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Given we'll be reusing BPF array maps for global data/bss/rodata
sections, we need a way to associate BTF DataSec type as its map
value type. In usual cases we have this ugly BPF_ANNOTATE_KV_PAIR()
macro hack e.g. via 38d5d3b3d5db ("bpf: Introduce BPF_ANNOTATE_KV_PAIR")
to get initial map to type association going. While more use cases
for it are discouraged, this also won't work for global data since
the use of array map is a BPF loader detail and therefore unknown
at compilation time. For array maps with just a single entry we make
an exception in terms of BTF in that key type is declared optional
if value type is of DataSec type. The latter LLVM is guaranteed to
emit and it also aligns with how we regard global data maps as just
a plain buffer area reusing existing map facilities for allowing
things like introspection with existing tools.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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This patch adds a new BPF_MAP_FREEZE command which allows to
"freeze" the map globally as read-only / immutable from syscall
side.
Map permission handling has been refactored into map_get_sys_perms()
and drops FMODE_CAN_WRITE in case of locked map. Main use case is
to allow for setting up .rodata sections from the BPF ELF which
are loaded into the kernel, meaning BPF loader first allocates
map, sets up map value by copying .rodata section into it and once
complete, it calls BPF_MAP_FREEZE on the map fd to prevent further
modifications.
Right now BPF_MAP_FREEZE only takes map fd as argument while remaining
bpf_attr members are required to be zero. I didn't add write-only
locking here as counterpart since I don't have a concrete use-case
for it on my side, and I think it makes probably more sense to wait
once there is actually one. In that case bpf_attr can be extended
as usual with a flag field and/or others where flag 0 means that
we lock the map read-only hence this doesn't prevent to add further
extensions to BPF_MAP_FREEZE upon need.
A map creation flag like BPF_F_WRONCE was not considered for couple
of reasons: i) in case of a generic implementation, a map can consist
of more than just one element, thus there could be multiple map
updates needed to set the map into a state where it can then be
made immutable, ii) WRONCE indicates exact one-time write before
it is then set immutable. A generic implementation would set a bit
atomically on map update entry (if unset), indicating that every
subsequent update from then onwards will need to bail out there.
However, map updates can fail, so upon failure that flag would need
to be unset again and the update attempt would need to be repeated
for it to be eventually made immutable. While this can be made
race-free, this approach feels less clean and in combination with
reason i), it's not generic enough. A dedicated BPF_MAP_FREEZE
command directly sets the flag and caller has the guarantee that
map is immutable from syscall side upon successful return for any
future syscall invocations that would alter the map state, which
is also more intuitive from an API point of view. A command name
such as BPF_MAP_LOCK has been avoided as it's too close with BPF
map spin locks (which already has BPF_F_LOCK flag). BPF_MAP_FREEZE
is so far only enabled for privileged users.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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This work adds two new map creation flags BPF_F_RDONLY_PROG
and BPF_F_WRONLY_PROG in order to allow for read-only or
write-only BPF maps from a BPF program side.
Today we have BPF_F_RDONLY and BPF_F_WRONLY, but this only
applies to system call side, meaning the BPF program has full
read/write access to the map as usual while bpf(2) calls with
map fd can either only read or write into the map depending
on the flags. BPF_F_RDONLY_PROG and BPF_F_WRONLY_PROG allows
for the exact opposite such that verifier is going to reject
program loads if write into a read-only map or a read into a
write-only map is detected. For read-only map case also some
helpers are forbidden for programs that would alter the map
state such as map deletion, update, etc. As opposed to the two
BPF_F_RDONLY / BPF_F_WRONLY flags, BPF_F_RDONLY_PROG as well
as BPF_F_WRONLY_PROG really do correspond to the map lifetime.
We've enabled this generic map extension to various non-special
maps holding normal user data: array, hash, lru, lpm, local
storage, queue and stack. Further generic map types could be
followed up in future depending on use-case. Main use case
here is to forbid writes into .rodata map values from verifier
side.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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This generic extension to BPF maps allows for directly loading
an address residing inside a BPF map value as a single BPF
ldimm64 instruction!
The idea is similar to what BPF_PSEUDO_MAP_FD does today, which
is a special src_reg flag for ldimm64 instruction that indicates
that inside the first part of the double insns's imm field is a
file descriptor which the verifier then replaces as a full 64bit
address of the map into both imm parts. For the newly added
BPF_PSEUDO_MAP_VALUE src_reg flag, the idea is the following:
the first part of the double insns's imm field is again a file
descriptor corresponding to the map, and the second part of the
imm field is an offset into the value. The verifier will then
replace both imm parts with an address that points into the BPF
map value at the given value offset for maps that support this
operation. Currently supported is array map with single entry.
It is possible to support more than just single map element by
reusing both 16bit off fields of the insns as a map index, so
full array map lookup could be expressed that way. It hasn't
been implemented here due to lack of concrete use case, but
could easily be done so in future in a compatible way, since
both off fields right now have to be 0 and would correctly
denote a map index 0.
