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We can currently call the timeout handler again on a request that has
already been handed over to the timeout handler. Prevent that with a new
flag.
Fixes: 12f5b931 ("blk-mq: Remove generation seqeunce")
Reported-by: Andrew Randrianasulu <randrianasulu@gmail.com>
Tested-by: Andrew Randrianasulu <randrianasulu@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is not allowed to reinit q->tag_set_list list entry while RCU grace
period has not completed yet, otherwise the following soft lockup in
blk_mq_sched_restart() happens:
[ 1064.252652] watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [fio:9270]
[ 1064.254445] task: ffff99b912e8b900 task.stack: ffffa6d54c758000
[ 1064.254613] RIP: 0010:blk_mq_sched_restart+0x96/0x150
[ 1064.256510] Call Trace:
[ 1064.256664] <IRQ>
[ 1064.256824] blk_mq_free_request+0xea/0x100
[ 1064.256987] msg_io_conf+0x59/0xd0 [ibnbd_client]
[ 1064.257175] complete_rdma_req+0xf2/0x230 [ibtrs_client]
[ 1064.257340] ? ibtrs_post_recv_empty+0x4d/0x70 [ibtrs_core]
[ 1064.257502] ibtrs_clt_rdma_done+0xd1/0x1e0 [ibtrs_client]
[ 1064.257669] ib_create_qp+0x321/0x380 [ib_core]
[ 1064.257841] ib_process_cq_direct+0xbd/0x120 [ib_core]
[ 1064.258007] irq_poll_softirq+0xb7/0xe0
[ 1064.258165] __do_softirq+0x106/0x2a2
[ 1064.258328] irq_exit+0x92/0xa0
[ 1064.258509] do_IRQ+0x4a/0xd0
[ 1064.258660] common_interrupt+0x7a/0x7a
[ 1064.258818] </IRQ>
Meanwhile another context frees other queue but with the same set of
shared tags:
[ 1288.201183] INFO: task bash:5910 blocked for more than 180 seconds.
[ 1288.201833] bash D 0 5910 5820 0x00000000
[ 1288.202016] Call Trace:
[ 1288.202315] schedule+0x32/0x80
[ 1288.202462] schedule_timeout+0x1e5/0x380
[ 1288.203838] wait_for_completion+0xb0/0x120
[ 1288.204137] __wait_rcu_gp+0x125/0x160
[ 1288.204287] synchronize_sched+0x6e/0x80
[ 1288.204770] blk_mq_free_queue+0x74/0xe0
[ 1288.204922] blk_cleanup_queue+0xc7/0x110
[ 1288.205073] ibnbd_clt_unmap_device+0x1bc/0x280 [ibnbd_client]
[ 1288.205389] ibnbd_clt_unmap_dev_store+0x169/0x1f0 [ibnbd_client]
[ 1288.205548] kernfs_fop_write+0x109/0x180
[ 1288.206328] vfs_write+0xb3/0x1a0
[ 1288.206476] SyS_write+0x52/0xc0
[ 1288.206624] do_syscall_64+0x68/0x1d0
[ 1288.206774] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
What happened is the following:
1. There are several MQ queues with shared tags.
2. One queue is about to be freed and now task is in
blk_mq_del_queue_tag_set().
3. Other CPU is in blk_mq_sched_restart() and loops over all queues in
tag list in order to find hctx to restart.
Because linked list entry was modified in blk_mq_del_queue_tag_set()
without proper waiting for a grace period, blk_mq_sched_restart()
never ends, spining in list_for_each_entry_rcu_rr(), thus soft lockup.
Fix is simple: reinit list entry after an RCU grace period elapsed.
Fixes: Fixes: 705cda97ee3a ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list")
Cc: stable@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-block@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull networking fixes from David Miller:
1) Fix several bpfilter/UMH bugs, in particular make the UMH build not
depend upon X86 specific Kconfig symbols. From Alexei Starovoitov.
2) Fix handling of modified context pointer in bpf verifier, from
Daniel Borkmann.
3) Kill regression in ifdown/ifup sequences for hv_netvsc driver, from
Dexuan Cui.
4) When the bonding primary member name changes, we have to re-evaluate
the bond->force_primary setting, from Xiangning Yu.
5) Eliminate possible padding beyone end of SKB in cdc_ncm driver, from
Bjørn Mork.
6) RX queue length reported for UDP sockets in procfs and socket diag
are inaccurate, from Paolo Abeni.
7) Fix br_fdb_find_port() locking, from Petr Machata.
