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This function error patch can be simplified, so do so.
Remove fail: label and somewhat obfuscating, used once "error_path"
function.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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This is necessary so that - if ath10k is the only driver using
dev_coredump*() - the functionality is built into the kernel.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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This now declares a module parameter, so include the necessary
header file for that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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Remove redundant semicolon after switch statement.
Signed-off-by: Waldemar Rymarkiewicz <ext.waldemar.rymarkiewicz@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
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The sysfs cpu_capacity entry for each CPU has nothing to do with
PROC_FS, nor it's in /proc/sys path.
Remove such ifdef.
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-and-suggested-by: Sudeep Holla <sudeep.holla@arm.com>
Fixes: be8f185d8af4 ('arm64: add sysfs cpu_capacity attribute')
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
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Commit 680a0873e193 ("arm: kernel: Add SMC structure parameter") added
a new "quirk" parameter to the SMC and HVC SMCCC backends, but only
updated the comment for the SMC version. This patch adds the new
paramater to the comment describing the HVC version too.
Signed-off-by: Will Deacon <will.deacon@arm.com>
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Some local interrupts are not initialised properly at the moment and
cannot be used since the domain's alloc method is never called for them.
This has been observed earlier and partially fixed in commit
e875bd66dfb ("irqchip/mips-gic: Fix local interrupts"), but that change
still relied on the interrupt to be requested by an external driver (eg.
drivers/clocksource/mips-gic-timer.c).
This does however not solve the issue for interrupts that are not
referenced by any driver through the device tree and results in
request_irq() calls returning -ENOSYS. It can be observed when attempting
to use perf tool to access hardware performance counters.
Fix this by explicitly calling irq_create_fwspec_mapping() for local
interrupts.
Fixes: e875bd66dfb ("irqchip/mips-gic: Fix local interrupts")
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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After removing DEBUG from mtk_vcodec_util.h, some build warnings are
generated as the following:
.../drivers/media/platform/mtk-vcodec/vdec_vpu_if.c: In function 'vcodec_vpu_send_msg':
.../drivers/media/platform/mtk-vcodec/vdec_vpu_if.c:73:11: warning: unused variable 'msg_id' [-Wunused-variable]
uint32_t msg_id = *(uint32_t *)msg;
^
.../drivers/media/platform/mtk-vcodec/mtk_vcodec_dec.c: In function 'vb2ops_vdec_buf_queue':
.../drivers/media/platform/mtk-vcodec/mtk_vcodec_dec.c:1129:7: warning: unused variable 'log_level' [-Wunused-variable]
int log_level = ret ? 0 : 1;
^
.../drivers/media/platform/mtk-vcodec/venc_vpu_if.c: In function 'vpu_enc_send_msg':
.../drivers/media/platform/mtk-vcodec/venc_vpu_if.c:82:12: warning: unused variable 'msg_id' [-Wunused-variable]
uint32_t msg_id = *(uint32_t *)msg;
^
It is because mtk_vcodec_debug() and mtk_vcodec_err() are defined as empty
macros. Without DEBUG definition, the variable for debugging is not used
anymore. Fixing build warnings by moving the assignment of the
variable to the argument of mtk_vcodec_debug() and mtk_vcodec_err().
Within the patch, build pass with/without DEBUG definition, and functions
still work fine.
Signed-off-by: Minghsiu Tsai <minghsiu.tsai@mediatek.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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As a part of transitioning the Gemini platform to device tree we
create this clean, device-tree-only irqchip driver.
Cc: Janos Laube <janos.dev@gmail.com>
Cc: Paulius Zaleckas <paulius.zaleckas@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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This adds device tree bindings for the Cortina Gemini interrupt
controller. They are pretty standard.
Cc: Janos Laube <janos.dev@gmail.com>
Cc: Paulius Zaleckas <paulius.zaleckas@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: devicetree@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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If the USB driver is enabled but the demodulator is not, we get a link error:
ERROR: "zd1301_demod_get_dvb_frontend" [drivers/media/usb/dvb-usb-v2/zd1301.ko] undefined!
