Commit Graph

117408 Commits

Author SHA1 Message Date
Steven Rostedt (VMware)
46f9469247 ftrace: Rename ftrace_graph_stub to ftrace_stub_graph
The ftrace_graph_stub was created and points to ftrace_stub as a way to
assign the functon graph tracer function pointer to a stub function with a
different prototype than what ftrace_stub has and not trigger the C
verifier. The ftrace_graph_stub was created via the linker script
vmlinux.lds.h. Unfortunately, powerpc already uses the name
ftrace_graph_stub for its internal implementation of the function graph
tracer, and even though powerpc would still build, the change via the linker
script broke function tracer on powerpc from working.

By using the name ftrace_stub_graph, which does not exist anywhere else in
the kernel, this should not be a problem.

Link: https://lore.kernel.org/r/1573849732.5937.136.camel@lca.pw

Fixes: b83b43ffc6 ("fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stub")
Reorted-by: Qian Cai <cai@lca.pw>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18 11:42:16 -05:00
Steven Rostedt (VMware)
ea806eb3ea ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization
If a direct ftrace callback is at a location that does not have any other
ftrace helpers attached to it, it is possible to simply just change the
text to call the new caller (if the architecture supports it). But this
requires special architecture code. Currently, modify_ftrace_direct() uses a
trick to add a stub ftrace callback to the location forcing it to call the
ftrace iterator. Then it can change the direct helper to call the new
function in C, and then remove the stub. Removing the stub will have the
location now call the new location that the direct helper is using.

The new helper function does the registering the stub trick, but is a weak
function, allowing an architecture to override it to do something a bit more
direct.

Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18 11:42:09 -05:00
Tejun Heo
496074f94b blk-cgroup: cgroup_rstat_updated() shouldn't be called on cgroup1
Currently, cgroup rstat is supported only on cgroup2 hierarchy and
rstat functions shouldn't be called on cgroup1 cgroups.  While
converting blk-cgroup core statistics to rstat, f733164829
("blk-cgroup: reimplement basic IO stats using cgroup rstat")
accidentally ended up calling cgroup_rstat_updated() on cgroup1
cgroups causing crashes.

Longer term, we probably should add cgroup1 support to rstat but for
now let's mask the call directly.

Fixes: f733164829 ("blk-cgroup: reimplement basic IO stats using cgroup rstat")
Tested-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-18 08:40:41 -07:00
Ingo Molnar
b21feab0b8 Merge tag 'v5.4-rc8' into sched/core, to pick up fixes and dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-18 14:41:02 +01:00
Vinod Koul
d2522335c9 ALSA: compress: add flac decoder params
The current design of sending codec parameters assumes that decoders
will have parsers so they can parse the encoded stream for parameters
and configure the decoder.

But this assumption may not be universally true and we know some DSPs
which do not contain the parsers so additional parameters are required
to be passed.

So add these parameters starting with FLAC decoder. The size of
snd_codec_options is still 120 bytes after this change (due to this
being a union)

Co-developed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20191115102705.649976-2-vkoul@kernel.org
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-11-18 13:02:25 +00:00
David Sterba
1d2e7c7c3e btrfs: tracepoints: constify all pointers
We don't modify the data passed to tracepoints, some of the declarations
are already const, add it to the rest.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:47:00 +01:00
David Sterba
94c3f6c6b8 btrfs: tracepoints: drop typecasts from printk
Remove typecasts from trace printk, adjust types and move typecast to
the assignment if necessary. When assigning, the types are more obvious
compared to matching the variables to the format strings.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:47:00 +01:00
Chengguang Xu
b9b1a53e18 btrfs: use enum for extent type defines
Use enum to replace macro definitions of extent types.

Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:55 +01:00
Omar Sandoval
c9eb55db84 btrfs: get rid of pointless wtag variable in async-thread.c
Commit ac0c7cf8be ("btrfs: fix crash when tracepoint arguments are
freed by wq callbacks") added a void pointer, wtag, which is passed into
trace_btrfs_all_work_done() instead of the freed work item. This is
silly for a few reasons:

1. The freed work item still has the same address.
2. work is still in scope after it's freed, so assigning wtag doesn't
   stop anyone from using it.
3. The tracepoint has always taken a void * argument, so assigning wtag
   doesn't actually make things any more type-safe. (Note that the
   original bug in commit bc074524e1 ("btrfs: prefix fsid to all trace
   events") was that the void * was implicitly casted when it was passed
   to btrfs_work_owner() in the trace point itself).

Instead, let's add some clearer warnings as comments.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 12:46:49 +01:00
Andrii Nakryiko
fc9702273e bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY
Add ability to memory-map contents of BPF array map. This is extremely useful
for working with BPF global data from userspace programs. It allows to avoid
typical bpf_map_{lookup,update}_elem operations, improving both performance
and usability.

There had to be special considerations for map freezing, to avoid having
writable memory view into a frozen map. To solve this issue, map freezing and
mmap-ing is happening under mutex now:
  - if map is already frozen, no writable mapping is allowed;
  - if map has writable memory mappings active (accounted in map->writecnt),
    map freezing will keep failing with -EBUSY;
  - once number of writable memory mappings drops to zero, map freezing can be
    performed again.

Only non-per-CPU plain arrays are supported right now. Maps with spinlocks
can't be memory mapped either.

For BPF_F_MMAPABLE array, memory allocation has to be done through vmalloc()
to be mmap()'able. We also need to make sure that array data memory is
page-sized and page-aligned, so we over-allocate memory in such a way that
struct bpf_array is at the end of a single page of memory with array->value
being aligned with the start of the second page. On deallocation we need to
accomodate this memory arrangement to free vmalloc()'ed memory correctly.

