[ Upstream commit 63c3194b82 ]
The RESET register only have one self clearing bit and it should not be
cached. If it is cached, when we sync the registers back to the chip we
will initiate a software reset as well, which is not desirable.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2f884e6e68 ]
The below call chain generates "scheduling while atomic" backtrace and
causes system crash when Keystone 2 IRQ chip driver is used with RT-kernel:
gic_handle_irq()
|-__handle_domain_irq()
|-generic_handle_irq()
|-keystone_irq_handler()
|-regmap_read()
|-regmap_lock_spinlock()
|-rt_spin_lock()
The reason is that Keystone driver dispatches IRQ using chained IRQ handler
and accesses I/O memory through syscon->regmap(mmio) which is implemented
as fast_io regmap and uses regular spinlocks for synchronization, but
spinlocks transformed to rt_mutexes on RT.
Hence, convert Keystone 2 IRQ driver to use generic irq handler instead of
chained IRQ handler. This way it will be compatible with RT kernel where it
will be forced thread IRQ handler while in non-RT kernel it still will be
executed in HW IRQ context.
Cc: Suman Anna <s-anna@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Suman Anna <s-anna@ti.com>
Link: https://lkml.kernel.org/r/20161208233310.10329-1-grygorii.strashko@ti.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 45e8697144 ]
Using ancient compilers (gcc-4.5 or older) on ARM, we get a link
failure with the vfio-pci driver:
ERROR: "__aeabi_lcmp" [drivers/vfio/pci/vfio-pci.ko] undefined!
The reason is that the compiler tries to do a comparison of
a 64-bit range. This changes it to convert to a 32-bit number
explicitly first, as newer compilers do for themselves.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a6cb3b864b ]
For every submission buffer object one of MSM_SUBMIT_BO_WRITE
and MSM_SUBMIT_BO_READ must be set (and nothing else). If we
allowed zero then the buffer object would never get queued to
be unreferenced.
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 88b333b0ed ]
Currently the value written to CP_RB_WPTR is calculated on the fly as
(rb->next - rb->start). But as the code is designed rb->next is wrapped
before writing the commands so if a series of commands happened to
fit perfectly in the ringbuffer, rb->next would end up being equal to
rb->size / 4 and thus result in an out of bounds address to CP_RB_WPTR.
The easiest way to fix this is to mask WPTR when writing it to the
hardware; it makes the hardware happy and the rest of the ringbuffer
math appears to work and there isn't any point in upsetting anything.
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
[squash in is_power_of_2() check]
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 10b1c04e92 ]
Demoting simple flow steering rule priority (for DPDK) was achieved by
wrapping FW commands MLX4_QP_FLOW_STEERING_ATTACH/DETACH for the PF
as well, and forcing the priority to MLX4_DOMAIN_NIC in the wrapper
function for the PF and all VFs.
In function mlx4_ib_create_flow(), this change caused the main rule
creation for the PF to be wrapped, while it left the associated
tunnel steering rule creation unwrapped for the PF.
This mismatch caused rule deletion failures in mlx4_ib_destroy_flow()
for the PF when the detach wrapper function did not find the associated
tunnel-steering rule (since creation of that rule for the PF did not
go through the wrapper function).
Fix this by setting MLX4_QP_FLOW_STEERING_ATTACH/DETACH to be "native"
(so that the PF invocation does not go through the wrapper), and perform
the required priority demotion for the PF in the mlx4_ib_create_flow()
code path.
Fixes: 48564135cb ("net/mlx4_core: Demote simple multicast and broadcast flow steering rules")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.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>
[ Upstream commit 3b01fe7f91 ]
mlx4_QP_FLOW_STEERING_DETACH_wrapper first removes the steering
rule (which results in freeing the rule structure), and then
references a field in this struct (the qp number) when releasing the
busy-status on the rule's qp.
Since this memory was freed, it could reallocated and changed.
Therefore, the qp number in the struct may be incorrect,
so that we are releasing the incorrect qp. This leaves the rule's qp
in the busy state (and could possibly release an incorrect qp as well).
Fix this by saving the qp number in a local variable, for use after
removing the steering rule.
Fixes: 2c473ae7e5 ("net/mlx4_core: Disallow releasing VF QPs which have steering rules")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.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>
[ Upstream commit e4c5e13aa4 ]
There is an inconsistent conditional judgement between __ip6_append_data
and ip6_finish_output functions, the variable length in __ip6_append_data
just include the length of application's payload and udp6 header, don't
include the length of ipv6 header, but in ip6_finish_output use
(skb->len > ip6_skb_dst_mtu(skb)) as judgement, and skb->len include the
length of ipv6 header.
