This patch ensures that the advertised link speeds are configured
for X553 KR/KX backplane. Without this patch the link remains at
1G when resuming from low power after being downshifted by LPLU.
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Once device_register is called for a device its attributes might be
accessed. As the callbacks of a lcd device's attributes make use of the
lcd_ops, the respective member must be setup before calling
device_register.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pseudo DMA transfer codes in VX222 and VX-pocket driver have a
slight bug where they check the buffer boundary wrongly, and may
overflow. Also, the zero sample count might be handled badly for the
playback (although it shouldn't happen in theory). This patch
addresses these issues.
The update of stream costs significantly, and we should avoid it
unless the stream really has started. Check pipe->running flag
instead of pipe->prepared.
Clear the VendorVersion in the PLOGI/PLOGI ACC payload
Vendor version info may have been set on fabric login. Before sending
PLOGI payloads, ensure that it's cleared.
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> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct issue leading to oops during link reset. Missing vport pointer.
[mkp: fixed typo]
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> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct host name in symbolic_name field of nameserver registrations
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> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
FCoE VPort enable-disable does not bring up the VPort.
VPI structure needed to be initialized before being re-registered.
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> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On loosely ordered memory systems (PPC for example), the WQE elements
were being updated in memory, but not necessarily flushed before the
separate doorbell was written to hw which would cause hw to dma the
WQE element. Thus, the hardware occasionally received partially
updated WQE data.
Add the memory barrier after updating the WQE memory.
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> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds the __irq_entry annotation to the default x86
platform IRQ handlers. ftrace's function_graph tracer uses the
__irq_entry annotation to notify the entry and return of IRQ
handlers.
Several lifecycle events in the rtl8188eu driver are logged using the
DBG_88E_LEVEL macro from rtw_debug.h, which is tagged as ERROR
regardless of the actual level. Below are dmesg excerpts after loading
and unloading the module, the messages are misleading as there was no
error.
For TCP sockets, TX timestamps are only captured when the user data
is successfully and fully written to the socket. In many cases,
however, TCP writes can be partial for which no timestamp is
collected.
Collect timestamps whenever any user data is (fully or partially)
copied into the socket. Pass tcp_write_queue_tail to tcp_tx_timestamp
instead of the local skb pointer since it can be set to NULL on
the error path.
Note that tcp_write_queue_tail can be NULL, even if bytes have been
copied to the socket. This is because acknowledgements are being
processed in tcp_sendmsg(), and by the time tcp_tx_timestamp is
called tcp_write_queue_tail can be NULL. For such cases, this patch
does not collect any timestamps (i.e., it is best-effort).
This patch is written with suggestions from Willem de Bruijn and
Eric Dumazet.
Change-log V1 -> V2:
- Use sockc.tsflags instead of sk->sk_tsflags.
- Use the same code path for normal writes and errors.
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UFS device requires to perform bkops (back ground operations) periodically
but host can control (via auto-bkops parameter of device) when device can
perform bkops based on its performance requirements. In general, host
would like to enable the device's auto-bkops only when it's not doing any
regular data transfer but sometimes device may not behave properly if host
keeps the auto-bkops disabled. This change adds the capability to let the
device auto-bkops always enabled except suspend.
If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.
Export the module alias information using the MODULE_DEVICE_TABLE() macro.
Before this patch:
$ modinfo drivers/scsi/ufs/ufs-qcom.ko | grep alias
$
After this patch:
$ modinfo drivers/scsi/ufs/ufs-qcom.ko | grep alias
alias: of:N*T*Cqcom,ufshcC*
alias: of:N*T*Cqcom,ufshc
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Similar to ixgbe, when an interface is part of a namespace it is
possible that igb_close() may be called while __igb_shutdown() is
running which ends up in a double free WARN and/or a BUG in
free_msi_irqs().
Extend the rtnl_lock() to protect the call to netif_device_detach() and
igb_clear_interrupt_scheme() in __igb_shutdown() and check for
netif_device_present() to avoid calling igb_clear_interrupt_scheme() a
second time in igb_close().
Also extend the rtnl lock in igb_resume() to netif_device_attach().
Signed-off-by: Todd Fujinaka <todd.fujinaka@intel.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several people have reported firmware leaving the I210/I211 PHY's page
select register set to something other than the default of zero. This
causes the first accesses, PHY_IDx register reads, to access something
else, resulting in device probe failure:
igb: Intel(R) Gigabit Ethernet Network Driver - version 5.4.0-k
igb: Copyright (c) 2007-2014 Intel Corporation.
igb: probe of 0000:01:00.0 failed with error -2
This problem began for them after a previous patch I submitted was
applied:
I personally experienced this problem after attempting to PXE boot from
I210 devices using this firmware:
Intel(R) Boot Agent GE v1.5.78
Copyright (C) 1997-2014, Intel Corporation
Resetting the PHY before reading from it, ensures the page select
register is in its default state and doesn't make assumptions about
the PHY's register set before the PHY has been probed.