8) Limit sk_rcvlowat values properly in TCP, from Soheil Hassas
Yeganeh.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (23 commits)
tcp: limit sk_rcvlowat by the maximum receive buffer
net: phy: dp83822: use BMCR_ANENABLE instead of BMSR_ANEGCAPABLE for DP83620
socket: close race condition between sock_close() and sockfs_setattr()
net: bridge: Fix locking in br_fdb_find_port()
udp: fix rx queue len reported by diag and proc interface
cdc_ncm: avoid padding beyond end of skb
net/sched: act_simple: fix parsing of TCA_DEF_DATA
net: fddi: fix a possible null-ptr-deref
net: aquantia: fix unsigned numvecs comparison with less than zero
net: stmmac: fix build failure due to missing COMMON_CLK dependency
bpfilter: fix race in pipe access
bpf, xdp: fix crash in xdp_umem_unaccount_pages
xsk: Fix umem fill/completion queue mmap on 32-bit
tools/bpf: fix selftest get_cgroup_id_user
bpfilter: fix OUTPUT_FORMAT
umh: fix race condition
net: mscc: ocelot: Fix uninitialized error in ocelot_netdevice_event()
bonding: re-evaluate force_primary when the primary slave name changes
ip_tunnel: Fix name string concatenate in __ip_tunnel_create()
hv_netvsc: Fix a network regression after ifdown/ifup
...
Pull RTC updates from Alexandre Belloni:
"Setting the supported range from drivers for RTCs failing soon has
started. A few fixes are developed along the way. Some drivers have
been switched to SPDX by their maintainers.
Subsystem:
- rework of the rtc-test driver which allows to test the core more
thoroughly
- rtc_set_alarm() now fails early when alarms are not supported
Drivers:
- mktime() is now replaced by mktime64()
- RTC range added for 88pm80x, ab-b5ze-s3, at91rm9200,
brcmstb-waketimer, ds1685, ftrtc010, ls1x, mxc_v2, rx8581, sprd,
st-lpc, tps6586x, tps65910 and vr41xx
- fixed a possible race condition in probe functions
- pxa: fix the probe function that is broken since v4.3
- stm32: now supports stm32mp1"
* tag 'rtc-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (78 commits)
rtc: pxa: fix probe function
rtc: cros-ec: Switch to SPDX identifier.
rtc: cros-ec: Make license text and module license match.
rtc: ensure rtc_set_alarm fails when alarms are not supported
rtc: test: remove alarm support from the first device
rtc: test: convert to devm_rtc_allocate_device
rtc: ftrtc010: let the core handle range
rtc: ftrtc010: handle dates after 2106
rtc: ftrtc010: switch to devm_rtc_allocate_device
rtc: mrst: switch to devm functions
rtc: sunxi: fix possible race condition
rtc: test: remove irq sysfs file
rtc: test: emulate alarms using timers
rtc: test: store time as an offset to system time
rtc: test: allow registering many devices
rtc: test: remove useless proc info
rtc: ds1685: Add range
rtc: ds1685: fix possible race condition
rtc: sprd: Add new RTC power down check method
rtc: sun6i: Fix bit_idx value for clk_register_gate
...
The user-provided value to setsockopt(SO_RCVLOWAT) can be
larger than the maximum possible receive buffer. Such values
mute POLLIN signals on the socket which can stall progress
on the socket.
Limit the user-provided value to half of the maximum receive
buffer, i.e., half of sk_rcvbuf when the receive buffer size
is set by the user, or otherwise half of sysctl_tcp_rmem[2].
Fixes: d1361840f8c5 ("tcp: fix SO_RCVLOWAT and RCVBUF autotuning")
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull UBI and UBIFS updates from Richard Weinberger:
- the UBI on-disk format header file is now dual licensed
- new way to detect Fastmap problems during runtime
- bugfix for Fastmap
- minor updates for UBIFS (spelling, comments, vm_fault_t, ...)
* tag 'upstream-4.18-rc1' of git://git.infradead.org/linux-ubifs:
mtd: ubi: Update ubi-media.h to dual license
ubi: fastmap: Detect EBA mismatches on-the-fly
ubi: fastmap: Check each mapping only once
ubi: fastmap: Correctly handle interrupted erasures in EBA
ubi: fastmap: Cancel work upon detach
ubifs: lpt: Fix wrong pnode number range in comment
ubifs: gc: Fix typo
ubifs: log: Some spelling fixes
ubifs: Spelling fix someting -> something
ubifs: journal: Remove wrong comment
ubifs: remove set but never used variable
ubifs, xattr: remove misguided quota flags
fs: ubifs: Adding new return type vm_fault_t
This patch is from static analysis and I don't have the hardware to
to test it. I think the test is reversed so now the probe function
will return success early and the last part of the function is dead
code.
