Ivan Khoronzhuk [Fri, 11 Oct 2019 00:28:02 +0000 (03:28 +0300)]
samples/bpf: Use own flags but not HOSTCFLAGS
While compiling natively, the host's cflags and ldflags are equal to
ones used from HOSTCFLAGS and HOSTLDFLAGS. When cross compiling it
should have own, used for target arch. While verification, for arm,
arm64 and x86_64 the following flags were used always:
So, add them as they were verified and used before adding
Makefile.target and lets omit "-fomit-frame-pointer" as were proposed
while review, as no sense in such optimization for samples.
Ivan Khoronzhuk [Fri, 11 Oct 2019 00:28:01 +0000 (03:28 +0300)]
samples/bpf: Base target programs rules on Makefile.target
The main reason for that - HOSTCC and CC have different aims.
HOSTCC is used to build programs running on host, that can
cross-comple target programs with CC. It was tested for arm and arm64
cross compilation, based on linaro toolchain, but should work for
others.
So, in order to split cross compilation (CC) with host build (HOSTCC),
lets base samples on Makefile.target. It allows to cross-compile
samples/bpf programs with CC while auxialry tools running on host
built with HOSTCC.
Ivan Khoronzhuk [Fri, 11 Oct 2019 00:28:00 +0000 (03:28 +0300)]
samples/bpf: Add makefile.target for separate CC target build
The Makefile.target is added only and will be used in
sample/bpf/Makefile later in order to switch cross-compiling to CC
from HOSTCC environment.
The HOSTCC is supposed to build binaries and tools running on the host
afterwards, in order to simplify build or so, like "fixdep" or else.
In case of cross compiling "fixdep" is executed on host when the rest
samples should run on target arch. In order to build binaries for
target arch with CC and tools running on host with HOSTCC, lets add
Makefile.target for simplicity, having definition and routines similar
to ones, used in script/Makefile.host. This allows later add
cross-compilation to samples/bpf with minimum changes.
The tprog stands for target programs built with CC.
Makefile.target contains only stuff needed for samples/bpf, potentially
can be reused later and now needed only for unblocking tricky
samples/bpf cross compilation.
Ivan Khoronzhuk [Fri, 11 Oct 2019 00:27:59 +0000 (03:27 +0300)]
samples/bpf: Drop unnecessarily inclusion for bpf_load
Drop inclusion for bpf_load -I$(objtree)/usr/include as it is
included for all objects anyway, with above line:
KBUILD_HOSTCFLAGS += -I$(objtree)/usr/include
Ivan Khoronzhuk [Fri, 11 Oct 2019 00:27:58 +0000 (03:27 +0300)]
samples/bpf: Use __LINUX_ARM_ARCH__ selector for arm
For arm, -D__LINUX_ARM_ARCH__=X is min version used as instruction
set selector and is absolutely required while parsing some parts of
headers. It's present in KBUILD_CFLAGS but not in autoconf.h, so let's
retrieve it from and add to programs cflags. In another case errors
like "SMP is not supported" for armv7 and bunch of other errors are
issued resulting to incorrect final object.
Ivan Khoronzhuk [Fri, 11 Oct 2019 00:27:56 +0000 (03:27 +0300)]
samples/bpf: Use --target from cross-compile
For cross compiling the target triple can be inherited from
cross-compile prefix as it's done in CLANG_FLAGS from kernel makefile.
So copy-paste this decision from kernel Makefile.
Don't list userspace "cookie_uid_helper_example" object in list for
bpf objects.
'always' target is used for listing bpf programs, but
'cookie_uid_helper_example.o' is a user space ELF file, and covered
by rule `per_socket_stats_example`, so shouldn't be in 'always'.
Let us remove `always += cookie_uid_helper_example.o`, which avoids
breaking cross compilation due to mismatched includes.
Andrii Nakryiko [Fri, 11 Oct 2019 03:29:01 +0000 (20:29 -0700)]
libbpf: Handle invalid typedef emitted by old GCC
Old GCC versions are producing invalid typedef for __gnuc_va_list
pointing to void. Special-case this and emit valid:
typedef __builtin_va_list __gnuc_va_list;
Reported-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20191011032901.452042-1-andriin@fb.com
Andrii Nakryiko [Fri, 11 Oct 2019 02:38:47 +0000 (19:38 -0700)]
libbpf: Generate more efficient BPF_CORE_READ code
Existing BPF_CORE_READ() macro generates slightly suboptimal code. If
there are intermediate pointers to be read, initial source pointer is
going to be assigned into a temporary variable and then temporary
variable is going to be uniformly used as a "source" pointer for all
intermediate pointer reads. Schematically (ignoring all the type casts),
BPF_CORE_READ(s, a, b, c) is expanded into:
({
const void *__t = src;
bpf_probe_read(&__t, sizeof(*__t), &__t->a);
bpf_probe_read(&__t, sizeof(*__t), &__t->b);
This initial `__t = src` makes calls more uniform, but causes slightly
less optimal register usage sometimes when compiled with Clang. This can
cascase into, e.g., more register spills.
This patch fixes this issue by generating more optimal sequence:
({
const void *__t;
bpf_probe_read(&__t, sizeof(*__t), &src->a); /* <-- src here */
bpf_probe_read(&__t, sizeof(*__t), &__t->b);
Andrii Nakryiko [Fri, 11 Oct 2019 17:20:53 +0000 (10:20 -0700)]
bpf: Fix cast to pointer from integer of different size warning
Fix "warning: cast to pointer from integer of different size" when
casting u64 addr to void *.
Fixes: 46a1145a9048 ("bpf: Track contents of read-only maps as scalars") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191011172053.2980619-1-andriin@fb.com
Jakub Sitnicki [Fri, 11 Oct 2019 08:29:46 +0000 (10:29 +0200)]
selftests/bpf: Check that flow dissector can be re-attached
Make sure a new flow dissector program can be attached to replace the old
one with a single syscall. Also check that attaching the same program twice
is prohibited.
Jakub Sitnicki [Fri, 11 Oct 2019 08:29:45 +0000 (10:29 +0200)]
flow_dissector: Allow updating the flow dissector program atomically
It is currently not possible to detach the flow dissector program and
attach a new one in an atomic fashion, that is with a single syscall.
Attempts to do so will be met with EEXIST error.
This makes updates to flow dissector program hard. Traffic steering that
relies on BPF-powered flow dissection gets disrupted while old program has
been already detached but the new one has not been attached yet.
There is also a window of opportunity to attach a flow dissector to a
non-root namespace while updating the root flow dissector, thus blocking
the update.
