For SYSTEM chunks, despite the regular chunk item size limit, there is
another limit due to system chunk array size.
The extra limit was removed in a refactoring, so add it back.
Fixes: e3ecdb3fde ("btrfs: factor out devs_max setting in __btrfs_alloc_chunk")
CC: stable@vger.kernel.org # 5.3+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We currently assume that submissions from the sqthread are successful,
and if IO polling is enabled, we use that value for knowing how many
completions to look for. But if we overflowed the CQ ring or some
requests simply got errored and already completed, they won't be
available for polling.
For the case of IO polling and SQTHREAD usage, look at the pending
poll list. If it ever hits empty then we know that we don't have
anymore pollable requests inflight. For that case, simply reset
the inflight count to zero.
Reported-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We currently use the ring values directly, but that can lead to issues
if the application is malicious and changes these values on our behalf.
Created in-kernel cached versions of them, and just overwrite the user
side when we update them. This is similar to how we treat the sq/cq
ring tail/head updates.
Reported-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
io_ring_submit() finalises with
1. io_commit_sqring(), which releases sqes to the userspace
2. Then calls to io_queue_link_head(), accessing released head's sqe
Reorder them.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
io_sq_thread() processes sqes by 8 without considering links. As a
result, links will be randomely subdivided.
The easiest way to fix it is to call io_get_sqring() inside
io_submit_sqes() as do io_ring_submit().
Downsides:
1. This removes optimisation of not grabbing mm_struct for fixed files
2. It submitting all sqes in one go, without finer-grained sheduling
with cq processing.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is a bug, where failed linked requests are returned not with
specified @user_data, but with garbage from a kernel stack.
The reason is that io_fail_links() uses req->user_data, which is
uninitialised when called from io_queue_sqe() on fail path.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Support for the kernel as Xen 32-bit PV guest will soon be removed.
Issue a warning when booted as such.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pull the second lot of irqchip updates for 5.4 from Marc Zyngier:
- Sifive PLIC: force driver to skip non-relevant contexts
- GICv4: Don't send VMOVP commands to ITSs that don't have
this vPE mapped
This reorganization will allow us to call kvm_arch_destroy_vm in the
event that kvm_create_vm fails after calling kvm_arch_init_vm.
Suggested-by: Junaid Shahid <junaids@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Junaid Shahid <junaids@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Recent cleanup in the way EEH support is added to a device causes a
kernel oops when the cxl driver probes a device and creates virtual
devices discovered on the FPGA:
BUG: Kernel NULL pointer dereference at 0x000000a0
Faulting instruction address: 0xc000000000048070
Oops: Kernel access of bad area, sig: 7 [#1]
...
NIP eeh_add_device_late.part.9+0x50/0x1e0
LR eeh_add_device_late.part.9+0x3c/0x1e0
Call Trace:
_dev_info+0x5c/0x6c (unreliable)
pnv_pcibios_bus_add_device+0x60/0xb0
pcibios_bus_add_device+0x40/0x60
pci_bus_add_device+0x30/0x100
pci_bus_add_devices+0x64/0xd0
cxl_pci_vphb_add+0xe0/0x130 [cxl]
cxl_probe+0x504/0x5b0 [cxl]
local_pci_probe+0x6c/0x110
work_for_cpu_fn+0x38/0x60
The root cause is that those cxl virtual devices don't have a
representation in the device tree and therefore no associated pci_dn
structure. In eeh_add_device_late(), pdn is NULL, so edev is NULL and
we oops.
We never had explicit support for EEH for those virtual devices.
Instead, EEH events are reported to the (real) pci device and handled
by the cxl driver. Which can then forward to the virtual devices and
handle dependencies. The fact that we try adding EEH support for the
virtual devices is new and a side-effect of the recent cleanup.
This patch fixes it by skipping adding EEH support on powernv for
devices which don't have a pci_dn structure.
The cxl driver doesn't create virtual devices on pseries so this patch
doesn't fix it there intentionally.
Fixes: b905f8cdca ("powerpc/eeh: EEH for pSeries hot plug")
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191016162833.22509-1-fbarrat@linux.ibm.com
Modify plic_init() to skip .dts interrupt contexts other
than supervisor external interrupt.