One important consideration regarding how memory-mapping subsystem functions.
Memory-mapping subsystem provides few optional callbacks, among them open()
and close().  close() is called for each memory region that is unmapped, so
that users can decrease their reference counters and free up resources, if
necessary. open() is *almost* symmetrical: it's called for each memory region
that is being mapped, **except** the very first one. So bpf_map_mmap does
initial refcnt bump, while open() will do any extra ones after that. Thus
number of close() calls is equal to number of open() calls plus one more.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-4-andriin@fb.com
2019-11-18 11:41:59 +01:00
Andrii Nakryiko
85192dbf4d bpf: Convert bpf_prog refcnt to atomic64_t
Similarly to bpf_map's refcnt/usercnt, convert bpf_prog's refcnt to atomic64
and remove artificial 32k limit. This allows to make bpf_prog's refcounting
non-failing, simplifying logic of users of bpf_prog_add/bpf_prog_inc.

Validated compilation by running allyesconfig kernel build.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-3-andriin@fb.com
2019-11-18 11:41:59 +01:00
Andrii Nakryiko
1e0bd5a091 bpf: Switch bpf_map ref counter to atomic64_t so bpf_map_inc() never fails
92117d8443 ("bpf: fix refcnt overflow") turned refcounting of bpf_map into
potentially failing operation, when refcount reaches BPF_MAX_REFCNT limit
(32k). Due to using 32-bit counter, it's possible in practice to overflow
refcounter and make it wrap around to 0, causing erroneous map free, while
there are still references to it, causing use-after-free problems.

But having a failing refcounting operations are problematic in some cases. One
example is mmap() interface. After establishing initial memory-mapping, user
is allowed to arbitrarily map/remap/unmap parts of mapped memory, arbitrarily
splitting it into multiple non-contiguous regions. All this happening without
any control from the users of mmap subsystem. Rather mmap subsystem sends
notifications to original creator of memory mapping through open/close
callbacks, which are optionally specified during initial memory mapping
creation. These callbacks are used to maintain accurate refcount for bpf_map
(see next patch in this series). The problem is that open() callback is not
supposed to fail, because memory-mapped resource is set up and properly
referenced. This is posing a problem for using memory-mapping with BPF maps.

One solution to this is to maintain separate refcount for just memory-mappings
and do single bpf_map_inc/bpf_map_put when it goes from/to zero, respectively.
There are similar use cases in current work on tcp-bpf, necessitating extra
counter as well. This seems like a rather unfortunate and ugly solution that
doesn't scale well to various new use cases.

Another approach to solve this is to use non-failing refcount_t type, which
uses 32-bit counter internally, but, once reaching overflow state at UINT_MAX,
stays there. This utlimately causes memory leak, but prevents use after free.

But given refcounting is not the most performance-critical operation with BPF
maps (it's not used from running BPF program code), we can also just switch to
64-bit counter that can't overflow in practice, potentially disadvantaging
32-bit platforms a tiny bit. This simplifies semantics and allows above
described scenarios to not worry about failing refcount increment operation.

In terms of struct bpf_map size, we are still good and use the same amount of
space:

BEFORE (3 cache lines, 8 bytes of padding at the end):
struct bpf_map {
	const struct bpf_map_ops  * ops __attribute__((__aligned__(64))); /*     0     8 */
	struct bpf_map *           inner_map_meta;       /*     8     8 */
	void *                     security;             /*    16     8 */
	enum bpf_map_type  map_type;                     /*    24     4 */
	u32                        key_size;             /*    28     4 */
	u32                        value_size;           /*    32     4 */
	u32                        max_entries;          /*    36     4 */
	u32                        map_flags;            /*    40     4 */
	int                        spin_lock_off;        /*    44     4 */
	u32                        id;                   /*    48     4 */
	int                        numa_node;            /*    52     4 */
	u32                        btf_key_type_id;      /*    56     4 */
	u32                        btf_value_type_id;    /*    60     4 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	struct btf *               btf;                  /*    64     8 */
	struct bpf_map_memory memory;                    /*    72    16 */
	bool                       unpriv_array;         /*    88     1 */
	bool                       frozen;               /*    89     1 */

	/* XXX 38 bytes hole, try to pack */

	/* --- cacheline 2 boundary (128 bytes) --- */
	atomic_t                   refcnt __attribute__((__aligned__(64))); /*   128     4 */
	atomic_t                   usercnt;              /*   132     4 */
	struct work_struct work;                         /*   136    32 */
	char                       name[16];             /*   168    16 */

	/* size: 192, cachelines: 3, members: 21 */
	/* sum members: 146, holes: 1, sum holes: 38 */
	/* padding: 8 */
	/* forced alignments: 2, forced holes: 1, sum forced holes: 38 */
} __attribute__((__aligned__(64)));

AFTER (same 3 cache lines, no extra padding now):
struct bpf_map {
	const struct bpf_map_ops  * ops __attribute__((__aligned__(64))); /*     0     8 */
	struct bpf_map *           inner_map_meta;       /*     8     8 */
	void *                     security;             /*    16     8 */
	enum bpf_map_type  map_type;                     /*    24     4 */
	u32                        key_size;             /*    28     4 */
	u32                        value_size;           /*    32     4 */
	u32                        max_entries;          /*    36     4 */
	u32                        map_flags;            /*    40     4 */
	int                        spin_lock_off;        /*    44     4 */
	u32                        id;                   /*    48     4 */
	int                        numa_node;            /*    52     4 */
	u32                        btf_key_type_id;      /*    56     4 */
	u32                        btf_value_type_id;    /*    60     4 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	struct btf *               btf;                  /*    64     8 */
	struct bpf_map_memory memory;                    /*    72    16 */
	bool                       unpriv_array;         /*    88     1 */
	bool                       frozen;               /*    89     1 */