ERROR: "zd1301_demod_get_i2c_adapter" [drivers/media/usb/dvb-usb-v2/zd1301.ko] undefined!
Such a configuration obviously makes no sense, but we should not fail
the build. This tries to mimic what we have for other drivers by turning
the build failure into a runtime failure.
Alternatively we could use an unconditional 'select' or 'depends on' to enforce
a sane configuration.
Fixes: 47d65372b3b6 ("[media] zd1301_demod: ZyDAS ZD1301 DVB-T demodulator driver")
Fixes: 992b39872b80 ("[media] zd1301: ZyDAS ZD1301 DVB USB interface driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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GICD_TYPER_LPIS macro is defined twice in this file. This patch removes the
duplicate entry.
Fixes: f5c1434c217f ("irqchip: GICv3: rework redistributor structure")
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Back in the days when the GICv3/v4 architecture was drafted,
the command to an event to an LPI number was called MAPVI.
Later on, and to avoid confusion with the GICv4 command VMAPI,
it was renamed MAPTI. We've carried the old name for a long
time, but it gets in the way of people reading the code in
the light of the public architecture specification.
Just repaint all the references and kill the old definition.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Commit 17ce039b4e54 ("[media] cxusb: don't do DMA on stack")
added a kmalloc'ed bounce buffer for writes, but missed to do the same
for reads. As the read only happens after the write is finished, we can
reuse the same buffer.
As dvb_usb_generic_rw handles a read length of 0 by itself, avoid calling
it using the dvb_usb_generic_read wrapper function.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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During the development of the GICv3/v4 architecture, it was
envisaged to have a CPU table, though the use for it was
never completely clear (the collection table serves that role
pretty well). It ended being dropped before the specification
was published, though it lived on in the driver.
In order to avoid people scratching their head too much, let's do
the same in the kernel.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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The way we encode the various ITS command fields is both tedious
and error prone. Let's introduce a helper function that performs
the encoding, and convert the existing encoders to use that
helper. It also has the advantage of expressing the encoding in
a way that matches the architecture specification.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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gcc-7.0.1 warns about old code in ttpci:
In file included from drivers/media/pci/ttpci/av7110.c:63:0:
In function 'irdebi.isra.2',
inlined from 'start_debi_dma' at drivers/media/pci/ttpci/av7110.c:376:3,
inlined from 'gpioirq' at drivers/media/pci/ttpci/av7110.c:659:3:
drivers/media/pci/ttpci/av7110_hw.h:406:3: warning: 'memcpy': specified size between 18446744071562067968 and 18446744073709551615 exceeds maximum object size 9223372036854775807 [-Wstringop-overflow=]
memcpy(av7110->debi_virt, (char *) &res, count);
In function 'irdebi.isra.2',
inlined from 'start_debi_dma' at drivers/media/pci/ttpci/av7110.c:376:3,
inlined from 'gpioirq' at drivers/media/pci/ttpci/av7110.c:668:3:
drivers/media/pci/ttpci/av7110_hw.h:406:3: warning: 'memcpy': specified size between 18446744071562067968 and 18446744073709551615 exceeds maximum object size 9223372036854775807 [-Wstringop-overflow=]
memcpy(av7110->debi_virt, (char *) &res, count);
Apparently, 'count' can be negative here, which will then get turned
into a giant size argument for memcpy. Changing the sizes to 'unsigned
int' instead seems safe as we already check for maximum sizes, and it
also simplifies the code a bit.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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I ran into a stack frame size warning because of the on-stack copy of
the USB device structure:
drivers/media/usb/dvb-usb-v2/dvb_usb_core.c: In function 'dvb_usbv2_disconnect':
drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:1029:1: error: the frame size of 1104 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
Copying a device structure like this is wrong for a number of other reasons
too aside from the possible stack overflow. One of them is that the
dev_info() call will print the name of the device later, but AFAICT
we have only copied a pointer to the name earlier and the actual name
has been freed by the time it gets printed.