The .dts entry for plic may specify multiple interrupt contexts.
For example, it may assign two entries IRQ_M_EXT and IRQ_S_EXT,
in that order, to the same interrupt controller. This patch
modifies plic_init() to skip the IRQ_M_EXT context since
IRQ_S_EXT is currently the only supported context.
If IRQ_M_EXT is not skipped, plic_init() will report "handler
already present for context" when it comes across the IRQ_S_EXT
context in the next iteration of its loop.
Without this patch, .dts would have to be edited to replace the
value of IRQ_M_EXT with -1 for it to be skipped.
Signed-off-by: Alan Mikhak <alan.mikhak@sifive.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # arch/riscv
Link: https://lkml.kernel.org/r/1571933503-21504-1-git-send-email-alan.mikhak@sifive.com
Add a callback to configure TDM settings for the Tegra30 I2S ASoC 'platform'
driver.
Signed-off-by: Edward Cragg <edward.cragg@codethink.co.uk>
[ben.dooks@codethink.co.uk: merge fix for power management]
[ben.dooks@codethink.co.uk: add review change for fsync of 1 clock]
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20191018154833.7560-2-ben.dooks@codethink.co.uk
Signed-off-by: Mark Brown <broonie@kernel.org>
for_each_dpcm_xx() macro is using "dpcm" as parameter (1),
but, it is also struct member (2).
#define for_each_dpcm_fe(be, stream, dpcm) \
list_for_each_entry(dpcm, &(be)->dpcm[stream]...)
^^^^(1) ^^^^(2)
Thus, it will be compile error if user not used "dpcm" as parameter
for_each_dpcm_fe(be, stream, dp)
^^
This patch fixup it.
Reported-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87tv7x7idx.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The tegra3 audio can support 24 and 32 bit sample sizes so add the
option to the tegra30_i2s_hw_params to configure the S24_LE or S32_LE
formats when requested.
Signed-off-by: Edward Cragg <edward.cragg@codethink.co.uk>
[ben.dooks@codethink.co.uk: fixup merge of 24 and 32bit]
[ben.dooks@codethink.co.uk: add pm calls around ytdm config]
[ben.dooks@codethink.co.uk: drop debug printing to dev_dbg]
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20191018154833.7560-3-ben.dooks@codethink.co.uk
Signed-off-by: Mark Brown <broonie@kernel.org>
Keeping the IRQ chip definition static shares it with multiple instances
of the GPIO chip in the system. This is bad and now we get this warning
from GPIO library:
"detected irqchip that is shared with multiple gpiochips: please fix the driver."
Hence, move the IRQ chip definition from being driver static into the struct
intel_pinctrl. So a unique IRQ chip is used for each GPIO chip instance.
This patch is heavily based on the attachment to the bug by Christoph Marz.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=202543
Fixes: 6e08d6bbeb ("pinctrl: Add Intel Cherryview/Braswell pin controller support")
Depends-on: 83b9dc1131 ("pinctrl: cherryview: Associate IRQ descriptors to irqdomain")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The _PPC change notifications from the platform firmware are per-CPU,
so acpi_processor_ppc_init() needs to add a frequency QoS request
for each CPU covered by a cpufreq policy to take all of them into
account.
Even though ACPI thermal control of CPUs sets frequency limits
per processor package, it also needs a frequency QoS request for each
CPU in a cpufreq policy in case some of them are taken offline and
the frequency limit needs to be set through the remaining online
ones (this is slightly excessive, because all CPUs covered by one
cpufreq policy will set the same frequency limit through their QoS
requests, but it is not incorrect).
Modify the code in accordance with the above observations.
Fixes: d15ce41273 ("ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Properly save and restore all top PLL related configuration registers
during suspend/resume cycle. So far driver only handled EPLL and RPLL
clocks, all other were reset to default values after suspend/resume cycle.
This caused for example lower G3D (MALI Panfrost) performance after system
resume, even if performance governor has been selected.
