support")
Signed-off-by: Amit Cohen <[email protected]>
Signed-off-by: Ido Schimmel <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
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Since commit 12d16b397ce0 ("gpio: mxc: Support module build") the
CONFIG_GPIO_MXC option needs to be explicitly selected.
Select it to avoid boot issues on imx25/imx27 due to the lack of the
GPIO driver.
Signed-off-by: Fabio Estevam <[email protected]>
Signed-off-by: Shawn Guo <[email protected]>
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Since commit 12d16b397ce0 ("gpio: mxc: Support module build") the
CONFIG_GPIO_MXC option needs to be explicitly selected.
Select it to avoid boot issues on imx25/imx27 due to the lack of the
GPIO driver.
Signed-off-by: Fabio Estevam <[email protected]>
Signed-off-by: Shawn Guo <[email protected]>
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Karsten Graul says:
====================
net/smc: fixes 2020-10-23
Patch 1 fixes a potential null pointer dereference. Patch 2 takes care
of a suppressed return code and patch 3 corrects the system EID in the
ISM driver.
====================
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
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The system EID that is defined by the ISM driver is not correct. Using
an incorrect system EID allows to communicate with remote Linux systems
that use the same incorrect system EID, but when it comes to
interoperability with other operating systems then the system EIDs do
never match which prevents SMC-Dv2 communication.
Using the correct system EID fixes this problem.
Fixes: 201091ebb2a1 ("net/smc: introduce System Enterprise ID (SEID)")
Signed-off-by: Karsten Graul <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
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The patch that repaired the invalid return code in smcd_new_buf_create()
missed to take care of errno ENOSPC which has a special meaning that no
more DMBEs can be registered on the device. Fix that by keeping this
errno value during the translation of the return code.
Fixes: 6b1bbf94ab36 ("net/smc: fix invalid return code in smcd_new_buf_create()")
Signed-off-by: Karsten Graul <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
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smc_listen_work() calls smc_listen_decline() on label out_decl,
providing the ini pointer variable. But this pointer can still be null
when the label out_decl is reached.
Fix this by checking the ini variable in smc_listen_work() and call
smc_listen_decline() with the result directly.
Fixes: a7c9c5f4af7f ("net/smc: CLC accept / confirm V2")
Signed-off-by: Karsten Graul <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>
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During __vsock_create() CAP_NET_ADMIN is used to determine if the
vsock_sock->trusted should be set to true. This value is used later
for determing if a remote connection should be allowed to connect
to a restricted VM. Unfortunately, if the caller doesn't have
CAP_NET_ADMIN, an audit message such as an selinux denial is
generated even if the caller does not want a trusted socket.
Logging errors on success is confusing. To avoid this, switch the
capable(CAP_NET_ADMIN) check to the noaudit version.
Reported-by: Roman Kiryanov <[email protected]>
https://android-review.googlesource.com/c/device/generic/goldfish/+/1468545/
Signed-off-by: Jeff Vander Stoep <[email protected]>
Reviewed-by: James Morris <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
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The current code sets up the filter action field before
rewrites are set up. When the action 'switch' is used
with rewrites, this may result in initial few packets
that get switched out don't have rewrites applied
on them.
So, make sure filter action is set up along with rewrites
or only after everything else is set up for rewrites.
Fixes: 12b276fbf6e0 ("cxgb4: add support to create hash filters")
Signed-off-by: Raju Rangoju <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
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Smatch complains that "ret" might be uninitialized if we don't enter
the loop. We do always enter the loop so it's a false positive, but
it's cleaner to just return a literal zero and that silences the
warning as well.
Signed-off-by: Dan Carpenter <[email protected]>
Link: https://lore.kernel.org/r/20201023112212.GA282278@mwanda
Signed-off-by: Jakub Kicinski <[email protected]>
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The code to try to shut up sparse warnings about questionable locking
didn't shut up sparse: it made the result not parse as valid C at all,
since the end result now has a label with no statement.
The proper fix is to just always lock the hardware, the same way Bart
did in commit 8ae178760b23 ("scsi: qla2xxx: Simplify the functions for
dumping firmware"). That avoids the whole problem with having locking
that is not statically obvious.
But in the meantime, just remove the incorrect attempt at trying to
avoid a sparse warning that just made things worse.
This was exposed by commit 3e6efab865ac ("scsi: qla2xxx: Fix reset of
MPI firmware"), very similarly to how commit cbb01c2f2f63 ("scsi:
qla2xxx: Fix MPI failure AEN (8200) handling") exposed the same problem
in another place, and caused that commit 8ae178760b23.
Please don't add code to just shut up sparse without actually fixing
what sparse complains about.
Reported-by: Luc Van Oostenryck <[email protected]>
Cc: Bart Van Assche <[email protected]>
Cc: Arun Easi <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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A couple of um files ended up not including the header file that defines
the __section() macro, and the simplest fix is to just revert the change
for those files.
Fixes: 33def8498fdd treewide: Convert macro and uses of __section(foo) to __section("foo")
Reported-and-tested-by: Guenter Roeck <[email protected]>
Cc: Joe Perches <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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Some drivers (such as EFA) have a GID table, but aren't IB/RoCE devices.
Remove the unnecessary rdma_ib_or_roce() check.
This fixes rdma-core failures for EFA when it uses the new ioctl interface
for querying the GID table.
Fixes: 9f85cbe50aa0 ("RDMA/uverbs: Expose the new GID query API to user space")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Gal Pressman <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
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When a mlx5 core devlink instance is reloaded in different net namespace,
its associated IB device is deleted and recreated.
Example sequence is:
$ ip netns add foo
$ devlink dev reload pci/0000:00:08.0 netns foo
$ ip netns del foo
mlx5 IB device needs to attach and detach the netdevice to it through the
netdev notifier chain during load and unload sequence. A below call graph
of the unload flow.
cleanup_net()
down_read(&pernet_ops_rwsem); <- first sem acquired
ops_pre_exit_list()
pre_exit()
devlink_pernet_pre_exit()
devlink_reload()
mlx5_devlink_reload_down()
mlx5_unload_one()
[...]
mlx5_ib_remove()
mlx5_ib_unbind_slave_port()
mlx5_remove_netdev_notifier()
unregister_netdevice_notifier()
down_write(&pernet_ops_rwsem);<- recurrsive lock
Hence, when net namespace is deleted, mlx5 reload results in deadlock.
When deadlock occurs, devlink mutex is also held. This not only deadlocks
the mlx5 device under reload, but all the processes which attempt to
access unrelated devlink devices are deadlocked.
Hence, fix this by mlx5 ib driver to register for per net netdev notifier
instead of global one, which operats on the net namespace without holding
the pernet_ops_rwsem.
Fixes: 4383cfcc65e7 ("net/mlx5: Add devlink reload")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Parav Pandit <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
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The patch referenced below has a typo that results in using the wrong L2
header size for outbound traffic. (V4 <-> V6).
It also breaks kernel-side RC traffic because they use AVs that use
RDMA_NETWORK_XXX enums instead of RXE_NETWORK_TYPE_XXX enums. Fix this by
transcoding between these enum types.