This removes the on-stack copy of the device and instead copies the
device name using kstrdup(). I'm ignoring the possible failure here
as both printk() and kfree() are able to deal with NULL pointers.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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Read-allocation hints are not enabled for both the GIC-ITS and GICR
tables. This forces the hardware to always read the table contents
from an external memory (DDR) which is slow compared to cache memory.
Most of the tables are often read by hardware. So, it's better to
enable Read-allocate hints in addition to Write-allocate hints in
order to improve the GICR_PEND, GICR_PROP, Collection, Device, and
vCPU tables lookup time.
Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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The dynamic-list-file used to export dynamic symbols introduced in
commit e3d09ec8126f ("tools lib traceevent: Export dynamic symbols
used by traceevent plugins")
is generated without any sort of error checking.
I experienced problems due to an old version of nm (v 0.158) that outputs
in a format distinct from the assumed by the script.
Robustify the built of dynamic symbol list by enforcing that the second
column of $(NM) -u <files> is either "U" (Undefined), "W" or "w" (undefined
weak), which are the possible outputs from non-ancient $(NM) versions.
Print an error if format is unexpected.
v2: Accept "W" and "w" symbol options.
Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170208052840.112182-1-davidcc@google.com
[ Use STRING1 = STRING1 instead of == to make this work on Ubuntu systems ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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This patch implements the kernel side of the TCP option patch.
Signed-off-by: Manuel Messner <mm@skelett.io>
Reviewed-by: Florian Westphal <fw@strlen.de>
Acked-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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zones allow tracking multiple connections sharing identical tuples,
this is needed e.g. when tracking distinct vlans with overlapping ip
addresses (conntrack is l2 agnostic).
Thus the zone has to be set before the packet is picked up by the
connection tracker. This is done by means of 'conntrack templates' which
are conntrack structures used solely to pass this info from one netfilter
hook to the next.
The iptables CT target instantiates these connection tracking templates
once per rule, i.e. the template is fixed/tied to particular zone, can
be read-only and therefore be re-used by as many skbs simultaneously as
needed.
We can't follow this model because we want to take the zone id from
an sreg at rule eval time so we could e.g. fill in the zone id from
the packets vlan id or a e.g. nftables key : value maps.
To avoid cost of per packet alloc/free of the template, use a percpu
template 'scratch' object and use the refcount to detect the (unlikely)
case where the template is still attached to another skb (i.e., previous
skb was nfqueued ...).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Next patch will add ZONE_ID set support which will need similar
error unwind (put operation) as conntrack labels.
Prepare for this: remove the 'label_got' boolean in favor
of a switch statement that can be extended in next patch.
As we already have that in the set_destroy function place that in
a separate function and call it from the set init function.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Just like with counters the direction attribute is optional.
We set priv->dir to MAX unconditionally to avoid duplicating the assignment
for all keys with optional direction.
For keys where direction is mandatory, existing code already returns
an error.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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This patch adds a new bitmap set type. This bitmap uses two bits to
represent one element. These two bits determine the element state in the
current and the future generation that fits into the nf_tables commit
protocol. When dumping elements back to userspace, the two bits are
expanded into a struct nft_set_ext object.
If no NFTA_SET_DESC_SIZE is specified, the existing automatic set
backend selection prefers bitmap over hash in case of keys whose size is
<= 16 bit. If the set size is know, the bitmap set type is selected if
with 16 bit kets and more than 390 elements in the set, otherwise the
hash table set implementation is used.