Lastly, the behavior is inconsistent with cgroup BPF programs, which can be
replaced with a single bpf(BPF_PROG_ATTACH, ...) syscall without any
restrictions.
Allow attaching a new flow dissector program when another one is already
present with a restriction that it can't be the same program.
Daniel Borkmann [Thu, 10 Oct 2019 23:49:16 +0000 (01:49 +0200)]
Merge branch 'bpf-romap-known-scalars'
Andrii Nakryiko says:
====================
With BPF maps supporting direct map access (currently, array_map w/ single
element, used for global data) that are read-only both from system call and
BPF side, it's possible for BPF verifier to track its contents as known
constants.
Now it's possible for user-space control app to pre-initialize read-only map
(e.g., for .rodata section) with user-provided flags and parameters and rely
on BPF verifier to detect and eliminate dead code resulting from specific
combination of input parameters.
v1->v2:
- BPF_F_RDONLY means nothing, stick to just map->frozen (Daniel);
- stick to passing just offset into map_direct_value_addr (Martin).
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add tests checking that verifier does proper constant propagation for
read-only maps. If constant propagation didn't work, skipp_loop and
part_loop BPF programs would be rejected due to BPF verifier otherwise
not being able to prove they ever complete. With constant propagation,
though, they are succesfully validated as properly terminating loops.
Andrii Nakryiko [Wed, 9 Oct 2019 20:14:57 +0000 (13:14 -0700)]
bpf: Track contents of read-only maps as scalars
Maps that are read-only both from BPF program side and user space side
have their contents constant, so verifier can track referenced values
precisely and use that knowledge for dead code elimination, branch
pruning, etc. This patch teaches BPF verifier how to do this.
Ilya Maximets [Wed, 9 Oct 2019 16:49:29 +0000 (18:49 +0200)]
libbpf: Fix passing uninitialized bytes to setsockopt
'struct xdp_umem_reg' has 4 bytes of padding at the end that makes
valgrind complain about passing uninitialized stack memory to the
syscall:
Syscall param socketcall.setsockopt() points to uninitialised byte(s)
at 0x4E7AB7E: setsockopt (in /usr/lib64/libc-2.29.so)
by 0x4BDE035: xsk_umem__create@@LIBBPF_0.0.4 (xsk.c:172)
Uninitialised value was created by a stack allocation
at 0x4BDDEBA: xsk_umem__create@@LIBBPF_0.0.4 (xsk.c:140)
Padding bytes appeared after introducing of a new 'flags' field.
memset() is required to clear them.
====================
Fix BTF-to-C logic of handling padding at the end of a struct. Fix existing
test that should have captured this. Also move test_btf_dump into a test_progs
test to leverage common infrastructure.
====================
Andrii Nakryiko [Tue, 8 Oct 2019 23:10:08 +0000 (16:10 -0700)]
selftests/bpf: Fix btf_dump padding test case
Existing padding test case for btf_dump has a good test that was
supposed to test padding generation at the end of a struct, but its
expected output was specified incorrectly. Fix this.
Andrii Nakryiko [Tue, 8 Oct 2019 23:10:06 +0000 (16:10 -0700)]
libbpf: Fix struct end padding in btf_dump
Fix a case where explicit padding at the end of a struct is necessary
due to non-standart alignment requirements of fields (which BTF doesn't
capture explicitly).
Fixes: b653ca9bf78a ("libbpf: add btf_dump API for BTF-to-C conversion") Reported-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20191008231009.2991130-2-andriin@fb.com
Daniel Borkmann [Tue, 8 Oct 2019 21:16:04 +0000 (23:16 +0200)]
Merge branch 'bpf-libbpf-helpers'
Andrii Nakryiko says:
====================
This patch set makes bpf_helpers.h and bpf_endian.h a part of libbpf itself
for consumption by user BPF programs, not just selftests. It also splits off
tracing helpers into bpf_tracing.h, which also becomes part of libbpf. Some of
the legacy stuff (BPF_ANNOTATE_KV_PAIR, load_{byte,half,word}, bpf_map_def
with unsupported fields, etc, is extracted into selftests-only bpf_legacy.h.
All the selftests and samples are switched to use libbpf's headers and
selftests' ones are removed.
As part of this patch set we also add BPF_CORE_READ variadic macros, that are
simplifying BPF CO-RE reads, especially the ones that have to follow few
pointers. E.g., what in non-BPF world (and when using BCC) would be:
int x = s->a->b.c->d; /* s, a, and b.c are pointers */
Today would have to be written using explicit bpf_probe_read() calls as:
void *t;
int x;
bpf_probe_read(&t, sizeof(t), s->a);
bpf_probe_read(&t, sizeof(t), ((struct b *)t)->b.c);
bpf_probe_read(&x, sizeof(x), ((struct c *)t)->d);
This is super inconvenient and distracts from program logic a lot. Now, with
added BPF_CORE_READ() macros, you can write the above as:
int x = BPF_CORE_READ(s, a, b.c, d);
Up to 9 levels of pointer chasing are supported, which should be enough for
any practical purpose, hopefully, without adding too much boilerplate macro
definitions (though there is admittedly some, given how variadic and recursive
C macro have to be implemented).
There is also BPF_CORE_READ_INTO() variant, which relies on caller to allocate
space for result:
int x;
BPF_CORE_READ_INTO(&x, s, a, b.c, d);
Result of last bpf_probe_read() call in the chain of calls is the result of
BPF_CORE_READ_INTO(). If any intermediate bpf_probe_read() aall fails, then
all the subsequent ones will fail too, so this is sufficient to know whether
overall "operation" succeeded or not. No short-circuiting of bpf_probe_read()s
is done, though.
BPF_CORE_READ_STR_INTO() is added as well, which differs from
BPF_CORE_READ_INTO() only in that last bpf_probe_read() call (to read final
field after chasing pointers) is replaced with bpf_probe_read_str(). Result of
bpf_probe_read_str() is returned as a result of BPF_CORE_READ_STR_INTO() macro
itself, so that applications can track return code and/or length of read
string.
