When it failed to write probe commands to the probe_event file in
debugfs, it needs to propagate the error code properly. Current code
blindly uses the return value of the write(2) so it always uses
-1 (-EPERM) and it might confuse users.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1420886028-15135-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A worker_pool's forward progress is guaranteed by the fact that the
last idle worker assumes the manager role to create more workers and
summon the rescuers if creating workers doesn't succeed in timely
manner before proceeding to execute work items.
This manager role is implemented in manage_workers(), which indicates
whether the worker may proceed to work item execution with its return
value. This is necessary because multiple workers may contend for the
manager role, and, if there already is a manager, others should
proceed to work item execution.
Unfortunately, the function also indicates that the worker may proceed
to work item execution if need_to_create_worker() is false at the head
of the function. need_to_create_worker() tests the following
conditions.
pending work items && !nr_running && !nr_idle
The first and third conditions are protected by pool->lock and thus
won't change while holding pool->lock; however, nr_running can change
asynchronously as other workers block and resume and while it's likely
to be zero, as someone woke this worker up in the first place, some
other workers could have become runnable inbetween making it non-zero.
If this happens, manage_worker() could return false even with zero
nr_idle making the worker, the last idle one, proceed to execute work
items. If then all workers of the pool end up blocking on a resource
which can only be released by a work item which is pending on that
pool, the whole pool can deadlock as there's no one to create more
workers or summon the rescuers.
This patch fixes the problem by removing the early exit condition from
maybe_create_worker() and making manage_workers() return false iff
there's already another manager, which ensures that the last worker
doesn't start executing work items.
We can leave the early exit condition alone and just ignore the return
value but the only reason it was put there is because the
manage_workers() used to perform both creations and destructions of
workers and thus the function may be invoked while the pool is trying
to reduce the number of workers. Now that manage_workers() is called
only when more workers are needed, the only case this early exit
condition is triggered is rare race conditions rendering it pointless.
Tested with simulated workload and modified workqueue code which
trigger the pool deadlock reliably without this patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Eric Sandeen <sandeen@sandeen.net>
Link: http://lkml.kernel.org/g/54B019F4.8030009@sandeen.net
Cc: Dave Chinner <david@fromorbit.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: stable@vger.kernel.org
Here are 3 small driver fixes for reported issues for 3.19-rc5. All of
these have been in linux-next for a while with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are three small driver fixes for reported issues for 3.19-rc5.
All of these have been in linux-next for a while with no reported
problems"
* tag 'char-misc-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
mcb: mcb-pci: Only remap the 1st 0x200 bytes of BAR 0
mei: add ABI documentation for fw_status exported through sysfs
mei: clean reset bit before reset
Here is one kernfs fix for a reported issue for 3.19-rc5.
It has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fix from Greg KH:
"Here is one kernfs fix for a reported issue for 3.19-rc5.
It has been in linux-next for a while"
* tag 'driver-core-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
kernfs: Fix kernfs_name_compare
Here are some tty and serial driver fixes for 3.19-rc5 that resolve some
reported issues, and add a new device id to the 8250 serial port driver.
All have been in linux-next with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver fixes from Greg KH:
"Here are some tty and serial driver fixes for 3.19-rc5 that resolve
some reported issues, and add a new device id to the 8250 serial port
driver.
All have been in linux-next with no reported problems"
* tag 'tty-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: samsung: Add the support for Exynos5433 SoC
Revert "tty: Fix pty master poll() after slave closes v2"
tty: Prevent hw state corruption in exclusive mode reopen
tty: Add support for the WCH384 4S multi-IO card
serial: fix parisc boot hang
Here are 6 staging driver fixes for 3.19-rc5.
They fix some reported issues with some IIO drivers, as well as some
issues with the vt6655 wireless driver.
All have been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver fixes from Greg KH:
"Here are 6 staging driver fixes for 3.19-rc5.
They fix some reported issues with some IIO drivers, as well as some
issues with the vt6655 wireless driver.