	/* XXX 38 bytes hole, try to pack */

	/* --- cacheline 2 boundary (128 bytes) --- */
	atomic64_t                 refcnt __attribute__((__aligned__(64))); /*   128     8 */
	atomic64_t                 usercnt;              /*   136     8 */
	struct work_struct work;                         /*   144    32 */
	char                       name[16];             /*   176    16 */

	/* size: 192, cachelines: 3, members: 21 */
	/* sum members: 154, holes: 1, sum holes: 38 */
	/* forced alignments: 2, forced holes: 1, sum forced holes: 38 */
} __attribute__((__aligned__(64)));

This patch, while modifying all users of bpf_map_inc, also cleans up its
interface to match bpf_map_put with separate operations for bpf_map_inc and
bpf_map_inc_with_uref (to match bpf_map_put and bpf_map_put_with_uref,
respectively). Also, given there are no users of bpf_map_inc_not_zero
specifying uref=true, remove uref flag and default to uref=false internally.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-2-andriin@fb.com
2019-11-18 11:41:59 +01:00
Trond Myklebust
4e121fcae8 Merge tag 'nfs-rdma-for-5.5-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
NFSoRDMA Client Updates for Linux 5.5

New Features:
- New tracepoints for congestion control and Local Invalidate WRs

Bugfixes and Cleanups:
- Eliminate log noise in call_reserveresult
- Fix unstable connections after a reconnect
- Clean up some code duplication
- Close race between waking a sender and posting a receive
- Fix MR list corruption, and clean up MR usage
- Remove unused rpcrdma_sendctx fields
- Try to avoid DMA mapping pages if it is too costly
- Wake pending tasks if connection fails
- Replace some dprintk()s with tracepoints
2019-11-18 10:55:55 +01:00
Bradley Bolen
f3d7c2292d mmc: core: Fix size overflow for mmc partitions
With large eMMC cards, it is possible to create general purpose
partitions that are bigger than 4GB.  The size member of the mmc_part
struct is only an unsigned int which overflows for gp partitions larger
than 4GB.  Change this to a u64 to handle the overflow.

Signed-off-by: Bradley Bolen <bradleybolen@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-11-18 10:05:38 +01:00
Linus Torvalds
ec53851967 Merge tag 'iommu-fixes-v5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu fixes from Joerg Roedel:

 - Fix for Intel IOMMU to correct invalidation commands when in SVA
   mode.

 - Update MAINTAINERS entry for Intel IOMMU

* tag 'iommu-fixes-v5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Fix QI_DEV_IOTLB_PFSID and QI_DEV_EIOTLB_PFSID macros
  MAINTAINERS: Update for INTEL IOMMU (VT-d) entry
2019-11-17 11:27:44 -08:00
Dan Williams
adbb68293f libnvdimm: Move nd_device_attribute_group to device_type
A 'struct device_type' instance can carry default attributes for the
device. Use this facility to remove the export of
nd_device_attribute_group and put the responsibility on the core rather
than leaf implementations to define this attribute.

For regions this creates a new nd_region_attribute_groups[] added to the
per-region device-type instances.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/157309901138.1582359.12909354140826530394.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-11-17 09:17:39 -08:00
Christoph Hellwig
72b894b09a IB/umem: remove the dmasync argument to ib_umem_get
The argument is always ignored, so remove it.

Link: https://lore.kernel.org/r/20191113073214.9514-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-11-17 10:37:00 -04:00
David S. Miller
19b7e21c55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Lots of overlapping changes and parallel additions, stuff
like that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 21:51:42 -08:00
Sebastian Andrzej Siewior
9e8d42a0f7 percpu-refcount: Use normal instead of RCU-sched"
This is a revert of commit
   a4244454df ("percpu-refcount: use RCU-sched insted of normal RCU")

which claims the only reason for using RCU-sched is
   "rcu_read_[un]lock() … are slightly more expensive than preempt_disable/enable()"

and
    "As the RCU critical sections are extremely short, using sched-RCU
    shouldn't have any latency implications."

The problem with using RCU-sched here is that it disables preemption and
the release callback (called from percpu_ref_put_many()) must not
acquire any sleeping locks like spinlock_t. This breaks PREEMPT_RT
because some of the users acquire spinlock_t locks in their callbacks.

Using rcu_read_lock() on PREEMPTION=n kernels is not any different
compared to rcu_read_lock_sched(). On PREEMPTION=y kernels there are
already performance issues due to additional preemption points.
Looking at the code, the rcu_read_lock() is just an increment and unlock
is almost just a decrement unless there is something special to do. Both
are functions while disabling preemption is inlined.
Doing a small benchmark, the minimal amount of time required was mostly
the same. The average time required was higher due to the higher MAX
value (which could be preemption). With DEBUG_PREEMPT=y it is
rcu_read_lock_sched() that takes a little longer due to the additional
debug code.

Convert back to normal RCU.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
2019-11-16 20:02:47 -08:00
Ard Biesheuvel
d63007eb95 crypto: ablkcipher - remove deprecated and unused ablkcipher support
Now that all users of the deprecated ablkcipher interface have been
moved to the skcipher interface, ablkcipher is no longer used and
can be removed.

Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:49 +08:00
Ard Biesheuvel
d95312a3cc crypto: lib/chacha20poly1305 - reimplement crypt_from_sg() routine
Reimplement the library routines to perform chacha20poly1305 en/decryption
on scatterlists, without [ab]using the [deprecated] blkcipher interface,
which is rather heavyweight and does things we don't really need.

Instead, we use the sg_miter API in a novel and clever way, to iterate
over the scatterlist in-place (i.e., source == destination, which is the
only way this library is expected to be used). That way, we don't have to
iterate over two scatterlists in parallel.

Another optimization is that, instead of relying on the blkcipher walker
to present the input in suitable chunks, we recognize that ChaCha is a
streamcipher, and so we can simply deal with partial blocks by keeping a
block of cipherstream on the stack and use crypto_xor() to mix it with
the in/output.

Finally, we omit the scatterwalk_and_copy() call if the last element of
the scatterlist covers the MAC as well (which is the common case),
avoiding the need to walk the scatterlist and kmap() the page twice.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:44 +08:00
Ard Biesheuvel
ed20078b7e crypto: chacha20poly1305 - import construction and selftest from Zinc
This incorporates the chacha20poly1305 from the Zinc library, retaining
the library interface, but replacing the implementation with calls into
the code that already existed in the kernel's crypto API.

Note that this library API does not implement RFC7539 fully, given that
it is limited to 64-bit nonces. (The 96-bit nonce version that was part
of the selftest only has been removed, along with the 96-bit nonce test
vectors that only tested the selftest but not the actual library itself)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:44 +08:00
Jason A. Donenfeld
0ed42a6f43 crypto: curve25519 - generic C library implementations
This contains two formally verified C implementations of the Curve25519
scalar multiplication function, one for 32-bit systems, and one for
64-bit systems whose compiler supports efficient 128-bit integer types.
Not only are these implementations formally verified, but they are also
the fastest available C implementations. They have been modified to be
friendly to kernel space and to be generally less horrendous looking,
but still an effort has been made to retain their formally verified
characteristic, and so the C might look slightly unidiomatic.

The 64-bit version comes from HACL*: https://github.com/project-everest/hacl-star
The 32-bit version comes from Fiat: https://github.com/mit-plv/fiat-crypto

Information: https://cr.yp.to/ecdh.html

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
[ardb: - move from lib/zinc to lib/crypto
       - replace .c #includes with Kconfig based object selection
       - drop simd handling and simplify support for per-arch versions ]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:43 +08:00
Ard Biesheuvel
7f9b088092 crypto: blake2s - implement generic shash driver
Wire up our newly added Blake2s implementation via the shash API.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:42 +08:00
Jason A. Donenfeld
66d7fb94e4 crypto: blake2s - generic C library implementation and selftest
The C implementation was originally based on Samuel Neves' public
domain reference implementation but has since been heavily modified
for the kernel. We're able to do compile-time optimizations by moving
some scaffolding around the final function into the header file.

Information: https://blake2.net/

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Samuel Neves <sneves@dei.uc.pt>
Co-developed-by: Samuel Neves <sneves@dei.uc.pt>
[ardb: - move from lib/zinc to lib/crypto
       - remove simd handling
       - rewrote selftest for better coverage
       - use fixed digest length for blake2s_hmac() and rename to
         blake2s256_hmac() ]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:42 +08:00
Ard Biesheuvel
1b2c6a5120 crypto: x86/poly1305 - depend on generic library not generic shash
Remove the dependency on the generic Poly1305 driver. Instead, depend
on the generic library so that we only reuse code without pulling in
the generic skcipher implementation as well.

While at it, remove the logic that prefers the non-SIMD path for short
inputs - this is no longer necessary after recent FPU handling changes
on x86.

Since this removes the last remaining user of the routines exported
by the generic shash driver, unexport them and make them static.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:41 +08:00
Ard Biesheuvel
a1d9306409 crypto: poly1305 - expose init/update/final library interface
Expose the existing generic Poly1305 code via a init/update/final
library interface so that callers are not required to go through
the crypto API's shash abstraction to access it. At the same time,
make some preparations so that the library implementation can be
superseded by an accelerated arch-specific version in the future.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:41 +08:00
Ard Biesheuvel
ad8f5b8838 crypto: x86/poly1305 - unify Poly1305 state struct with generic code
In preparation of exposing a Poly1305 library interface directly from
the accelerated x86 driver, align the state descriptor of the x86 code
with the one used by the generic driver. This is needed to make the
library interface unified between all implementations.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:41 +08:00
Ard Biesheuvel
48ea8c6ebc crypto: poly1305 - move core routines into a separate library
Move the core Poly1305 routines shared between the generic Poly1305
shash driver and the Adiantum and NHPoly1305 drivers into a separate
library so that using just this pieces does not pull in the crypto
API pieces of the generic Poly1305 routine.

In a subsequent patch, we will augment this generic library with
init/update/final routines so that Poyl1305 algorithm can be used
directly without the need for using the crypto API's shash abstraction.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:41 +08:00
Ard Biesheuvel
22cf705360 crypto: chacha - unexport chacha_generic routines
Now that all users of generic ChaCha code have moved to the core library,
there is no longer a need for the generic ChaCha skcpiher driver to
export parts of it implementation for reuse by other drivers. So drop
the exports, and make the symbols static.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:40 +08:00
Ard Biesheuvel
84e03fa39f crypto: x86/chacha - expose SIMD ChaCha routine as library function
Wire the existing x86 SIMD ChaCha code into the new ChaCha library
interface, so that users of the library interface will get the
accelerated version when available.