Patch set outline:
- patch #1 undoes previously added GCC-specific bpf-helpers.h include;
- patch #2 splits off legacy stuff we don't want to carry over;
- patch #3 adjusts CO-RE reloc tests to avoid subsequent naming conflict with
BPF_CORE_READ;
- patch #4 splits off bpf_tracing.h;
- patch #5 moves bpf_{helpers,endian,tracing}.h and bpf_helper_defs.h
generation into libbpf and adjusts Makefiles to include libbpf for header
search;
- patch #6 adds variadic BPF_CORE_READ() macro family, as described above;
- patch #7 adds tests to verify all possible levels of pointer nestedness for
BPF_CORE_READ(), as well as correctness test for BPF_CORE_READ_STR_INTO().
v4->v5:
- move BPF_CORE_READ() stuff into bpf_core_read.h header (Alexei);
v3->v4:
- rebase on latest bpf-next master;
- bpf_helper_defs.h generation is moved into libbpf's Makefile;
v2->v3:
- small formatting fixes and macro () fixes (Song);
v1->v2:
- fix CO-RE reloc tests before bpf_helpers.h move (Song);
- split off legacy stuff we don't want to carry over (Daniel, Toke);
- split off bpf_tracing.h (Daniel);
- fix samples/bpf build (assuming other fixes are applied);
- switch remaining maps either to bpf_map_def_legacy or BTF-defined maps;
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Andrii Nakryiko [Tue, 8 Oct 2019 17:59:42 +0000 (10:59 -0700)]
selftests/bpf: Add BPF_CORE_READ and BPF_CORE_READ_STR_INTO macro tests
Validate BPF_CORE_READ correctness and handling of up to 9 levels of
nestedness using cyclic task->(group_leader->)*->tgid chains.
Also add a test of maximum-dpeth BPF_CORE_READ_STR_INTO() macro.
Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-8-andriin@fb.com
Add few macros simplifying BCC-like multi-level probe reads, while also
emitting CO-RE relocations for each read.
Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-7-andriin@fb.com
Andrii Nakryiko [Tue, 8 Oct 2019 17:59:40 +0000 (10:59 -0700)]
libbpf: Move bpf_{helpers, helper_defs, endian, tracing}.h into libbpf
Move bpf_helpers.h, bpf_tracing.h, and bpf_endian.h into libbpf. Move
bpf_helper_defs.h generation into libbpf's Makefile. Ensure all those
headers are installed along the other libbpf headers. Also, adjust
selftests and samples include path to include libbpf now.
Andrii Nakryiko [Tue, 8 Oct 2019 17:59:39 +0000 (10:59 -0700)]
selftests/bpf: Split off tracing-only helpers into bpf_tracing.h
Split-off PT_REGS-related helpers into bpf_tracing.h header. Adjust
selftests and samples to include it where necessary.
Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-5-andriin@fb.com
Andrii Nakryiko [Tue, 8 Oct 2019 17:59:38 +0000 (10:59 -0700)]
selftests/bpf: Adjust CO-RE reloc tests for new bpf_core_read() macro
To allow adding a variadic BPF_CORE_READ macro with slightly different
syntax and semantics, define CORE_READ in CO-RE reloc tests, which is
a thin wrapper around low-level bpf_core_read() macro, which in turn is
just a wrapper around bpf_probe_read().
Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-4-andriin@fb.com
Andrii Nakryiko [Tue, 8 Oct 2019 17:59:37 +0000 (10:59 -0700)]
selftests/bpf: samples/bpf: Split off legacy stuff from bpf_helpers.h
Split off few legacy things from bpf_helpers.h into separate
bpf_legacy.h file:
- load_{byte|half|word};
- remove extra inner_idx and numa_node fields from bpf_map_def and
introduce bpf_map_def_legacy for use in samples;
- move BPF_ANNOTATE_KV_PAIR into bpf_legacy.h.
Adjust samples and selftests accordingly by either including
bpf_legacy.h and using bpf_map_def_legacy, or switching to BTF-defined
maps altogether.
Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-3-andriin@fb.com
Having GCC provide its own bpf-helper.h is not the right approach and is
going to be changed. Undo bpf_helpers.h change before moving
bpf_helpers.h into libbpf.
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: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20191008175942.1769476-2-andriin@fb.com
Daniel T. Lee [Mon, 7 Oct 2019 17:21:17 +0000 (02:21 +0900)]
samples: bpf: Add max_pckt_size option at xdp_adjust_tail
Currently, at xdp_adjust_tail_kern.c, MAX_PCKT_SIZE is limited
to 600. To make this size flexible, static global variable
'max_pcktsz' is added.
By updating new packet size from the user space, xdp_adjust_tail_kern.o
will use this value as a new max packet size.
This static global variable can be accesible from .data section with
bpf_object__find_map* from user space, since it is considered as
internal map (accessible with .bss/.data/.rodata suffix).
If no '-P <MAX_PCKT_SIZE>' option is used, the size of maximum packet
will be 600 as a default.
For clarity, change the helper to fetch map from 'bpf_map__next'
to 'bpf_object__find_map_fd_by_name'. Also, changed the way to
test prog_fd, map_fd from '!= 0' to '< 0', since fd could be 0
when stdin is closed.
====================
While having a per-net-ns flow dissector programs is convenient for
testing, security-wise it's better to have only one vetted global
flow dissector implementation.
Let's have a convention that when BPF flow dissector is installed
in the root namespace, child namespaces can't override it.
The intended use-case is to attach global BPF flow dissector
early from the init scripts/systemd. Attaching global dissector
is prohibited if some non-root namespace already has flow dissector
attached. Also, attaching to non-root namespace is prohibited
when there is flow dissector attached to the root namespace.
v3:
* drop extra check and empty line (Andrii Nakryiko)
v2:
* EPERM -> EEXIST (Song Liu)
* Make sure we don't have dissector attached to non-root namespaces
when attaching the global one (Andrii Nakryiko)
====================
selftests/bpf: add test for BPF flow dissector in the root namespace
Make sure non-root namespaces get an error if root flow dissector is
attached.
Cc: Petar Penkov <ppenkov@google.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf/flow_dissector: add mode to enforce global BPF flow dissector
Always use init_net flow dissector BPF program if it's attached and fall
back to the per-net namespace one. Also, deny installing new programs if
there is already one attached to the root namespace.
Users can still detach their BPF programs, but can't attach any
new ones (-EEXIST).
Cc: Petar Penkov <ppenkov@google.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Andrii Nakryiko [Mon, 7 Oct 2019 22:56:04 +0000 (15:56 -0700)]
bpftool: Fix bpftool build by switching to bpf_object__open_file()
As part of libbpf in d23bba12f976 ("libbpf: stop enforcing kern_version,
populate it for users") non-LIBBPF_API __bpf_object__open_xattr() API
was removed from libbpf.h header. This broke bpftool, which relied on
that function. This patch fixes the build by switching to newly added
bpf_object__open_file() which provides the same capabilities, but is
official and future-proof API.
v1->v2:
- fix prog_type shadowing (Stanislav).