Fixes: e0d696d201dd ("RDMA/rxe: Move the definitions for rxe_av.network_type to uAPI")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bob Pearson <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
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In commit 8d98416a55eb ("scsi: hisi_sas: Switch v3 hw to MQ"), the dispatch
function was changed to choose the delivery queue based on the request tag
HW queue index.
This heavily degrades performance for v2 hw, since the HW queues are not
exposed there, and, as such, HW queue #0 is used for every command.
Revert to previous behaviour for when nr_hw_queues is not set, that being
to choose the HW queue based on target device index.
Link: https://lore.kernel.org/r/[email protected]
Fixes: 8d98416a55eb ("scsi: hisi_sas: Switch v3 hw to MQ")
Signed-off-by: John Garry <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
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This patch simplifies the ASSERT*() and BREAK_TO_DEBUGGER() macros:
- Move the dependency check of CONFIG_KGDB into Kconfig
- Unify the kgdb_breakpoint() call
- Drop the non-existing CONFIG_HAVE_KGDB
Also align the behavior of ASSERT() macro in both cases with and
without CONFIG_DEBUG_KERNEL_DC.
Acked-by: Alex Deucher <[email protected]>
Reviewed-by: Nicholas Kazlauskas <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
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ASSERT_CRITICAL() invokes kgdb_breakpoint() whenever either
CONFIG_KGDB or CONFIG_HAVE_KGDB is set. This, however, may lead to a
kernel panic when no kdb stuff is attached, since the
kgdb_breakpoint() call issues INT3. It's nothing but a surprise for
normal end-users.
For avoiding the pitfall, make the kgdb_breakpoint() call only when
CONFIG_DEBUG_KERNEL_DC is set.
https://bugzilla.opensuse.org/show_bug.cgi?id=1177973
Cc: <[email protected]>
Acked-by: Alex Deucher <[email protected]>
Reviewed-by: Nicholas Kazlauskas <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
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Currently both error code paths handled in dal_gpio_open_ex() issues
ASSERT_CRITICAL(), and this leads to a kernel panic unnecessarily if
CONFIG_KGDB is enabled. Since basically both are non-critical errors
and can be recovered, drop those assert calls and use a safer one,
BREAK_TO_DEBUGGER(), for allowing the debugging, instead.
BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1177973
Cc: <[email protected]>
Acked-by: Alex Deucher <[email protected]>
Reviewed-by: Nicholas Kazlauskas <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
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It looks this was accidently lost in a follow up patch.
dc context is large and we don't need contiguous pages.
Fixes: e4863f118a7d ("drm/amd/display: Multi display cause system lag on mode change")
Reviewed-by: Nicholas Kazlauskas <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Cc: Aric Cyr <[email protected]>
Cc: Alex Xu <[email protected]>
Reported-by: Alex Xu (Hello71) <[email protected]>
Tested-by: Alex Xu (Hello71) <[email protected]>
Cc: [email protected]
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why:
oem-related ddc read/write fails without these regs
how:
copy from hw_factory_dcn20.c
Signed-off-by: Martin Leung <[email protected]>
Acked-by: Aurabindo Pillai <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
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After a loss of transport due to an adapter migration or crash/disconnect
from the host partner there is a tiny window where we can race adjusting
the request_limit of the adapter. The request limit is atomically
increased/decreased to track the number of inflight requests against the
allowed limit of our VIOS partner.
After a transport loss we set the request_limit to zero to reflect this
state. However, there is a window where the adapter may attempt to queue a
command because the transport loss event hasn't been fully processed yet
and request_limit is still greater than zero. The hypercall to send the
event will fail and the error path will increment the request_limit as a
result. If the adapter processes the transport event prior to this
increment the request_limit becomes out of sync with the adapter state and
can result in SCSI commands being submitted on the now reset connection
prior to an SRP Login resulting in a protocol violation.
Fix this race by protecting request_limit with the host lock when changing
the value via atomic_set() to indicate no transport.
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Tyrel Datwyler <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
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'additionalProperties/unevalutatedProperties'
Another round of wack-a-mole. The json-schema default is additional
unknown properties are allowed, but for DT all properties should be
defined.
Signed-off-by: Rob Herring <[email protected]>
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In order to add meta-schema checks for additional/unevaluatedProperties
being present, all schema need to make this explicit. As the top-level
board/SoC schemas always have additional properties, add
'additionalProperties: true'.
Acked-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Viresh Kumar <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Rob Herring <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>
|
|
Clean-up incorrect indentation, extra spaces, and missing EOF newline in
schema files. Most of the clean-ups are for list indentation which
should always be 2 spaces more than the preceding keyword.
Found with yamllint (now integrated into the checks).
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Acked-by: Wolfram Sang <[email protected]> # for I2C
Acked-by: Sam Ravnborg <[email protected]> # for display
Acked-by: Jonathan Cameron <[email protected]> #for-iio
Signed-off-by: Rob Herring <[email protected]>
|
|
Add missing properties that are currently used in the examples of
subnode bindings and in many DTs.
Also updates the example in sound/google,cros-ec-codec.yaml to comply
with the google,cros-ec binding.
Reviewed-by: Enric Balletbo i Serra <[email protected]>
Signed-off-by: Ricardo Cañuelo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[robh: Add missing '#address-cells' and '#size-cells']
Signed-off-by: Rob Herring <[email protected]>
|
|
Convert the google,cros-ec-keyb binding to YAML and add it as a property
of google,cros-ec.yaml
Reviewed-by: Enric Balletbo i Serra <[email protected]>
Signed-off-by: Ricardo Cañuelo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>
|
|
Convert the google,cros-ec-i2c-tunnel binding to YAML and add it as a
property of google,cros-ec.yaml.
Reviewed-by: Enric Balletbo i Serra <[email protected]>
Signed-off-by: Ricardo Cañuelo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[robh: add ref to i2c-controller.yaml]
Signed-off-by: Rob Herring <[email protected]>
|
|
Prevent null pointer access when checking odm tree.
Signed-off-by: Dmytro Laktyushkin <[email protected]>
Acked-by: Aurabindo Pillai <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Cc: <[email protected]>
|
|
Ideally this should be a multiple of the VM block size.
2MB should at least fit for Vega/Navi.
Signed-off-by: Christian König <[email protected]>
Reviewed-by: Madhav Chauhan <[email protected]>
Reviewed-by: Felix Kuehling <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Cc: [email protected]
|
|
[why]
get_pixel_clk_frequency_100hz is undefined in clock_source_funcs.
[how]
set function pointer: ".get_pixel_clk_frequency_100hz = get_pixel_clk_frequency_100hz"
Signed-off-by: David Galiffi <[email protected]>
Reviewed-by: Bhawanpreet Lakha <[email protected]>
Acked-by: Aurabindo Pillai <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
|
|
2MB area is reserved at top inside VM.
Suggested-by: Christian König <[email protected]>
Signed-off-by: Madhav Chauhan <[email protected]>
Reviewed-by: Christian König <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Cc: [email protected]
|
|
Reviewed-by: Alex Deucher <[email protected]>
Reviewed-by: Guchun Chen <[email protected]>
Signed-off-by: Tianci.Yin <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
|
|
The blockchain SKU has no display and video support, remove them.