All have been in linux-next for a while"
* tag 'staging-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: vt6655: fix sparse warning: argument type
staging: vt6655: Fix loss of distant/weak access points on channel change.
staging: vt6655: vnt_tx_packet Fix corrupted tx packets.
staging: vt6655: fix sparse warnings: incorrect argument type
iio: iio: Fix iio_channel_read return if channel havn't info
iio: ad799x: Fix ad7991/ad7995/ad7999 config setup
Here is a bunch of USB fixes for 3.19-rc5.
Most of these are gadget driver fixes, along with the xhci driver fix
that we both reported having problems with, as well as some new device
ids and other tiny fixes.
All have been in linux-next with no problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here is a bunch of USB fixes for 3.19-rc5.
Most of these are gadget driver fixes, along with the xhci driver fix
that we both reported having problems with, as well as some new device
ids and other tiny fixes.
All have been in linux-next with no problems"
* tag 'usb-3.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (43 commits)
usb: dwc3: gadget: Stop TRB preparation after limit is reached
usb: dwc3: gadget: Fix TRB preparation during SG
usb: phy: mv-usb: fix usb_phy build errors
usb: serial: handle -ENODEV quietly in generic_submit_read_urb
usb: serial: silence all non-critical read errors
USB: console: fix potential use after free
USB: console: fix uninitialised ldisc semaphore
usb: gadget: udc: atmel: fix possible oops when unloading module
usb: gadget: gadgetfs: fix an oops in ep_write()
usb: phy: Fix deferred probing
OHCI: add a quirk for ULi M5237 blocking on reset
uas: Add US_FL_NO_ATA_1X for 2 more Seagate disk enclosures
uas: Do not blacklist ASM1153 disk enclosures
usb: gadget: udc: avoid dereference before NULL check in ep_queue
usb: host: ehci-tegra: request deferred probe when failing to get phy
uas: disable UAS on Apricorn SATA dongles
uas: Add US_FL_NO_REPORT_OPCODES for JMicron JMS566 with usb-id 0bc2:a013
uas: Add US_FL_NO_ATA_1X for Seagate devices with usb-id 0bc2:a013
xhci: Add broken-streams quirk for Fresco Logic FL1000G xhci controllers
USB: EHCI: adjust error return code
...
- Wire up compat_sys_execveat for compat (AArch32) tasks
- Revert 421520ba98, as this breaks our side of the boot protocol
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
- Wire up compat_sys_execveat for compat (AArch32) tasks
- Revert 421520ba98, as this breaks our side of the boot protocol
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: partially revert "ARM: 8167/1: extend the reserved memory for initrd to be page aligned"
arm64: compat: wire up compat_sys_execveat
Highlights include:
- Stable fix for a NFSv3/lockd race
- Fixes for several NFSv4.1 client id trunking bugs
- Remove an incorrect test when checking for delegated opens
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Merge tag 'nfs-for-3.19-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Stable fix for a NFSv3/lockd race
- Fixes for several NFSv4.1 client id trunking bugs
- Remove an incorrect test when checking for delegated opens"
* tag 'nfs-for-3.19-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Remove incorrect check in can_open_delegated()
NFS: Ignore transport protocol when detecting server trunking
NFSv4/v4.1: Verify the client owner id during trunking detection
NFSv4: Cache the NFSv4/v4.1 client owner_id in the struct nfs_client
NFSv4.1: Fix client id trunking on Linux
LOCKD: Fix a race when initialising nlmsvc_timeout
the mixture of function graph tracing and kprobes.
When jprobes and function graph tracing is enabled at the same time
it will crash the system.
# modprobe jprobe_example
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
After the first fork (jprobe_example probes it), the system will crash.
This is due to the way jprobes copies the stack frame and does not
do a normal function return. This messes up with the function graph
tracing accounting which hijacks the return address from the stack
and replaces it with a hook function. It saves the return addresses in
a separate stack to put back the correct return address when done.
