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There is no need to check port for NULL in uart_port_deref() since we call it
only when port is defined.
There are few places that violate this. Fix them here as well.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes:
Fourth set of IIO new device support, features and cleaups for the 4.10 cycle.
Probably the final set before the merge window unless things get significantly
delayed.
New device support
* STM32 ADC core
- new driver. Interesting device with up to 3 ADCs with complex triggering
options that will follow later. Note split into an 'mfd like' core that
handles the interrupt sharing etc between the various instances present and
a per ADC section that is instantiated as many times as needed.
- device tree bindings.
Cleanups and minor fixes
* st_accel
- inline per sensor data as the defines don't add any meaning and make it
much harder to check if a given sensor has the right values.
* hid-magnetometer
- sort out the associations of the associated attributes with the two types.
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Remove the ugly sparse casts by using the helper u64_to_user_ptr()
instead.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161127170910.29106-1-chris@chris-wilson.co.uk
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start is being used as both a macro parameter and as a member of struct
drm_mm_node (node->start). This causes a conflict as cpp then tries to
replace node->start with the passed in string for "start". Work just
fine so long as you also happened to using local variables called start!
Fixes: 522e85dd8677 ("drm: Define drm_mm_for_each_node_in_range()")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>.
[danvet: Fixup kerneldoc.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161127111623.11124-1-chris@chris-wilson.co.uk
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In x86's include/asm/Kbuild three entries are appended to the genhdr-y make
variable:
genhdr-y += unistd_32.h
genhdr-y += unistd_64.h
genhdr-y += unistd_x32.h
The same entries are also appended to that variable in
include/uapi/asm/Kbuild. So commit:
10b63956fce7 ("UAPI: Plumb the UAPI Kbuilds into the user header installation and checking")
... removed these three entries from include/asm/Kbuild. But, apparently, some
merge conflict resolution re-added them.
The net effect is, in short, that the genhdr-y make variable contains these
file names twice and, as a consequence, that the corresponding headers get
installed twice. And so the build prints:
INSTALL usr/include/asm/ (65 files)
... while in reality only 62 files are installed in that directory.
Nothing breaks because of all that, but it's a good idea to finally remove
these unneeded entries nevertheless.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1480077707-2837-1-git-send-email-pebolle@tiscali.nl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The make variable KBUILD_CFLAGS contains $(LINUXINCLUDE). But the build
already picks up $(LINUXINCLUDE) from scripts/Makefile.lib. The net effect
is that the (long) list of include directories is used twice.
This is harmless but pointless. So stop using $(LINUXINCLUDE) twice.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1480077514-2586-1-git-send-email-pebolle@tiscali.nl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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My attempt at fixing some KASAN false positive warnings was rather brain
dead, and it broke the guess unwinder. With frame pointers disabled,
/proc/<pid>/stack is broken:
# cat /proc/1/stack
[<ffffffffffffffff>] 0xffffffffffffffff
Restore the code flow to more closely resemble its previous state, while
still using READ_ONCE_NOCHECK() macros to silence KASAN false positives.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: c2d75e03d630 ("x86/unwind: Prevent KASAN false positive warnings in guess unwinder")
Link: http://lkml.kernel.org/r/b824f92c2c22eca5ec95ac56bd2a7c84cf0b9df9.1480309971.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Fixes below warning with clang:
In file included from ../arch/x86/tools/relocs_64.c:17:
../arch/x86/tools/relocs.c:977:6: warning: variable 'do_reloc' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161126222229.673-1-pefoley2@pefoley.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Fix:
arch/x86/platform/olpc/olpc-xo15-sci.c:199:12: warning: ‘xo15_sci_resume’
defined but not used [-Wunused-function]
static int xo15_sci_resume(struct device *dev)
^
which I see in randconfig builds here.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161126142706.13602-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Single-stepping through head_64.S made me look at the fixmap page PTEs
fixup loop:
So we're going through the whole level2_fixmap_pgt 4K page, looking at
whether PAGE_PRESENT is set in those PTEs and add the delta between
where we're compiled to run and where we actually end up running.
However, if that delta is 0 (most cases) we go through all those 512
PTEs for no reason at all. Oh well, we add 0 but that's no reason to me.
Skipping that useless fixup gives us a boot speedup of 0.004 seconds in
my guest. Not a lot but considering how cheap it is, I'll take it. Here
is the printk time difference:
before:
...
[ 0.000000] tsc: Marking TSC unstable due to TSCs unsynchronized
[ 0.013590] Calibrating delay loop (skipped), value calculated using timer frequency..