Reviewed-by: Alex Deucher <[email protected]>
Signed-off-by: Tianci.Yin <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
|
|
The mptscsih_remove() function triggers a kernel oops if the Scsi_Host
pointer (ioc->sh) is NULL, as can be seen in this syslog:
ioc0: LSI53C1030 B2: Capabilities={Initiator,Target}
Begin: Waiting for root file system ...
scsi host2: error handler thread failed to spawn, error = -4
mptspi: ioc0: WARNING - Unable to register controller with SCSI subsystem
Backtrace:
[<000000001045b7cc>] mptspi_probe+0x248/0x3d0 [mptspi]
[<0000000040946470>] pci_device_probe+0x1ac/0x2d8
[<0000000040add668>] really_probe+0x1bc/0x988
[<0000000040ade704>] driver_probe_device+0x160/0x218
[<0000000040adee24>] device_driver_attach+0x160/0x188
[<0000000040adef90>] __driver_attach+0x144/0x320
[<0000000040ad7c78>] bus_for_each_dev+0xd4/0x158
[<0000000040adc138>] driver_attach+0x4c/0x80
[<0000000040adb3ec>] bus_add_driver+0x3e0/0x498
[<0000000040ae0130>] driver_register+0xf4/0x298
[<00000000409450c4>] __pci_register_driver+0x78/0xa8
[<000000000007d248>] mptspi_init+0x18c/0x1c4 [mptspi]
This patch adds the necessary NULL-pointer checks. Successfully tested on
a HP C8000 parisc workstation with buggy SCSI drives.
Link: https://lore.kernel.org/r/[email protected]
Cc: <[email protected]>
Signed-off-by: Helge Deller <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
|
|
When the fcport is about to be deleted we should return EBUSY instead of
ENODEV. Only for EBUSY will the request be requeued in a multipath setup.
Also return EBUSY when the firmware has not yet started to avoid dropping
the request.
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Arun Easi <[email protected]>
Signed-off-by: Daniel Wagner <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
|
|
The current scanning mechanism is supposed to fall back to a synchronous
host scan if an asynchronous scan is in progress. However, this rule isn't
strictly respected, scsi_prep_async_scan() doesn't hold scan_mutex when
checking shost->async_scan. When scsi_scan_host() is called concurrently,
two async scans on same host can be started and a hang in do_scan_async()
is observed.
Fixes this issue by checking & setting shost->async_scan atomically with
shost->scan_mutex.
Link: https://lore.kernel.org/r/[email protected]
Cc: Christoph Hellwig <[email protected]>
Cc: Ewan D. Milne <[email protected]>
Cc: Hannes Reinecke <[email protected]>
Cc: Bart Van Assche <[email protected]>
Reviewed-by: Lee Duncan <[email protected]>
Reviewed-by: Bart Van Assche <[email protected]>
Signed-off-by: Ming Lei <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
|
|
Cover also the include/dt-bindings/memory/ headers in the memory
controller drivers entry.
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:
"This fixes a regression in x86/poly1305"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: x86/poly1305 - add back a needed assignment
|
|
If ->readpage returns an error, it has already unlocked the page.
Fixes: 5e929b33c393 ("CacheFiles: Handle truncate unlocking the page we're reading")
Cc: [email protected]
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: David Howells <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fix from Heiko Carstens:
"Fix s390 compile breakage caused by commit 33def8498fdd ("treewide:
Convert macro and uses of __section(foo) to __section("foo")")"
* tag 's390-5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: correct __bootdata / __bootdata_preserved macros
|
|
git://git.linaro.org:/people/jens.wiklander/linux-tee into arm/drivers
Use UUID API to export the UUID
Uses export_uuid() to export and uuid_t to an u8 array instead of depending
on the internals of uuid_t.
* tag 'optee-use-uuid-api-for-v5.10' of git://git.linaro.org:/people/jens.wiklander/linux-tee:
tee: optee: Use UUID API for exporting the UUID
Link: https://lore.kernel.org/r/20201013063612.GA3325842@jade
Signed-off-by: Arnd Bergmann <[email protected]>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into arm/fixes
i.MX fixes for 5.10:
With commit 12d16b397ce0 ("gpio: mxc: Support module build") in place,
GPIO_MXC has no 'def_bool y' anymore, and needs to be enabled by
defconfig. It updates the defconfig files to explicitly enable the
option for fixing boot failure on i.MX platform.
* tag 'imx-fixes-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
ARM: multi_v7_defconfig: Build in CONFIG_GPIO_MXC by default
ARM: imx_v6_v7_defconfig: Build in CONFIG_GPIO_MXC by default
arm64: defconfig: Build in CONFIG_GPIO_MXC by default
Link: https://lore.kernel.org/r/20201026135601.GA32675@dragon
Signed-off-by: Arnd Bergmann <[email protected]>
|
|
I got the following lockdep splat with tree locks converted to rwsem
patches on btrfs/104:
======================================================
WARNING: possible circular locking dependency detected
5.9.0+ #102 Not tainted
------------------------------------------------------
btrfs-cleaner/903 is trying to acquire lock:
ffff8e7fab6ffe30 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x32/0x170
but task is already holding lock:
ffff8e7fab628a88 (&fs_info->commit_root_sem){++++}-{3:3}, at: btrfs_find_all_roots+0x41/0x80
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&fs_info->commit_root_sem){++++}-{3:3}:
down_read+0x40/0x130
caching_thread+0x53/0x5a0
btrfs_work_helper+0xfa/0x520
process_one_work+0x238/0x540
worker_thread+0x55/0x3c0
kthread+0x13a/0x150
ret_from_fork+0x1f/0x30
-> #2 (&caching_ctl->mutex){+.+.}-{3:3}:
__mutex_lock+0x7e/0x7b0
btrfs_cache_block_group+0x1e0/0x510
find_free_extent+0xb6e/0x12f0
btrfs_reserve_extent+0xb3/0x1b0
btrfs_alloc_tree_block+0xb1/0x330
alloc_tree_block_no_bg_flush+0x4f/0x60
__btrfs_cow_block+0x11d/0x580
btrfs_cow_block+0x10c/0x220
commit_cowonly_roots+0x47/0x2e0
btrfs_commit_transaction+0x595/0xbd0
sync_filesystem+0x74/0x90
generic_shutdown_super+0x22/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20
deactivate_locked_super+0x36/0xa0
cleanup_mnt+0x12d/0x190
task_work_run+0x5c/0xa0
exit_to_user_mode_prepare+0x1df/0x200
syscall_exit_to_user_mode+0x54/0x280
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #1 (&space_info->groups_sem){++++}-{3:3}:
down_read+0x40/0x130
find_free_extent+0x2ed/0x12f0
btrfs_reserve_extent+0xb3/0x1b0
btrfs_alloc_tree_block+0xb1/0x330
alloc_tree_block_no_bg_flush+0x4f/0x60
__btrfs_cow_block+0x11d/0x580
btrfs_cow_block+0x10c/0x220
commit_cowonly_roots+0x47/0x2e0
btrfs_commit_transaction+0x595/0xbd0
sync_filesystem+0x74/0x90
generic_shutdown_super+0x22/0x100
kill_anon_super+0x14/0x30
btrfs_kill_super+0x12/0x20
deactivate_locked_super+0x36/0xa0
cleanup_mnt+0x12d/0x190
task_work_run+0x5c/0xa0
exit_to_user_mode_prepare+0x1df/0x200
syscall_exit_to_user_mode+0x54/0x280
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (btrfs-root-00){++++}-{3:3}:
__lock_acquire+0x1167/0x2150
lock_acquire+0xb9/0x3d0
down_read_nested+0x43/0x130
__btrfs_tree_read_lock+0x32/0x170
__btrfs_read_lock_root_node+0x3a/0x50
btrfs_search_slot+0x614/0x9d0
btrfs_find_root+0x35/0x1b0
btrfs_read_tree_root+0x61/0x120
btrfs_get_root_ref+0x14b/0x600
find_parent_nodes+0x3e6/0x1b30
btrfs_find_all_roots_safe+0xb4/0x130
btrfs_find_all_roots+0x60/0x80
btrfs_qgroup_trace_extent_post+0x27/0x40
btrfs_add_delayed_data_ref+0x3fd/0x460
btrfs_free_extent+0x42/0x100
__btrfs_mod_ref+0x1d7/0x2f0
walk_up_proc+0x11c/0x400
walk_up_tree+0xf0/0x180
btrfs_drop_snapshot+0x1c7/0x780
btrfs_clean_one_deleted_snapshot+0xfb/0x110
cleaner_kthread+0xd4/0x140
kthread+0x13a/0x150
ret_from_fork+0x1f/0x30
other info that might help us debug this:
Chain exists of:
btrfs-root-00 --> &caching_ctl->mutex --> &fs_info->commit_root_sem
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&fs_info->commit_root_sem);
lock(&caching_ctl->mutex);
lock(&fs_info->commit_root_sem);
lock(btrfs-root-00);
*** DEADLOCK ***
3 locks held by btrfs-cleaner/903:
#0: ffff8e7fab628838 (&fs_info->cleaner_mutex){+.+.}-{3:3}, at: cleaner_kthread+0x6e/0x140
#1: ffff8e7faadac640 (sb_internal){.+.+}-{0:0}, at: start_transaction+0x40b/0x5c0
#2: ffff8e7fab628a88 (&fs_info->commit_root_sem){++++}-{3:3}, at: btrfs_find_all_roots+0x41/0x80
stack backtrace:
CPU: 0 PID: 903 Comm: btrfs-cleaner Not tainted 5.9.0+ #102
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014
Call Trace:
dump_stack+0x8b/0xb0
check_noncircular+0xcf/0xf0
__lock_acquire+0x1167/0x2150
? __bfs+0x42/0x210
lock_acquire+0xb9/0x3d0
? __btrfs_tree_read_lock+0x32/0x170
down_read_nested+0x43/0x130
? __btrfs_tree_read_lock+0x32/0x170
__btrfs_tree_read_lock+0x32/0x170
__btrfs_read_lock_root_node+0x3a/0x50
btrfs_search_slot+0x614/0x9d0
? find_held_lock+0x2b/0x80
btrfs_find_root+0x35/0x1b0
? do_raw_spin_unlock+0x4b/0xa0
btrfs_read_tree_root+0x61/0x120
btrfs_get_root_ref+0x14b/0x600
find_parent_nodes+0x3e6/0x1b30
btrfs_find_all_roots_safe+0xb4/0x130
btrfs_find_all_roots+0x60/0x80
btrfs_qgroup_trace_extent_post+0x27/0x40
btrfs_add_delayed_data_ref+0x3fd/0x460
btrfs_free_extent+0x42/0x100
__btrfs_mod_ref+0x1d7/0x2f0
walk_up_proc+0x11c/0x400
walk_up_tree+0xf0/0x180
btrfs_drop_snapshot+0x1c7/0x780
? btrfs_clean_one_deleted_snapshot+0x73/0x110
btrfs_clean_one_deleted_snapshot+0xfb/0x110
cleaner_kthread+0xd4/0x140
? btrfs_alloc_root+0x50/0x50
kthread+0x13a/0x150
? kthread_create_worker_on_cpu+0x40/0x40
ret_from_fork+0x1f/0x30
BTRFS info (device sdb): disk space caching is enabled
BTRFS info (device sdb): has skinny extents
This happens because qgroups does a backref lookup when we create a
delayed ref. From here it may have to look up a root from an indirect
ref, which does a normal lookup on the tree_root, which takes the read
lock on the tree_root nodes.
To fix this we need to add a variant for looking up roots that searches
the commit root of the tree_root. Then when we do the backref search
using the commit root we are sure to not take any locks on the tree_root
nodes. This gets rid of the lockdep splat when running btrfs/104.
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Signed-off-by: David Sterba <[email protected]>
|
|
When enabling qgroups we walk the tree_root and then add a qgroup item
for every root that we have. This creates a lock dependency on the
tree_root and qgroup_root, which results in the following lockdep splat
(with tree locks using rwsem), eg. in tests btrfs/017 or btrfs/022:
======================================================
WARNING: possible circular locking dependency detected
5.9.0-default+ #1299 Not tainted
------------------------------------------------------
btrfs/24552 is trying to acquire lock:
ffff9142dfc5f630 (btrfs-quota-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
but task is already holding lock:
ffff9142dfc5d0b0 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (btrfs-root-00){++++}-{3:3}:
__lock_acquire+0x3fb/0x730
lock_acquire.part.0+0x6a/0x130
down_read_nested+0x46/0x130
__btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
__btrfs_read_lock_root_node+0x3a/0x50 [btrfs]
btrfs_search_slot_get_root+0x11d/0x290 [btrfs]
btrfs_search_slot+0xc3/0x9f0 [btrfs]
btrfs_insert_item+0x6e/0x140 [btrfs]
btrfs_create_tree+0x1cb/0x240 [btrfs]
btrfs_quota_enable+0xcd/0x790 [btrfs]
btrfs_ioctl_quota_ctl+0xc9/0xe0 [btrfs]
__x64_sys_ioctl+0x83/0xa0
do_syscall_64+0x2d/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (btrfs-quota-00){++++}-{3:3}:
check_prev_add+0x91/0xc30
validate_chain+0x491/0x750
__lock_acquire+0x3fb/0x730
lock_acquire.part.0+0x6a/0x130
down_read_nested+0x46/0x130
__btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
__btrfs_read_lock_root_node+0x3a/0x50 [btrfs]
btrfs_search_slot_get_root+0x11d/0x290 [btrfs]
btrfs_search_slot+0xc3/0x9f0 [btrfs]
btrfs_insert_empty_items+0x58/0xa0 [btrfs]
add_qgroup_item.part.0+0x72/0x210 [btrfs]
btrfs_quota_enable+0x3bb/0x790 [btrfs]
btrfs_ioctl_quota_ctl+0xc9/0xe0 [btrfs]
__x64_sys_ioctl+0x83/0xa0
do_syscall_64+0x2d/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xa9
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(btrfs-root-00);
lock(btrfs-quota-00);
lock(btrfs-root-00);
lock(btrfs-quota-00);
*** DEADLOCK ***
5 locks held by btrfs/24552:
#0: ffff9142df431478 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0xa0
#1: ffff9142f9b10cc0 (&fs_info->subvol_sem){++++}-{3:3}, at: btrfs_ioctl_quota_ctl+0x7b/0xe0 [btrfs]
#2: ffff9142f9b11a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_quota_enable+0x3b/0x790 [btrfs]
#3: ffff9142df431698 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x406/0x510 [btrfs]
#4: ffff9142dfc5d0b0 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
stack backtrace:
CPU: 1 PID: 24552 Comm: btrfs Not tainted 5.9.0-default+ #1299
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
Call Trace:
dump_stack+0x77/0x97
check_noncircular+0xf3/0x110
check_prev_add+0x91/0xc30
validate_chain+0x491/0x750
__lock_acquire+0x3fb/0x730
lock_acquire.part.0+0x6a/0x130
? __btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
? lock_acquire+0xc4/0x140
? __btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
down_read_nested+0x46/0x130
? __btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
__btrfs_tree_read_lock+0x35/0x1c0 [btrfs]
? btrfs_root_node+0xd9/0x200 [btrfs]
__btrfs_read_lock_root_node+0x3a/0x50 [btrfs]
btrfs_search_slot_get_root+0x11d/0x290 [btrfs]
btrfs_search_slot+0xc3/0x9f0 [btrfs]
btrfs_insert_empty_items+0x58/0xa0 [btrfs]
add_qgroup_item.part.0+0x72/0x210 [btrfs]
btrfs_quota_enable+0x3bb/0x790 [btrfs]
btrfs_ioctl_quota_ctl+0xc9/0xe0 [btrfs]
__x64_sys_ioctl+0x83/0xa0
do_syscall_64+0x2d/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix this by dropping the path whenever we find a root item, add the
qgroup item, and then re-lookup the root item we found and continue
processing roots.