Reported-by: Reported-by: Marian Mihailescu <mihailescu2m@gmail.com>
Fixes: 773424326b ("clk: samsung: exynos5420: add more registers to restore list")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
The I2C multiplexer used on ls1028aqds is PCA9547, not PCA9847.
If the wrong compatible was used, this chip will not be able to
be probed correctly and hence fail to work.
Signed-off-by: Yuantian Tang <andy.tang@nxp.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Fixes: 8897f3255c ("arm64: dts: Add support for NXP LS1028A SoC")
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
if the second call of should_expire() in there ends up
grabbing and returning a new reference to dentry, we need
to drop it before continuing.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There's a deadlock that is possible and can easily be seen with
a test where multiple readers open/read/close of the same file
and a disruption occurs causing reconnect. The deadlock is due
a reader thread inside cifs_strict_readv calling down_read and
obtaining lock_sem, and then after reconnect inside
cifs_reopen_file calling down_read a second time. If in
between the two down_read calls, a down_write comes from
another process, deadlock occurs.
CPU0 CPU1
---- ----
cifs_strict_readv()
down_read(&cifsi->lock_sem);
_cifsFileInfo_put
OR
cifs_new_fileinfo
down_write(&cifsi->lock_sem);
cifs_reopen_file()
down_read(&cifsi->lock_sem);
Fix the above by changing all down_write(lock_sem) calls to
down_write_trylock(lock_sem)/msleep() loop, which in turn
makes the second down_read call benign since it will never
block behind the writer while holding lock_sem.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Suggested-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed--by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Currently the code assumes that if a file info entry belongs
to lists of open file handles of an inode and a tcon then
it has non-zero reference. The recent changes broke that
assumption when putting the last reference of the file info.
There may be a situation when a file is being deleted but
nothing prevents another thread to reference it again
and start using it. This happens because we do not hold
the inode list lock while checking the number of references
of the file info structure. Fix this by doing the proper
locking when doing the check.
Fixes: 487317c994 ("cifs: add spinlock for the openFileList to cifsInodeInfo")
Fixes: cb248819d2 ("cifs: use cifsInodeInfo->open_file_lock while iterating to avoid a panic")
Cc: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When the client hits reconnect it iterates over the mid
pending queue marking entries for retry and moving them
to a temporary list to issue callbacks later without holding
GlobalMid_Lock. In the same time there is no guarantee that
mids can't be removed from the temporary list or even
freed completely by another thread. It may cause a temporary
list corruption:
[ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469
[ 430.464668] ------------[ cut here ]------------
[ 430.466569] kernel BUG at lib/list_debug.c:51!
[ 430.468476] invalid opcode: 0000 [#1] SMP PTI
[ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19
[ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55
...
[ 430.510426] Call Trace:
[ 430.511500] cifs_reconnect+0x25e/0x610 [cifs]
[ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs]
[ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs]
[ 430.517452] ? try_to_wake_up+0x212/0x650
[ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs]
[ 430.521086] ? allocate_buffers+0x66/0x120 [cifs]
[ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs]
[ 430.525116] kthread+0xfb/0x130
[ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs]
[ 430.528514] ? kthread_park+0x90/0x90
[ 430.530019] ret_from_fork+0x35/0x40
Fix this by obtaining extra references for mids being retried
and marking them as MID_DELETED which indicates that such a mid
has been dequeued from the pending list.
Also move mid cleanup logic from DeleteMidQEntry to
_cifs_mid_q_entry_release which is called when the last reference
to a particular mid is put. This allows to avoid any use-after-free
of response buffers.
The patch needs to be backported to stable kernels. A stable tag
is not mentioned below because the patch doesn't apply cleanly
to any actively maintained stable kernel.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When rdmacm module is not loaded, and when netlink message is received to
get char device info, it results into a deadlock due to recursive locking
of rdma_nl_mutex with the below call sequence.