8027.17 BogoMIPS (lpj=16054348)
[ 0.017094] pid_max: default: 32768 minimum: 301
...
after:
...
[ 0.000000] tsc: Marking TSC unstable due to TSCs unsynchronized
[ 0.009587] Calibrating delay loop (skipped), value calculated using timer frequency..
8026.86 BogoMIPS (lpj=16053724)
[ 0.013090] pid_max: default: 32768 minimum: 301
...
For the other two changes converting naked numbers to defines:
# arch/x86/kernel/head_64.o:
text data bss dec hex filename
1124 290864 4096 296084 48494 head_64.o.before
1124 290864 4096 296084 48494 head_64.o.after
md5:
87086e202588939296f66e892414ffe2 head_64.o.before.asm
87086e202588939296f66e892414ffe2 head_64.o.after.asm
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161125111448.23623-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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We need to call drm_helper_hpd_irq_event() on resume to properly detect
monitor connection / disconnection on some laptops, use hpd_work for
this to avoid deadlocks.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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We need to call drm_helper_hpd_irq_event() on resume to properly detect
monitor connection / disconnection on some laptops. For runtime-resume
(which gets called on resume from normal suspend too) we must call
drm_helper_hpd_irq_event() from a workqueue to avoid a deadlock.
Rename acpi_work to hpd_work, and move it out of the #ifdef CONFIG_ACPI
blocks to make it suitable for generic work.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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The new atomic modesetting/pageflip code for nv50+ for
Linux 4.10+ no longer uses pageflip irq's to signal
flip completion. Instead it polls for flip completion
from within a kthread/work queue.
This creates a race between the vblank irq handler
updating the vblank count and timestamp for the
vblank of flip completion, and the kthread's
polling code detecting flip completion and sending
out the flip completion event.
Depending on who executes a few microseconds earlier,
the flip completion event will either contain correct
count/timestamp or a stale count/timestamp from the
previous vblank. This error was observed for about
50% of all executed flips, e.g., observable under DRI2
by the Xorg.log filling with flip handler warning
messages.
Call drm_accurate_vblank_count() before sending
out flip completion events to enforce a vblank
count/ts update for the vblank of flip completion
and avoid stale counts/timestamps.
This fix leads to one redundant call to drm_update_vblank_count
for each completed flip, but no other side effects. On
a ~6 year old Core i7 M620@ 2.67GHz the redundant call
costs about 10 usecs per flip
Successfully tested on GeForce 9500/9600/330M so far.
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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In this situation, we'd have ended up detecting less VRAM than we have.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Daniel Borkmann says:
====================
BPF cleanups and misc updates
This patch set adds couple of cleanups in first few patches,
exposes owner_prog_type for array maps as well as mlocked mem
for maps in fdinfo, allows for mount permissions in fs and
fixes various outstanding issues in selftests and samples.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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1) The test_lru_map and test_lru_dist fails building on my machine since
the sys/resource.h header is not included.
2) test_verifier fails in one test case where we try to call an invalid
function, since the verifier log output changed wrt printing function
names.
3) Current selftest suite code relies on sysconf(_SC_NPROCESSORS_CONF) for
retrieving the number of possible CPUs. This is broken at least in our
scenario and really just doesn't work.
glibc tries a number of things for retrieving _SC_NPROCESSORS_CONF.
First it tries equivalent of /sys/devices/system/cpu/cpu[0-9]* | wc -l,
if that fails, depending on the config, it either tries to count CPUs
in /proc/cpuinfo, or returns the _SC_NPROCESSORS_ONLN value instead.
If /proc/cpuinfo has some issue, it returns just 1 worst case. This
oddity is nothing new [1], but semantics/behaviour seems to be settled.
_SC_NPROCESSORS_ONLN will parse /sys/devices/system/cpu/online, if
that fails it looks into /proc/stat for cpuX entries, and if also that
fails for some reason, /proc/cpuinfo is consulted (and returning 1 if
unlikely all breaks down).
While that might match num_possible_cpus() from the kernel in some
cases, it's really not guaranteed with CPU hotplugging, and can result
in a buffer overflow since the array in user space could have too few
number of slots, and on perpcu map lookup, the kernel will write beyond
that memory of the value buffer.
William Tu reported such mismatches:
[...] The fact that sysconf(_SC_NPROCESSORS_CONF) != num_possible_cpu()
happens when CPU hotadd is enabled. For example, in Fusion when
setting vcpu.hotadd = "TRUE" or in KVM, setting ./qemu-system-x86_64
-smp 2, maxcpus=4 ... the num_possible_cpu() will be 4 and sysconf()
will be 2 [2]. [...]