Reported-by: David Sterba <[email protected]>
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
|
|
Very sporadically I had test case btrfs/069 from fstests hanging (for
years, it is not a recent regression), with the following traces in
dmesg/syslog:
[162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started
[162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0
[162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished
[162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds.
[162513.514318] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.514747] task:btrfs-transacti state:D stack: 0 pid:1356167 ppid: 2 flags:0x00004000
[162513.514751] Call Trace:
[162513.514761] __schedule+0x5ce/0xd00
[162513.514765] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.514771] schedule+0x46/0xf0
[162513.514844] wait_current_trans+0xde/0x140 [btrfs]
[162513.514850] ? finish_wait+0x90/0x90
[162513.514864] start_transaction+0x37c/0x5f0 [btrfs]
[162513.514879] transaction_kthread+0xa4/0x170 [btrfs]
[162513.514891] ? btrfs_cleanup_transaction+0x660/0x660 [btrfs]
[162513.514894] kthread+0x153/0x170
[162513.514897] ? kthread_stop+0x2c0/0x2c0
[162513.514902] ret_from_fork+0x22/0x30
[162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds.
[162513.515192] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.515680] task:fsstress state:D stack: 0 pid:1356184 ppid:1356177 flags:0x00004000
[162513.515682] Call Trace:
[162513.515688] __schedule+0x5ce/0xd00
[162513.515691] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.515697] schedule+0x46/0xf0
[162513.515712] wait_current_trans+0xde/0x140 [btrfs]
[162513.515716] ? finish_wait+0x90/0x90
[162513.515729] start_transaction+0x37c/0x5f0 [btrfs]
[162513.515743] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
[162513.515753] btrfs_sync_fs+0x61/0x1c0 [btrfs]
[162513.515758] ? __ia32_sys_fdatasync+0x20/0x20
[162513.515761] iterate_supers+0x87/0xf0
[162513.515765] ksys_sync+0x60/0xb0
[162513.515768] __do_sys_sync+0xa/0x10
[162513.515771] do_syscall_64+0x33/0x80
[162513.515774] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.515781] RIP: 0033:0x7f5238f50bd7
[162513.515782] Code: Bad RIP value.
[162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
[162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
[162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a
[162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0
[162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a
[162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
[162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds.
[162513.516064] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.516617] task:fsstress state:D stack: 0 pid:1356185 ppid:1356177 flags:0x00000000
[162513.516620] Call Trace:
[162513.516625] __schedule+0x5ce/0xd00
[162513.516628] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.516634] schedule+0x46/0xf0
[162513.516647] wait_current_trans+0xde/0x140 [btrfs]
[162513.516650] ? finish_wait+0x90/0x90
[162513.516662] start_transaction+0x4d7/0x5f0 [btrfs]
[162513.516679] btrfs_setxattr_trans+0x3c/0x100 [btrfs]
[162513.516686] __vfs_setxattr+0x66/0x80
[162513.516691] __vfs_setxattr_noperm+0x70/0x200
[162513.516697] vfs_setxattr+0x6b/0x120
[162513.516703] setxattr+0x125/0x240
[162513.516709] ? lock_acquire+0xb1/0x480
[162513.516712] ? mnt_want_write+0x20/0x50
[162513.516721] ? rcu_read_lock_any_held+0x8e/0xb0
[162513.516723] ? preempt_count_add+0x49/0xa0
[162513.516725] ? __sb_start_write+0x19b/0x290
[162513.516727] ? preempt_count_add+0x49/0xa0
[162513.516732] path_setxattr+0xba/0xd0
[162513.516739] __x64_sys_setxattr+0x27/0x30
[162513.516741] do_syscall_64+0x33/0x80
[162513.516743] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.516745] RIP: 0033:0x7f5238f56d5a
[162513.516746] Code: Bad RIP value.
[162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc
[162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a
[162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470
[162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700
[162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004
[162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0
[162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds.
[162513.517064] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.517763] task:fsstress state:D stack: 0 pid:1356196 ppid:1356177 flags:0x00004000
[162513.517780] Call Trace:
[162513.517786] __schedule+0x5ce/0xd00
[162513.517789] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.517796] schedule+0x46/0xf0
[162513.517810] wait_current_trans+0xde/0x140 [btrfs]
[162513.517814] ? finish_wait+0x90/0x90
[162513.517829] start_transaction+0x37c/0x5f0 [btrfs]
[162513.517845] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
[162513.517857] btrfs_sync_fs+0x61/0x1c0 [btrfs]
[162513.517862] ? __ia32_sys_fdatasync+0x20/0x20
[162513.517865] iterate_supers+0x87/0xf0
[162513.517869] ksys_sync+0x60/0xb0
[162513.517872] __do_sys_sync+0xa/0x10
[162513.517875] do_syscall_64+0x33/0x80
[162513.517878] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.517881] RIP: 0033:0x7f5238f50bd7
[162513.517883] Code: Bad RIP value.
[162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
[162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
[162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053
[162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0
[162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053
[162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
[162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds.
[162513.518298] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.519157] task:fsstress state:D stack: 0 pid:1356197 ppid:1356177 flags:0x00000000
[162513.519160] Call Trace:
[162513.519165] __schedule+0x5ce/0xd00
[162513.519168] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.519174] schedule+0x46/0xf0
[162513.519190] wait_current_trans+0xde/0x140 [btrfs]
[162513.519193] ? finish_wait+0x90/0x90
[162513.519206] start_transaction+0x4d7/0x5f0 [btrfs]
[162513.519222] btrfs_create+0x57/0x200 [btrfs]
[162513.519230] lookup_open+0x522/0x650
[162513.519246] path_openat+0x2b8/0xa50
[162513.519270] do_filp_open+0x91/0x100
[162513.519275] ? find_held_lock+0x32/0x90
[162513.519280] ? lock_acquired+0x33b/0x470
[162513.519285] ? do_raw_spin_unlock+0x4b/0xc0
[162513.519287] ? _raw_spin_unlock+0x29/0x40
[162513.519295] do_sys_openat2+0x20d/0x2d0
[162513.519300] do_sys_open+0x44/0x80
[162513.519304] do_syscall_64+0x33/0x80
[162513.519307] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.519309] RIP: 0033:0x7f5238f4a903
[162513.519310] Code: Bad RIP value.