But because the jprobe functions do not do a normal return, their
stack addresses are not put back until the function they probe is called,
which means that the probed function will get the return address of
the jprobe handler instead of its own.
The simple fix here was to disable function graph tracing while the
jprobe handler is being called.
While debugging this I found two minor bugs with the function graph
tracing.
The first was about the function graph tracer sharing its function hash
with the function tracer (they both get filtered by the same input).
The changing of the set_ftrace_filter would not sync the function recording
records after a change if the function tracer was disabled but the
function graph tracer was enabled. This was due to the update only checking
one of the ops instead of the shared ops to see if they were enabled and
should perform the sync. This caused the ftrace accounting to break and
a ftrace_bug() would be triggered, disabling ftrace until a reboot.
The second was that the check to update records only checked one of the
filter hashes. It needs to test both the "filter" and "notrace" hashes.
The "filter" hash determines what functions to trace where as the "notrace"
hash determines what functions not to trace (trace all but these).
Both hashes need to be passed to the update code to find out what change
is being done during the update. This also broke the ftrace record
accounting and triggered a ftrace_bug().
This patch set also include two more fixes that were reported separately
from the kprobe issue.
One was that init_ftrace_syscalls() was called twice at boot up.
This is not a major bug, but that call performed a rather large kmalloc
(NR_syscalls * sizeof(*syscalls_metadata)). The second call made the first
one a memory leak, and wastes memory.
The other fix is a regression caused by an update in the v3.19 merge window.
The moving to enable events early, moved the enabling before PID 1 was
created. The syscall events require setting the TIF_SYSCALL_TRACEPOINT
for all tasks. But for_each_process_thread() does not include the swapper
task (PID 0), and ended up being a nop. A suggested fix was to add
the init_task() to have its flag set, but I didn't really want to mess
with PID 0 for this minor bug. Instead I disable and re-enable events again
at early_initcall() where it use to be enabled. This also handles any other
event that might have its own reg function that could break at early
boot up.
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Merge tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fixes from Steven Rostedt:
"This holds a few fixes to the ftrace infrastructure as well as the
mixture of function graph tracing and kprobes.
When jprobes and function graph tracing is enabled at the same time it
will crash the system:
# modprobe jprobe_example
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
After the first fork (jprobe_example probes it), the system will
crash.
This is due to the way jprobes copies the stack frame and does not do
a normal function return. This messes up with the function graph
tracing accounting which hijacks the return address from the stack and
replaces it with a hook function. It saves the return addresses in a
separate stack to put back the correct return address when done. But
because the jprobe functions do not do a normal return, their stack
addresses are not put back until the function they probe is called,
which means that the probed function will get the return address of
the jprobe handler instead of its own.
The simple fix here was to disable function graph tracing while the
jprobe handler is being called.
While debugging this I found two minor bugs with the function graph
tracing.
The first was about the function graph tracer sharing its function
hash with the function tracer (they both get filtered by the same
input). The changing of the set_ftrace_filter would not sync the
function recording records after a change if the function tracer was
disabled but the function graph tracer was enabled. This was due to
the update only checking one of the ops instead of the shared ops to
see if they were enabled and should perform the sync. This caused the
ftrace accounting to break and a ftrace_bug() would be triggered,
disabling ftrace until a reboot.
The second was that the check to update records only checked one of
the filter hashes. It needs to test both the "filter" and "notrace"
hashes. The "filter" hash determines what functions to trace where as
the "notrace" hash determines what functions not to trace (trace all
but these). Both hashes need to be passed to the update code to find
out what change is being done during the update. This also broke the
ftrace record accounting and triggered a ftrace_bug().
This patch set also include two more fixes that were reported
separately from the kprobe issue.
One was that init_ftrace_syscalls() was called twice at boot up. This
is not a major bug, but that call performed a rather large kmalloc
(NR_syscalls * sizeof(*syscalls_metadata)). The second call made the
first one a memory leak, and wastes memory.