Documentation/cputopology.txt says /sys/devices/system/cpu/possible
outputs cpu_possible_mask. That is the same as in num_possible_cpus(),
so first step would be to fix the _SC_NPROCESSORS_CONF calls with our
own implementation. Later, we could add support to bpf(2) for passing
a mask via CPU_SET(3), for example, to just select a subset of CPUs.
BPF samples code needs this fix as well (at least so that people stop
copying this). Thus, define bpf_num_possible_cpus() once in selftests
and import it from there for the sample code to avoid duplicating it.
The remaining sysconf(_SC_NPROCESSORS_CONF) in samples are unrelated.
After all three issues are fixed, the test suite runs fine again:
# make run_tests | grep self
selftests: test_verifier [PASS]
selftests: test_maps [PASS]
selftests: test_lru_map [PASS]
selftests: test_kmod.sh [PASS]
[1] https://www.sourceware.org/ml/libc-alpha/2011-06/msg00079.html
[2] https://www.mail-archive.com/netdev@vger.kernel.org/msg121183.html
Fixes: 3059303f59cf ("samples/bpf: update tracex[23] examples to use per-cpu maps")
Fixes: 86af8b4191d2 ("Add sample for adding simple drop program to link")
Fixes: df570f577231 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_ARRAY")
Fixes: e15596717948 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_HASH")
Fixes: ebb676daa1a3 ("bpf: Print function name in addition to function id")
Fixes: 5db58faf989f ("bpf: Add tests for the LRU bpf_htab")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: William Tu <u9012063@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Since we recently converted the BPF filesystem over to use mount_nodev(),
we now have the possibility to also hold mount options in sb's s_fs_info.
This work implements mount options support for specifying permissions on
the sb's inode, which will be used by tc when it manually needs to mount
the fs.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Allow for checking the owner_prog_type of a program array map. In some
cases bpf(2) can return -EINVAL /after/ the verifier passed and did all
the rewrites of the bpf program.
The reason that lets us fail at this late stage is that program array
maps are incompatible. Allow users to inspect this earlier after they
got the map fd through BPF_OBJ_GET command. tc will get support for this.
Also, display how much we charged the map with regards to RLIMIT_MEMLOCK.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit dcf800344a91 ("net/sched: act_mirred: Refactor detection whether
dev needs xmit at mac header") added dev_is_mac_header_xmit(); since it's
also useful elsewhere, move it to if_arp.h and reuse it for BPF.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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After setup we don't need to keep user space fd number around anymore, as
it also has no useful meaning for anyone, just remove it.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Since long already bpf_func is not only about struct sk_buff * as
input anymore. Make it generic as void *, so that callers don't
need to cast for it each time they call BPF_PROG_RUN().
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In commit e4bf4f76962b ("tipc: simplify packet sequence number
handling") we changed the internal representation of the packet
sequence number counters from u32 to u16, reflecting what is really
sent over the wire.
Since then some link statistics counters have been displaying incorrect
values, partially because the counters meant to be used as sequence
number snapshots are now used as direct counters, stored as u32, and
partially because some counter updates are just missing in the code.
In this commit we correct this in two ways. First, we base the
displayed packet sent/received values on direct counters instead
of as previously a calculated difference between current sequence
number and a snapshot. Second, we add the missing updates of the
counters.
This change is compatible with the current netlink API, and requires
no changes to the user space tools.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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We don't use ->heap_buf after commit 46d1efd852cc ("sfc: remove Software
TSO") so let's remove the last traces.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next
Kalle Valo says:
====================
wireless-drivers-next patches for 4.10
Major changes:
iwlwifi
* finalize and enable dynamic queue allocation
* use dev_coredumpmsg() to prevent locking the driver
* small fix to pass the AID to the FW
* use FW PS decisions with multi-queue
ath9k
* add device tree bindings
* switch to use mac80211 intermediate software queues to reduce
latency and fix bufferbloat
wl18xx
* allow scanning in AP mode
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:
====================
pull request (net): ipsec 2016-11-25
1) Fix a refcount leak in vti6.
From Nicolas Dichtel.
2) Fix a wrong if statement in xfrm_sk_policy_lookup.
From Florian Westphal.
3) The flowcache watermarks are per cpu. Take this into
account when comparing to the threshold where we
refusing new allocations. From Miroslav Urbanek.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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The macvtap_newlink registers the netdev rx_handler firstly, but it
does not unregister the handler if macvlan_common_newlink failed.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Johan Hovold says:
====================
net: fix phydev reference leaks
This series fixes a number of phydev reference leaks (and one of_node
leak) due to failure to put the reference taken by of_phy_find_device().