[..]
rdma_nl_rcv()
mutex_lock()
[..]
rdma_nl_rcv_msg()
ib_get_client_nl_info()
request_module()
iw_cm_init()
rdma_nl_register()
mutex_lock(); <- Deadlock, acquiring mutex again
Due to above call sequence, following call trace and deadlock is observed.
kernel: __mutex_lock+0x35e/0x860
kernel: ? __mutex_lock+0x129/0x860
kernel: ? rdma_nl_register+0x1a/0x90 [ib_core]
kernel: rdma_nl_register+0x1a/0x90 [ib_core]
kernel: ? 0xffffffffc029b000
kernel: iw_cm_init+0x34/0x1000 [iw_cm]
kernel: do_one_initcall+0x67/0x2d4
kernel: ? kmem_cache_alloc_trace+0x1ec/0x2a0
kernel: do_init_module+0x5a/0x223
kernel: load_module+0x1998/0x1e10
kernel: ? __symbol_put+0x60/0x60
kernel: __do_sys_finit_module+0x94/0xe0
kernel: do_syscall_64+0x5a/0x270
kernel: entry_SYSCALL_64_after_hwframe+0x49/0xbe
process stack trace:
[<0>] __request_module+0x1c9/0x460
[<0>] ib_get_client_nl_info+0x5e/0xb0 [ib_core]
[<0>] nldev_get_chardev+0x1ac/0x320 [ib_core]
[<0>] rdma_nl_rcv_msg+0xeb/0x1d0 [ib_core]
[<0>] rdma_nl_rcv+0xcd/0x120 [ib_core]
[<0>] netlink_unicast+0x179/0x220
[<0>] netlink_sendmsg+0x2f6/0x3f0
[<0>] sock_sendmsg+0x30/0x40
[<0>] ___sys_sendmsg+0x27a/0x290
[<0>] __sys_sendmsg+0x58/0xa0
[<0>] do_syscall_64+0x5a/0x270
[<0>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
To overcome this deadlock and to allow multiple netlink messages to
progress in parallel, following scheme is implemented.
1. Split the lock protecting the cb_table into a per-index lock, and make
it a rwlock. This lock is used to ensure no callbacks are running after
unregistration returns. Since a module will not be registered once it
is already running callbacks, this avoids the deadlock.
2. Use smp_store_release() to update the cb_table during registration so
that no lock is required. This avoids lockdep problems with thinking
all the rwsems are the same lock class.
Fixes: 0e2d00eb6f ("RDMA: Add NLDEV_GET_CHARDEV to allow char dev discovery and autoload")
Link: https://lore.kernel.org/r/20191015080733.18625-1-leon@kernel.org
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Pull Devicetree fixes from Rob Herring:
"A couple more DT fixes for 5.4: fix a ref count, memory leak, and
Risc-V cpu schema warnings"
* tag 'devicetree-fixes-for-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
of: reserved_mem: add missing of_node_put() for proper ref-counting
of: unittest: fix memory leak in unittest_data_add
dt-bindings: riscv: Fix CPU schema errors
Taehee Yoo says:
====================
net: fix nested device bugs
This patchset fixes several bugs that are related to nesting
device infrastructure.
Current nesting infrastructure code doesn't limit the depth level of
devices. nested devices could be handled recursively. at that moment,
it needs huge memory and stack overflow could occur.
Below devices type have same bug.
VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, and VXLAN.
But I couldn't test all interface types so there could be more device
types, which have similar problems.
Maybe qmi_wwan.c code could have same problem.
So, I would appreciate if someone test qmi_wwan.c and other modules.
Test commands:
ip link add dummy0 type dummy
ip link add vlan1 link dummy0 type vlan id 1
for i in {2..100}
do
let A=$i-1
ip link add name vlan$i link vlan$A type vlan id $i
done
ip link del dummy0
1st patch actually fixes the root cause.
It adds new common variables {upper/lower}_level that represent
depth level. upper_level variable is depth of upper devices.
lower_level variable is depth of lower devices.
[U][L] [U][L]
vlan1 1 5 vlan4 1 4
vlan2 2 4 vlan5 2 3
vlan3 3 3 |
| |
+------------+
|
vlan6 4 2
dummy0 5 1
After this patch, the nesting infrastructure code uses this variable to
check the depth level.
2nd patch fixes Qdisc lockdep related problem.
Before this patch, devices use static lockdep map.