Cc: Matwey V. Kornilov <matwey@sai.msu.ru> Cc: Chris Arges <carges@vectranetworks.com> Cc: Jochen Henneberg <jh@henneberg-systemdesign.com> Signed-off-by: Aaron Sierra <asierra@xes-inc.com> Tested-by: Matwey V. Kornilov <matwey@sai.msu.ru> Tested-by: Chris J Arges <christopherarges@gmail.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here, If devm_ioremap_nocache will fail. It will return NULL.
Kernel can run into a NULL-pointer dereference. This error check
will avoid NULL pointer dereference.
Note that the value is still glitchy during off mode transitions as documented
in spz319f.pdf "Advisory 1.45". It's best to use external pulls instead of
relying on the internal ones for off mode and even then anything pulled up
will get driven down momentarily on off mode restore for GPIO banks other
than bank1.
Multiple IES API resets can cause a race condition where the mailbox
interrupt request bits can be cleared before being handled. This can
leave certain mailbox messages from the PF to be untreated and the PF
will enter in some inactive state. If this situation occurs, the IES API
will initiate a mailbox version reset which, then, trigger a mailbox
state change. Once this mailbox transition occurs (from OPEN to CONNECT
state), a request for reset will be returned.
This ensures that PF will undergo a reset whenever IES API encounters an
unknown global mailbox interrupt event or whenever the IES API
terminates.
extcon-palmas must be child of palmas and expects parent's
drvdata to be valid. Check for non NULL parent drvdata and
fail if it is NULL. Not doing so will result in a NULL
pointer dereference later in the probe() parent drvdata
is NULL (e.g. misplaced extcon-palmas node in device tree).
This patch removes the potential problem of extcon_register_notifier()
when edev parameter is NULL. When edev is NULL, this function returns
the first extcon device which includes the sepecific external connector
of second paramter. But, it don't guarantee the same operation in all cases.
To remove this confusion and potential problem, this patch fixes it.
There's been numerous reported instances where BTUSB_QCA_ROME
bluetooth controllers stop functioning upon resume from suspend. These
devices seem to be losing power during suspend. Patch will detect a status
change on resume and perform a reset.
Eric Biggers [Fri, 17 Nov 2017 19:50:27 +0000 (11:50 -0800)]
arm: crypto: reduce priority of bit-sliced AES cipher
[ Not upstream because this is a minimal fix for a bug where arm32
kernels can use a much slower implementation of AES than is actually
available, potentially forcing vendors to disable encryption on their
devices.]
All the aes-bs (bit-sliced) and aes-ce (cryptographic extensions)
algorithms had a priority of 300. This is undesirable because it means
an aes-bs algorithm may be used when an aes-ce algorithm is available.
The aes-ce algorithms have much better performance (up to 10x faster).
Fix it by decreasing the priority of the aes-bs algorithms to 250.
This was fixed upstream by commit cc477bf64573 ("crypto: arm/aes -
replace bit-sliced OpenSSL NEON code"), but it was just a small part of
a complete rewrite. This patch just fixes the priority bug for older
kernels.
Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
dvb_detach(arg) calls symbol_put_addr(arg), where arg should be a pointer
to a function. Right now a pointer to state->dib7000p_ops is passed to
dvb_detach(), which causes a BUG() in symbol_put_addr() as discovered by
syzkaller. Pass state->dib7000p_ops.set_wbd_ref instead.
Commit f4757af ("staging: panel: Fix single-open policy race condition")
introduced in 3.19-rc1 attempted to fix a race condition on the open, but
failed to properly do it and used to exit without restoring the semaphore.
This results in -EBUSY being returned after the first open error until
the module is reloaded or the system restarted (ie: consecutive to a
dual open resulting in -EBUSY or to a permission error).
Fixes: f4757af85 # 3.19-rc1 Cc: Mariusz Gorski <marius.gorski@gmail.com> Signed-off-by: Willy Tarreau <w@1wt.eu>
[wt: driver is in misc/panel in 4.9] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch drops two incorrect usages of tcm_qla2xxx_free_cmd()
during TMR ABORT within tcm_qla2xxx_handle_data_work() and
tcm_qla2xxx_aborted_task(), which where attempting to dispatch
into workqueue context to do tcm_qla2xxx_complete_free() and
subsequently invoke transport_generic_free_cmd().