The other fix is a regression caused by an update in the v3.19 merge
window. The moving to enable events early, moved the enabling before
PID 1 was created. The syscall events require setting the
TIF_SYSCALL_TRACEPOINT for all tasks. But for_each_process_thread()
does not include the swapper task (PID 0), and ended up being a nop.
A suggested fix was to add the init_task() to have its flag set, but I
didn't really want to mess with PID 0 for this minor bug. Instead I
disable and re-enable events again at early_initcall() where it use to
be enabled. This also handles any other event that might have its own
reg function that could break at early boot up"
* tag 'trace-fixes-v3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix enabling of syscall events on the command line
tracing: Remove extra call to init_ftrace_syscalls()
ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing
ftrace: Check both notrace and filter for old hash
ftrace: Fix updating of filters for shared global_ops filters
This patch partially reverts commit 421520ba98
(only the arm64 part). There is no guarantee that the boot-loader places other
images like dtb in a different page than initrd start/end, especially when the
kernel is built with 64KB pages. When this happens, such pages must not be
freed. The free_reserved_area() already takes care of rounding up "start" and
rounding down "end" to avoid freeing partially used pages.
Cc: <stable@vger.kernel.org> # 3.17+
Reported-by: Peter Maydell <Peter.Maydell@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
cycles:p and cycles:pp do not work on SLM since commit:
86a04461a9 ("perf/x86: Revamp PEBS event selection")
UOPS_RETIRED.ALL is not a PEBS capable event, so it should not be used
to count cycle number.
Actually SLM calls intel_pebs_aliases_core2() which uses INST_RETIRED.ANY_P
to count the number of cycles. It's a PEBS capable event. But inv and
cmask must be set to count cycles.
Considering SLM allows all events as PEBS with no flags, only
INST_RETIRED.ANY_P, inv=1, cmask=16 needs to handled specially.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421084541-31639-1-git-send-email-kan.liang@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a problem with the initialization of the
sysfs_show() routine for the RAPL PMU.
The current code was wrongly relying on the EVENT_ATTR_STR()
macro which uses the events_sysfs_show() function in the x86
PMU code. That function itself was relying on the x86_pmu data
structure. Yet RAPL and the core PMU (x86_pmu) have nothing to
do with each other. They should therefore not interact with
each other.
The x86_pmu structure is initialized at boot time based on
the host CPU model. When the host CPU is not supported, the
x86_pmu remains uninitialized and some of the callbacks it
contains are NULL.
The false dependency with x86_pmu could potentially cause crashes
in case the x86_pmu is not initialized while the RAPL PMU is. This
may, for instance, be the case in virtualized environments.
This patch fixes the problem by using a private sysfs_show()
routine for exporting the RAPL PMU events.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150113225953.GA21525@thinkpad
Cc: vincent.weaver@maine.edu
Cc: jolsa@redhat.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
softnet_data.input_pkt_queue is protected by a spinlock that
we must hold when transferring packets from victim queue to an active
one. This is because other cpus could still be trying to enqueue packets
into victim queue.
A second problem is that when we transfert the NAPI poll_list from
victim to current cpu, we absolutely need to special case the percpu
backlog, because we do not want to add complex locking to protect
process_queue : Only owner cpu is allowed to manipulate it, unless cpu
is offline.
Based on initial patch from Prasad Sodagudi & Subash Abhinov
Kasiviswanathan.
This version is better because we do not slow down packet processing,
only make migration safer.
Reported-by: Prasad Sodagudi <psodagud@codeaurora.org>
Reported-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tony Lindgren says:
====================
Fixes for davinci_emac
Here's a repost of the fixes for davinci_emac with patches
updated for comments and acks collected.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
On dm816x we have two emac controllers with separate memory
areas.
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some devices like dm816x have the MDIO registers within the first EMAC
instance address space. Let's fix the issue by allowing to pass an
optional second IO range for the EMAC control register area.
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Looks like the phy_id is never set up beyond getting the phandle.