So, if devices that are same types are nested, lockdep will warn about
recursive situation.
These patches make these devices use dynamic lockdep key instead of
static lock or subclass.
3rd patch fixes unexpected IFF_BONDING bit unset.
When nested bonding interface scenario, bonding interface could lost it's
IFF_BONDING flag. This should not happen.
This patch adds a condition before unsetting IFF_BONDING.
4th patch fixes nested locking problem in bonding interface
Bonding interface has own lock and this uses static lock.
Bonding interface could be nested and it uses same lockdep key.
So that unexisting lockdep warning occurs.
5th patch fixes nested locking problem in team interface
Team interface has own lock and this uses static lock.
Team interface could be nested and it uses same lockdep key.
So that unexisting lockdep warning occurs.
6th patch fixes a refcnt leak in the macsec module.
When the macsec module is unloaded, refcnt leaks occur.
But actually, that holding refcnt is unnecessary.
So this patch just removes these code.
7th patch adds ignore flag to an adjacent structure.
In order to exchange an adjacent node safely, ignore flag is needed.
8th patch makes vxlan add an adjacent link to limit depth level.
Vxlan interface could set it's lower interface and these lower interfaces
are handled recursively.
So, if the depth of lower interfaces is too deep, stack overflow could
happen.
9th patch removes unnecessary variables and callback.
After 1st patch, subclass callback and variables are unnecessary.
This patch just removes these variables and callback.
10th patch fix refcnt leaks in the virt_wifi module
Like every nested interface, the upper interface should be deleted
before the lower interface is deleted.
In order to fix this, the notifier routine is added in this patch.
v4 -> v5 :
- Update log messages
- Move variables position, 1st patch
- Fix iterator routine, 1st patch
- Add generic lockdep key code, which replaces 2, 4, 5, 6, 7 patches.
- Log message update, 10th patch
- Fix wrong error value in error path of __init routine, 10th patch
- hold module refcnt when interface is created, 10th patch
v3 -> v4 :
- Add new 12th patch to fix refcnt leaks in the virt_wifi module
- Fix wrong usage netdev_upper_dev_link() in the vxlan.c
- Preserve reverse christmas tree variable ordering in the vxlan.c
- Add missing static keyword in the dev.c
- Expose netdev_adjacent_change_{prepare/commit/abort} instead of
netdev_adjacent_dev_{enable/disable}
v2 -> v3 :
- Modify nesting infrastructure code to use iterator instead of recursive.
v1 -> v2 :
- Make the 3rd patch do not add a new priv_flag.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes variables and callback these are related to the nested
device structure.
devices that can be nested have their own nest_level variable that
represents the depth of nested devices.
In the previous patch, new {lower/upper}_level variables are added and
they replace old private nest_level variable.
So, this patch removes all 'nest_level' variables.
In order to avoid lockdep warning, ->ndo_get_lock_subclass() was added
to get lockdep subclass value, which is actually lower nested depth value.
But now, they use the dynamic lockdep key to avoid lockdep warning instead
of the subclass.
So, this patch removes ->ndo_get_lock_subclass() callback.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to link an adjacent node, netdev_upper_dev_link() is used
and in order to unlink an adjacent node, netdev_upper_dev_unlink() is used.
unlink operation does not fail, but link operation can fail.
In order to exchange adjacent nodes, we should unlink an old adjacent
node first. then, link a new adjacent node.
If link operation is failed, we should link an old adjacent node again.
But this link operation can fail too.
It eventually breaks the adjacent link relationship.
This patch adds an ignore flag into the netdev_adjacent structure.
If this flag is set, netdev_upper_dev_link() ignores an old adjacent
node for a moment.
This patch also adds new functions for other modules.
netdev_adjacent_change_prepare()
netdev_adjacent_change_commit()
netdev_adjacent_change_abort()
netdev_adjacent_change_prepare() inserts new device into adjacent list
but new device is not allowed to use immediately.