This is incorrect because during TMR ABORT target-core will
drop the outstanding se_cmd->cmd_kref references once it has
quiesced the se_cmd via transport_wait_for_tasks(), and in
the case of qla2xxx it should not attempt to do it's own
transport_generic_free_cmd() once the abort has occured.
As reported by Pascal, this was originally manifesting as a
BUG_ON(cmd->cmd_in_wq) in qlt_free_cmd() during TMR ABORT,
with a LIO backend that had sufficently high enough WRITE
latency to trigger a host side TMR ABORT_TASK.
(v2: Drop the qla_tgt_cmd->write_pending_abort_comp changes,
as they will be addressed in a seperate series)
Reported-by: Pascal de Bruijn <p.debruijn@unilogic.nl> Tested-by: Pascal de Bruijn <p.debruijn@unilogic.nl> Cc: Pascal de Bruijn <p.debruijn@unilogic.nl> Reported-by: Lukasz Engel <lukasz.engel@softax.pl> Cc: Lukasz Engel <lukasz.engel@softax.pl> Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com> Cc: Quinn Tran <quinn.tran@cavium.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allocate a task management request structure for all task management
requests, including task reassignment. This change avoids that the
se_tmr->response assignment dereferences an uninitialized se_tmr
pointer.
Reported-by: Moshe David <mdavid@infinidat.com> Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Moshe David <mdavid@infinidat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Upon stopping an AP interface the driver disable INFRA mode effectively
setting the interface in IBSS mode. However, this may affect other
interfaces running in INFRA mode. For instance, if user creates and stops
hostap daemon on virtual interface, then association cannot work on
primary interface because default BSS has been set to IBSS mode in
firmware side. The IBSS mode should be set when cfg80211 changes the
interface.
Reviewed-by: Wright Feng <wright.feng@cypress.com> Signed-off-by: Chi-hsien Lin <Chi-Hsien.Lin@cypress.com>
[kvalo@codeaurora.org: rephased commit log based on discussion] Signed-off-by: Wright Feng <wright.feng@cypress.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Cc: Philipp Rosenberger <p.rosenberger@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_KEYS_COMPAT is defined in arch-specific Kconfigs and is missing for
several 64-bit architectures : mips, parisc, tile.
At the moment and for those architectures, calling in 32-bit userspace the
keyctl syscall would return an ENOSYS error.
This patch moves the CONFIG_KEYS_COMPAT option to security/keys/Kconfig, to
make sure the compatibility wrapper is registered by default for any 64-bit
architecture as long as it is configured with CONFIG_COMPAT.
[DH: Modified to remove arm64 compat enablement also as requested by Eric
Biggers]
Signed-off-by: Bilal Amarni <bilal.amarni@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
cc: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Cc: James Cowgill <james.cowgill@mips.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It was not a good idea. The custom hash table was a much better
fit for this purpose.
A fast lookup is not essential, in fact for most cases there is no lookup
at all because original tuple is not taken and can be used as-is.
What needs to be fast is insertion and deletion.
rhlist removal however requires a rhlist walk.
We can have thousands of entries in such a list if source port/addresses
are reused for multiple flows, if this happens removal requests are so
expensive that deletions of a few thousand flows can take several
seconds(!).
The advantages that we got from rhashtable are:
1) table auto-sizing
2) multiple locks
1) would be nice to have, but it is not essential as we have at
most one lookup per new flow, so even a million flows in the bysource
table are not a problem compared to current deletion cost.
2) is easy to add to custom hash table.
I tried to add hlist_node to rhlist to speed up rhltable_remove but this
isn't doable without changing semantics. rhltable_remove_fast will
check that the to-be-deleted object is part of the table and that
requires a list walk that we want to avoid.
Furthermore, using hlist_node increases size of struct rhlist_head, which
in turn increases nf_conn size.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821 Reported-by: Ivan Babrou <ibobrik@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
successful insert into the bysource hash sets IPS_SRC_NAT_DONE status bit
so we can check that instead of presence of nat extension which requires
extra deref.
Turns out not to be a good idea in the stable kernels for now as Patrick
writes:
As discussed for 4.4 stable queue this patch might break
existing machines, if they use a different pinmux configuration
with their own bootloader.