The BPF_PSEUDO_MAP_VALUE is a distinct flag as otherwise with
BPF_PSEUDO_MAP_FD we could not differ offset 0 between load of
map pointer versus load of map's value at offset 0, and changing
BPF_PSEUDO_MAP_FD's encoding into off by one to differ between
regular map pointer and map value pointer would add unnecessary
complexity and increases barrier for debugability thus less
suitable. Using the second part of the imm field as an offset
into the value does /not/ come with limitations since maximum
possible value size is in u32 universe anyway.
This optimization allows for efficiently retrieving an address
to a map value memory area without having to issue a helper call
which needs to prepare registers according to calling convention,
etc, without needing the extra NULL test, and without having to
add the offset in an additional instruction to the value base
pointer. The verifier then treats the destination register as
PTR_TO_MAP_VALUE with constant reg->off from the user passed
offset from the second imm field, and guarantees that this is
within bounds of the map value. Any subsequent operations are
normally treated as typical map value handling without anything
extra needed from verification side.
The two map operations for direct value access have been added to
array map for now. In future other types could be supported as
well depending on the use case. The main use case for this commit
is to allow for BPF loader support for global variables that
reside in .data/.rodata/.bss sections such that we can directly
load the address of them with minimal additional infrastructure
required. Loader support has been added in subsequent commits for
libbpf library.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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No modular uses since introducion of alloc_file_pseudo(),
and the only non-modular user not in alloc_file_pseudo()
had actually been wrong - should've been d_alloc_anon().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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For lockless accesses to dentries we don't have pinned we rely
(among other things) upon having an RCU delay between dropping
the last reference and actually freeing the memory.
On the other hand, for things like pipes and sockets we neither
do that kind of lockless access, nor want to deal with the
overhead of an RCU delay every time a socket gets closed.
So delay was made optional - setting DCACHE_RCUACCESS in ->d_flags
made sure it would happen. We tried to avoid setting it unless
we knew we need it. Unfortunately, that had led to recurring
class of bugs, in which we missed the need to set it.
We only really need it for dentries that are created by
d_alloc_pseudo(), so let's not bother with trying to be smart -
just make having an RCU delay the default. The ones that do
*not* get it set the replacement flag (DCACHE_NORCU) and we'd
better use that sparingly. d_alloc_pseudo() is the only
such user right now.
FWIW, the race that finally prompted that switch had been
between __lock_parent() of immediate subdirectory of what's
currently the root of a disconnected tree (e.g. from
open-by-handle in progress) racing with d_splice_alias()
elsewhere picking another alias for the same inode, either
on outright corrupted fs image, or (in case of open-by-handle
on NFS) that subdirectory having been just moved on server.
It's not easy to hit, so the sky is not falling, but that's
not the first race on similar missed cases and the logics
for settinf DCACHE_RCUACCESS has gotten ridiculously
convoluted.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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To be able to predict the sleep duration for a CPU entering idle, it
is essential to know the expiration time of the next timer. Both the
teo and the menu cpuidle governors already use this information for
CPU idle state selection.
Moving forward, a similar prediction needs to be made for a group of
idle CPUs rather than for a single one and the following changes
implement a new genpd governor for that purpose.
In order to support that feature, add a new function called
tick_nohz_get_next_hrtimer() that will return the next hrtimer
expiration time of a given CPU to be invoked after deciding
whether or not to stop the scheduler tick on that CPU.
Make the cpuidle core call tick_nohz_get_next_hrtimer() right
before invoking the ->enter() callback provided by the cpuidle
driver for the given state and store its return value in the
per-CPU struct cpuidle_device, so as to make it available to code
outside of cpuidle.
Note that at the point when cpuidle calls tick_nohz_get_next_hrtimer(),
the governor's ->select() callback has already returned and indicated
whether or not the tick should be stopped, so in fact the value
returned by tick_nohz_get_next_hrtimer() always is the next hrtimer
expiration time for the given CPU, possibly including the tick (if
it hasn't been stopped).
Co-developed-by: Lina Iyer <lina.iyer@linaro.org>
Co-developed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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To enable a CPU device to be attached to a PM domain managed by genpd,
make a few changes to it for convenience.
To be able to quickly find out what CPUs are attached to a genpd,
which typically becomes useful from a genpd governor as subsequent
changes are about to show, add a cpumask to struct generic_pm_domain
to be updated when a CPU device gets attached to the genpd containing
that cpumask. Also, propagate the cpumask changes upwards in the
domain hierarchy to the master PM domains. This way, the cpumask for
a genpd hierarchically reflects all CPUs attached to the topology
below it.
Finally, make this an opt-in feature, to avoid having to manage CPUs
and the cpumask for a genpd that don't need it. To that end, add
a new genpd configuration bit, GENPD_FLAG_CPU_DOMAIN.