If netdev_adjacent_change_prepare() fails, it internally rollbacks
adjacent list so that we don't need any other action.
netdev_adjacent_change_commit() deletes old device in the adjacent list
and allows new device to use.
netdev_adjacent_change_abort() rollbacks adjacent list.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a macsec interface is created, it increases a refcnt to a lower
device(real device). when macsec interface is deleted, the refcnt is
decreased in macsec_free_netdev(), which is ->priv_destructor() of
macsec interface.
The problem scenario is this.
When nested macsec interfaces are exiting, the exit routine of the
macsec module makes refcnt leaks.
Test commands:
ip link add dummy0 type dummy
ip link add macsec0 link dummy0 type macsec
ip link add macsec1 link macsec0 type macsec
modprobe -rv macsec
[ 208.629433] unregister_netdevice: waiting for macsec0 to become free. Usage count = 1
Steps of exit routine of macsec module are below.
1. Calls ->dellink() in __rtnl_link_unregister().
2. Checks refcnt and wait refcnt to be 0 if refcnt is not 0 in
netdev_run_todo().
3. Calls ->priv_destruvtor() in netdev_run_todo().
Step2 checks refcnt, but step3 decreases refcnt.
So, step2 waits forever.
This patch makes the macsec module do not hold a refcnt of the lower
device because it already holds a refcnt of the lower device with
netdev_upper_dev_link().
Fixes: c09440f7dc ("macsec: introduce IEEE 802.1AE driver")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
team interface could be nested and it's lock variable could be nested too.
But this lock uses static lockdep key and there is no nested locking
handling code such as mutex_lock_nested() and so on.
so the Lockdep would warn about the circular locking scenario that
couldn't happen.
In order to fix, this patch makes the team module to use dynamic lock key
instead of static key.
Test commands:
ip link add team0 type team
ip link add team1 type team
ip link set team0 master team1
ip link set team0 nomaster
ip link set team1 master team0
ip link set team1 nomaster
Splat that looks like:
[ 40.364352] WARNING: possible recursive locking detected
[ 40.364964] 5.4.0-rc3+ #96 Not tainted
[ 40.365405] --------------------------------------------
[ 40.365973] ip/750 is trying to acquire lock:
[ 40.366542] ffff888060b34c40 (&team->lock){+.+.}, at: team_set_mac_address+0x151/0x290 [team]
[ 40.367689]
but task is already holding lock:
[ 40.368729] ffff888051201c40 (&team->lock){+.+.}, at: team_del_slave+0x29/0x60 [team]
[ 40.370280]
other info that might help us debug this:
[ 40.371159] Possible unsafe locking scenario:
[ 40.371942] CPU0
[ 40.372338] ----
[ 40.372673] lock(&team->lock);
[ 40.373115] lock(&team->lock);
[ 40.373549]
*** DEADLOCK ***
[ 40.374432] May be due to missing lock nesting notation
[ 40.375338] 2 locks held by ip/750:
[ 40.375851] #0: ffffffffabcc42b0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0
[ 40.376927] #1: ffff888051201c40 (&team->lock){+.+.}, at: team_del_slave+0x29/0x60 [team]
[ 40.377989]
stack backtrace:
[ 40.378650] CPU: 0 PID: 750 Comm: ip Not tainted 5.4.0-rc3+ #96
[ 40.379368] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 40.380574] Call Trace:
[ 40.381208] dump_stack+0x7c/0xbb
[ 40.381959] __lock_acquire+0x269d/0x3de0
[ 40.382817] ? register_lock_class+0x14d0/0x14d0
[ 40.383784] ? check_chain_key+0x236/0x5d0
[ 40.384518] lock_acquire+0x164/0x3b0
[ 40.385074] ? team_set_mac_address+0x151/0x290 [team]
[ 40.385805] __mutex_lock+0x14d/0x14c0
[ 40.386371] ? team_set_mac_address+0x151/0x290 [team]
[ 40.387038] ? team_set_mac_address+0x151/0x290 [team]
[ 40.387632] ? mutex_lock_io_nested+0x1380/0x1380
[ 40.388245] ? team_del_slave+0x60/0x60 [team]
[ 40.388752] ? rcu_read_lock_sched_held+0x90/0xc0
[ 40.389304] ? rcu_read_lock_bh_held+0xa0/0xa0
[ 40.389819] ? lock_acquire+0x164/0x3b0
[ 40.390285] ? lockdep_rtnl_is_held+0x16/0x20
[ 40.390797] ? team_port_get_rtnl+0x90/0xe0 [team]
[ 40.391353] ? __module_text_address+0x13/0x140
[ 40.391886] ? team_set_mac_address+0x151/0x290 [team]
[ 40.392547] team_set_mac_address+0x151/0x290 [team]
[ 40.393111] dev_set_mac_address+0x1f0/0x3f0
[ ... ]
Fixes: 3d249d4ca7 ("net: introduce ethernet teaming device")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All bonding device has same lockdep key and subclass is initialized with
nest_level.