Note that we can remove the ifdef for phy_node as there is a stub
for of_phy_connec() if CONFIG_OF is not set.
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We only use clk_get() to get the frequency, the rest is done by
the runtime PM calls. Let's free the clock too.
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 3ba9738134 ("net: ethernet: davinci_emac: add pm_runtime support")
added support for runtime PM, but it causes issues on omap3 related devices
that actually gate the clocks:
Unhandled fault: external abort on non-linefetch (0x1008)
...
[<c04160f0>] (emac_dev_getnetstats) from [<c04d6a3c>] (dev_get_stats+0x78/0xc8)
[<c04d6a3c>] (dev_get_stats) from [<c04e9ccc>] (rtnl_fill_ifinfo+0x3b8/0x938)
[<c04e9ccc>] (rtnl_fill_ifinfo) from [<c04eade4>] (rtmsg_ifinfo+0x68/0xd8)
[<c04eade4>] (rtmsg_ifinfo) from [<c04dd35c>] (register_netdevice+0x3a0/0x4ec)
[<c04dd35c>] (register_netdevice) from [<c04dd4bc>] (register_netdev+0x14/0x24)
[<c04dd4bc>] (register_netdev) from [<c041755c>] (davinci_emac_probe+0x408/0x5c8)
[<c041755c>] (davinci_emac_probe) from [<c0396d78>] (platform_drv_probe+0x48/0xa4)
Let's fix it by moving the pm_runtime_get() call earlier, and also add it to
the emac_dev_getnetstats(). Also note that we want to use pm_runtime_get_sync()
as we don't want to have deferred_resume happen. And let's also check the
return value for pm_runtime_get_sync() as noted by Felipe Balbi <balbi@ti.com>.
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On davinci_emac, we have pulse interrupts. This means that we need to
clear the EOI bits when disabling interrupts as otherwise the interrupts
keep happening. And we also need to not clear the EOI bits again when
enabling the interrupts as otherwise we will get tons of:
unexpected IRQ trap at vector 00
These errors almost certainly mean that the omap-intc.c is signaling
a spurious interrupt with the reserved irq 127 as we've seen earlier
on omap3.
Let's fix the issue by clearing the EOI bits when disabling the
interrupts. Let's also keep the comment for "Rx Threshold and Misc
interrupts are not enabled" for both enable and disable so people
are aware of this when potentially adding more support.
Note that eventually we should handle the RX and TX interrupts
separately like cpsw is now doing. However, so far I have not seen
any issues with this based on my testing, so it seems to behave a
little different compared to the cpsw that had a similar issue.
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull fuse fixes from Miklos Szeredi:
"This fixes a regression in the latest fuse update plus a fix for a
rather theoretical memory ordering issue"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: add memory barrier to INIT
fuse: fix LOOKUP vs INIT compat handling
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Merge tag 'powerpc-3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc fixes from Michael Ellerman:
"A few powerpc fixes"
* tag 'powerpc-3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
powerpc: Work around gcc bug in current_thread_info()
cxl: Fix issues when unmapping contexts
powernv: Fix OPAL tracepoint code
The sockaddr is returned in IP(V6)_RECVERR as part of errhdr. That
structure is defined and allocated on the stack as
struct {
struct sock_extended_err ee;
struct sockaddr_in(6) offender;
} errhdr;
The second part is only initialized for certain SO_EE_ORIGIN values.
Always initialize it completely.
An MTU exceeded error on a SOCK_RAW/IPPROTO_RAW is one example that
would return uninitialized bytes.
Signed-off-by: Willem de Bruijn <willemb@google.com>
----
Also verified that there is no padding between errhdr.ee and
errhdr.offender that could leak additional kernel data.
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'linux-can-fixes-for-3.19-20150115' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can
Marc Kleine-Budde says:
====================
pull-request: can 2015-01-15
this is a pull request of 8 patches.