For 8 bit keys, the bitmap consumes 66 bytes. For 16 bit keys, the
bitmap takes 16388 bytes.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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The space notation allows us to classify the set backend implementation
based on the amount of required memory. This provides an order of the
set representation scalability in terms of memory. The size field is
still left in place so use this if the userspace provides no explicit
number of elements, so we cannot calculate the real memory that this set
needs. This also helps us break ties in the set backend selection
routine, eg. two backend implementations provide the same performance.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Use lookup as field name instead, to prepare the introduction of the
memory class in a follow up patch.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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This provides context to walk callback iterator, thus, we know if the
walk happens from the set flush path. This is required by the new bitmap
set type coming in a follow up patch which has no real struct
nft_set_ext, so it has to allocate it based on the two bit compact
element representation.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Although semantics are similar to deactivate() with no implicit element
lookup, this is only called from the set flush path, so better rename
this to flush().
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Instead of struct nft_set_dump_args, remove unnecessary wrapper
structure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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This new parameter is required by the new bitmap set type that comes in a
follow up patch.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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If NFT_EXTHDR_F_PRESENT is set, exthdr will not copy any header field
data into *dest, but instead set it to 1 if the header is found and 0
otherwise.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Bit 0x100 of a page table, segment table of region table entry
can be used to disallow code execution for the virtual addresses
associated with the entry.
There is one tricky bit, the system call to return from a signal
is part of the signal frame written to the user stack. With a
non-executable stack this would stop working. To avoid breaking
things the protection fault handler checks the opcode that caused
the fault for 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn)
and injects a system call. This is preferable to the alternative
solution with a stub function in the vdso because it works for
vdso=off and statically linked binaries as well.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Add hardware capability bits and feature tags to /proc/cpuinfo for
the "Vector Packed Decimal Facility" (tag "vxd" / hwcap bit 2^12)
and the "Vector Enhancements Facility 1" (tag "vxe" / hwcap bit 2^13).
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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The current implementation of setup_randomness uses the stack address
and therefore the pointer to the SYSIB 3.2.2 block as input data
address. Furthermore the length of the input data is the number of
virtual-machine description blocks which is typically one.
This means that typically a single zero byte is fed to
add_device_randomness.
Fix both of these and use the address of the first virtual machine
description block as input data address and also use the correct
length.
Fixes: bcfcbb6bae64 ("s390: add system information as device randomness")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Get rid of common response code handling. Each command requires its
own response code handling anyway. Also the retry in case of -EBUSY
does not work and can be simply removed.
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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The early vt220 sclp printk code added an extra new line to each
printed multi-line text. If used for the early sclp console this will
lead to numerous extra new lines. Therefore get rid of this semantic
and require that each to be printed string contains a line feed
character if a new line is wanted.
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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This patch
- unifies the old sclp early code and the sclp early printk code, so
they can use common functions
- makes sure all sclp early functions and variables have the same
"sclp_early" prefix
- converts the sclp early printk code into readable code by using
existing data structures instead of hard coded magic arrays
- splits the early sclp code into two files: sclp_early.c and
sclp_early_core.c. The core file contains everything that is
required by the kernel decompressor and may not call functions not
contained within the core file. Otherwise the result would be a
link error.
- changes interrupt handling to be completely synchronous. The old
early sclp code had a small window which allowed to receive several
interrupts instead of exactly the single expected interrupt. This
did hide a subtle potential bug, which is fixed with this large
rework.
- contains a couple of small cleanups.
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Make sure the early sclp code does not generate any sclp requests
anymore as soon as the base sclp driver is active. Otherwise both
drivers may see unexpected requests or may miss expected interrupts.
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Move the early sclp printk code to the drivers folder where also the
rest of the sclp code can be found. This way it is possible to use the
sclp private header files for further cleanups.
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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We do suppress_message_printing() check before we call
call_console_drivers() now, so `level' param is not needed
anymore.
Link: http://lkml.kernel.org/r/20161224140902.1962-2-sergey.senozhatsky@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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This patch converts the rest of logbuf users (which are
out of printk recursion case, but can deadlock in printk).