ALSA sequencer core has a mechanism to load the enumerated devices
automatically, and it's performed in an off-load work. This seems
causing some race when a sequencer is removed while the pending
autoload work is running. As syzkaller spotted, it may lead to some
use-after-free:
BUG: KASAN: use-after-free in snd_rawmidi_dev_seq_free+0x69/0x70
sound/core/rawmidi.c:1617
Write of size 8 at addr ffff88006c611d90 by task kworker/2:1/567
Before trying to use CDC union descriptor, try to validate whether that it
is sane by checking that intf->altsetting->extra is big enough and that
descriptor bLength is not too big and not too small.
If the usbtest driver encounters a device with an IN bulk endpoint but
no OUT bulk endpoint, it will try to dereference a NULL pointer
(out->desc.bEndpointAddress). The problem can be solved by adding a
missing test.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For the reinstall prevention, the code I had added compares the
whole key. It turns out though that iwlwifi firmware doesn't
provide the TKIP TX MIC key as it's not needed in client mode,
and thus the comparison will always return false.
For client mode, thus always zero out the TX MIC key part before
doing the comparison in order to avoid accepting the reinstall
of the key with identical encryption and RX MIC key, but not the
same TX MIC key (since the supplicant provides the real one.)
Fixes: fdf7cb4185b6 ("mac80211: accept key reinstall without changing anything") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a key is reinstalled we can reset the replay counters
etc. which can lead to nonce reuse and/or replay detection
being impossible, breaking security properties, as described
in the "KRACK attacks".
In particular, CVE-2017-13080 applies to GTK rekeying that
happened in firmware while the host is in D3, with the second
part of the attack being done after the host wakes up. In
this case, the wpa_supplicant mitigation isn't sufficient
since wpa_supplicant doesn't know the GTK material.
In case this happens, simply silently accept the new key
coming from userspace but don't take any action on it since
it's the same key; this keeps the PN replay counters intact.
Signed-off-by: Johannes Berg <johannes.berg@intel.com> Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ppp_release() tries to ensure that netdevices are unregistered before
decrementing the unit refcount and running ppp_destroy_interface().
This is all fine as long as the the device is unregistered by
ppp_release(): the unregister_netdevice() call, followed by
rtnl_unlock(), guarantee that the unregistration process completes
before rtnl_unlock() returns.
However, the device may be unregistered by other means (like
ppp_nl_dellink()). If this happens right before ppp_release() calling
rtnl_lock(), then ppp_release() has to wait for the concurrent
unregistration code to release the lock.
But rtnl_unlock() releases the lock before completing the device
unregistration process. This allows ppp_release() to proceed and
eventually call ppp_destroy_interface() before the unregistration
process completes. Calling free_netdev() on this partially unregistered
device will BUG():
------------[ cut here ]------------
kernel BUG at net/core/dev.c:8141!
invalid opcode: 0000 [#1] SMP
CPU: 1 PID: 1557 Comm: pppd Not tainted 4.14.0-rc2+ #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1.fc26 04/01/2014
We could set the ->needs_free_netdev flag on PPP devices and move the
ppp_destroy_interface() logic in the ->priv_destructor() callback. But
that'd be quite intrusive as we'd first need to unlink from the other
channels and units that depend on the device (the ones that used the
PPPIOCCONNECT and PPPIOCATTACH ioctls).
Instead, we can just let the netdevice hold a reference on its
ppp_file. This reference is dropped in ->priv_destructor(), at the very
end of the unregistration process, so that neither ppp_release() nor
ppp_disconnect_channel() can call ppp_destroy_interface() in the interim.
Reported-by: Beniamino Galvani <bgalvani@redhat.com> Fixes: 8cb775bc0a34 ("ppp: fix device unregistration upon netns deletion") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Davide found the following script triggers a NULL pointer
dereference:
ip l a name eth0 type dummy
tc q a dev eth0 parent :1 handle 1: htb
This is because for a freshly created netdevice noop_qdisc
is attached and when passing 'parent :1', kernel actually
tries to match the major handle which is 0 and noop_qdisc
has handle 0 so is matched by mistake. Commit 69012ae425d7
tries to fix a similar bug but still misses this case.
Handle 0 is not a valid one, should be just skipped. In
fact, kernel uses it as TC_H_UNSPEC.
Fixes: 69012ae425d7 ("net: sched: fix handling of singleton qdiscs with qdisc_hash") Fixes: 59cc1f61f09c ("net: sched:convert qdisc linked list to hashtable") Reported-by: Davide Caratti <dcaratti@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Eric Dumazet <edumazet@google.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now when migrating sock to another one in sctp_sock_migrate(), it only
resets owner sk for the data in receive queues, not the chunks on out
queues.