Fixes: d23bba12f976 ("libbpf: stop enforcing kern_version, populate it for users") Reported-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20191007225604.2006146-1-andriin@fb.com
Andrii Nakryiko [Mon, 7 Oct 2019 20:41:49 +0000 (13:41 -0700)]
selftests/bpf: Fix dependency ordering for attach_probe test
Current Makefile dependency chain is not strict enough and allows
test_attach_probe.o to be built before test_progs's
prog_test/attach_probe.o is built, which leads to assembler complaining
about missing included binary.
This patch is a minimal fix to fix this issue by enforcing that
test_attach_probe.o (BPF object file) is built before
prog_tests/attach_probe.c is attempted to be compiled.
====================
This patch set adds ability to auto-generate list of BPF helper definitions.
It relies on existing scripts/bpf_helpers_doc.py and include/uapi/linux/bpf.h
having a well-defined set of comments. bpf_helper_defs.h contains all BPF
helper signatures which stay in sync with latest bpf.h UAPI. This
auto-generated header is included from bpf_helpers.h, while all previously
hand-written BPF helper definitions are simultaneously removed in patch #3.
The end result is less manually maintained and redundant boilerplate code,
while also more consistent and well-documented set of BPF helpers. Generated
helper definitions are completely independent from a specific bpf.h on
a target system, because it doesn't use BPF_FUNC_xxx enums.
v3->v4:
- instead of libbpf's Makefile, integrate with selftest/bpf's Makefile (Alexei);
Using cscope and/or TAGS files for navigating the source code is useful.
Add simple targets to the Makefile to generate the index files for both
tools.
====================
Add bpf_object__open_file() and bpf_object__open_mem() APIs that use a new
approach to providing future-proof non-ABI-breaking API changes. It relies on
APIs accepting optional self-describing "opts" struct, containing its own
size, filled out and provided by potentially outdated (as well as
newer-than-libbpf) user application. A set of internal helper macros
(OPTS_VALID, OPTS_HAS, and OPTS_GET) streamline and simplify a graceful
handling forward and backward compatibility for user applications dynamically
linked against different versions of libbpf shared library.
Users of libbpf are provided with convenience macro LIBBPF_OPTS that takes
care of populating correct structure size and zero-initializes options struct,
which helps avoid obscure issues of unitialized padding. Uninitialized padding
in a struct might turn into garbage-populated new fields understood by future
versions of libbpf.
Patch #1 removes enforcement of kern_version in libbpf and always populates
correct one on behalf of users.
Patch #2 defines necessary infrastructure for options and two new open APIs
relying on it.
Patch #3 fixes bug in bpf_object__name().
Patch #4 switches two of test_progs' tests to use new APIs as a validation
that they work as expected.
v2->v3:
- fix LIBBPF_OPTS() to ensure zero-initialization of padded bytes;
- pass through name override and relaxed maps flag for open_file() (Toke);
- fix bpf_object__name() to actually return object name;
- don't bother parsing and verifying version section (John);
v1->v2:
- use better approach for tracking last field in opts struct;
- convert few tests to new APIs for validation;
- fix bug with using offsetof(last_field) instead of offsetofend(last_field).
====================
Andrii Nakryiko [Fri, 4 Oct 2019 22:40:37 +0000 (15:40 -0700)]
selftests/bpf: switch tests to new bpf_object__open_{file, mem}() APIs
Verify new bpf_object__open_mem() and bpf_object__open_file() APIs work
as expected by switching test_attach_probe test to use embedded BPF
object and bpf_object__open_mem() and test_reference_tracking to
bpf_object__open_file().
Add new set of bpf_object__open APIs using new approach to optional
parameters extensibility allowing simpler ABI compatibility approach.
This patch demonstrates an approach to implementing libbpf APIs that
makes it easy to extend existing APIs with extra optional parameters in
such a way, that ABI compatibility is preserved without having to do
symbol versioning and generating lots of boilerplate code to handle it.
To facilitate succinct code for working with options, add OPTS_VALID,
OPTS_HAS, and OPTS_GET macros that hide all the NULL, size, and zero
checks.
Additionally, newly added libbpf APIs are encouraged to follow similar
pattern of having all mandatory parameters as formal function parameters
and always have optional (NULL-able) xxx_opts struct, which should
always have real struct size as a first field and the rest would be
optional parameters added over time, which tune the behavior of existing
API, if specified by user.
Andrii Nakryiko [Fri, 4 Oct 2019 22:40:34 +0000 (15:40 -0700)]
libbpf: stop enforcing kern_version, populate it for users
Kernel version enforcement for kprobes/kretprobes was removed from
5.0 kernel in 1a4860981cdd ("bpf: remove useless version check for prog load").
Since then, BPF programs were specifying SEC("version") just to please
libbpf. We should stop enforcing this in libbpf, if even kernel doesn't
care. Furthermore, libbpf now will pre-populate current kernel version
of the host system, in case we are still running on old kernel.
This patch also removes __bpf_object__open_xattr from libbpf.h, as
nothing in libbpf is relying on having it in that header. That function
was never exported as LIBBPF_API and even name suggests its internal
version. So this should be safe to remove, as it doesn't break ABI.
Andrii Nakryiko [Fri, 4 Oct 2019 04:02:11 +0000 (21:02 -0700)]
libbpf: Fix BTF-defined map's __type macro handling of arrays
Due to a quirky C syntax of declaring pointers to array or function
prototype, existing __type() macro doesn't work with map key/value types
that are array or function prototype. One has to create a typedef first
and use it to specify key/value type for a BPF map. By using typeof(),
pointer to type is now handled uniformly for all kinds of types. Convert
one of self-tests as a demonstration.
Daniel Borkmann [Wed, 2 Oct 2019 23:45:11 +0000 (01:45 +0200)]
bpf, x86: Small optimization in comparing against imm0
Replace 'cmp reg, 0' with 'test reg, reg' for comparisons against
zero. Saves 1 byte of instruction encoding per occurrence. The flag
results of test 'reg, reg' are identical to 'cmp reg, 0' in all
cases except for AF which we don't use/care about. In terms of
macro-fusibility in combination with a subsequent conditional jump
instruction, both have the same properties for the jumps used in
the JIT translation. For example, same JITed Cilium program can
shrink a bit from e.g. 12,455 to 12,317 bytes as tests with 0 are
used quite frequently.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com>
Ivan Khoronzhuk [Wed, 2 Oct 2019 12:04:04 +0000 (15:04 +0300)]
selftests/bpf: Correct path to include msg + path
The "path" buf is supposed to contain path + printf msg up to 24 bytes.