Ahmed S. Darwish contributes 4 fixes for the kvaser_usb driver. The two patches
by Oliver Hartkopp mark the m_can driver as non-ISO, as the CANFD standard was
updated. Roger Quadros's patch for the c_can driver fixes the register access
during RAMINIT. And one patch by my, which updates the MAINTAINERS file, as we
moved the git repos to the kernel.org infrastructure.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Except for VXLAN steering rules, all offloads should work as they were
under plain DMFS mode. Fix that by enabling all the offloads under
DMFS-A0 mode, except for VXLAN steering rules.
Fixes: d57febe1a4 "net/mlx4: Add A0 hybrid steering"
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
one for a deadlock in regulatory processing.
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Merge tag 'mac80211-for-davem-2015-01-15' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211
Just two fixes - one for an uninialized variable and
one for a deadlock in regulatory processing.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes double kfree() calls at init_rx_ring() because
it causes static checker warning.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the MAC address is provided in the device tree file, the
condition is true and kernel crashes due to NULL dereference.
Signed-off-by: Girish K.S <ks.giri@samsung.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit b284fbe3b3 ("sh_eth: Fix access to TRSCER register") wanted
to add a .trscer_err_mask value to the R-Car Gen2 family-specific data
structure (r8a779x_data), but it was accidentally added to the
SH7724-specific data structure (sh7724_data).
Presumably this happened due to a patch conflict with commit
d407bc0203 ("sh-eth: Set fdr_value of R-Car SoCs"), which added
another field at the same position.
Move the field setting to fix this.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: b284fbe3b3 ("sh_eth: Fix access to TRSCER register")
Signed-off-by: David S. Miller <davem@davemloft.net>
while adding vlan in dual EMAC mode, only specific ports should be
subscribed for the vlan, else it will lead to switching mode and
if both ports connected to same switch cpsw will hung as it creates
a network loop. Fixing this by adding only specific ports in case
of dual EMAC.
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
of_get_named_gpiod_flags fails with -EPROBE_DEFER in cases
where the gpio chip is available and the GPIO translation fails.
This causes drivers to be re-probed erroneusly, and hides the
real problem(i.e. the GPIO number being out of range).
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Hans Holmberg <hans.holmberg@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fix attribute-creation race with userspace by using the default group
to create also the contingent gpio device attributes.
Fixes: d8f388d8dc ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The gpio device attributes were never destroyed when the gpio was
unexported (or on export failures).
Use device_create_with_groups() to create the default device attributes
of the gpio class device. Note that this also fixes the
attribute-creation race with userspace for these attributes.
Remove contingent attributes in export error path and on unexport.
Fixes: d8f388d8dc ("gpio: sysfs interface")
Cc: stable <stable@vger.kernel.org> # v2.6.27+
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The gpio-chip device attributes were never destroyed when the device was
removed.
Fix by using device_create_with_groups() to create the device attributes
of the chip class device.
Note that this also fixes the attribute-creation race with userspace.
Fixes: d8f388d8dc ("gpio: sysfs interface")
Cc: stable <stable@vger.kernel.org> # v2.6.27+
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We should not touch the packet after a netif_rx: it might
get freed behind our back.
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Recent Leaf firmware versions (>= 3.1.557) do not allow to send
commands for non-existing channels. If a command is sent for a
non-existing channel, the firmware crashes.
Reported-by: Christopher Storah <Christopher.Storah@invetech.com.au>
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Flooding the Kvaser CAN to USB dongle with multiple reads and
writes in very high frequency (*), closing the CAN channel while
all the transmissions are on (#), opening the device again (@),
then sending a small number of packets would make the driver
enter an almost infinite loop of:
[....]
[15959.853988] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853990] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853991] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853993] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853994] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853995] kvaser_usb 4-3:1.0 can0: cannot find free context
[....]
_dragging the whole system down_ in the process due to the
excessive logging output.