It would cause that data chunks length on the sock is not consistent
with sk sk_wmem_alloc. When closing the sock or freeing these chunks,
the old sk would never be freed, and the new sock may crash due to
the overflow sk_wmem_alloc.
Although listen() should have returned error when one TCP-style socket
is in connecting (I may fix this one in another patch), it could also
be reproduced by peeling off an assoc.
This issue is there since very beginning.
This patch is to reset owner sk for the chunks on out queues so that
sk sk_wmem_alloc has correct value after accept one sock or peeloff
an assoc to one sock.
Note that when resetting owner sk for chunks on outqueue, it has to
sctp_clear_owner_w/skb_orphan chunks before changing assoc->base.sk
first and then sctp_set_owner_w them after changing assoc->base.sk,
due to that sctp_wfree and it's callees are using assoc->base.sk.
Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the name argument of dev_get_valid_name() contains "%d", it will try
to assign it a unit number in __dev__alloc_name() and return either the
unit number (>= 0) or an error code (< 0).
Considering positive values as error values prevent tun device creations
relying this mechanism, therefor we should only consider negative values
as errors here.
Signed-off-by: Julien Gomes <julien@arista.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When receiving a Toobig icmpv6 packet, ip6gre_err would just set
tunnel dev's mtu, that's not enough. For skb_dst(skb)'s pmtu may
still be using the old value, it has no chance to be updated with
tunnel dev's mtu.
Jianlin found this issue by reducing route's mtu while running
netperf, the performance went to 0.
ip6ip6 and ip4ip6 tunnel can work well with this, as they lookup
the upper dst and update_pmtu it's pmtu or icmpv6_send a Toobig
to upper socket after setting tunnel dev's mtu.
We couldn't do that for ip6_gre, as gre's inner packet could be
any protocol, it's difficult to handle them (like lookup upper
dst) in a good way.
So this patch is to fix it by updating skb_dst(skb)'s pmtu when
dev->mtu < skb_dst(skb)'s pmtu in tx path. It's safe to do this
update there, as usually dev->mtu <= skb_dst(skb)'s pmtu and no
performance regression can be caused by this.
Fixes: c12b395a4664 ("gre: Support GRE over IPv6") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The similar fix in patch 'ipip: only increase err_count for some
certain type icmp in ipip_err' is needed for ip6gre_err.
In Jianlin's case, udp netperf broke even when receiving a TooBig
icmpv6 packet.
Fixes: c12b395a4664 ("gre: Support GRE over IPv6") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
t->err_count is used to count the link failure on tunnel and an err
will be reported to user socket in tx path if t->err_count is not 0.
udp socket could even return EHOSTUNREACH to users.
Since commit fd58156e456d ("IPIP: Use ip-tunneling code.") removed
the 'switch check' for icmp type in ipip_err(), err_count would be
increased by the icmp packet with ICMP_EXC_FRAGTIME code. an link
failure would be reported out due to this.
In Jianlin's case, when receiving ICMP_EXC_FRAGTIME a icmp packet,
udp netperf failed with the err:
send_data: data send error: No route to host (errno 113)
We expect this error reported from tunnel to socket when receiving
some certain type icmp, but not ICMP_EXC_FRAGTIME, ICMP_SR_FAILED
or ICMP_PARAMETERPROB ones.
This patch is to bring 'switch check' for icmp type back to ipip_err
so that it only reports link failure for the right type icmp, just as
in ipgre_err() and ipip6_err().
Fixes: fd58156e456d ("IPIP: Use ip-tunneling code.") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Double free of skb_array in tap module is causing kernel panic. When
tap_set_queue() fails we free skb_array right away by calling
skb_array_cleanup(). However, later on skb_array_cleanup() is called
again by tap_sock_destruct through sock_put(). This patch fixes that
issue.
Fixes: 362899b8725b35e3 (macvtap: switch to use skb array) Signed-off-by: Girish Moodalbail <girish.moodalbail@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
socket_diag shows information only about sockets from a namespace where
a diag socket lives.
But if we request information about one unix socket, the kernel don't
check that its netns is matched with a diag socket namespace, so any
user can get information about any unix socket in a system. This looks
like a bug.
v2: add a Fixes tag
Fixes: 51d7cccf0723 ("net: make sock diag per-namespace") Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In my first attempt to fix the lockdep splat, I forgot we could
enter inet_csk_route_req() with a freshly allocated request socket,
for which refcount has not yet been elevated, due to complex
SLAB_TYPESAFE_BY_RCU rules.
We either are in rcu_read_lock() section _or_ we own a refcount on the
request.