It will be cut anyway, but compiler generates truncation warns like:
"
samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c: In
function ‘setup_cgroup_environment’:
samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:52:34:
warning: ‘/cgroup.controllers’ directive output may be truncated
writing 19 bytes into a region of size between 1 and 4097
[-Wformat-truncation=]
snprintf(path, sizeof(path), "%s/cgroup.controllers", cgroup_path);
^~~~~~~~~~~~~~~~~~~
samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:52:2:
note: ‘snprintf’ output between 20 and 4116 bytes into a destination
of size 4097
snprintf(path, sizeof(path), "%s/cgroup.controllers", cgroup_path);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:72:34:
warning: ‘/cgroup.subtree_control’ directive output may be truncated
writing 23 bytes into a region of size between 1 and 4097
[-Wformat-truncation=]
snprintf(path, sizeof(path), "%s/cgroup.subtree_control",
^~~~~~~~~~~~~~~~~~~~~~~
cgroup_path);
samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:72:2:
note: ‘snprintf’ output between 24 and 4120 bytes into a destination
of size 4097
snprintf(path, sizeof(path), "%s/cgroup.subtree_control",
cgroup_path);
"
In order to avoid warns, lets decrease buf size for cgroup workdir on
24 bytes with assumption to include also "/cgroup.subtree_control" to
the address. The cut will never happen anyway.
Ivan Khoronzhuk [Wed, 2 Oct 2019 12:04:03 +0000 (15:04 +0300)]
selftests/bpf: Add static to enable_all_controllers()
Add static to enable_all_controllers() to get rid from annoying warning
during samples/bpf build:
samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:44:5:
warning: no previous prototype for ‘enable_all_controllers’
[-Wmissing-prototypes]
int enable_all_controllers(char *cgroup_path)
Simon Horman [Mon, 30 Sep 2019 14:03:52 +0000 (16:03 +0200)]
dt-bindings: sh_eth convert bindings to json-schema
Convert Renesas Electronics SH EtherMAC bindings documentation to
json-schema. Also name bindings documentation file according to the compat
string being documented.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Reviewed-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Peter Fink [Mon, 30 Sep 2019 12:04:03 +0000 (14:04 +0200)]
net: usb: ax88179_178a: allow optionally getting mac address from device tree
Adopt and integrate the feature to pass the MAC address via device tree
from asix_device.c (0c7f677) also to other ax88179 based asix chips.
E.g. the bootloader fills in local-mac-address and the driver will then
pick up and use this MAC address.
Signed-off-by: Peter Fink <pfink@christ-es.de> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Tue, 1 Oct 2019 21:47:19 +0000 (14:47 -0700)]
Merge branch 'netdev-altnames'
Jiri Pirko says:
====================
net: introduce alternative names for network interfaces
In the past, there was repeatedly discussed the IFNAMSIZ (16) limit for
netdevice name length. Now when we have PF and VF representors
with port names like "pfXvfY", it became quite common to hit this limit: 0123456789012345
enp131s0f1npf0vf6
enp131s0f1npf0vf22
Udev cannot rename these interfaces out-of-the-box and user needs to
create custom rules to handle them.
Also, udev has multiple schemes of netdev names. From udev code:
* Type of names:
* b<number> - BCMA bus core number
* c<bus_id> - bus id of a grouped CCW or CCW device,
* with all leading zeros stripped [s390]
* o<index>[n<phys_port_name>|d<dev_port>]
* - on-board device index number
* s<slot>[f<function>][n<phys_port_name>|d<dev_port>]
* - hotplug slot index number
* x<MAC> - MAC address
* [P<domain>]p<bus>s<slot>[f<function>][n<phys_port_name>|d<dev_port>]
* - PCI geographical location
* [P<domain>]p<bus>s<slot>[f<function>][u<port>][..][c<config>][i<interface>]
* - USB port number chain
* v<slot> - VIO slot number (IBM PowerVM)
* a<vendor><model>i<instance> - Platform bus ACPI instance id
* i<addr>n<phys_port_name> - Netdevsim bus address and port name
One device can be often renamed by multiple patterns at the
same time (e.g. pci address/mac).
This patchset introduces alternative names for network interfaces.
Main goal is to:
1) Overcome the IFNAMSIZ limitation (altname limitation is 128 bytes)
2) Allow to have multiple names at the same time (multiple udev patterns)
3) Allow to use alternative names as handle for commands
The patchset introduces two new commands to add/delete list of properties.
Currently only alternative names are implemented but the ifrastructure
could be easily extended later on. This is very similar to the list of vlan
and tunnels being added/deleted to/from bridge ports.
See following examples.
$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
-> Add alternative names for dummy0:
$ ip link prop add dummy0 altname someothername
$ ip link prop add dummy0 altname someotherveryveryveryverylongname
$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname someothername
altname someotherveryveryveryverylongname
$ ip link show someotherveryveryveryverylongname
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname someothername
altname someotherveryveryveryverylongname
-> Add bridge brx, add it's alternative name and use alternative names to
do enslavement.
$ ip link add name brx type bridge
$ ip link prop add brx altname mypersonalsuperspecialbridge
$ ip link set someotherveryveryveryverylongname master mypersonalsuperspecialbridge
$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop master brx state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname someothername
altname someotherveryveryveryverylongname
3: brx: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname mypersonalsuperspecialbridge
-> Add ipv4 address to the bridge using alternative name:
$ ip addr add 192.168.0.1/24 dev mypersonalsuperspecialbridge
$ ip addr show mypersonalsuperspecialbridge
3: brx: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname mypersonalsuperspecialbridge
inet 192.168.0.1/24 scope global brx
valid_lft forever preferred_lft forever
-> Delete one of dummy0 alternative names:
$ ip link prop del dummy0 altname someotherveryveryveryverylongname
$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop master brx state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname someothername
3: brx: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname mypersonalsuperspecialbridge
-> Add multiple alternative names at once
$ ip link prop add dummy0 altname a altname b altname c altname d
$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop master brx state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname someothername
altname a
altname b
altname c
altname d
3: brx: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:67:a9:67:46:86 brd ff:ff:ff:ff:ff:ff
altname mypersonalsuperspecialbridge
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
net: rtnetlink: unify the code in __rtnl_newlink get dev with the rest
__rtnl_newlink() code flow is a bit different around tb[IFLA_IFNAME]
processing comparing to the other places. Change that to be unified with
the rest.
Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
net: rtnetlink: add linkprop commands to add and delete alternative ifnames
Add two commands to add and delete list of link properties. Implement
the first property type along - alternative ifnames.
Each net device can have multiple alternative names.
Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
net: introduce name_node struct to be used in hashlist
Introduce name_node structure to hold name of device and put it into
hashlist instead of putting there struct net_device directly. Add a
necessary infrastructure to manipulate the hashlist. This prepares
the code to use the same hashlist for alternative names introduced
later in this set.
Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Julio Faracco [Tue, 1 Oct 2019 14:39:04 +0000 (11:39 -0300)]
net: core: dev: replace state xoff flag comparison by netif_xmit_stopped method
Function netif_schedule_queue() has a hardcoded comparison between queue
state and any xoff flag. This comparison does the same thing as method
netif_xmit_stopped(). In terms of code clarity, it is better. See other
methods like: generic_xdp_tx() and dev_direct_xmit().
Signed-off-by: Julio Faracco <jcfaracco@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Prashant Malani [Tue, 1 Oct 2019 08:35:57 +0000 (01:35 -0700)]
r8152: Factor out OOB link list waits
The same for-loop check for the LINK_LIST_READY bit of an OOB_CTRL
register is used in several places. Factor these out into a single
function to reduce the lines of code.
Change-Id: I20e8f327045a72acc0a83e2d145ae2993ab62915 Signed-off-by: Prashant Malani <pmalani@chromium.org> Reviewed-by: Grant Grundler <grundler@chromium.org> Acked-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1) Sanity check URB networking device parameters to avoid divide by
zero, from Oliver Neukum.
2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
don't work properly. Longer term this needs a better fix tho. From
Vijay Khemka.
3) Small fixes to selftests (use ping when ping6 is not present, etc.)
from David Ahern.
4) Bring back rt_uses_gateway member of struct rtable, it's semantics
were not well understood and trying to remove it broke things. From
David Ahern.
5) Move usbnet snaity checking, ignore endpoints with invalid
wMaxPacketSize. From Bjørn Mork.
6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.
7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
Alex Vesker, and Yevgeny Kliteynik
8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.
9) Fix crash when removing sch_cbs entry while offloading is enabled,
from Vinicius Costa Gomes.
10) Signedness bug fixes, generally in looking at the result given by
of_get_phy_mode() and friends. From Dan Crapenter.
11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.
12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.
13) Fix quantization code in tcp_bbr, from Kevin Yang.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
net: tap: clean up an indentation issue
nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
sk_buff: drop all skb extensions on free and skb scrubbing
tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
Documentation: Clarify trap's description
mlxsw: spectrum: Clear VLAN filters during port initialization
net: ena: clean up indentation issue
NFC: st95hf: clean up indentation issue
net: phy: micrel: add Asym Pause workaround for KSZ9021
net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
ptp: correctly disable flags on old ioctls
lib: dimlib: fix help text typos
net: dsa: microchip: Always set regmap stride to 1
nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
...
Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes)
Merge hugepage allocation updates from David Rientjes:
"We (mostly Linus, Andrea, and myself) have been discussing offlist how
to implement a sane default allocation strategy for hugepages on NUMA
platforms.
With these reverts in place, the page allocator will happily allocate
a remote hugepage immediately rather than try to make a local hugepage
available. This incurs a substantial performance degradation when
memory compaction would have otherwise made a local hugepage
available.
This series reverts those reverts and attempts to propose a more sane
default allocation strategy specifically for hugepages. Andrea
acknowledges this is likely to fix the swap storms that he originally
reported that resulted in the patches that removed __GFP_THISNODE from
hugepage allocations.
The immediate goal is to return 5.3 to the behavior the kernel has
implemented over the past several years so that remote hugepages are
not immediately allocated when local hugepages could have been made
available because the increased access latency is untenable.
The next goal is to introduce a sane default allocation strategy for
hugepages allocations in general regardless of the configuration of
the system so that we prevent thrashing of local memory when
compaction is unlikely to succeed and can prefer remote hugepages over
remote native pages when the local node is low on memory."
Note on timing: this reverts the hugepage VM behavior changes that got
introduced fairly late in the 5.3 cycle, and that fixed a huge
performance regression for certain loads that had been around since
4.18.
Andrea had this note:
"The regression of 4.18 was that it was taking hours to start a VM
where 3.10 was only taking a few seconds, I reported all the details
on lkml when it was finally tracked down in August 2018.
__GFP_THISNODE in MADV_HUGEPAGE made the above enterprise vfio
workload degrade like in the "current upstream" above. And it still
would have been that bad as above until 5.3-rc5"
where the bad behavior ends up happening as you fill up a local node,
and without that change, you'd get into the nasty swap storm behavior
due to compaction working overtime to make room for more memory on the
nodes.
As a result 5.3 got the two performance fix reverts in rc5.
However, David Rientjes then noted that those performance fixes in turn
regressed performance for other loads - although not quite to the same
degree. He suggested reverting the reverts and instead replacing them
with two small changes to how hugepage allocations are done (patch
descriptions rephrased by me):
- "avoid expensive reclaim when compaction may not succeed": just admit
that the allocation failed when you're trying to allocate a huge-page
and compaction wasn't successful.
- "allow hugepage fallback to remote nodes when madvised": when that
node-local huge-page allocation failed, retry without forcing the
local node.
but by then I judged it too late to replace the fixes for a 5.3 release.
So 5.3 was released with behavior that harked back to the pre-4.18 logic.
But now we're in the merge window for 5.4, and we can see if this
alternate model fixes not just the horrendous swap storm behavior, but
also restores the performance regression that the late reverts caused.
Fingers crossed.
* emailed patches from David Rientjes <rientjes@google.com>:
mm, page_alloc: allow hugepage fallback to remote nodes when madvised
mm, page_alloc: avoid expensive reclaim when compaction may not succeed
Revert "Revert "Revert "mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask""
Revert "Revert "mm, thp: restore node-local hugepage allocations""
David Rientjes [Wed, 4 Sep 2019 19:54:25 +0000 (12:54 -0700)]
mm, page_alloc: allow hugepage fallback to remote nodes when madvised
For systems configured to always try hard to allocate transparent
hugepages (thp defrag setting of "always") or for memory that has been
explicitly madvised to MADV_HUGEPAGE, it is often better to fallback to
remote memory to allocate the hugepage if the local allocation fails
first.