That causes some particular application's udp6 payloads whose length are
between (MTU - IPv6 Header) and MTU were fragmented by ip6_fragment even
though the rst->dev support UFO feature.
Add the length of ipv6 header to length in __ip6_append_data to keep
consistent conditional judgement as ip6_finish_output for ip6 fragment.
Signed-off-by: Zheng Li <james.z.li@ericsson.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>
[ Upstream commit 9da34cd34e ]
Under the switchdev/offloads mode, packets that don't match any
e-switch steering rule are sent towards the e-switch management
port. We use a NIC HW steering rule set per vport (uplink and VFs)
to make them be received into the host OS through the respective
vport representor netdevice.
Currnetly such missed RoCE packets will not get to this NIC steering
rule, and hence VF RoCE will not work over the slow path of the offloads
mode. This is b/c these packets will be matched by a steering rule added
by the firmware that serves RoCE traffic set on the PF NIC vport which
is also the e-switch management port under SRIOV.
Disabling RoCE on the e-switch management vport when we are in the offloads
mode, will signal to the firmware to remove their RoCE rule, and then the
missed RoCE packets will be matched by the representor NIC steering rule
as any other missed packets.
To achieve that, we disable RoCE on the PF vport. We do that by removing
(hot-unplugging) the IB device instance associated with the PF. This is
also required by our current model where the PF serves as the uplink
representor and hence only SW switching (TC, bridge, OVS) applications
and slow path vport mlx5e net-device should be running over that vport.
Fixes: c930a3ad74 ('net/mlx5e: Add devlink based SRIOV mode changes')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.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>
[ Upstream commit 4cf48f1d75 ]
Trying to initialize eMMC slot as SDIO or SD cause failure in n900 port of
qemu. eMMC itself is not detected and is not working.
Real Nokia N900 harware does not have this problem. As eMMC is really not
SDIO or SD based such change is harmless and will fix support for qemu.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5acd016c88 ]
USB2 port can be operated in dual-role mode but till we
have dual-role support in dwc3 driver let's limit this
port to peripheral mode.
If we don't do so it defaults to host mode. USB1 port
is meant for host only operation and we don't want
both ports in host only mode.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bbb3be170a upstream.
Fix warnings of the form...
WARNING: CPU: 10 PID: 4983 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80
sysfs: cannot create duplicate filename '/class/dax/dax12.0'
Call Trace:
dump_stack+0x63/0x86
__warn+0xcb/0xf0
warn_slowpath_fmt+0x5a/0x80
? kernfs_path_from_node+0x4f/0x60
sysfs_warn_dup+0x62/0x80
sysfs_do_create_link_sd.isra.2+0x97/0xb0
sysfs_create_link+0x25/0x40
device_add+0x266/0x630
devm_create_dax_dev+0x2cf/0x340 [dax]
dax_pmem_probe+0x1f5/0x26e [dax_pmem]
nvdimm_bus_probe+0x71/0x120
...by reusing the namespace id for the device-dax instance name.
Now that we have decided that there will never by more than one
device-dax instance per libnvdimm-namespace parent device [1], we can
directly reuse the namepace ids. There are some possible follow-on
cleanups, but those are saved for a later patch to simplify the -stable
backport.
[1]: https://lists.01.org/pipermail/linux-nvdimm/2016-December/008266.html
Fixes: 98a29c39dc ("libnvdimm, namespace: allow creation of multiple pmem...")
Cc: Jeff Moyer <jmoyer@redhat.com>
Reported-by: Dariusz Dokupil <dariusz.dokupil@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e7bc478c9 upstream.
My recent change missed fact that UFO would perform a complete
UDP checksum before segmenting in frags.
In this case skb->ip_summed is set to CHECKSUM_NONE.
We need to add this valid case to skb_needs_check()
Fixes: b2504a5dbe ("net: reduce skb_warn_bad_offload() noise")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e9a330c428 upstream.
The per-prz spinlock should be using the dynamic initializer so that
lockdep can correctly track it. Without this, under lockdep, we get a
warning at boot that the lock is in non-static memory.
Fixes: 109704492e ("pstore: Make spinlock per zone instead of global")
Fixes: 76d5692a58 ("pstore: Correctly initialize spinlock and flags")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 663deb4788 upstream.
In preparation of not locking at all for certain buffers depending on if
there's contention, make locking optional depending on the initialization
of the prz.
Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: moved locking flag into prz instead of via caller arguments]
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 49d31c2f38 upstream.
take_dentry_name_snapshot() takes a safe snapshot of dentry name;
if the name is a short one, it gets copied into caller-supplied
structure, otherwise an extra reference to external name is grabbed
(those are never modified). In either case the pointer to stable
string is stored into the same structure.
dentry must be held by the caller of take_dentry_name_snapshot(),
but may be freely dropped afterwards - the snapshot will stay
until destroyed by release_dentry_name_snapshot().
Intended use:
struct name_snapshot s;
take_dentry_name_snapshot(&s, dentry);
...
access s.name
...
release_dentry_name_snapshot(&s);
Replaces fsnotify_oldname_...(), gets used in fsnotify to obtain the name
to pass down with event.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 860f01e969 upstream.
systemd by default starts watchdog on reboot and sets the timer to
ShutdownWatchdogSec=10min. Reboot handler in ipmi_watchdog than reduces
the timer to 120s which is not enough time to boot a Xen machine with
a lot of RAM. As a result the machine is rebooted the second time
during the long run of (XEN) Scrubbing Free RAM.....
Fix this by setting the timer to 120s only if it was previously
set to a low value.
Signed-off-by: Valentin Vidic <Valentin.Vidic@CARNet.hr>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5a7a88f1b4 upstream.
The port number is only valid if IB_QP_PORT is set in the mask.
So only check port number if it is valid to prevent modify_qp from
failing due to an invalid port number.
Fixes: 5ecce4c9b17b("Check port number supplied by user verbs cmds")
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 96b777452d upstream.
Commit:
2f5177f0fd ("sched/cgroup: Fix/cleanup cgroup teardown/init")
.. moved sched_online_group() from css_online() to css_alloc().
It exposes half-baked task group into global lists before initializing
generic cgroup stuff.
LTP testcase (third in cgroup_regression_test) written for testing
similar race in kernels 2.6.26-2.6.28 easily triggers this oops:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: kernfs_path_from_node_locked+0x260/0x320
CPU: 1 PID: 30346 Comm: cat Not tainted 4.10.0-rc5-test #4
Call Trace:
? kernfs_path_from_node+0x4f/0x60
kernfs_path_from_node+0x3e/0x60
print_rt_rq+0x44/0x2b0
print_rt_stats+0x7a/0xd0
print_cpu+0x2fc/0xe80
? __might_sleep+0x4a/0x80
sched_debug_show+0x17/0x30
seq_read+0xf2/0x3b0
proc_reg_read+0x42/0x70
__vfs_read+0x28/0x130
? security_file_permission+0x9b/0xc0
? rw_verify_area+0x4e/0xb0
vfs_read+0xa5/0x170
SyS_read+0x46/0xa0
entry_SYSCALL_64_fastpath+0x1e/0xad
Here the task group is already linked into the global RCU-protected 'task_groups'
list, but the css->cgroup pointer is still NULL.
This patch reverts this chunk and moves online back to css_online().
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 2f5177f0fd ("sched/cgroup: Fix/cleanup cgroup teardown/init")
Link: http://lkml.kernel.org/r/148655324740.424917.5302984537258726349.stgit@buzz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cb710ab1d8 upstream.
We already check if the message is empty before calling the client
tx_done callback. Calling completion on a wait event is also invalid
if the message is empty.
This patch moves the existing empty message check earlier.
Fixes: 2b6d83e2b8 ("mailbox: Introduce framework for mailbox")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cc6eeaa302 upstream.
If a wait_for_completion_timeout() call returns due to a timeout,
complete() can get called after returning from the wait which is
incorrect and can cause subsequent transmissions on a channel to fail.
Since the wait_for_completion_timeout() sees the completion variable
is non-zero caused by the erroneous/spurious complete() call, and
it immediately returns without waiting for the time as expected by the
client.
This patch fixes the issue by skipping complete() call for the timer
expiry.
Fixes: 2b6d83e2b8 ("mailbox: Introduce framework for mailbox")
Reported-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c61b781ee0 upstream.
There exists a race when msg_submit return immediately as there was an
active request being processed which may have completed just before it's
checked again in mbox_send_message. This will result in return to the
caller without waiting in mbox_send_message even when it's blocking Tx.
This patch fixes the issue by waiting for the completion always if Tx
is in blocking mode.
Fixes: 2b6d83e2b8 ("mailbox: Introduce framework for mailbox")
Reported-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e8f4ae8543 upstream.