Given that calls into the library API will always go through the
routines in this module if it is enabled, switch to static keys
to select the optimal implementation available (which may be none
at all, in which case we defer to the generic implementation for
all invocations).

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:39 +08:00
Ard Biesheuvel
5fb8ef2580 crypto: chacha - move existing library code into lib/crypto
Currently, our generic ChaCha implementation consists of a permute
function in lib/chacha.c that operates on the 64-byte ChaCha state
directly [and which is always included into the core kernel since it
is used by the /dev/random driver], and the crypto API plumbing to
expose it as a skcipher.

In order to support in-kernel users that need the ChaCha streamcipher
but have no need [or tolerance] for going through the abstractions of
the crypto API, let's expose the streamcipher bits via a library API
as well, in a way that permits the implementation to be superseded by
an architecture specific one if provided.

So move the streamcipher code into a separate module in lib/crypto,
and expose the init() and crypt() routines to users of the library.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17 09:02:39 +08:00
Linus Torvalds
8be636dd8a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix memory leak in xfrm_state code, from Steffen Klassert.

 2) Fix races between devlink reload operations and device
    setup/cleanup, from Jiri Pirko.

 3) Null deref in NFC code, from Stephan Gerhold.

 4) Refcount fixes in SMC, from Ursula Braun.

 5) Memory leak in slcan open error paths, from Jouni Hogander.

 6) Fix ETS bandwidth validation in hns3, from Yonglong Liu.

 7) Info leak on short USB request answers in ax88172a driver, from
    Oliver Neukum.

 8) Release mem region properly in ep93xx_eth, from Chuhong Yuan.

 9) PTP config timestamp flags validation, from Richard Cochran.

10) Dangling pointers after SKB data realloc in seg6, from Andrea Mayer.

11) Missing free_netdev() in gemini driver, from Chuhong Yuan.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (56 commits)
  ipmr: Fix skb headroom in ipmr_get_route().
  net: hns3: cleanup of stray struct hns3_link_mode_mapping
  net/smc: fix fastopen for non-blocking connect()
  rds: ib: update WR sizes when bringing up connection
  net: gemini: add missed free_netdev
  net: dsa: tag_8021q: Fix dsa_8021q_restore_pvid for an absent pvid
  seg6: fix skb transport_header after decap_and_validate()
  seg6: fix srh pointer in get_srh()
  net: stmmac: Use the correct style for SPDX License Identifier
  octeontx2-af: Use the correct style for SPDX License Identifier
  ptp: Extend the test program to check the external time stamp flags.
  mlx5: Reject requests to enable time stamping on both edges.
  igb: Reject requests that fail to enable time stamping on both edges.
  dp83640: Reject requests to enable time stamping on both edges.
  mv88e6xxx: Reject requests to enable time stamping on both edges.
  ptp: Introduce strict checking of external time stamp options.
  renesas: reject unsupported external timestamp flags
  mlx5: reject unsupported external timestamp flags
  igb: reject unsupported external timestamp flags
  dp83640: reject unsupported external timestamp flags
  ...
2019-11-16 15:52:00 -08:00
Jonathan Lemon
c3f812cea0 page_pool: do not release pool until inflight == 0.
The page pool keeps track of the number of pages in flight, and
it isn't safe to remove the pool until all pages are returned.

Disallow removing the pool until all pages are back, so the pool
is always available for page producers.

Make the page pool responsible for its own delayed destruction
instead of relying on XDP, so the page pool can be used without
the xdp memory model.

When all pages are returned, free the pool and notify xdp if the
pool is registered with the xdp memory system.  Have the callback
perform a table walk since some drivers (cpsw) may share the pool
among multiple xdp_rxq_info.

Note that the increment of pages_state_release_cnt may result in
inflight == 0, resulting in the pool being released.

Fixes: d956a048cd ("xdp: force mem allocator removal and periodic warning")
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 12:39:10 -08:00
Hans de Goede
a079973f46 usb: typec: tcpm: Remove tcpc_config configuration mechanism
All configuration can and should be done through fwnodes instead of
through the tcpc_config struct and there are no existing users left of
struct tcpc_config, so lets remove it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191114111840.40876-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-16 14:45:31 +01:00
Lina Iyer
e35a6ae0eb pinctrl/msm: Setup GPIO chip in hierarchy
Some GPIOs are marked as wakeup capable and are routed to another
interrupt controller that is an always-domain and can detect interrupts
even when most of the SoC is powered off. The wakeup interrupt
controller wakes up the GIC and replays the interrupt at the GIC.

Setup the TLMM irqchip in hierarchy with the wakeup interrupt controller
and ensure the wakeup GPIOs are handled correctly.

Co-developed-by: Maulik Shah <mkshah@codeaurora.org>

Signed-off-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1573855915-9841-9-git-send-email-ilina@codeaurora.org

----
Changes in v2:
	- Address review comments
	- Fix Co-developed-by tag
Changes in v1:
	- Address minor review comments
	- Remove redundant call to set irq handler
	- Move irq_domain_qcom_handle_wakeup() to this patch
Changes in RFC v2:
	- Rebase on top of GPIO hierarchy support in linux-next
	- Set the chained irq handler for summary line
2019-11-16 10:23:15 +00:00
Lina Iyer
81ef8bf880 irqchip/qcom-pdc: Add irqdomain for wakeup capable GPIOs
Introduce a new domain for wakeup capable GPIOs. The domain can be
requested using the bus token DOMAIN_BUS_WAKEUP. In the following
patches, we will specify PDC as the wakeup-parent for the TLMM GPIO
irqchip. Requesting a wakeup GPIO will setup the GPIO and the
corresponding PDC interrupt as its parent.