Initially, this has caused random panics in the kernel due to a
buggy error recovery path. That got fixed in an earlier commit.(%)
This patch aims at solving the root cause. -->
16 tx URBs and contexts are allocated per CAN channel per USB
device. Such URBs are protected by:
a) A simple atomic counter, up to a value of MAX_TX_URBS (16)
b) A flag in each URB context, stating if it's free
c) The fact that ndo_start_xmit calls are themselves protected
by the networking layers higher above
After grabbing one of the tx URBs, if the driver noticed that all
of them are now taken, it stops the netif transmission queue.
Such queue is worken up again only if an acknowedgment was received
from the firmware on one of our earlier-sent frames.
Meanwhile, upon channel close (#), the driver sends a CMD_STOP_CHIP
to the firmware, effectively closing all further communication. In
the high traffic case, the atomic counter remains at MAX_TX_URBS,
and all the URB contexts remain marked as active. While opening
the channel again (@), it cannot send any further frames since no
more free tx URB contexts are available.
Reset all tx URB contexts upon CAN channel close.
(*) 50 parallel instances of `cangen0 -g 0 -ix`
(#) `ifconfig can0 down`
(@) `ifconfig can0 up`
(%) "can: kvaser_usb: Don't free packets when tight on URBs"
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Flooding the Kvaser CAN to USB dongle with multiple reads and
writes in high frequency caused seemingly-random panics in the
kernel.
On further inspection, it seems the driver erroneously freed the
to-be-transmitted packet upon getting tight on URBs and returning
NETDEV_TX_BUSY, leading to invalid memory writes and double frees
at a later point in time.
Note:
Finding no more URBs/transmit-contexts and returning NETDEV_TX_BUSY
is a driver bug in and out of itself: it means that our start/stop
queue flow control is broken.
This patch only fixes the (buggy) error handling code; the root
cause shall be fixed in a later commit.
Acked-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
use of regmap_read() and regmap_write() in c_can_hw_raminit_syscon()
is not safe as the RAMINIT register can be shared between different drivers
at least for TI SoCs.
To make the modification atomic we switch to using regmap_update_bits().
regmap_update_bits() skips writing to the register if it's read content is the
same as what is going to be written. This causes an issue for us when we
need to clear the DONE bit with the initial condition START:0, DONE:1 as
DONE bit must be written with 1 to clear it.
So we defer the clearing of DONE bit to later when we set the START bit.
There we are sure that START bit is changed from 0 to 1 so the write of
1 to already set DONE bit will happen.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During the CAN FD standardization process within the ISO it turned out that
the failure detection capability has to be improved.
The CAN in Automation organization (CiA) defined the already implemented CAN
FD controllers as 'non-ISO' and the upcoming improved CAN FD controllers as
'ISO' compliant. See at http://www.can-cia.com/index.php?id=1937
Finally there will be three types of CAN FD controllers in the future:
1. ISO compliant (fixed)
2. non-ISO compliant (fixed, like the M_CAN IP v3.0.1 in m_can.c)
3. ISO/non-ISO CAN FD controllers (switchable, like the PEAK USB FD)
So the current M_CAN driver for the M_CAN IP v3.0.1 has to expose its non-ISO
implementation by setting the CAN_CTRLMODE_FD_NON_ISO ctrlmode at startup.
As this bit cannot be switched at configuration time CAN_CTRLMODE_FD_NON_ISO
must not be set in ctrlmode_supported of the current M_CAN driver.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
When changing flags in the CAN drivers ctrlmode the provided new content has to
be checked whether the bits are allowed to be changed. The bits that are to be
changed are given as a bitfield in cm->mask. Therefore checking against
cm->flags is wrong as the content can hold any kind of values.
The iproute2 tool sets the bits in cm->mask and cm->flags depending on the
detected command line options. To be robust against bogus user space
applications additionally sanitize the provided flags with the provided mask.