Note that I did not try to fix drivers/net/phy/xilinx_gmii2rgmii.c which
still leaks a reference.
Against net but should apply just as fine to net-next.
v2:
- use put_device() instead of phy_dev_free() to put the references
taken in net/dsa (patch 1/4).
- add four new patches fixing similar leaks
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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Make sure to drop the reference taken by of_phy_find_device() during
probe on probe errors and on driver unbind.
Also drop the of_node reference taken by of_parse_phandle() in the same
path.
Fixes: b9b17debc69d ("net: emac: emac gigabit ethernet controller driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Make sure to drop the reference taken by of_phy_find_device() when
looking up a fixed-link phydev during probe.
Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Make sure to drop the reference taken by of_phy_find_device() during
initialisation when later freeing the struct fman_mac.
Fixes: 57ba4c9b56d8 ("fsl/fman: Add FMan MAC support")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Make sure to drop the reference taken by of_phy_find_device() when
initialising MOCA PHYs.
Fixes: 6ac9de5f6563 ("net: bcmgenet: Register link_update callback for
all MoCA PHYs")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Make sure to drop the reference taken by of_phy_find_device() when
registering and deregistering the fixed-link PHY-device.
Fixes: 39b0c705195e ("net: dsa: Allow configuration of CPU & DSA port
speeds/duplex")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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irda_get_mtt() returns a hardcoded '10000' in some cases,
and with gcc-7, we get a build error because this triggers a
compile-time check in udelay():
drivers/net/irda/w83977af_ir.o: In function `w83977af_hard_xmit':
w83977af_ir.c:(.text.w83977af_hard_xmit+0x14c): undefined reference to `__bad_udelay'
Older compilers did not run into this because they either did not
completely inline the irda_get_mtt() or did not consider the
10000 value a constant expression.
The code has been wrong since the start of git history.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When ipvlan_link_new fails and creates one ipvlan port, it does not
destroy the ipvlan port created. It causes mem leak and the physical
device contains invalid ipvlan data.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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There is currently no documentation about the halt polling capabilities
of the kvm module. Add some documentation describing the mechanism as well
as the module parameters to all better understanding of how halt polling
should be used and the effect of tuning the module parameters.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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Fix comment block to match kernel comment style.
Fix print format from signed to unsigned.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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KVM_HALT_POLL_NS_DEFAULT is an arch specific constant which sets the
default value of the halt_poll_ns kvm module parameter which determines
the global maximum halt polling interval.
The current value for powerpc is 500000 (500us) which means that any
repetitive workload with a period of less than that can drive the cpu
usage to 100% where it may have been mostly idle without halt polling.
This presents the possibility of a large increase in power usage with
a comparatively small performance benefit.
Reduce the default to 10000 (10us) and a user can tune this themselves
to set their affinity for halt polling based on the trade off between power
and performance which they are willing to make.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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The kvm module parameter halt_poll_ns defines the global maximum halt
polling interval and can be dynamically changed by writing to the
/sys/module/kvm/parameters/halt_poll_ns sysfs file. However in kvm-hv
this module parameter value is only ever checked when we grow the current
polling interval for the given vcore. This means that if we decrease the
halt_poll_ns value below the current polling interval we won't see any
effect unless we try to grow the polling interval above the new max at some
point or it happens to be shrunk below the halt_poll_ns value.
Update the halt polling code so that we always check for a new module param
value of halt_poll_ns and set the current halt polling interval to it if
it's currently greater than the new max. This means that it's redundant to
also perform this check in the grow_halt_poll_ns() function now.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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The previous patch exported the variables which back the module parameters
of the generic kvm module. Now use these variables in the kvm-hv module
so that any change to the generic module parameters will also have the
same effect for the kvm-hv module. This removes the duplication of the
kvm module parameters which was redundant and should reduce confusion when
tuning them.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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The kvm module has the parameters halt_poll_ns, halt_poll_ns_grow, and
halt_poll_ns_shrink. Halt polling was recently added to the powerpc kvm-hv
module and these parameters were essentially duplicated for that. There is
no benefit to this duplication and it can lead to confusion when trying to
tune halt polling.
Thus move the definition of these variables to kvm_host.h and export them.
This will allow the kvm-hv module to use the same module parameters by
accessing these variables, which will be implemented in the next patch,
meaning that they will no longer be duplicated.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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