Co-developed-by: Stephen Boyd <swboyd@chromium.org>

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1573855915-9841-5-git-send-email-ilina@codeaurora.org
2019-11-16 10:21:15 +00:00
Maulik Shah
4a169a95d8 genirq: Introduce irq_chip_get/set_parent_state calls
On certain QTI chipsets some GPIOs are direct-connect interrupts to the
GIC to be used as regular interrupt lines. When the GPIOs are not used
for interrupt generation the interrupt line is disabled. But disabling
the interrupt at GIC does not prevent the interrupt to be reported as
pending at GIC_ISPEND. Later, when drivers call enable_irq() on the
interrupt, an unwanted interrupt occurs.

Introduce get and set methods for irqchip's parent to clear it's pending
irq state. This then can be invoked by the GPIO interrupt controller on
the parents in it hierarchy to clear the interrupt before enabling the
interrupt.

Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1573855915-9841-7-git-send-email-ilina@codeaurora.org

[updated commit text and minor code fixes]
2019-11-16 10:20:02 +00:00
Lina Iyer
d46bca2b5d irqdomain: Add bus token DOMAIN_BUS_WAKEUP
A single controller can handle normal interrupts and wake-up interrupts
independently, with a different numbering space. It is thus crucial to
allow the driver for such a controller discriminate between the two.

A simple way to do so is to tag the wake-up irqdomain with a "bus token"
that indicates the wake-up domain. This slightly abuses the notion of
bus, but also radically simplifies the design of such a driver. Between
two evils, we choose the least damaging.

Suggested-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1573855915-9841-2-git-send-email-ilina@codeaurora.org
2019-11-16 10:18:52 +00:00
David Hildenbrand
2c91f8fc6c mm/memory_hotplug: fix try_offline_node()
try_offline_node() is pretty much broken right now:

 - The node span is updated when onlining memory, not when adding it. We
   ignore memory that was mever onlined. Bad.

 - We touch possible garbage memmaps. The pfn_to_nid(pfn) can easily
   trigger a kernel panic. Bad for memory that is offline but also bad
   for subsection hotadd with ZONE_DEVICE, whereby the memmap of the
   first PFN of a section might contain garbage.

 - Sections belonging to mixed nodes are not properly considered.

As memory blocks might belong to multiple nodes, we would have to walk
all pageblocks (or at least subsections) within present sections.
However, we don't have a way to identify whether a memmap that is not
online was initialized (relevant for ZONE_DEVICE).  This makes things
more complicated.

Luckily, we can piggy pack on the node span and the nid stored in memory
blocks.  Currently, the node span is grown when calling
move_pfn_range_to_zone() - e.g., when onlining memory, and shrunk when
removing memory, before calling try_offline_node().  Sysfs links are
created via link_mem_sections(), e.g., during boot or when adding
memory.

If the node still spans memory or if any memory block belongs to the
nid, we don't set the node offline.  As memory blocks that span multiple
nodes cannot get offlined, the nid stored in memory blocks is reliable
enough (for such online memory blocks, the node still spans the memory).

Introduce for_each_memory_block() to efficiently walk all memory blocks.

Note: We will soon stop shrinking the ZONE_DEVICE zone and the node span
when removing ZONE_DEVICE memory to fix similar issues (access of
garbage memmaps) - until we have a reliable way to identify whether
these memmaps were properly initialized.  This implies later, that once
a node had ZONE_DEVICE memory, we won't be able to set a node offline -
which should be acceptable.

Since commit f1dd2cd13c ("mm, memory_hotplug: do not associate
hotadded memory to zones until online") memory that is added is not
assoziated with a zone/node (memmap not initialized).  The introducing
commit 60a5a19e74 ("memory-hotplug: remove sysfs file of node")
already missed that we could have multiple nodes for a section and that
the zone/node span is updated when onlining pages, not when adding them.

I tested this by hotplugging two DIMMs to a memory-less and cpu-less
NUMA node.  The node is properly onlined when adding the DIMMs.  When
removing the DIMMs, the node is properly offlined.

Masayoshi Mizuma reported:

: Without this patch, memory hotplug fails as panic:
:
:  BUG: kernel NULL pointer dereference, address: 0000000000000000
:  ...
:  Call Trace:
:   remove_memory_block_devices+0x81/0xc0
:   try_remove_memory+0xb4/0x130
:   __remove_memory+0xa/0x20
:   acpi_memory_device_remove+0x84/0x100
:   acpi_bus_trim+0x57/0x90
:   acpi_bus_trim+0x2e/0x90
:   acpi_device_hotplug+0x2b2/0x4d0
:   acpi_hotplug_work_fn+0x1a/0x30
:   process_one_work+0x171/0x380
:   worker_thread+0x49/0x3f0
:   kthread+0xf8/0x130
:   ret_from_fork+0x35/0x40

[david@redhat.com: v3]
  Link: http://lkml.kernel.org/r/20191102120221.7553-1-david@redhat.com
Link: http://lkml.kernel.org/r/20191028105458.28320-1-david@redhat.com
Fixes: 60a5a19e74 ("memory-hotplug: remove sysfs file of node")
Fixes: f1dd2cd13c ("mm, memory_hotplug: do not associate hotadded memory to zones until online") # visiable after d0dc12e86b
Signed-off-by: David Hildenbrand <david@redhat.com>
Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Nayna Jain <nayna@linux.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-15 18:34:00 -08:00
Adrian Reber
49cb2fc42c fork: extend clone3() to support setting a PID
The main motivation to add set_tid to clone3() is CRIU.