The driver may sleep under a spin lock, the function call path is:
isdn_ppp_mp_receive (acquire the lock)
isdn_ppp_mp_reassembly
isdn_ppp_push_higher
isdn_ppp_decompress
isdn_ppp_ccp_reset_trans
isdn_ppp_ccp_reset_alloc_state
kzalloc(GFP_KERNEL) --> may sleep
To fixed it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC".
Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0878fff1f4 upstream.
The Generic PHY driver is a catch-all PHY driver and it should preserve
whatever prior initialization has been done by boot loader or firmware
agents. For specific PHY device configuration it is expected that a
specialized PHY driver would take over that role.
Resetting the generic PHY was a bad idea that has lead to several
complaints and downstream workarounds e.g: in OpenWrt/LEDE so restore
the behavior prior to 87aa9f9c61 ("net: phy: consolidate PHY
reset in phy_init_hw()").
Reported-by: Felix Fietkau <nbd@nbd.name>
Fixes: 87aa9f9c61 ("net: phy: consolidate PHY reset in phy_init_hw()")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b6355fb3f5 upstream.
We are checking phy after dereferencing it. We can print the debug
information after checking it. If phy is NULL then we will get a good
stack trace to tell us that we are in this irq handler.
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2497128133 upstream.
If port100_send_ack() was called twice or more, it has race to hangup.
port100_send_ack() port100_send_ack()
init_completion()
[...]
dev->cmd_cancel = true
/* this removes previous from completion */
init_completion()
[...]
dev->cmd_cancel = true
wait_for_completion()
/* never be waked up */
wait_for_completion()
Like above race, this code is not assuming port100_send_ack() is
called twice or more.
To fix, this checks dev->cmd_cancel to know if prior cancel is
in-flight or not. And never be remove prior task from completion by
using reinit_completion(), so this guarantees to be waked up properly
soon or later.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dea1d0f5f1 upstream.
The move of the unpark functions to the control thread moved the BUG_ON()
there as well. While it made some sense in the idle thread of the upcoming
CPU, it's bogus to crash the control thread on the already online CPU,
especially as the function has a return value and the callsite is prepared
to handle an error return.
Replace it with a WARN_ON_ONCE() and return a proper error code.
Fixes: 9cd4f1a4e7 ("smp/hotplug: Move unparking of percpu threads to the control CPU")
Rightfully-ranted-at-by: Linux Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9cd4f1a4e7 upstream.
Vikram reported the following backtrace:
BUG: scheduling while atomic: swapper/7/0/0x00000002
CPU: 7 PID: 0 Comm: swapper/7 Not tainted 4.9.32-perf+ #680
schedule
schedule_hrtimeout_range_clock
schedule_hrtimeout
wait_task_inactive
__kthread_bind_mask
__kthread_bind
__kthread_unpark
kthread_unpark
cpuhp_online_idle
cpu_startup_entry
secondary_start_kernel
He analyzed correctly that a parked cpu hotplug thread of an offlined CPU
was still on the runqueue when the CPU came back online and tried to unpark
it. This causes the thread which invoked kthread_unpark() to call
wait_task_inactive() and subsequently schedule() with preemption disabled.
His proposed workaround was to "make sure" that a parked thread has
scheduled out when the CPU goes offline, so the situation cannot happen.
But that's still wrong because the root cause is not the fact that the
percpu thread is still on the runqueue and neither that preemption is
disabled, which could be simply solved by enabling preemption before
calling kthread_unpark().
The real issue is that the calling thread is the idle task of the upcoming
CPU, which is not supposed to call anything which might sleep. The moron,
who wrote that code, missed completely that kthread_unpark() might end up
in schedule().
The solution is simpler than expected. The thread which controls the
hotplug operation is waiting for the CPU to call complete() on the hotplug
state completion. So the idle task of the upcoming CPU can set its state to
CPUHP_AP_ONLINE_IDLE and invoke complete(). This in turn wakes the control
task on a different CPU, which then can safely do the unpark and kick the
now unparked hotplug thread of the upcoming CPU to complete the bringup to
the final target state.
Control CPU AP
bringup_cpu();
__cpu_up() ------------>
bringup_ap();
bringup_wait_for_ap()
wait_for_completion();
cpuhp_online_idle();
<------------ complete();
unpark(AP->stopper);
unpark(AP->hotplugthread);
while(1)
do_idle();
kick(AP->hotplugthread);
wait_for_completion(); hotplug_thread()
run_online_callbacks();
complete();
Fixes: 8df3e07e7f ("cpu/hotplug: Let upcoming cpu bring itself fully up")
Reported-by: Vikram Mulukutla <markivx@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Sewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1707042218020.2131@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4f7b0d2638 upstream.