Correct RCU verb to use here is rcu_dereference_check(), although it is
not possible to prove we actually own a reference on a shared
refcount :/
In v2, I added ireq_opt_deref() helper and use in three places, to fix other
possible splats.
Thread running inet_csk_route_req() owns a reference on the request
socket, so we have the guarantee ireq->ireq_opt wont be changed or
freed.
lockdep can enforce this invariant for us.
Fixes: c92e8c02fe66 ("tcp/dccp: fix ireq->opt races") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 9b9742022888 ("sctp: support ipv6 nonlocal bind")
introduced support for the above options as v4 sctp did,
so patched sctp_v6_available().
In the v4 implementation it's enough, because
sctp_inet_bind_verify() just returns with sctp_v4_available().
However sctp_inet6_bind_verify() has an extra check before that
for link-local scope_id, which won't respect the above options.
Added the checks before calling ipv6_chk_addr(), but
not before the validation of scope_id.
after (w/ both options):
./v6test fe80::10 sctp
bind success, errno: 0 (Success)
Signed-off-by: Laszlo Toth <laszlth@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When syzkaller team brought us a C repro for the crash [1] that
had been reported many times in the past, I finally could find
the root cause.
If FlowLabel info is merged by fl6_merge_options(), we leave
part of the opt_space storage provided by udp/raw/l2tp with random value
in opt_space.tot_len, unless a control message was provided at sendmsg()
time.
Then ip6_setup_cork() would use this random value to perform a kzalloc()
call. Undefined behavior and crashes.
Fix is to properly set tot_len in fl6_merge_options()
At the same time, we can also avoid consuming memory and cpu cycles
to clear it, if every option is copied via a kmemdup(). This is the
change in ip6_setup_cork().
Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Syzkaller stumbled upon a way to trigger
WARNING: CPU: 1 PID: 13881 at net/core/sock_reuseport.c:41
reuseport_alloc+0x306/0x3b0 net/core/sock_reuseport.c:39
There are two initialization paths for the sock_reuseport structure in a
socket: Through the udp/tcp bind paths of SO_REUSEPORT sockets or through
SO_ATTACH_REUSEPORT_[CE]BPF before bind. The existing implementation
assumedthat the socket lock protected both of these paths when it actually
only protects the SO_ATTACH_REUSEPORT path. Syzkaller triggered this
double allocation by running these paths concurrently.
This patch moves the check for double allocation into the reuseport_alloc
function which is protected by a global spin lock.
Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection") Fixes: c125e80b8868 ("soreuseport: fast reuseport TCP socket selection") Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzkaller got crashes in packet_getsockopt() processing
PACKET_ROLLOVER_STATS command while another thread was managing
to change po->rollover
Using RCU will fix this bug. We might later add proper RCU annotations
for sparse sake.
In v2: I replaced kfree(rollover) in fanout_add() to kfree_rcu()
variant, as spotted by John.
Fixes: a9b6391814d5 ("packet: rollover statistics") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: John Sperbeck <jsperbeck@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzkaller found another bug in DCCP/TCP stacks [1]
For the reasons explained in commit ce1050089c96 ("tcp/dccp: fix
ireq->pktopts race"), we need to make sure we do not access
ireq->opt unless we own the request sock.
Note the opt field is renamed to ireq_opt to ease grep games.
[1]
BUG: KASAN: use-after-free in ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474
Read of size 1 at addr ffff8801c951039c by task syz-executor5/3295
Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now sctp processes icmp redirect packet in sctp_icmp_redirect where
it calls sctp_transport_dst_check in which tp->dst can be released.
The problem is before calling sctp_transport_dst_check, it doesn't
check sock_owned_by_user, which means tp->dst could be freed while
a process is accessing it with owning the socket.
An use-after-free issue could be triggered by this.
This patch is to fix it by checking sock_owned_by_user before calling
sctp_transport_dst_check in sctp_icmp_redirect, so that it would not
release tp->dst if users still hold sock lock.
Besides, the same issue fixed in commit 45caeaa5ac0b ("dccp/tcp: fix
routing redirect race") on sctp also needs this check.
Fixes: 55be7a9c6074 ("ipv4: Add redirect support to all protocol icmp error handlers") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
register_netdevice() could fail early when we have an invalid
dev name, in which case ->ndo_uninit() is not called. For tun
device, this is a problem because a timer etc. are already
initialized and it expects ->ndo_uninit() to clean them up.
We could move these initializations into a ->ndo_init() so
that register_netdevice() knows better, however this is still
complicated due to the logic in tun_detach().
Therefore, I choose to just call dev_get_valid_name() before
register_netdevice(), which is quicker and much easier to audit.