But actual nest_level value can be changed when a lower device is attached.
And at this moment, the subclass should be updated but it seems to be
unsafe.
So this patch makes bonding use dynamic lockdep key instead of the
subclass.
Test commands:
ip link add bond0 type bond
for i in {1..5}
do
let A=$i-1
ip link add bond$i type bond
ip link set bond$i master bond$A
done
ip link set bond5 master bond0
Splat looks like:
[ 307.992912] WARNING: possible recursive locking detected
[ 307.993656] 5.4.0-rc3+ #96 Tainted: G W
[ 307.994367] --------------------------------------------
[ 307.995092] ip/761 is trying to acquire lock:
[ 307.995710] ffff8880513aac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[ 307.997045]
but task is already holding lock:
[ 307.997923] ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[ 307.999215]
other info that might help us debug this:
[ 308.000251] Possible unsafe locking scenario:
[ 308.001137] CPU0
[ 308.001533] ----
[ 308.001915] lock(&(&bond->stats_lock)->rlock#2/2);
[ 308.002609] lock(&(&bond->stats_lock)->rlock#2/2);
[ 308.003302]
*** DEADLOCK ***
[ 308.004310] May be due to missing lock nesting notation
[ 308.005319] 3 locks held by ip/761:
[ 308.005830] #0: ffffffff9fcc42b0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0
[ 308.006894] #1: ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[ 308.008243] #2: ffffffff9f9219c0 (rcu_read_lock){....}, at: bond_get_stats+0x9f/0x500 [bonding]
[ 308.009422]
stack backtrace:
[ 308.010124] CPU: 0 PID: 761 Comm: ip Tainted: G W 5.4.0-rc3+ #96
[ 308.011097] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 308.012179] Call Trace:
[ 308.012601] dump_stack+0x7c/0xbb
[ 308.013089] __lock_acquire+0x269d/0x3de0
[ 308.013669] ? register_lock_class+0x14d0/0x14d0
[ 308.014318] lock_acquire+0x164/0x3b0
[ 308.014858] ? bond_get_stats+0xb8/0x500 [bonding]
[ 308.015520] _raw_spin_lock_nested+0x2e/0x60
[ 308.016129] ? bond_get_stats+0xb8/0x500 [bonding]
[ 308.017215] bond_get_stats+0xb8/0x500 [bonding]
[ 308.018454] ? bond_arp_rcv+0xf10/0xf10 [bonding]
[ 308.019710] ? rcu_read_lock_held+0x90/0xa0
[ 308.020605] ? rcu_read_lock_sched_held+0xc0/0xc0
[ 308.021286] ? bond_get_stats+0x9f/0x500 [bonding]
[ 308.021953] dev_get_stats+0x1ec/0x270
[ 308.022508] bond_get_stats+0x1d1/0x500 [bonding]
Fixes: d3fff6c443 ("net: add netdev_lockdep_set_classes() helper")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some interface types could be nested.
(VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, VIRT_WIFI, VXLAN, etc..)
These interface types should set lockdep class because, without lockdep
class key, lockdep always warn about unexisting circular locking.
In the current code, these interfaces have their own lockdep class keys and
these manage itself. So that there are so many duplicate code around the
/driver/net and /net/.
This patch adds new generic lockdep keys and some helper functions for it.