[162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
[162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903
[162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470
[162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002
[162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013
[162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620
[162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds.
[162513.519727] Not tainted 5.9.0-rc6-btrfs-next-69 #1
[162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[162513.520508] task:btrfs state:D stack: 0 pid:1356211 ppid:1356178 flags:0x00004002
[162513.520511] Call Trace:
[162513.520516] __schedule+0x5ce/0xd00
[162513.520519] ? _raw_spin_unlock_irqrestore+0x3c/0x60
[162513.520525] schedule+0x46/0xf0
[162513.520544] btrfs_scrub_pause+0x11f/0x180 [btrfs]
[162513.520548] ? finish_wait+0x90/0x90
[162513.520562] btrfs_commit_transaction+0x45a/0xc30 [btrfs]
[162513.520574] ? start_transaction+0xe0/0x5f0 [btrfs]
[162513.520596] btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs]
[162513.520619] btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs]
[162513.520639] btrfs_ioctl+0x2a25/0x36f0 [btrfs]
[162513.520643] ? do_sigaction+0xf3/0x240
[162513.520645] ? find_held_lock+0x32/0x90
[162513.520648] ? do_sigaction+0xf3/0x240
[162513.520651] ? lock_acquired+0x33b/0x470
[162513.520655] ? _raw_spin_unlock_irq+0x24/0x50
[162513.520657] ? lockdep_hardirqs_on+0x7d/0x100
[162513.520660] ? _raw_spin_unlock_irq+0x35/0x50
[162513.520662] ? do_sigaction+0xf3/0x240
[162513.520671] ? __x64_sys_ioctl+0x83/0xb0
[162513.520672] __x64_sys_ioctl+0x83/0xb0
[162513.520677] do_syscall_64+0x33/0x80
[162513.520679] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[162513.520681] RIP: 0033:0x7fc3cd307d87
[162513.520682] Code: Bad RIP value.
[162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87
[162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003
[162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003
[162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001
[162513.520703]
Showing all locks held in the system:
[162513.520712] 1 lock held by khungtaskd/54:
[162513.520713] #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197
[162513.520728] 1 lock held by in:imklog/596:
[162513.520729] #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60
[162513.520782] 1 lock held by btrfs-transacti/1356167:
[162513.520784] #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs]
[162513.520798] 1 lock held by btrfs/1356190:
[162513.520800] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60
[162513.520805] 1 lock held by fsstress/1356184:
[162513.520806] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
[162513.520811] 3 locks held by fsstress/1356185:
[162513.520812] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
[162513.520815] #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120
[162513.520820] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
[162513.520833] 1 lock held by fsstress/1356196:
[162513.520834] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
[162513.520838] 3 locks held by fsstress/1356197:
[162513.520839] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
[162513.520843] #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50
[162513.520846] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
[162513.520858] 2 locks held by btrfs/1356211:
[162513.520859] #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs]
[162513.520877] #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
This was weird because the stack traces show that a transaction commit,
triggered by a device replace operation, is blocking trying to pause any
running scrubs but there are no stack traces of blocked tasks doing a
scrub.
After poking around with drgn, I noticed there was a scrub task that was
constantly running and blocking for shorts periods of time:
>>> t = find_task(prog, 1356190)
>>> prog.stack_trace(t)
#0 __schedule+0x5ce/0xcfc
#1 schedule+0x46/0xe4
#2 schedule_timeout+0x1df/0x475
#3 btrfs_reada_wait+0xda/0x132
#4 scrub_stripe+0x2a8/0x112f
#5 scrub_chunk+0xcd/0x134
#6 scrub_enumerate_chunks+0x29e/0x5ee
#7 btrfs_scrub_dev+0x2d5/0x91b
#8 btrfs_ioctl+0x7f5/0x36e7
#9 __x64_sys_ioctl+0x83/0xb0
#10 do_syscall_64+0x33/0x77
#11 entry_SYSCALL_64+0x7c/0x156
Which corresponds to:
int btrfs_reada_wait(void *handle)
{
struct reada_control *rc = handle;
struct btrfs_fs_info *fs_info = rc->fs_info;
while (atomic_read(&rc->elems)) {
if (!atomic_read(&fs_info->reada_works_cnt))
reada_start_machine(fs_info);
wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
(HZ + 9) / 10);
}
(...)
So the counter "rc->elems" was set to 1 and never decreased to 0, causing
the scrub task to loop forever in that function. Then I used the following
script for drgn to check the readahead requests:
$ cat dump_reada.py
import sys
import drgn
from drgn import NULL, Object, cast, container_of, execscript, \
reinterpret, sizeof
from drgn.helpers.linux import *
mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"
mnt = None
for mnt in for_each_mount(prog, dst = mnt_path):
pass
if mnt is None:
sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
sys.exit(1)
fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)
def dump_re(re):
nzones = re.nzones.value_()
print(f're at {hex(re.value_())}')
print(f'\t logical {re.logical.value_()}')
print(f'\t refcnt {re.refcnt.value_()}')
print(f'\t nzones {nzones}')
for i in range(nzones):
dev = re.zones[i].device
name = dev.name.str.string_()
print(f'\t\t dev id {dev.devid.value_()} name {name}')
print()
for _, e in radix_tree_for_each(fs_info.reada_tree):
re = cast('struct reada_extent *', e)
dump_re(re)
$ drgn dump_reada.py
re at 0xffff8f3da9d25ad8
logical 38928384
refcnt 1
nzones 1
dev id 0 name b'/dev/sdd'
$
So there was one readahead extent with a single zone corresponding to the
source device of that last device replace operation logged in dmesg/syslog.
Also the ID of that zone's device was 0 which is a special value set in
the source device of a device replace operation when the operation finishes
(constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()),
confirming again that device /dev/sdd was the source of a device replace
operation.