Co-developed-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Add a data pointer to the genpd_power_state struct, to allow a genpd
backend driver to store per-state specific data. To introduce the
pointer, change the way genpd deals with freeing of the corresponding
allocated data.
More precisely, clarify the responsibility of whom that shall free the
data, by adding a ->free_states() callback to the generic_pm_domain
structure. The one allocating the data will be expected to set the
callback, to allow genpd to invoke it from genpd_remove().
Co-developed-by: Lina Iyer <lina.iyer@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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'fixes.2019.03.26b', 'srcu.2019.03.26b', 'stall.2019.03.26b' and 'torture.2019.03.26b' into HEAD
consolidate.2019.04.09a: Lingering RCU flavor consolidation cleanups.
doc.2019.03.26b: Documentation updates.
fixes.2019.03.26b: Miscellaneous fixes.
srcu.2019.03.26b: SRCU updates.
stall.2019.03.26b: RCU CPU stall warning updates.
torture.2019.03.26b: Torture-test updates.
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We have a function to copy strings safely and we have a function to copy
strings and zero the tail of the destination (if source string is
shorter than destination buffer) but we do not have a function to do
both at once. This means developers must write this themselves if they
desire this functionality. This is a chore, and also leaves us open to
off by one errors unnecessarily.
Add a function that calls strscpy() then memset()s the tail to zero if
the source string is shorter than the destination buffer.
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>
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genphy_read_status() so far checks phydev->supported, not the actual
PHY capabilities. This can make a difference if the supported speeds
have been limited by of_set_phy_supported() or phy_set_max_speed().
It seems that this issue only affects the link partner advertisements
as displayed by ethtool. Also this patch wouldn't apply to older
kernels because linkmode bitmaps have been introduced recently.
Therefore net-next.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux
Saeed Mamameed says:
====================
mlx5-updates-2019-04-02
This series provides misc updates to mlx5 driver
1) Aya Levin (1): Handle event of power detection in the PCIE slot
2) Eli Britstein (6):
Some TC VLAN related updates and fixes to the previous VLAN modify action
support patchset.
Offload TC e-switch rules with egress/ingress VLAN devices
3) Max Gurtovoy (1): Fix double mutex initialization in esiwtch.c
4) Tariq Toukan (3): Misc small updates
A write memory barrier is sufficient in EQ ci update
Obsolete param field holding a constant value
Unify logic of MTU boundaries
5) Tonghao Zhang (4): Misc updates to en_tc.c
Make the log friendly when decapsulation offload not supported
Remove 'parse_attr' argument in parse_tc_fdb_actions()
Deletes unnecessary setting of esw_attr->parse_attr
Return -EOPNOTSUPP when attempting to offload an unsupported action
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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They have no external callers anymore.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Add version option support to the nftables "osf" expression.
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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vring_create_virtqueue() allows the caller to specify via the
may_reduce_num parameter whether the vring code is allowed to
allocate a smaller ring than specified.
However, the split ring allocation code tries to allocate a
smaller ring on allocation failure regardless of what the
caller specified. This may cause trouble for e.g. virtio-pci
in legacy mode, which does not support ring resizing. (The
packed ring code does not resize in any case.)
Let's fix this by bailing out immediately in the split ring code
if the requested size cannot be allocated and may_reduce_num has
not been specified.
While at it, fix a typo in the usage instructions.
Fixes: 2a2d1382fe9d ("virtio: Add improved queue allocation API")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
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NF_NAT_NEEDED is true whenever nat support for either ipv4 or ipv6 is
enabled. Now that the af-specific nat configuration switches have been
removed, IS_ENABLED(CONFIG_NF_NAT) has the same effect.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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very little code, so it really doesn't make sense to have extra
modules or even a kconfig knob for this.
Merge them and make functionality available unconditionally.
The merge makes inet family route support trivial, so add it
as well here.
Before:
text data bss dec hex filename
835 832 0 1667 683 nft_chain_route_ipv4.ko
870 832 0 1702 6a6 nft_chain_route_ipv6.ko
111568 2556 529 114653 1bfdd nf_tables.ko
After:
text data bss dec hex filename
113133 2556 529 116218 1c5fa nf_tables.ko
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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optimize nf_inet_addr_cmp by 64bit xor computation
similar to ipv6_addr_equal()
Signed-off-by: Yuan Linsi <yuanlinsi01@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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there is a similar helper in net/netfilter/nf_tables_api.c,
this maybe become a common request someday, so move it to
time.c
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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After commit a297569fe00a ("net/udp: do not touch skb->peeked unless
really needed") the 'peeked' argument of __skb_try_recv_datagram()
and friends is always equal to !!'flags & MSG_PEEK'.