Fixes: 3cdf4ad9633e ("rtc: pxa: convert to use shared sa1100 functions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
DP83620 register set is compatible with the DP83848, but it also supports
100base-FX. When the hardware is configured such as that fiber mode is
enabled, autonegotiation is not possible.
The chip, however, doesn't expose this information via BMSR_ANEGCAPABLE.
Instead, this bit is always set high, even if the particular hardware
configuration makes it so that auto negotiation is not possible [1]. Under
these circumstances, the phy subsystem keeps trying for autonegotiation to
happen, without success.
Hereby, we inspect BMCR_ANENABLE bit after genphy_config_init, which on
reset is set to 0 when auto negotiation is disabled, and so we use this
value instead of BMSR_ANEGCAPABLE.
[1] https://e2e.ti.com/support/interface/ethernet/f/903/p/697165/2571170
Signed-off-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull SCSI updates from James Bottomley:
"This is mostly updates to the usual drivers: ufs, qedf, mpt3sas, lpfc,
xfcp, hisi_sas, cxlflash, qla2xxx.
In the absence of Nic, we're also taking target updates which are
mostly minor except for the tcmu refactor.
The only real core change to worry about is the removal of high page
bouncing (in sas, storvsc and iscsi). This has been well tested and no
problems have shown up so far"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (268 commits)
scsi: lpfc: update driver version to 12.0.0.4
scsi: lpfc: Fix port initialization failure.
scsi: lpfc: Fix 16gb hbas failing cq create.
scsi: lpfc: Fix crash in blk_mq layer when executing modprobe -r lpfc
scsi: lpfc: correct oversubscription of nvme io requests for an adapter
scsi: lpfc: Fix MDS diagnostics failure (Rx < Tx)
scsi: hisi_sas: Mark PHY as in reset for nexus reset
scsi: hisi_sas: Fix return value when get_free_slot() failed
scsi: hisi_sas: Terminate STP reject quickly for v2 hw
scsi: hisi_sas: Add v2 hw force PHY function for internal ATA command
scsi: hisi_sas: Include TMF elements in struct hisi_sas_slot
scsi: hisi_sas: Try wait commands before before controller reset
scsi: hisi_sas: Init disks after controller reset
scsi: hisi_sas: Create a scsi_host_template per HW module
scsi: hisi_sas: Reset disks when discovered
scsi: hisi_sas: Add LED feature for v3 hw
scsi: hisi_sas: Change common allocation mode of device id
scsi: hisi_sas: change slot index allocation mode
scsi: hisi_sas: Introduce hisi_sas_phy_set_linkrate()
scsi: hisi_sas: fix a typo in hisi_sas_task_prep()
...
Update license template using SPDX. Move the global layout
of UBI headers to dual license helping UBI to be the standard
solution for raw NAND management.
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Artem Bityutskiy <dedekind1@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
fchownat() doesn't even hold refcnt of fd until it figures out
fd is really needed (otherwise is ignored) and releases it after
it resolves the path. This means sock_close() could race with
sockfs_setattr(), which leads to a NULL pointer dereference
since typically we set sock->sk to NULL in ->release().
As pointed out by Al, this is unique to sockfs. So we can fix this
in socket layer by acquiring inode_lock in sock_close() and
checking against NULL in sockfs_setattr().
sock_release() is called in many places, only the sock_close()
path matters here. And fortunately, this should not affect normal
sock_close() as it is only called when the last fd refcnt is gone.
It only affects sock_close() with a parallel sockfs_setattr() in
progress, which is not common.
Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.")
Reported-by: shankarapailoor <shankarapailoor@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull cifs fixes from Steve French:
- one smb3 (ACL related) fix for stable
- one SMB3 security enhancement (when mounting -t smb3 forbid less
secure dialects)
- some RDMA and compounding fixes
* tag '4.18-fixes-smb3' of git://git.samba.org/sfrench/cifs-2.6:
cifs: fix a buffer leak in smb2_query_symlink
smb3: do not allow insecure cifs mounts when using smb3
CIFS: Fix NULL ptr deref
CIFS: fix encryption in SMB3.1.1
CIFS: Pass page offset for encrypting
CIFS: Pass page offset for calculating signature
CIFS: SMBD: Support page offset in memory registration
CIFS: SMBD: Support page offset in RDMA recv
CIFS: SMBD: Support page offset in RDMA send
CIFS: When sending data on socket, pass the correct page offset
CIFS: Introduce helper function to get page offset and length in smb_rqst
CIFS: Calculate the correct request length based on page offset and tail size
cifs: For SMB2 security informaion query, check for minimum sized security descriptor instead of sizeof FileAllInformation class
CIFS: Fix signing for SMB2/3
Update the driver version to 12.0.0.4
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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