The point is to allow the initial call to __alloc_pages_node() to attempt
to defragment local memory to make a hugepage available, if possible,
rather than immediately fallback to remote memory. Local hugepages will
always have a better access latency than remote (huge)pages, so an attempt
to make a hugepage available locally is always preferred.
If memory compaction cannot be successful locally, however, it is likely
better to fallback to remote memory. This could take on two forms: either
allow immediate fallback to remote memory or do per-zone watermark checks.
It would be possible to fallback only when per-zone watermarks fail for
order-0 memory, since that would require local reclaim for all subsequent
faults so remote huge allocation is likely better than thrashing the local
zone for large workloads.
In this case, it is assumed that because the system is configured to try
hard to allocate hugepages or the vma is advised to explicitly want to try
hard for hugepages that remote allocation is better when local allocation
and memory compaction have both failed.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Stefan Priebe - Profihost AG <s.priebe@profihost.ag> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Wed, 4 Sep 2019 19:54:22 +0000 (12:54 -0700)]
mm, page_alloc: avoid expensive reclaim when compaction may not succeed
Memory compaction has a couple significant drawbacks as the allocation
order increases, specifically:
- isolate_freepages() is responsible for finding free pages to use as
migration targets and is implemented as a linear scan of memory
starting at the end of a zone,
- failing order-0 watermark checks in memory compaction does not account
for how far below the watermarks the zone actually is: to enable
migration, there must be *some* free memory available. Per the above,
watermarks are not always suffficient if isolate_freepages() cannot
find the free memory but it could require hundreds of MBs of reclaim to
even reach this threshold (read: potentially very expensive reclaim with
no indication compaction can be successful), and
- if compaction at this order has failed recently so that it does not even
run as a result of deferred compaction, looping through reclaim can often
be pointless.
For hugepage allocations, these are quite substantial drawbacks because
these are very high order allocations (order-9 on x86) and falling back to
doing reclaim can potentially be *very* expensive without any indication
that compaction would even be successful.
Reclaim itself is unlikely to free entire pageblocks and certainly no
reliance should be put on it to do so in isolation (recall lumpy reclaim).
This means we should avoid reclaim and simply fail hugepage allocation if
compaction is deferred.
It is also not helpful to thrash a zone by doing excessive reclaim if
compaction may not be able to access that memory. If order-0 watermarks
fail and the allocation order is sufficiently large, it is likely better
to fail the allocation rather than thrashing the zone.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Stefan Priebe - Profihost AG <s.priebe@profihost.ag> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit af95e50adb9d ("Revert "mm, thp: restore node-local hugepage
allocations"") is reverted in this series, it is better to restore the
previous 5.2 behavior between the thp allocation and the page allocator
rather than to attempt any consolidation or cleanup for a policy that is
now reverted. It's less risky during an rc cycle and subsequent patches
in this series further modify the same policy that the pre-5.3 behavior
implements.
Consolidation and cleanup can be done subsequent to a sane default page
allocation strategy, so this patch reverts a cleanup done on a strategy
that is now reverted and thus is the least risky option.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Stefan Priebe - Profihost AG <s.priebe@profihost.ag> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commit references the original intended semantic for MADV_HUGEPAGE
which has subsequently taken on three unique purposes:
- enables or disables thp for a range of memory depending on the system's
config (is thp "enabled" set to "always" or "madvise"),
- determines the synchronous compaction behavior for thp allocations at
fault (is thp "defrag" set to "always", "defer+madvise", or "madvise"),
and
- reverts a previous MADV_NOHUGEPAGE (there is no madvise mode to only
clear previous hugepage advice).
These are the three purposes that currently exist in 5.2 and over the
past several years that userspace has been written around. Adding a
NUMA locality preference adds a fourth dimension to an already conflated
advice mode.
Based on the semantic that MADV_HUGEPAGE has provided over the past
several years, there exist workloads that use the tunable based on these
principles: specifically that the allocation should attempt to
defragment a local node before falling back. It is agreed that remote
hugepages typically (but not always) have a better access latency than
remote native pages, although on Naples this is at parity for
intersocket.
The revert commit that this patch reverts allows hugepage allocation to
immediately allocate remotely when local memory is fragmented. This is
contrary to the semantic of MADV_HUGEPAGE over the past several years:
that is, memory compaction should be attempted locally before falling
back.
The performance degradation of remote hugepages over local hugepages on
Rome, for example, is 53.5% increased access latency. For this reason,
the goal is to revert back to the 5.2 and previous behavior that would
attempt local defragmentation before falling back. With the patch that
is reverted by this patch, we see performance degradations at the tail
because the allocator happily allocates the remote hugepage rather than
even attempting to make a local hugepage available.
zone_reclaim_mode is not a solution to this problem since it does not
only impact hugepage allocations but rather changes the memory
allocation strategy for *all* page allocations.
Signed-off-by: David Rientjes <rientjes@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Stefan Priebe - Profihost AG <s.priebe@profihost.ag> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'powerpc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"An assortment of fixes that were either missed by me, or didn't arrive
quite in time for the first v5.4 pull.
- Most notable is a fix for an issue with tlbie (broadcast TLB
invalidation) on Power9, when using the Radix MMU. The tlbie can
race with an mtpid (move to PID register, essentially MMU context
switch) on another thread of the core, which can cause stores to
continue to go to a page after it's unmapped.
- A fix in our KVM code to add a missing barrier, the lack of which
has been observed to cause missed IPIs and subsequently stuck CPUs
in the host.
- A change to the way we initialise PCR (Processor Compatibility
Register) to make it forward compatible with future CPUs.
- On some older PowerVM systems our H_BLOCK_REMOVE support could
oops, fix it to detect such systems and fallback to the old
invalidation method.
- A fix for an oops seen on some machines when using KASAN on 32-bit.
- A handful of other minor fixes, and two new selftests.