Since such argument is really a boolean info, and the callers have
already 'flags & MSG_PEEK' handy, we can remove it and clean-up the
code a bit.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit 6dc4f100c175 ("block: allow bio_for_each_segment_all() to
iterate over multi-page bvec") changes bio_for_each_segment_all()
to use for-inside-for.
This way breaks all bio_for_each_segment_all() call with error out
branch via 'break', since now 'break' can only break from the inner
loop.
Fixes this issue by implementing bio_for_each_segment_all() via
single 'for' loop, and now the logic is very similar with normal
bvec iterator.
Cc: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: linux-btrfs@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: Omar Sandoval <osandov@fb.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-and-Tested-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Fixes: 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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mmiowb() is now implied by spin_unlock() on architectures that require
it, so there is no reason to call it from driver code. This patch was
generated using coccinelle:
@mmiowb@
@@
- mmiowb();
and invoked as:
$ for d in drivers include/linux/qed sound; do \
spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done
NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation. If you've ended up bisecting to this commit, you can
reintroduce the mmiowb() calls using wmb() instead, which should restore
the old behaviour on all architectures other than some esoteric ia64
systems.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
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Removing explicit calls to mmiowb() from driver code means that we must
now call into the generic mmiowb_spin_{lock,unlock}() functions from the
core spinlock code. In order to elide barriers following critical
sections without any I/O writes, we also hook into the asm-generic I/O
routines.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
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While the cpuinfo.max_freq value doesn't really matter for
intel_pstate in the active mode, in the passive mode it is used by
governors as the maximum physical frequency of the CPU and the
results of governor computations generally depend on it. Also it
is made available to user space via sysfs and it should match the
current HW configuration.
For this reason, make intel_pstate update cpuinfo.max_freq for all
CPUs if it detects a global change of turbo frequency settings from
"disable" to "enable" or the other way associated with a _PPC change
notification from the platform firmware.
Note that policy_is_inactive(), cpufreq_cpu_acquire(),
cpufreq_cpu_release(), and cpufreq_set_policy() need to be made
available to it for this purpose.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759
Reported-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
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This patch creates set_cs_timing SPI master optional method for
SPI masters to implement configuring CS timing if applicable.
This patch also creates spi_cs_timing accessory for SPI clients to
use for requesting SPI master controllers to configure device requested
CS setup time, hold time and inactive delay.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
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Move all of the code doing struct spi_bitbang initialization, so that
it can be paired with devm_spi_register_master() in order to avoid
having to call spi_bitbang_stop() explicitly.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-spi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
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The current definition and implementation of the SEV_GET_ID command
does not provide the length of the unique ID returned by the firmware.
As per the firmware specification, the firmware may return an ID
length that is not restricted to 64 bytes as assumed by the SEV_GET_ID
command.
Introduce the SEV_GET_ID2 command to overcome with the SEV_GET_ID
limitations. Deprecate the SEV_GET_ID in the favor of SEV_GET_ID2.
At the same time update SEV API web link.
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Nathaniel McCallum <npmccallum@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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Native bit_spin_locks are not tracked by lockdep.
The bit_spin_locks used for rhashtable buckets are local
to the rhashtable implementation, so there is little opportunity
for the sort of misuse that lockdep might detect.
However locks are held while a hash function or compare
function is called, and if one of these took a lock,
a misbehaviour is possible.
As it is quite easy to add lockdep support this unlikely
possibility seems to be enough justification.
So create a lockdep class for bucket bit_spin_lock and attach
through a lockdep_map in each bucket_table.
Without the 'nested' annotation in rhashtable_rehash_one(), lockdep
correctly reports a possible problem as this lock is taken
while another bucket lock (in another table) is held. This
confirms that the added support works.
With the correct nested annotation in place, lockdep reports
no problems.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch changes rhashtables to use a bit_spin_lock on BIT(1) of the
bucket pointer to lock the hash chain for that bucket.
The benefits of a bit spin_lock are:
- no need to allocate a separate array of locks.
- no need to have a configuration option to guide the
choice of the size of this array
- locking cost is often a single test-and-set in a cache line
that will have to be loaded anyway. When inserting at, or removing
from, the head of the chain, the unlock is free - writing the new
address in the bucket head implicitly clears the lock bit.
For __rhashtable_insert_fast() we ensure this always happens
when adding a new key.
- even when lockings costs 2 updates (lock and unlock), they are
in a cacheline that needs to be read anyway.
The cost of using a bit spin_lock is a little bit of code complexity,
which I think is quite manageable.
Bit spin_locks are sometimes inappropriate because they are not fair -
if multiple CPUs repeatedly contend of the same lock, one CPU can
easily be starved. This is not a credible situation with rhashtable.
Multiple CPUs may want to repeatedly add or remove objects, but they
will typically do so at different buckets, so they will attempt to
acquire different locks.
As we have more bit-locks than we previously had spinlocks (by at
least a factor of two) we can expect slightly less contention to
go with the slightly better cache behavior and reduced memory
consumption.