To make printk-safe usage easier the patch introduces 4
helper macros:
- logbuf_lock_irq()/logbuf_unlock_irq()
lock/unlock the logbuf lock and disable/enable local IRQ
- logbuf_lock_irqsave(flags)/logbuf_unlock_irqrestore(flags)
lock/unlock the logbuf lock and saves/restores local IRQ state
Link: http://lkml.kernel.org/r/20161227141611.940-9-sergey.senozhatsky@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Calvin Owens <calvinowens@fb.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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Adding Hama Hybrid DVB-T Stick support. Technically it's the same
device what Terratec Cinergy HT USB XE is.
Signed-off-by: Piotr Oleszczyk <piotr.oleszczyk@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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We use printk-safe now which makes printk-recursion detection code
in vprintk_emit() unreachable. The tricky thing here is that, apart
from detecting and reporting printk recursions, that code also used
to zap_locks() in case of panic() from the same CPU. However,
zap_locks() does not look to be needed anymore:
1) Since commit 08d78658f393 ("panic: release stale console lock to
always get the logbuf printed out") panic flushing of `logbuf' to
console ignores the state of `console_sem' by doing
panic()
console_trylock();
console_unlock();
2) Since commit cf9b1106c81c ("printk/nmi: flush NMI messages on the
system panic") panic attempts to zap the `logbuf_lock' spin_lock to
successfully flush nmi messages to `logbuf'.
Basically, it seems that we either already do what zap_locks() used to
do but in other places or we ignore the state of the lock. The only
reaming difference is that we don't re-init the console semaphore in
printk_safe_flush_on_panic(), but this is not necessary because we
don't call console drivers from printk_safe_flush_on_panic() due to
the fact that we are using a deferred printk() version (as was
suggested by Petr Mladek).
Link: http://lkml.kernel.org/r/20161227141611.940-8-sergey.senozhatsky@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Calvin Owens <calvinowens@fb.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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Use printk_safe per-CPU buffers in printk recursion-prone blocks:
-- around logbuf_lock protected sections in vprintk_emit() and
console_unlock()
-- around down_trylock_console_sem() and up_console_sem()
Note that this solution addresses deadlocks caused by printk()
recursive calls only. That is vprintk_emit() and console_unlock().
The rest will be converted in a followup patch.
Another thing to note is that we now keep lockdep enabled in printk,
because we are protected against the printk recursion caused by
lockdep in vprintk_emit() by the printk-safe mechanism - we first
switch to per-CPU buffers and only then access the deadlock-prone
locks.
Examples:
1) printk() from logbuf_lock spin_lock section
Assume the following code:
printk()
raw_spin_lock(&logbuf_lock);
WARN_ON(1);
raw_spin_unlock(&logbuf_lock);
which now produces:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 366 at kernel/printk/printk.c:1811 vprintk_emit
CPU: 0 PID: 366 Comm: bash
Call Trace:
warn_slowpath_null+0x1d/0x1f
vprintk_emit+0x1cd/0x438
vprintk_default+0x1d/0x1f
printk+0x48/0x50
[..]
2) printk() from semaphore sem->lock spin_lock section
Assume the following code
printk()
console_trylock()
down_trylock()
raw_spin_lock_irqsave(&sem->lock, flags);
WARN_ON(1);
raw_spin_unlock_irqrestore(&sem->lock, flags);
which now produces:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 363 at kernel/locking/semaphore.c:141 down_trylock
CPU: 1 PID: 363 Comm: bash
Call Trace:
warn_slowpath_null+0x1d/0x1f
down_trylock+0x3d/0x62
? vprintk_emit+0x3f9/0x414
console_trylock+0x31/0xeb
vprintk_emit+0x3f9/0x414
vprintk_default+0x1d/0x1f
printk+0x48/0x50
[..]