This patch does below changes.
a) Add lockdep class keys in struct net_device
- qdisc_running, xmit, addr_list, qdisc_busylock
- these keys are used as dynamic lockdep key.
b) When net_device is being allocated, lockdep keys are registered.
- alloc_netdev_mqs()
c) When net_device is being free'd llockdep keys are unregistered.
- free_netdev()
d) Add generic lockdep key helper function
- netdev_register_lockdep_key()
- netdev_unregister_lockdep_key()
- netdev_update_lockdep_key()
e) Remove unnecessary generic lockdep macro and functions
f) Remove unnecessary lockdep code of each interfaces.
After this patch, each interface modules don't need to maintain
their lockdep keys.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current code doesn't limit the number of nested devices.
Nested devices would be handled recursively and this needs huge stack
memory. So, unlimited nested devices could make stack overflow.
This patch adds upper_level and lower_level, they are common variables
and represent maximum lower/upper depth.
When upper/lower device is attached or dettached,
{lower/upper}_level are updated. and if maximum depth is bigger than 8,
attach routine fails and returns -EMLINK.
In addition, this patch converts recursive routine of
netdev_walk_all_{lower/upper} to iterator routine.
Test commands:
ip link add dummy0 type dummy
ip link add link dummy0 name vlan1 type vlan id 1
ip link set vlan1 up
for i in {2..55}
do
let A=$i-1
ip link add vlan$i link vlan$A type vlan id $i
done
ip link del dummy0
Splat looks like:
[ 155.513226][ T908] BUG: KASAN: use-after-free in __unwind_start+0x71/0x850
[ 155.514162][ T908] Write of size 88 at addr ffff8880608a6cc0 by task ip/908
[ 155.515048][ T908]
[ 155.515333][ T908] CPU: 0 PID: 908 Comm: ip Not tainted 5.4.0-rc3+ #96
[ 155.516147][ T908] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 155.517233][ T908] Call Trace:
[ 155.517627][ T908]
[ 155.517918][ T908] Allocated by task 0:
[ 155.518412][ T908] (stack is not available)
[ 155.518955][ T908]
[ 155.519228][ T908] Freed by task 0:
[ 155.519885][ T908] (stack is not available)
[ 155.520452][ T908]
[ 155.520729][ T908] The buggy address belongs to the object at ffff8880608a6ac0
[ 155.520729][ T908] which belongs to the cache names_cache of size 4096
[ 155.522387][ T908] The buggy address is located 512 bytes inside of
[ 155.522387][ T908] 4096-byte region [ffff8880608a6ac0, ffff8880608a7ac0)
[ 155.523920][ T908] The buggy address belongs to the page:
[ 155.524552][ T908] page:ffffea0001822800 refcount:1 mapcount:0 mapping:ffff88806c657cc0 index:0x0 compound_mapcount:0
[ 155.525836][ T908] flags: 0x100000000010200(slab|head)
[ 155.526445][ T908] raw: 0100000000010200 ffffea0001813808 ffffea0001a26c08 ffff88806c657cc0
[ 155.527424][ T908] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[ 155.528429][ T908] page dumped because: kasan: bad access detected
[ 155.529158][ T908]
[ 155.529410][ T908] Memory state around the buggy address:
[ 155.530060][ T908] ffff8880608a6b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 155.530971][ T908] ffff8880608a6c00: fb fb fb fb fb f1 f1 f1 f1 00 f2 f2 f2 f3 f3 f3
[ 155.531889][ T908] >ffff8880608a6c80: f3 fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 155.532806][ T908] ^
[ 155.533509][ T908] ffff8880608a6d00: fb fb fb fb fb fb fb fb fb f1 f1 f1 f1 00 00 00
[ 155.534436][ T908] ffff8880608a6d80: f2 f3 f3 f3 f3 fb fb fb 00 00 00 00 00 00 00 00
[ ... ]
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull ACPI fix from Rafael Wysocki:
"Fix locking issue in the error code path of a function that belongs to
the sysfs interface exposed by the ACPI NFIT handling code (Dan
Carpenter)"
* tag 'acpi-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: NFIT: Fix unlock on error in scrub_show()