To enhance type checking, a new struct is introduced to represent the
pointer plus lock-bit
that is stored in the bucket-table. This is "struct rhash_lock_head"
and is empty. A pointer to this needs to be cast to either an
unsigned lock, or a "struct rhash_head *" to be useful.
Variables of this type are most often called "bkt".
Previously "pprev" would sometimes point to a bucket, and sometimes a
->next pointer in an rhash_head. As these are now different types,
pprev is NULL when it would have pointed to the bucket. In that case,
'blk' is used, together with correct locking protocol.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Rather than returning a pointer to a static nulls, rht_bucket_var()
now returns NULL if the bucket doesn't exist.
This will make the next patch, which stores a bitlock in the
bucket pointer, somewhat cleaner.
This change involves introducing __rht_bucket_nested() which is
like rht_bucket_nested(), but doesn't provide the static nulls,
and changing rht_bucket_nested() to call this and possible
provide a static nulls - as is still needed for the non-var case.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
The current handling of MSR_IA32_ENERGY_PERF_BIAS in the kernel is
problematic, because it may cause changes made by user space to that
MSR (with the help of the x86_energy_perf_policy tool, for example)
to be lost every time a CPU goes offline and then back online as well
as during system-wide power management transitions into sleep states
and back into the working state.
The first problem is that if the current EPB value for a CPU going
online is 0 ('performance'), the kernel will change it to 6 ('normal')
regardless of whether or not this is the first bring-up of that CPU.
That also happens during system-wide resume from sleep states
(including, but not limited to, hibernation). However, the EPB may
have been adjusted by user space this way and the kernel should not
blindly override that setting.
The second problem is that if the platform firmware resets the EPB
values for any CPUs during system-wide resume from a sleep state,
the kernel will not restore their previous EPB values that may
have been set by user space before the preceding system-wide
suspend transition. Again, that behavior may at least be confusing
from the user space perspective.
In order to address these issues, rework the handling of
MSR_IA32_ENERGY_PERF_BIAS so that the EPB value is saved on CPU
offline and restored on CPU online as well as (for the boot CPU)
during the syscore stages of system-wide suspend and resume
transitions, respectively.
However, retain the policy by which the EPB is set to 6 ('normal')
on the first bring-up of each CPU if its initial value is 0, based
on the observation that 0 may mean 'not initialized' just as well as
'performance' in that case.
While at it, move the MSR_IA32_ENERGY_PERF_BIAS handling code into
a separate file and document it in Documentation/admin-guide.
Fixes: abe48b108247 (x86, intel, power: Initialize MSR_IA32_ENERGY_PERF_BIAS)
Fixes: b51ef52df71c (x86/cpu: Restore MSR_IA32_ENERGY_PERF_BIAS after resume)
Reported-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
|
|
Remove the LM3532 backlight driver references from the ti-lmu
code as dedicated driver support is available.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
|
|
run simultaneously without deadlock
Commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.
This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.
The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.
However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655e3 -
is doing so irregardless of whether a file is seekable or not.
See
https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/
https://lwn.net/Articles/180387
https://lwn.net/Articles/180396
for historic context.
The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:
kernel/power/user.c snapshot_read
fs/debugfs/file.c u32_array_read
fs/fuse/control.c fuse_conn_waiting_read + ...
drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read
arch/s390/hypfs/inode.c hypfs_read_iter
...
Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -> deadlock.
Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):
drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()
In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.
FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f715 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:
See
https://github.com/libfuse/osspd
https://lwn.net/Articles/308445
https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406
https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477
https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510
Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216
I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:
https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169
Let's fix this regression. The plan is:
1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS -
doing so would break many in-kernel nonseekable_open users which
actually use ppos in read/write handlers.
2. Add stream_open() to kernel to open stream-like non-seekable file
descriptors. Read and write on such file descriptors would never use
nor change ppos. And with that property on stream-like files read and
write will be running without taking f_pos lock - i.e. read and write
could be running simultaneously.
3. With semantic patch search and convert to stream_open all in-kernel
nonseekable_open users for which read and write actually do not
depend on ppos and where there is no other methods in file_operations
which assume @offset access.
4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
steam_open if that bit is present in filesystem open reply.
It was tempting to change fs/fuse/ open handler to use stream_open
instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and
write handlers
https://codesearch.debian.net/search?q=-%3Enonseekable+%3D
https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080
https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346
https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481
so if we would do such a change it will break a real user.
5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
from v3.14+ (the kernel where 9c225f2655 first appeared).
This will allow to patch OSSPD and other FUSE filesystems that
provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
in their open handler and this way avoid the deadlock on all kernel
versions. This should work because fs/fuse/ ignores unknown open
flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel
that is not aware of FOPEN_STREAM will be < v3.14 where just
FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
write deadlock.
This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.
Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.
The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures. These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time. Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.
Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
Merge misc fixes from Andrew Morton:
"14 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
kernel/sysctl.c: fix out-of-bounds access when setting file-max
mm/util.c: fix strndup_user() comment
sh: fix multiple function definition build errors
MAINTAINERS: add maintainer and replacing reviewer ARM/NUVOTON NPCM
MAINTAINERS: fix bad pattern in ARM/NUVOTON NPCM
mm: writeback: use exact memcg dirty counts
psi: clarify the units used in pressure files
mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd()
hugetlbfs: fix memory leak for resv_map
mm: fix vm_fault_t cast in VM_FAULT_GET_HINDEX()
lib/lzo: fix bugs for very short or empty input
include/linux/bitrev.h: fix constant bitrev
kmemleak: powerpc: skip scanning holes in the .bss section
lib/string.c: implement a basic bcmp
|
|
Since commit a983b5ebee57 ("mm: memcontrol: fix excessive complexity in
memory.stat reporting") memcg dirty and writeback counters are managed
as:
1) per-memcg per-cpu values in range of [-32..32]
2) per-memcg atomic counter
When a per-cpu counter cannot fit in [-32..32] it's flushed to the
atomic. Stat readers only check the atomic. Thus readers such as
balance_dirty_pages() may see a nontrivial error margin: 32 pages per
cpu.
Assuming 100 cpus:
4k x86 page_size: 13 MiB error per memcg
64k ppc page_size: 200 MiB error per memcg
Considering that dirty+writeback are used together for some decisions the
errors double.
This inaccuracy can lead to undeserved oom kills. One nasty case is
when all per-cpu counters hold positive values offsetting an atomic
negative value (i.e. per_cpu[*]=32, atomic=n_cpu*-32).
balance_dirty_pages() only consults the atomic and does not consider
throttling the next n_cpu*32 dirty pages. If the file_lru is in the
13..200 MiB range then there's absolutely no dirty throttling, which
burdens vmscan with only dirty+writeback pages thus resorting to oom
kill.
It could be argued that tiny containers are not supported, but it's more
subtle. It's the amount the space available for file lru that matters.
If a container has memory.max-200MiB of non reclaimable memory, then it
will also suffer such oom kills on a 100 cpu machine.
The following test reliably ooms without this patch. This patch avoids
oom kills.
$ cat test
mount -t cgroup2 none /dev/cgroup
cd /dev/cgroup
echo +io +memory > cgroup.subtree_control
mkdir test
cd test
echo 10M > memory.max
(echo $BASHPID > cgroup.procs && exec /memcg-writeback-stress /foo)
(echo $BASHPID > cgroup.procs && exec dd if=/dev/zero of=/foo bs=2M count=100)
$ cat memcg-writeback-stress.c
/*
* Dirty pages from all but one cpu.
* Clean pages from the non dirtying cpu.
* This is to stress per cpu counter imbalance.
* On a 100 cpu machine:
* - per memcg per cpu dirty count is 32 pages for each of 99 cpus
* - per memcg atomic is -99*32 pages
* - thus the complete dirty limit: sum of all counters 0
* - balance_dirty_pages() only sees atomic count -99*32 pages, which
* it max()s to 0.
* - So a workload can dirty -99*32 pages before balance_dirty_pages()
* cares.
*/
#define _GNU_SOURCE
#include <err.h>
#include <fcntl.h>
#include <sched.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/sysinfo.h>
#include <sys/types.h>
#include <unistd.h>
static char *buf;
static int bufSize;
static void set_affinity(int cpu)
{
cpu_set_t affinity;
CPU_ZERO(&affinity);
CPU_SET(cpu, &affinity);
if (sched_setaffinity(0, sizeof(affinity), &affinity))
err(1, "sched_setaffinity");
}
static void dirty_on(int output_fd, int cpu)
{
int i, wrote;
set_affinity(cpu);
for (i = 0; i < 32; i++) {
for (wrote = 0; wrote < bufSize; ) {
int ret = write(output_fd, buf+wrote, bufSize-wrote);
if (ret == -1)
err(1, "write");
wrote += ret;
}
}
}
int main(int argc, char **argv)
{
int cpu, flush_cpu = 1, output_fd;
const char *output;
if (argc != 2)
errx(1, "usage: output_file");
output = argv[1];
bufSize = getpagesize();
buf = malloc(getpagesize());
if (buf == NULL)
errx(1, "malloc failed");
output_fd = open(output, O_CREAT|O_RDWR);
if (output_fd == -1)
err(1, "open(%s)", output);
for (cpu = 0; cpu < get_nprocs(); cpu++) {
if (cpu != flush_cpu)
dirty_on(output_fd, cpu);
}
set_affinity(flush_cpu);
if (fsync(output_fd))
err(1, "fsync(%s)", output);
if (close(output_fd))
err(1, "close(%s)", output);
free(buf);
}
Make balance_dirty_pages() and wb_over_bg_thresh() work harder to
collect exact per memcg counters. This avoids the aforementioned oom
kills.