And for this specific case, it is already enough.
Fixes: 96442e42429e ("tuntap: choose the txq based on rxq") Reported-by: Dmitry Alexeev <avekceeb@gmail.com> Cc: Jason Wang <jasowang@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When pppol2tp_session_ioctl() is called by pppol2tp_tunnel_ioctl(),
the session may be unconnected. That is, it was created by
pppol2tp_session_create() and hasn't been connected with
pppol2tp_connect(). In this case, ps->sock is NULL, so we need to check
for this case in order to avoid dereferencing a NULL pointer.
Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault <g.nault@alphalink.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on SNMP values provided by Roman, Yuchung made the observation
that some crashes in tcp_sacktag_walk() might be caused by MTU probing.
Looking at tcp_mtu_probe(), I found that when a new skb was placed
in front of the write queue, we were not updating tcp highest sack.
If one skb is freed because all its content was copied to the new skb
(for MTU probing), then tp->highest_sack could point to a now freed skb.
Bad things would then happen, including infinite loops.
This patch renames tcp_highest_sack_combine() and uses it
from tcp_mtu_probe() to fix the bug.
Note that I also removed one test against tp->sacked_out,
since we want to replace tp->highest_sack regardless of whatever
condition, since keeping a stale pointer to freed skb is a recipe
for disaster.
Fixes: a47e5a988a57 ("[TCP]: Convert highest_sack to sk_buff to allow direct access") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Reported-by: Roman Gushchin <guro@fb.com> Reported-by: Oleksandr Natalenko <oleksandr@natalenko.name> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If for some reason, the newly allocated child need to be freed,
we will call cgroup_put() (via sk_free_unlock_clone()) while the
corresponding cgroup_get() was not yet done, and we will free memory
too soon.
Fixes: d979a39d7242 ("cgroup: duplicate cgroup reference when cloning sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It turns out that multiple places can call netlink_dump(), which means
it's still possible to dereference partially initialized values in
dump() that were the result of a faulty returned start().
This fixes the issue by calling start() _before_ setting cb_running to
true, so that there's no chance at all of hitting the dump() function
through any indirect paths.
It also moves the call to start() to be when the mutex is held. This has
the nice side effect of serializing invocations to start(), which is
likely desirable anyway. It also prevents any possible other races that
might come out of this logic.
In testing this with several different pieces of tricky code to trigger
these issues, this commit fixes all avenues that I'm aware of.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Johannes Berg <johannes@sipsolutions.net> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the (unlikely) event fixup_permanent_addr() returns a failure,
addrconf_permanent_addr() calls ipv6_del_addr() without the
mandatory call to in6_ifa_hold(), leading to a refcount error,
spotted by syzkaller :
WARNING: CPU: 1 PID: 3142 at lib/refcount.c:227 refcount_dec+0x4c/0x50
lib/refcount.c:227
Kernel panic - not syncing: panic_on_warn set ...
Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Ahern <dsahern@gmail.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Syzkaller found several variants of the lockup below by setting negative
values with the TUNSETSNDBUF ioctl. This patch adds a sanity check
to both the tun and tap versions of this ioctl.
When gso_size reset to zero for the tail segment in skb_segment(), later
in ipv6_gso_segment(), __skb_udp_tunnel_segment() and gre_gso_segment()
we will get incorrect results (payload length, pcsum) for that segment.
inet_gso_segment() already has a check for gso_size before calculating
payload.
The issue was found with LTP vxlan & gre tests over ixgbe NIC.
Fixes: 07b26c9454a2 ("gso: Support partial splitting at the frag_list pointer") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the TSC has constant frequency then the delay calibration can be skipped
when it has been calibrated for a package already. This is checked in
calibrate_delay_is_known(), but that function is buggy in two aspects:
which is obviously the reverse of the intended check and the check for the
sibling mask cannot work either because the topology links have not been
set up yet.
Correct the condition and move the call to set_cpu_sibling_map() before
invoking calibrate_delay() so the sibling check works correctly.
[ tglx: Rewrote changelong ]
Fixes: c25323c07345 ("x86/tsc: Use topology functions") Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: bob.picco@oracle.com Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Link: https://lkml.kernel.org/r/20171028001100.26603-1-pasha.tatashin@oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The D_CAN controller doesn't provide a triple sampling mode, so don't set
the CAN_CTRLMODE_3_SAMPLES flag in ctrlmode_supported. Currently enabling
triple sampling is a no-op.