It isn't safe to call drm_dev_unregister() without first initializing
mode setting with drm_mode_config_init(). This leads to a crash if
either IO memory can't be remapped or vblank initialization fails.
Fix this by reordering the initialization sequence. Move vblank
initialization after the drm_mode_config_init() call, and move IO
remapping before drm_dev_alloc() to avoid the need to perform clean up
in case of failure.
While at it remove the explicit drm_vblank_cleanup() call from
rcar_du_remove() as the drm_dev_unregister() function already cleans up
vblank.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: thongsyho <thong.ho.px@rvc.renesas.com>
Signed-off-by: Nhan Nguyen <nhan.nguyen.yb@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit b4624ff952 which is
commit ba4a648f12 upstream.
Michal Hocko writes:
JFYI. We have encountered a regression after applying this patch on a
large ppc machine. While the patch is the right thing to do it doesn't
work well with the current vmalloc area size on ppc and large machines
where NUMA nodes are very far from each other. Just for the reference
the boot fails on such a machine with bunch of warning preceeding it.
See http://lkml.kernel.org/r/20170724134240.GL25221@dhcp22.suse.cz
It seems the right thing to do is to enlarge the vmalloc space on ppc
but this is not the case in the upstream kernel yet AFAIK. It is also
questionable whether that is a stable material but I will decision on
you here.
We have reverted this patch from our 4.4 based kernel.
Newer kernels do not have enlarged vmalloc space yet AFAIK so they won't
work properly eiter. This bug is quite rare though because you need a
specific HW configuration to trigger the issue - namely NUMA nodes have
to be far away from each other in the physical memory space.
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7ceaa6dcd8 upstream.
At present, HV KVM on POWER8 and POWER9 machines loses any instruction
or data breakpoint set in the host whenever a guest is run.
Instruction breakpoints are currently only used by xmon, but ptrace
and the perf_event subsystem can set data breakpoints as well as xmon.
To fix this, we save the host values of the debug registers (CIABR,
DAWR and DAWRX) before entering the guest and restore them on exit.
To provide space to save them in the stack frame, we expand the stack
frame allocated by kvmppc_hv_entry() from 112 to 144 bytes.
[paulus@ozlabs.org - Adjusted stack offsets since we aren't saving
POWER9-specific registers.]
Fixes: b005255e12 ("KVM: PPC: Book3S HV: Context-switch new POWER8 SPRs", 2014-01-08)
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4c3bb4ccd0 upstream.
This restores several special-purpose registers (SPRs) to sane values
on guest exit that were missed before.
TAR and VRSAVE are readable and writable by userspace, and we need to
save and restore them to prevent the guest from potentially affecting
userspace execution (not that TAR or VRSAVE are used by any known
program that run uses the KVM_RUN ioctl). We save/restore these
in kvmppc_vcpu_run_hv() rather than on every guest entry/exit.
FSCR affects userspace execution in that it can prohibit access to
certain facilities by userspace. We restore it to the normal value
for the task on exit from the KVM_RUN ioctl.
IAMR is normally 0, and is restored to 0 on guest exit. However,
with a radix host on POWER9, it is set to a value that prevents the
kernel from executing user-accessible memory. On POWER9, we save
IAMR on guest entry and restore it on guest exit to the saved value
rather than 0. On POWER8 we continue to set it to 0 on guest exit.
PSPB is normally 0. We restore it to 0 on guest exit to prevent
userspace taking advantage of the guest having set it non-zero
(which would allow userspace to set its SMT priority to high).
UAMOR is normally 0. We restore it to 0 on guest exit to prevent
the AMR from being used as a covert channel between userspace
processes, since the AMR is not context-switched at present.
[paulus@ozlabs.org - removed IAMR bits that are only needed on POWER9]
Fixes: b005255e12 ("KVM: PPC: Book3S HV: Context-switch new POWER8 SPRs", 2014-01-08)
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 38bcb208f6 upstream.
Bit 30 being set causes the upper half of BAR2 to stay in physical mode,
mapped over the end of VRAM, even when the rest of the BAR has been set
to virtual mode.
We inherited our initial value from RM, but I'm not aware of any reason
we need to keep it that way.
This fixes severe GPU hang/lockup issues revealed by Wayland on F26.
Shout-out to NVIDIA for the quick response with the potential cause!
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a90e049cac upstream.
GP102's cursors go from chan 17..20. Increase the array size to hold
their data properly.
Fixes: e50fcff15f ("drm/nouveau/disp/gp102: fix cursor/overlay immediate channel indices")
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