Normally there should be as many zones in the readahead extent as there are
devices, and I wasn't expecting the extent to be in a block group with a
'single' profile, so I went and confirmed with the following drgn script
that there weren't any single profile block groups:
$ cat dump_block_groups.py
import sys
import drgn
from drgn import NULL, Object, cast, container_of, execscript, \
reinterpret, sizeof
from drgn.helpers.linux import *
mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"
mnt = None
for mnt in for_each_mount(prog, dst = mnt_path):
pass
if mnt is None:
sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
sys.exit(1)
fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)
BTRFS_BLOCK_GROUP_DATA = (1 << 0)
BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1)
BTRFS_BLOCK_GROUP_METADATA = (1 << 2)
BTRFS_BLOCK_GROUP_RAID0 = (1 << 3)
BTRFS_BLOCK_GROUP_RAID1 = (1 << 4)
BTRFS_BLOCK_GROUP_DUP = (1 << 5)
BTRFS_BLOCK_GROUP_RAID10 = (1 << 6)
BTRFS_BLOCK_GROUP_RAID5 = (1 << 7)
BTRFS_BLOCK_GROUP_RAID6 = (1 << 8)
BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9)
BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10)
def bg_flags_string(bg):
flags = bg.flags.value_()
ret = ''
if flags & BTRFS_BLOCK_GROUP_DATA:
ret = 'data'
if flags & BTRFS_BLOCK_GROUP_METADATA:
if len(ret) > 0:
ret += '|'
ret += 'meta'
if flags & BTRFS_BLOCK_GROUP_SYSTEM:
if len(ret) > 0:
ret += '|'
ret += 'system'
if flags & BTRFS_BLOCK_GROUP_RAID0:
ret += ' raid0'
elif flags & BTRFS_BLOCK_GROUP_RAID1:
ret += ' raid1'
elif flags & BTRFS_BLOCK_GROUP_DUP:
ret += ' dup'
elif flags & BTRFS_BLOCK_GROUP_RAID10:
ret += ' raid10'
elif flags & BTRFS_BLOCK_GROUP_RAID5:
ret += ' raid5'
elif flags & BTRFS_BLOCK_GROUP_RAID6:
ret += ' raid6'
elif flags & BTRFS_BLOCK_GROUP_RAID1C3:
ret += ' raid1c3'
elif flags & BTRFS_BLOCK_GROUP_RAID1C4:
ret += ' raid1c4'
else:
ret += ' single'
return ret
def dump_bg(bg):
print()
print(f'block group at {hex(bg.value_())}')
print(f'\t start {bg.start.value_()} length {bg.length.value_()}')
print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}')
bg_root = fs_info.block_group_cache_tree.address_of_()
for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'):
dump_bg(bg)
$ drgn dump_block_groups.py
block group at 0xffff8f3d673b0400
start 22020096 length 16777216
flags 258 - system raid6
block group at 0xffff8f3d53ddb400
start 38797312 length 536870912
flags 260 - meta raid6
block group at 0xffff8f3d5f4d9c00
start 575668224 length 2147483648
flags 257 - data raid6
block group at 0xffff8f3d08189000
start 2723151872 length 67108864
flags 258 - system raid6
block group at 0xffff8f3db70ff000
start 2790260736 length 1073741824
flags 260 - meta raid6
block group at 0xffff8f3d5f4dd800
start 3864002560 length 67108864
flags 258 - system raid6
block group at 0xffff8f3d67037000
start 3931111424 length 2147483648
flags 257 - data raid6
$
So there were only 2 reasons left for having a readahead extent with a
single zone: reada_find_zone(), called when creating a readahead extent,
returned NULL either because we failed to find the corresponding block
group or because a memory allocation failed. With some additional and
custom tracing I figured out that on every further ocurrence of the
problem the block group had just been deleted when we were looping to
create the zones for the readahead extent (at reada_find_extent()), so we
ended up with only one zone in the readahead extent, corresponding to a
device that ends up getting replaced.
So after figuring that out it became obvious why the hang happens:
1) Task A starts a scrub on any device of the filesystem, except for
device /dev/sdd;
2) Task B starts a device replace with /dev/sdd as the source device;
3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently
starting to scrub a stripe from block group X. This call to
btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add()
calls reada_add_block(), it passes the logical address of the extent
tree's root node as its 'logical' argument - a value of 38928384;
4) Task A then enters reada_find_extent(), called from reada_add_block().
It finds there isn't any existing readahead extent for the logical
address 38928384, so it proceeds to the path of creating a new one.
It calls btrfs_map_block() to find out which stripes exist for the block
group X. On the first iteration of the for loop that iterates over the
stripes, it finds the stripe for device /dev/sdd, so it creates one
zone for that device and adds it to the readahead extent. Before getting
into the second iteration of the loop, the cleanup kthread deletes block
group X because it was empty. So in the iterations for the remaining
stripes it does not add more zones to the readahead extent, because the
calls to reada_find_zone() returned NULL because they couldn't find
block group X anymore.
As a result the new readahead extent has a single zone, corresponding to
the device /dev/sdd;
4) Before task A returns to btrfs_reada_add() and queues the readahead job
for the readahead work queue, task B finishes the device replace and at
btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new
device /dev/sdg;
5) Task A returns to reada_add_block(), which increments the counter
"->elems" of the reada_control structure allocated at btrfs_reada_add().
Then it returns back to btrfs_reada_add() and calls
reada_start_machine(). This queues a job in the readahead work queue to
run the function reada_start_machine_worker(), which calls
__reada_start_machine().
At __reada_start_machine() we take the device list mutex and for each
device found in the current device list, we call
reada_start_machine_dev() to start the readahead work. However at this
point the device /dev/sdd was already freed and is not in the device
list anymore.
This means the corresponding readahead for the extent at 38928384 is
never started, and therefore the "->elems" counter of the reada_control
structure allocated at btrfs_reada_add() never goes down to 0, causing
the call to btrfs_reada_wait(), done by the scrub task, to wait forever.
Note that the readahead request can be made either after the device replace
started or before it started, however in pratice it is very unlikely that a
device replace is able to start after a readahead request is made and is
able to complete before the readahead request completes - maybe only on a
very small and nearly empty filesystem.
This hang however is not the only problem we can have with readahead and
device removals. When the readahead extent has other zones other than the
one corresponding to the device that is being removed (either by a device
replace or a device remove operation), we risk having a use-after-free on
the device when dropping the last reference of the readahead extent.
For example if we create a readahead extent with two zones, one for the
device /dev/sdd and one for the device /dev/sde:
1) Before the readahead worker starts, the device /dev/sdd is removed,
and the corresponding btrfs_device structure is freed. However the
readahead extent still has the zone pointing to the device structure;
2) When the readahead worker starts, it only finds device /dev/sde in the
current device list of the filesystem;
3) It starts the readahead work, at reada_start_machine_dev(), using the
device /dev/sde;
4) Then when it finishes reading the extent from device /dev/sde, it calls
__readahead_hook() which ends up dropping the last reference on the
readahead extent through the last call to reada_extent_put();
5) At reada_extent_put() it iterates over each zone of the readahead extent
and attempts to delete an element from the device's 'reada_extents'
radix tree, resulting in a use-after-free, as the device pointer of the
zone for /dev/sdd is now stale. We can also access the device after
dropping the last reference of a zone, through reada_zone_release(),
also called by reada_extent_put().
And a device remove suffers the same problem, however since it shrinks the
device size down to zero before removing the device, it is very unlikely to
still have readahead requests not completed by the time we free the device,
the only possibility is if the device has a very little space allocated.
While the hang problem is exclusive to scrub, since it is currently the
only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free
problem affects any path that triggers readhead, which includes
btree_readahead_hook() and __readahead_hook() (a readahead worker can
trigger readahed for the children of a node) for example - any path that
ends up calling reada_add_block() can trigger the use-after-free after a
device is removed.
So fix this by waiting for any readahead requests for a device to complete
before removing a device, ensuring that while waiting for existing ones no
new ones can be made.
This problem has been around for a very long time - the readahead code was
added in 2011, device remove exists since 2008 and device replace was
introduced in 2013, hard to pick a specific commit for a git Fixes tag.