This does not affect the overhead of memory.stat, which still reads the
single atomic counter.
Why not use percpu_counter? memcg already handles cpus going offline, so
no need for that overhead from percpu_counter. And the percpu_counter
spinlocks are more heavyweight than is required.
It probably also makes sense to use exact dirty and writeback counters
in memcg oom reports. But that is saved for later.
Link: http://lkml.kernel.org/r/20190329174609.164344-1-gthelen@google.com
Signed-off-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org> [4.16+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Symmetrically to VM_FAULT_SET_HINDEX(), we need a force-cast in
VM_FAULT_GET_HINDEX() to tell sparse that this is intentional.
Sparse complains about the current code when building a kernel with
CONFIG_MEMORY_FAILURE:
arch/x86/mm/fault.c:1058:53: warning: restricted vm_fault_t degrades to integer
Link: http://lkml.kernel.org/r/20190327204117.35215-1-jannh@google.com
Fixes: 3d3539018d2c ("mm: create the new vm_fault_t type")
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
clang points out with hundreds of warnings that the bitrev macros have a
problem with constant input:
drivers/hwmon/sht15.c:187:11: error: variable '__x' is uninitialized when used within its own initialization
[-Werror,-Wuninitialized]
u8 crc = bitrev8(data->val_status & 0x0F);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/bitrev.h:102:21: note: expanded from macro 'bitrev8'
__constant_bitrev8(__x) : \
~~~~~~~~~~~~~~~~~~~^~~~
include/linux/bitrev.h:67:11: note: expanded from macro '__constant_bitrev8'
u8 __x = x; \
~~~ ^
Both the bitrev and the __constant_bitrev macros use an internal
variable named __x, which goes horribly wrong when passing one to the
other.
The obvious fix is to rename one of the variables, so this adds an extra
'_'.
It seems we got away with this because
- there are only a few drivers using bitrev macros
- usually there are no constant arguments to those
- when they are constant, they tend to be either 0 or (unsigned)-1
(drivers/isdn/i4l/isdnhdlc.o, drivers/iio/amplifiers/ad8366.c) and
give the correct result by pure chance.
In fact, the only driver that I could find that gets different results
with this is drivers/net/wan/slic_ds26522.c, which in turn is a driver
for fairly rare hardware (adding the maintainer to Cc for testing).
Link: http://lkml.kernel.org/r/20190322140503.123580-1-arnd@arndb.de
Fixes: 556d2f055bf6 ("ARM: 8187/1: add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Zhao Qiang <qiang.zhao@nxp.com>
Cc: Yalin Wang <yalin.wang@sonymobile.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
A recent optimization in Clang (r355672) lowers comparisons of the
return value of memcmp against zero to comparisons of the return value
of bcmp against zero. This helps some platforms that implement bcmp
more efficiently than memcmp. glibc simply aliases bcmp to memcmp, but
an optimized implementation is in the works.
This results in linkage failures for all targets with Clang due to the
undefined symbol. For now, just implement bcmp as a tailcail to memcmp
to unbreak the build. This routine can be further optimized in the
future.
Other ideas discussed:
* A weak alias was discussed, but breaks for architectures that define
their own implementations of memcmp since aliases to declarations are
not permitted (only definitions). Arch-specific memcmp
implementations typically declare memcmp in C headers, but implement
them in assembly.
* -ffreestanding also is used sporadically throughout the kernel.
* -fno-builtin-bcmp doesn't work when doing LTO.
Link: https://bugs.llvm.org/show_bug.cgi?id=41035
Link: https://code.woboq.org/userspace/glibc/string/memcmp.c.html#bcmp
Link: https://github.com/llvm/llvm-project/commit/8e16d73346f8091461319a7dfc4ddd18eedcff13
Link: https://github.com/ClangBuiltLinux/linux/issues/416
Link: http://lkml.kernel.org/r/20190313211335.165605-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Reported-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: James Y Knight <jyknight@google.com>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull syscall-get-arguments cleanup and fixes from Steven Rostedt:
"Andy Lutomirski approached me to tell me that the
syscall_get_arguments() implementation in x86 was horrible and gcc
certainly gets it wrong.
He said that since the tracepoints only pass in 0 and 6 for i and n
repectively, it should be optimized for that case. Inspecting the
kernel, I discovered that all users pass in 0 for i and only one file
passing in something other than 6 for the number of arguments. That
code happens to be my own code used for the special syscall tracing.
That can easily be converted to just using 0 and 6 as well, and only
copying what is needed. Which is probably the faster path anyway for
that case.