Signed-off-by: Richard Schütz <rschuetz@uni-koblenz.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The CANFD transmitter delay calculation formula was updated in the
latest software drop from IFI and improves the behavior of the IFI
CANFD core during bitrate switching. Use the new formula to improve
stability of the CANFD operation.
Signed-off-by: Marek Vasut <marex@denx.de> Cc: Markus Marb <markus@marb.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SUN4Is CAN IP has a 64 byte deep FIFO buffer. If the buffer is not
drained fast enough (overrun) it's getting mangled. Already received
frames are dropped - the data can't be restored.
Signed-off-by: Gerhard Bertelsmann <info@gerhard-bertelsmann.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I've found that by just turning the chip on and off via the
POWER_DOWN register, I end up getting i2c_transfer errors on
HiKey.
Investigating further, it turns out that some of the register
state in hardware is getting lost, as the device registers are
reset when the chip is powered down.
Thus this patch simply re-writes the i2c address to the
ADV7511_REG_EDID_I2C_ADDR register to ensure its properly set
before we try to read the EDID data.
Thus this patch changes the EDID probing logic so that we
re-use the __adv7511_power_on/off() calls instead of duplciating
logic.
This does change behavior slightly as it adds the HPD signal
pulse to the EDID probe path, but Archit has had a patch to
add HPD signal pulse to the EDID probe path before, so this
should address the cases where that helped. Another difference
is that regcache_mark_dirty() is also called in the power off
path once EDID is probed.
This is an extension of Commit 7c20d213dd3c ("drm/vmwgfx: Work
around mode set failure in 2D VMs")
With Wayland desktop and atomic mode set, during the mode setting
process there is a moment when two framebuffer sized surfaces
are being pinned. This was not an issue with Xorg.
Since this only happens during a mode change, there should be no
performance impact by increasing allowable mem_size.
rbd_img_obj_exists_submit() and rbd_img_obj_parent_read_full() are on
the writeback path for cloned images -- we attempt a stat on the parent
object to see if it exists and potentially read it in to call copyup.
GFP_NOIO should be used instead of GFP_KERNEL here.
When called from prom init code, ar7_gpio_init() will fail as it will
call gpiochip_add() which relies on a working kmalloc() to alloc
the gpio_desc array and kmalloc is not useable yet at prom init time.
Move ar7_gpio_init() to ar7_register_devices() (a device_initcall)
where kmalloc works.
The dapm components are now handled by the ALSA SoC SPDIF DIT driver
so can be removed.
Signed-off-by: Marcus Cooper <codekipper@gmail.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some distributions (Debian, OpenSUSE) have a udev rule in place to cancel
all fallback mechanism uevents immediately. This would obviously
make it hard to test against the fallback mechanism test interface,
so we need to check for this.
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Error that we expect should not be spilled to stdout.
Without this we get:
./fw_filesystem.sh: line 58: printf: write error: Invalid argument
./fw_filesystem.sh: line 63: printf: write error: No such device
./fw_filesystem.sh: line 69: echo: write error: No such file or directory
./fw_filesystem.sh: filesystem loading works
./fw_filesystem.sh: async filesystem loading works
With it:
./fw_filesystem.sh: filesystem loading works
./fw_filesystem.sh: async filesystem loading works
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 6f542ebeaee0 ("MIPS: Fix race on setting and getting
cpu_online_mask") effectively reverted commit 8f46cca1e6c06 ("MIPS: SMP:
Fix possibility of deadlock when bringing CPUs online") and thus has
reinstated the possibility of deadlock.
The commit was based on testing of kernel v4.4, where the CPU hotplug
core code issued a BUG() if the starting CPU is not marked online when
the boot CPU returns from __cpu_up. The commit fixes this race (in
v4.4), but re-introduces the deadlock situation.
As noted in the commit message, upstream differs in this area. Commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up")
adds a completion event in the CPU hotplug core code, making this race
impossible. However, people were unhappy with relying on the core code
to do the right thing.
To address the issues both commits were trying to fix, add a second
completion event in the MIPS smp hotplug path. It removes the
possibility of a race, since the MIPS smp hotplug code now synchronises
both the boot and secondary CPUs before they return to the hotplug core
code. It also addresses the deadlock by ensuring that the secondary CPU
is not marked online before it's counters are synchronised.
This fix should also be backported to fix the race condition introduced
by the backport of commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of
deadlock when bringing CPUs online"), through really that race only
existed before commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu
bring itself fully up").
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Fixes: 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask") CC: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Patchwork: https://patchwork.linux-mips.org/patch/17376/ Signed-off-by: James Hogan <jhogan@kernel.org>
[jhogan@kernel.org: Backported 4.1..4.9] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>