Cc: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The linux-can upstream git repositories are now hosted on kernel.org, update
MAINTAINERS accordingly.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Commit 5f893b2639 "tracing: Move enabling tracepoints to just after
rcu_init()" broke the enabling of system call events from the command
line. The reason was that the enabling of command line trace events
was moved before PID 1 started, and the syscall tracepoints require
that all tasks have the TIF_SYSCALL_TRACEPOINT flag set. But the
swapper task (pid 0) is not part of that. Since the swapper task is the
only task that is running at this early in boot, no task gets the
flag set, and the tracepoint never gets reached.
Instead of setting the swapper task flag (there should be no reason to
do that), re-enabled trace events again after the init thread (PID 1)
has been started. It requires disabling all command line events and
re-enabling them, as just enabling them again will not reset the logic
to set the TIF_SYSCALL_TRACEPOINT flag, as the syscall tracepoint will
be fooled into thinking that it was already set, and wont try setting
it again. For this reason, we must first disable it and re-enable it.
Link: http://lkml.kernel.org/r/1421188517-18312-1-git-send-email-mpe@ellerman.id.au
Link: http://lkml.kernel.org/r/20150115040506.216066449@goodmis.org
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
trace_init() calls init_ftrace_syscalls() and then calls trace_event_init()
which also calls init_ftrace_syscalls(). It makes more sense to only
call it from trace_event_init().
Calling it twice wastes memory, as it allocates the syscall events twice,
and loses the first copy of it.
Link: http://lkml.kernel.org/r/54AF53BD.5070303@huawei.com
Link: http://lkml.kernel.org/r/20150115040505.930398632@goodmis.org
Reported-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
If the function graph tracer traces a jprobe callback, the system will
crash. This can easily be demonstrated by compiling the jprobe
sample module that is in the kernel tree, loading it and running the
function graph tracer.
# modprobe jprobe_example.ko
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# ls
The first two commands end up in a nice crash after the first fork.
(do_fork has a jprobe attached to it, so "ls" just triggers that fork)
The problem is caused by the jprobe_return() that all jprobe callbacks
must end with. The way jprobes works is that the function a jprobe
is attached to has a breakpoint placed at the start of it (or it uses
ftrace if fentry is supported). The breakpoint handler (or ftrace callback)
will copy the stack frame and change the ip address to return to the
jprobe handler instead of the function. The jprobe handler must end
with jprobe_return() which swaps the stack and does an int3 (breakpoint).
This breakpoint handler will then put back the saved stack frame,
simulate the instruction at the beginning of the function it added
a breakpoint to, and then continue on.
For function tracing to work, it hijakes the return address from the
stack frame, and replaces it with a hook function that will trace
the end of the call. This hook function will restore the return
address of the function call.
If the function tracer traces the jprobe handler, the hook function
for that handler will not be called, and its saved return address
will be used for the next function. This will result in a kernel crash.
To solve this, pause function tracing before the jprobe handler is called
and unpause it before it returns back to the function it probed.
Some other updates:
Used a variable "saved_sp" to hold kcb->jprobe_saved_sp. This makes the
code look a bit cleaner and easier to understand (various tries to fix
this bug required this change).
Note, if fentry is being used, jprobes will change the ip address before
the function graph tracer runs and it will not be able to trace the
function that the jprobe is probing.
Link: http://lkml.kernel.org/r/20150114154329.552437962@goodmis.org
Cc: stable@vger.kernel.org # 2.6.30+
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Using just the filter for checking for trampolines or regs is not enough
when updating the code against the records that represent all functions.
Both the filter hash and the notrace hash need to be checked.
To trigger this bug (using trace-cmd and perf):
# perf probe -a do_fork
# trace-cmd start -B foo -e probe
# trace-cmd record -p function_graph -n do_fork sleep 1
The trace-cmd record at the end clears the filter before it disables
function_graph tracing and then that causes the accounting of the
ftrace function records to become incorrect and causes ftrace to bug.
Link: http://lkml.kernel.org/r/20150114154329.358378039@goodmis.org
Cc: stable@vger.kernel.org
[ still need to switch old_hash_ops to old_ops_hash ]
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