Along the way, a couple of real fixes came from this as the
syscall_get_arguments() function was incorrect for csky and riscv.
x86 has been optimized to for the new interface that removes the
variable number of arguments, but the other architectures could still
use some loving and take more advantage of the simpler interface"
* tag 'trace-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
syscalls: Remove start and number from syscall_set_arguments() args
syscalls: Remove start and number from syscall_get_arguments() args
csky: Fix syscall_get_arguments() and syscall_set_arguments()
riscv: Fix syscall_get_arguments() and syscall_set_arguments()
tracing/syscalls: Pass in hardcoded 6 into syscall_get_arguments()
ptrace: Remove maxargs from task_current_syscall()
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Minor comment merge conflict in mlx5.
Staging driver has a fixup due to the skb->xmit_more changes
in 'net-next', but was removed in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
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Handle event of power state change in the PCIE slot. When the event
occurs, check if query power state and PCI power fields is supported. If
so, read these fields from MPEIN (management PCIE info) register and
issue a corresponding message.
Signed-off-by: Aya Levin <ayal@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
This merge commit includes some misc shared code updates from mlx5-next branch needed
for net-next.
1) From Maxim, Remove un-used macros and spinlock from mlx5 code.
2) From Aya, Expose Management PCIE info register layout and add rate limit
print macros.
3) From Tariq, Compilation warning fix in fs_core.c
4) From Vu, Huy and Saeed, Improve mlx5 initialization flow:
The goal is to provide a better logical separation of mlx5 core
device initialization flow and will help to seamlessly support
creating different mlx5 device types such as PF, VF and SF
mlx5 sub-function virtual devices.
Mlx5_core driver needs to separate HCA resources from pci resources.
Its initialize/load/unload will be broken into stages:
1. Initialize common data structures
2. Setup function which initializes pci resources (for PF/VF)
or some other specific resources for virtual device
3. Initialize software objects according to hardware capabilities
4. Load all mlx5_core components
It is also necessary to detach mlx5_core mdev name/message from pci
device mdev->pdev name/message for a clearer report/debug of
different mlx5 device types.
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
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Provide a nice little shortcut for mapping a single bvec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
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In a lot of places we want to know the DMA direction for a given
struct request. Add a little helper to make it a littler easier.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
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This provides a nice little shortcut to get the integrity data for
drivers like NVMe that only support a single integrity segment.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
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Return the currently active bvec segment, potentially spanning multiple
pages.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
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Pull networking fixes from David Miller:
1) Several hash table refcount fixes in batman-adv, from Sven
Eckelmann.
2) Use after free in bpf_evict_inode(), from Daniel Borkmann.
3) Fix mdio bus registration in ixgbe, from Ivan Vecera.
4) Unbounded loop in __skb_try_recv_datagram(), from Paolo Abeni.
5) ila rhashtable corruption fix from Herbert Xu.
6) Don't allow upper-devices to be added to vrf devices, from Sabrina
Dubroca.
7) Add qmi_wwan device ID for Olicard 600, from Bjørn Mork.
8) Don't leave skb->next poisoned in __netif_receive_skb_list_ptype,
from Alexander Lobakin.
9) Missing IDR checks in mlx5 driver, from Aditya Pakki.
10) Fix false connection termination in ktls, from Jakub Kicinski.
11) Work around some ASPM issues with r8169 by disabling rx interrupt
coalescing on certain chips. From Heiner Kallweit.
12) Properly use per-cpu qstat values on NOLOCK qdiscs, from Paolo
Abeni.
13) Fully initialize sockaddr_in structures in SCTP, from Xin Long.
14) Various BPF flow dissector fixes from Stanislav Fomichev.
15) Divide by zero in act_sample, from Davide Caratti.
16) Fix bridging multicast regression introduced by rhashtable
conversion, from Nikolay Aleksandrov.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (106 commits)
ibmvnic: Fix completion structure initialization
ipv6: sit: reset ip header pointer in ipip6_rcv
net: bridge: always clear mcast matching struct on reports and leaves
libcxgb: fix incorrect ppmax calculation
vlan: conditional inclusion of FCoE hooks to match netdevice.h and bnx2x
sch_cake: Make sure we can write the IP header before changing DSCP bits
sch_cake: Use tc_skb_protocol() helper for getting packet protocol
tcp: Ensure DCTCP reacts to losses
net/sched: act_sample: fix divide by zero in the traffic path
net: thunderx: fix NULL pointer dereference in nicvf_open/nicvf_stop
net: hns: Fix sparse: some warnings in HNS drivers
net: hns: Fix WARNING when remove HNS driver with SMMU enabled
net: hns: fix ICMP6 neighbor solicitation messages discard problem
net: hns: Fix probabilistic memory overwrite when HNS driver initialized
net: hns: Use NAPI_POLL_WEIGHT for hns driver
net: hns: fix KASAN: use-after-free in hns_nic_net_xmit_hw()
flow_dissector: rst'ify documentation
ipv6: Fix dangling pointer when ipv6 fragment
net-gro: Fix GRO flush when receiving a GSO packet.
flow_dissector: document BPF flow dissector environment
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