3) printk() from console_unlock()
Assume the following code:
printk()
console_unlock()
raw_spin_lock(&logbuf_lock);
WARN_ON(1);
raw_spin_unlock(&logbuf_lock);
which now produces:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 329 at kernel/printk/printk.c:2384 console_unlock
CPU: 1 PID: 329 Comm: bash
Call Trace:
warn_slowpath_null+0x18/0x1a
console_unlock+0x12d/0x559
? trace_hardirqs_on_caller+0x16d/0x189
? trace_hardirqs_on+0xd/0xf
vprintk_emit+0x363/0x374
vprintk_default+0x18/0x1a
printk+0x43/0x4b
[..]
4) printk() from try_to_wake_up()
Assume the following code:
printk()
console_unlock()
up()
try_to_wake_up()
raw_spin_lock_irqsave(&p->pi_lock, flags);
WARN_ON(1);
raw_spin_unlock_irqrestore(&p->pi_lock, flags);
which now produces:
------------[ cut here ]------------
WARNING: CPU: 3 PID: 363 at kernel/sched/core.c:2028 try_to_wake_up
CPU: 3 PID: 363 Comm: bash
Call Trace:
warn_slowpath_null+0x1d/0x1f
try_to_wake_up+0x7f/0x4f7
wake_up_process+0x15/0x17
__up.isra.0+0x56/0x63
up+0x32/0x42
__up_console_sem+0x37/0x55
console_unlock+0x21e/0x4c2
vprintk_emit+0x41c/0x462
vprintk_default+0x1d/0x1f
printk+0x48/0x50
[..]
5) printk() from call_console_drivers()
Assume the following code:
printk()
console_unlock()
call_console_drivers()
...
WARN_ON(1);
which now produces:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 305 at kernel/printk/printk.c:1604 call_console_drivers
CPU: 2 PID: 305 Comm: bash
Call Trace:
warn_slowpath_null+0x18/0x1a
call_console_drivers.isra.6.constprop.16+0x3a/0xb0
console_unlock+0x471/0x48e
vprintk_emit+0x1f4/0x206
vprintk_default+0x18/0x1a
vprintk_func+0x6e/0x70
printk+0x3e/0x46
[..]
6) unsupported placeholder in printk() format now prints an actual
warning from vscnprintf(), instead of
'BUG: recent printk recursion!'.
------------[ cut here ]------------
WARNING: CPU: 5 PID: 337 at lib/vsprintf.c:1900 format_decode
Please remove unsupported %
in format string
CPU: 5 PID: 337 Comm: bash
Call Trace:
dump_stack+0x4f/0x65
__warn+0xc2/0xdd
warn_slowpath_fmt+0x4b/0x53
format_decode+0x22c/0x308
vsnprintf+0x89/0x3b7
vscnprintf+0xd/0x26
vprintk_emit+0xb4/0x238
vprintk_default+0x1d/0x1f
vprintk_func+0x6c/0x73
printk+0x43/0x4b
[..]
Link: http://lkml.kernel.org/r/20161227141611.940-7-sergey.senozhatsky@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Calvin Owens <calvinowens@fb.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Account lost messages in pritk-safe and printk-safe-nmi
contexts and report those numbers during printk_safe_flush().
The patch also moves lost message counter to struct
`printk_safe_seq_buf' instead of having dedicated static
counters - this simplifies the code.
Link: http://lkml.kernel.org/r/20161227141611.940-6-sergey.senozhatsky@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Calvin Owens <calvinowens@fb.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
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The cases changed in this patch are for when we free but keep the
pointer to the freed area, which is not always a good idea.
Be more defensive and zero the pointer to avoid possible use after
free bugs to take more time to be detected.
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1485952447-7013-5-git-send-email-treeze.taeung@gmail.com
[ rewrote commit log ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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We have zfree(&ptr) for this very common pattern:
free(ptr);
ptr = NULL;
So use it in a few more places.
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1485952447-7013-4-git-send-email-treeze.taeung@gmail.com
[ rewrote commit log ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1485952447-7013-3-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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