To restore a process with the same PID/TID CRIU currently uses
/proc/sys/kernel/ns_last_pid. It writes the desired (PID - 1) to
ns_last_pid and then (quickly) does a clone(). This works most of the
time, but it is racy. It is also slow as it requires multiple syscalls.

Extending clone3() to support *set_tid makes it possible restore a
process using CRIU without accessing /proc/sys/kernel/ns_last_pid and
race free (as long as the desired PID/TID is available).

This clone3() extension places the same restrictions (CAP_SYS_ADMIN)
on clone3() with *set_tid as they are currently in place for ns_last_pid.

The original version of this change was using a single value for
set_tid. At the 2019 LPC, after presenting set_tid, it was, however,
decided to change set_tid to an array to enable setting the PID of a
process in multiple PID namespaces at the same time. If a process is
created in a PID namespace it is possible to influence the PID inside
and outside of the PID namespace. Details also in the corresponding
selftest.

To create a process with the following PIDs:

      PID NS level         Requested PID
        0 (host)              31496
        1                        42
        2                         1

For that example the two newly introduced parameters to struct
clone_args (set_tid and set_tid_size) would need to be:

  set_tid[0] = 1;
  set_tid[1] = 42;
  set_tid[2] = 31496;
  set_tid_size = 3;

If only the PIDs of the two innermost nested PID namespaces should be
defined it would look like this:

  set_tid[0] = 1;
  set_tid[1] = 42;
  set_tid_size = 2;

The PID of the newly created process would then be the next available
free PID in the PID namespace level 0 (host) and 42 in the PID namespace
at level 1 and the PID of the process in the innermost PID namespace
would be 1.

The set_tid array is used to specify the PID of a process starting
from the innermost nested PID namespaces up to set_tid_size PID namespaces.

set_tid_size cannot be larger then the current PID namespace level.

Signed-off-by: Adrian Reber <areber@redhat.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Acked-by: Andrei Vagin <avagin@gmail.com>
Link: https://lore.kernel.org/r/20191115123621.142252-1-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2019-11-15 23:49:22 +01:00
Alexei Starovoitov
5b92a28aae bpf: Support attaching tracing BPF program to other BPF programs
Allow FENTRY/FEXIT BPF programs to attach to other BPF programs of any type
including their subprograms. This feature allows snooping on input and output
packets in XDP, TC programs including their return values. In order to do that
the verifier needs to track types not only of vmlinux, but types of other BPF
programs as well. The verifier also needs to translate uapi/linux/bpf.h types
used by networking programs into kernel internal BTF types used by FENTRY/FEXIT
BPF programs. In some cases LLVM optimizations can remove arguments from BPF
subprograms without adjusting BTF info that LLVM backend knows. When BTF info
disagrees with actual types that the verifiers sees the BPF trampoline has to
fallback to conservative and treat all arguments as u64. The FENTRY/FEXIT
program can still attach to such subprograms, but it won't be able to recognize
pointer types like 'struct sk_buff *' and it won't be able to pass them to
bpf_skb_output() for dumping packets to user space. The FENTRY/FEXIT program
would need to use bpf_probe_read_kernel() instead.

The BPF_PROG_LOAD command is extended with attach_prog_fd field. When it's set
to zero the attach_btf_id is one vmlinux BTF type ids. When attach_prog_fd
points to previously loaded BPF program the attach_btf_id is BTF type id of
main function or one of its subprograms.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-18-ast@kernel.org
2019-11-15 23:45:24 +01:00
Alexei Starovoitov
8c1b6e69dc bpf: Compare BTF types of functions arguments with actual types
Make the verifier check that BTF types of function arguments match actual types
passed into top-level BPF program and into BPF-to-BPF calls. If types match
such BPF programs and sub-programs will have full support of BPF trampoline. If
types mismatch the trampoline has to be conservative. It has to save/restore
five program arguments and assume 64-bit scalars.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-17-ast@kernel.org
2019-11-15 23:45:02 +01:00
Alexei Starovoitov
91cc1a9974 bpf: Annotate context types
Annotate BPF program context types with program-side type and kernel-side type.
This type information is used by the verifier. btf_get_prog_ctx_type() is
used in the later patches to verify that BTF type of ctx in BPF program matches to
kernel expected ctx type. For example, the XDP program type is:
BPF_PROG_TYPE(BPF_PROG_TYPE_XDP, xdp, struct xdp_md, struct xdp_buff)
That means that XDP program should be written as:
int xdp_prog(struct xdp_md *ctx) { ... }

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-16-ast@kernel.org
2019-11-15 23:44:48 +01:00
Pablo Neira Ayuso
5c27d8d76c netfilter: nf_flow_table_offload: add IPv6 support
Add nf_flow_rule_route_ipv6() and use it from the IPv6 and the inet
flowtable type definitions. Rename the nf_flow_rule_route() function to
nf_flow_rule_route_ipv4().

Adjust maximum number of actions, which now becomes 16 to leave
sufficient room for the IPv6 address mangling for NAT.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-11-15 23:44:47 +01:00
Alexei Starovoitov
9cc31b3a09 bpf: Fix race in btf_resolve_helper_id()
btf_resolve_helper_id() caching logic is a bit racy, since under root the
verifier can verify several programs in parallel. Fix it with READ/WRITE_ONCE.
Fix the type as well, since error is also recorded.