CC: [email protected] # 4.4+
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
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If we fail to find suitable zones for a new readahead extent, we end up
leaving a stale pointer in the global readahead extents radix tree
(fs_info->reada_tree), which can trigger the following trace later on:
[13367.696354] BUG: kernel NULL pointer dereference, address: 00000000000000b0
[13367.696802] #PF: supervisor read access in kernel mode
[13367.697249] #PF: error_code(0x0000) - not-present page
[13367.697721] PGD 0 P4D 0
[13367.698171] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
[13367.698632] CPU: 6 PID: 851214 Comm: btrfs Tainted: G W 5.9.0-rc6-btrfs-next-69 #1
[13367.699100] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[13367.700069] RIP: 0010:__lock_acquire+0x20a/0x3970
[13367.700562] Code: ff 1f 0f b7 c0 48 0f (...)
[13367.701609] RSP: 0018:ffffb14448f57790 EFLAGS: 00010046
[13367.702140] RAX: 0000000000000000 RBX: 29b935140c15e8cf RCX: 0000000000000000
[13367.702698] RDX: 0000000000000002 RSI: ffffffffb3d66bd0 RDI: 0000000000000046
[13367.703240] RBP: ffff8a52ba8ac040 R08: 00000c2866ad9288 R09: 0000000000000001
[13367.703783] R10: 0000000000000001 R11: 00000000b66d9b53 R12: ffff8a52ba8ac9b0
[13367.704330] R13: 0000000000000000 R14: ffff8a532b6333e8 R15: 0000000000000000
[13367.704880] FS: 00007fe1df6b5700(0000) GS:ffff8a5376600000(0000) knlGS:0000000000000000
[13367.705438] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[13367.705995] CR2: 00000000000000b0 CR3: 000000022cca8004 CR4: 00000000003706e0
[13367.706565] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[13367.707127] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[13367.707686] Call Trace:
[13367.708246] ? ___slab_alloc+0x395/0x740
[13367.708820] ? reada_add_block+0xae/0xee0 [btrfs]
[13367.709383] lock_acquire+0xb1/0x480
[13367.709955] ? reada_add_block+0xe0/0xee0 [btrfs]
[13367.710537] ? reada_add_block+0xae/0xee0 [btrfs]
[13367.711097] ? rcu_read_lock_sched_held+0x5d/0x90
[13367.711659] ? kmem_cache_alloc_trace+0x8d2/0x990
[13367.712221] ? lock_acquired+0x33b/0x470
[13367.712784] _raw_spin_lock+0x34/0x80
[13367.713356] ? reada_add_block+0xe0/0xee0 [btrfs]
[13367.713966] reada_add_block+0xe0/0xee0 [btrfs]
[13367.714529] ? btrfs_root_node+0x15/0x1f0 [btrfs]
[13367.715077] btrfs_reada_add+0x117/0x170 [btrfs]
[13367.715620] scrub_stripe+0x21e/0x10d0 [btrfs]
[13367.716141] ? kvm_sched_clock_read+0x5/0x10
[13367.716657] ? __lock_acquire+0x41e/0x3970
[13367.717184] ? scrub_chunk+0x60/0x140 [btrfs]
[13367.717697] ? find_held_lock+0x32/0x90
[13367.718254] ? scrub_chunk+0x60/0x140 [btrfs]
[13367.718773] ? lock_acquired+0x33b/0x470
[13367.719278] ? scrub_chunk+0xcd/0x140 [btrfs]
[13367.719786] scrub_chunk+0xcd/0x140 [btrfs]
[13367.720291] scrub_enumerate_chunks+0x270/0x5c0 [btrfs]
[13367.720787] ? finish_wait+0x90/0x90
[13367.721281] btrfs_scrub_dev+0x1ee/0x620 [btrfs]
[13367.721762] ? rcu_read_lock_any_held+0x8e/0xb0
[13367.722235] ? preempt_count_add+0x49/0xa0
[13367.722710] ? __sb_start_write+0x19b/0x290
[13367.723192] btrfs_ioctl+0x7f5/0x36f0 [btrfs]
[13367.723660] ? __fget_files+0x101/0x1d0
[13367.724118] ? find_held_lock+0x32/0x90
[13367.724559] ? __fget_files+0x101/0x1d0
[13367.724982] ? __x64_sys_ioctl+0x83/0xb0
[13367.725399] __x64_sys_ioctl+0x83/0xb0
[13367.725802] do_syscall_64+0x33/0x80
[13367.726188] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[13367.726574] RIP: 0033:0x7fe1df7add87
[13367.726948] Code: 00 00 00 48 8b 05 09 91 (...)
[13367.727763] RSP: 002b:00007fe1df6b4d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[13367.728179] RAX: ffffffffffffffda RBX: 000055ce1fb596a0 RCX: 00007fe1df7add87
[13367.728604] RDX: 000055ce1fb596a0 RSI: 00000000c400941b RDI: 0000000000000003
[13367.729021] RBP: 0000000000000000 R08: 00007fe1df6b5700 R09: 0000000000000000
[13367.729431] R10: 00007fe1df6b5700 R11: 0000000000000246 R12: 00007ffd922b07de
[13367.729842] R13: 00007ffd922b07df R14: 00007fe1df6b4e40 R15: 0000000000802000
[13367.730275] Modules linked in: btrfs blake2b_generic xor (...)
[13367.732638] CR2: 00000000000000b0
[13367.733166] ---[ end trace d298b6805556acd9 ]---
What happens is the following:
1) At reada_find_extent() we don't find any existing readahead extent for
the metadata extent starting at logical address X;
2) So we proceed to create a new one. We then call btrfs_map_block() to get
information about which stripes contain extent X;
3) After that we iterate over the stripes and create only one zone for the
readahead extent - only one because reada_find_zone() returned NULL for
all iterations except for one, either because a memory allocation failed
or it couldn't find the block group of the extent (it may have just been
deleted);
4) We then add the new readahead extent to the readahead extents radix
tree at fs_info->reada_tree;
5) Then we iterate over each zone of the new readahead extent, and find
that the device used for that zone no longer exists, because it was
removed or it was the source device of a device replace operation.
Since this left 'have_zone' set to 0, after finishing the loop we jump
to the 'error' label, call kfree() on the new readahead extent and
return without removing it from the radix tree at fs_info->reada_tree;
6) Any future call to reada_find_extent() for the logical address X will
find the stale pointer in the readahead extents radix tree, increment
its reference counter, which can trigger the use-after-free right
away or return it to the caller reada_add_block() that results in the
use-after-free of the example trace above.
So fix this by making sure we delete the readahead extent from the radix
tree if we fail to setup zones for it (when 'have_zone = 0').
Fixes: 319450211842ba ("btrfs: reada: bypass adding extent when all zone failed")
CC: [email protected] # 4.9+
Reviewed-by: Johannes Thumshirn <[email protected]>
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
|
|
If there's no parity and num_stripes < ncopies, a crafted image can
trigger a division by zero in calc_stripe_length().
The image was generated through fuzzing.
CC: [email protected] # 5.4+
Reviewed-by: Qu Wenruo <[email protected]>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209587
Signed-off-by: Daniel Xu <[email protected]>
Signed-off-by: David Sterba <[email protected]>
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