Fixes: a7658e1a41 ("bpf: Check types of arguments passed into helpers")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-15-ast@kernel.org
2019-11-15 23:44:20 +01:00
Alexei Starovoitov
fec56f5890 bpf: Introduce BPF trampoline
Introduce BPF trampoline concept to allow kernel code to call into BPF programs
with practically zero overhead.  The trampoline generation logic is
architecture dependent.  It's converting native calling convention into BPF
calling convention.  BPF ISA is 64-bit (even on 32-bit architectures). The
registers R1 to R5 are used to pass arguments into BPF functions. The main BPF
program accepts only single argument "ctx" in R1. Whereas CPU native calling
convention is different. x86-64 is passing first 6 arguments in registers
and the rest on the stack. x86-32 is passing first 3 arguments in registers.
sparc64 is passing first 6 in registers. And so on.

The trampolines between BPF and kernel already exist.  BPF_CALL_x macros in
include/linux/filter.h statically compile trampolines from BPF into kernel
helpers. They convert up to five u64 arguments into kernel C pointers and
integers. On 64-bit architectures this BPF_to_kernel trampolines are nops. On
32-bit architecture they're meaningful.

The opposite job kernel_to_BPF trampolines is done by CAST_TO_U64 macros and
__bpf_trace_##call() shim functions in include/trace/bpf_probe.h. They convert
kernel function arguments into array of u64s that BPF program consumes via
R1=ctx pointer.

This patch set is doing the same job as __bpf_trace_##call() static
trampolines, but dynamically for any kernel function. There are ~22k global
kernel functions that are attachable via nop at function entry. The function
arguments and types are described in BTF.  The job of btf_distill_func_proto()
function is to extract useful information from BTF into "function model" that
architecture dependent trampoline generators will use to generate assembly code
to cast kernel function arguments into array of u64s.  For example the kernel
function eth_type_trans has two pointers. They will be casted to u64 and stored
into stack of generated trampoline. The pointer to that stack space will be
passed into BPF program in R1. On x86-64 such generated trampoline will consume
16 bytes of stack and two stores of %rdi and %rsi into stack. The verifier will
make sure that only two u64 are accessed read-only by BPF program. The verifier
will also recognize the precise type of the pointers being accessed and will
not allow typecasting of the pointer to a different type within BPF program.

The tracing use case in the datacenter demonstrated that certain key kernel
functions have (like tcp_retransmit_skb) have 2 or more kprobes that are always
active.  Other functions have both kprobe and kretprobe.  So it is essential to
keep both kernel code and BPF programs executing at maximum speed. Hence
generated BPF trampoline is re-generated every time new program is attached or
detached to maintain maximum performance.

To avoid the high cost of retpoline the attached BPF programs are called
directly. __bpf_prog_enter/exit() are used to support per-program execution
stats.  In the future this logic will be optimized further by adding support
for bpf_stats_enabled_key inside generated assembly code. Introduction of
preemptible and sleepable BPF programs will completely remove the need to call
to __bpf_prog_enter/exit().

Detach of a BPF program from the trampoline should not fail. To avoid memory
allocation in detach path the half of the page is used as a reserve and flipped
after each attach/detach. 2k bytes is enough to call 40+ BPF programs directly
which is enough for BPF tracing use cases. This limit can be increased in the
future.

BPF_TRACE_FENTRY programs have access to raw kernel function arguments while
BPF_TRACE_FEXIT programs have access to kernel return value as well. Often
kprobe BPF program remembers function arguments in a map while kretprobe
fetches arguments from a map and analyzes them together with return value.
BPF_TRACE_FEXIT accelerates this typical use case.

Recursion prevention for kprobe BPF programs is done via per-cpu
bpf_prog_active counter. In practice that turned out to be a mistake. It
caused programs to randomly skip execution. The tracing tools missed results
they were looking for. Hence BPF trampoline doesn't provide builtin recursion
prevention. It's a job of BPF program itself and will be addressed in the
follow up patches.

BPF trampoline is intended to be used beyond tracing and fentry/fexit use cases
in the future. For example to remove retpoline cost from XDP programs.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-5-ast@kernel.org
2019-11-15 23:41:51 +01:00
Alexei Starovoitov
5964b2000f bpf: Add bpf_arch_text_poke() helper
Add bpf_arch_text_poke() helper that is used by BPF trampoline logic to patch
nops/calls in kernel text into calls into BPF trampoline and to patch
calls/nops inside BPF programs too.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-4-ast@kernel.org
2019-11-15 23:41:28 +01:00
Ilya Leoshkevich
b7b3fc8dd9 bpf: Support doubleword alignment in bpf_jit_binary_alloc
Currently passing alignment greater than 4 to bpf_jit_binary_alloc does
not work: in such cases it silently aligns only to 4 bytes.

On s390, in order to load a constant from memory in a large (>512k) BPF
program, one must use lgrl instruction, whose memory operand must be
aligned on an 8-byte boundary.

This patch makes it possible to request 8-byte alignment from
bpf_jit_binary_alloc, and also makes it issue a warning when an
unsupported alignment is requested.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191115123722.58462-1-iii@linux.ibm.com
2019-11-15 22:25:00 +01:00
Wolfram Sang
9af433840b i2c: remove helpers for ref-counting clients
There are no in-tree users of these helpers anymore, and there
shouldn't. Most use cases went away once the driver model started to
refcount for us. There have been users like the media subsystem, but
they all switched to better refcounting methods meanwhile. Media did
this in 2008. Last user (IPMI) left 2018. Remove this cruft.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Luca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
2019-11-15 22:04:48 +01:00