Thanks to: Alistair Popple, Aneesh Kumar K.V, Christophe Leroy,
Gustavo Romero, Joel Stanley, Jordan Niethe, Laurent Dufour, Michael
Roth, Oliver O'Halloran"
* tag 'powerpc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/eeh: Fix eeh eeh_debugfs_break_device() with SRIOV devices
powerpc/nvdimm: use H_SCM_QUERY hcall on H_OVERLAP error
powerpc/nvdimm: Use HCALL error as the return value
selftests/powerpc: Add test case for tlbie vs mtpidr ordering issue
powerpc/mm: Fixup tlbie vs mtpidr/mtlpidr ordering issue on POWER9
powerpc/book3s64/radix: Rename CPU_FTR_P9_TLBIE_BUG feature flag
powerpc/book3s64/mm: Don't do tlbie fixup for some hardware revisions
powerpc/pseries: Call H_BLOCK_REMOVE when supported
powerpc/pseries: Read TLB Block Invalidate Characteristics
KVM: PPC: Book3S HV: use smp_mb() when setting/clearing host_ipi flag
powerpc/mm: Fix an Oops in kasan_mmu_init()
powerpc/mm: Add a helper to select PAGE_KERNEL_RO or PAGE_READONLY
powerpc/64s: Set reserved PCR bits
powerpc: Fix definition of PCR bits to work with old binutils
powerpc/book3s64/radix: Remove WARN_ON in destroy_context()
powerpc/tm: Add tm-poison test
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
- Apply a number of membarrier related fixes and cleanups, which fixes
a use-after-free race in the membarrier code
- Introduce proper RCU protection for tasks on the runqueue - to get
rid of the subtle task_rcu_dereference() interface that was easy to
get wrong
- Misc fixes, but also an EAS speedup
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Avoid redundant EAS calculation
sched/core: Remove double update_max_interval() call on CPU startup
sched/core: Fix preempt_schedule() interrupt return comment
sched/fair: Fix -Wunused-but-set-variable warnings
sched/core: Fix migration to invalid CPU in __set_cpus_allowed_ptr()
sched/membarrier: Return -ENOMEM to userspace on memory allocation failure
sched/membarrier: Skip IPIs when mm->mm_users == 1
selftests, sched/membarrier: Add multi-threaded test
sched/membarrier: Fix p->mm->membarrier_state racy load
sched/membarrier: Call sync_core only before usermode for same mm
sched/membarrier: Remove redundant check
sched/membarrier: Fix private expedited registration check
tasks, sched/core: RCUify the assignment of rq->curr
tasks, sched/core: With a grace period after finish_task_switch(), remove unnecessary code
tasks, sched/core: Ensure tasks are available for a grace period after leaving the runqueue
tasks: Add a count of task RCU users
sched/core: Convert vcpu_is_preempted() from macro to an inline function
sched/fair: Remove unused cfs_rq_clock_task() function
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.
From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.
The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.
There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/
- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.
The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.
The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:
lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.
This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.
New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.
The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.
Stephen Rothwell noted that commit 5d556d2cb2ee ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"
* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"The major feature in this time is IMA support for measuring and
appraising appended file signatures. In addition are a couple of bug
fixes and code cleanup to use struct_size().
In addition to the PE/COFF and IMA xattr signatures, the kexec kernel
image may be signed with an appended signature, using the same
scripts/sign-file tool that is used to sign kernel modules.
Similarly, the initramfs may contain an appended signature.
This contained a lot of refactoring of the existing appended signature
verification code, so that IMA could retain the existing framework of
calculating the file hash once, storing it in the IMA measurement list
and extending the TPM, verifying the file's integrity based on a file
hash or signature (eg. xattrs), and adding an audit record containing
the file hash, all based on policy. (The IMA support for appended
signatures patch set was posted and reviewed 11 times.)
The support for appended signature paves the way for adding other
signature verification methods, such as fs-verity, based on a single
system-wide policy. The file hash used for verifying the signature and
the signature, itself, can be included in the IMA measurement list"
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: ima_api: Use struct_size() in kzalloc()
ima: use struct_size() in kzalloc()
sefltest/ima: support appended signatures (modsig)
ima: Fix use after free in ima_read_modsig()
MODSIGN: make new include file self contained
ima: fix freeing ongoing ahash_request
ima: always return negative code for error
ima: Store the measurement again when appraising a modsig
ima: Define ima-modsig template
ima: Collect modsig
ima: Implement support for module-style appended signatures
ima: Factor xattr_verify() out of ima_appraise_measurement()
ima: Add modsig appraise_type option for module-style appended signatures
integrity: Select CONFIG_KEYS instead of depending on it
PKCS#7: Introduce pkcs7_get_digest()
PKCS#7: Refactor verify_pkcs7_signature()
MODSIGN: Export module signature definitions
ima: initialize the "template" field with the default template
Merge tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Highlights:
- Add a new knfsd file cache, so that we don't have to open and close
on each (NFSv2/v3) READ or WRITE. This can speed up read and write
in some cases. It also replaces our readahead cache.
- Prevent silent data loss on write errors, by treating write errors
like server reboots for the purposes of write caching, thus forcing
clients to resend their writes.
- Tweak the code that allocates sessions to be more forgiving, so
that NFSv4.1 mounts are less likely to hang when a server already
has a lot of clients.
- Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be
limited only by the backend filesystem and the maximum RPC size.
- Allow the server to enforce use of the correct kerberos credentials
when a client reclaims state after a reboot.
And some miscellaneous smaller bugfixes and cleanup"
* tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits)
sunrpc: clean up indentation issue
nfsd: fix nfs read eof detection
nfsd: Make nfsd_reset_boot_verifier_locked static
nfsd: degraded slot-count more gracefully as allocation nears exhaustion.
nfsd: handle drc over-allocation gracefully.
nfsd: add support for upcall version 2
nfsd: add a "GetVersion" upcall for nfsdcld
nfsd: Reset the boot verifier on all write I/O errors
nfsd: Don't garbage collect files that might contain write errors
nfsd: Support the server resetting the boot verifier
nfsd: nfsd_file cache entries should be per net namespace
nfsd: eliminate an unnecessary acl size limit
Deprecate nfsd fault injection
nfsd: remove duplicated include from filecache.c
nfsd: Fix the documentation for svcxdr_tmpalloc()
nfsd: Fix up some unused variable warnings
nfsd: close cached files prior to a REMOVE or RENAME that would replace target
nfsd: rip out the raparms cache
nfsd: have nfsd_test_lock use the nfsd_file cache
nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache
...
Merge tag 'virtio-fs-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse virtio-fs support from Miklos Szeredi:
"Virtio-fs allows exporting directory trees on the host and mounting
them in guest(s).
This isn't actually a new filesystem, but a glue layer between the
fuse filesystem and a virtio based back-end.
It's similar in functionality to the existing virtio-9p solution, but
significantly faster in benchmarks and has better POSIX compliance.
Further permformance improvements can be achieved by sharing the page
cache between host and guest, allowing for faster I/O and reduced
memory use.
Kata Containers have been including the out-of-tree virtio-fs (with
the shared page cache patches as well) since version 1.7 as an
experimental feature. They have been active in development and plan to
switch from virtio-9p to virtio-fs as their default solution. There
has been interest from other sources as well.
The userspace infrastructure is slated to be merged into qemu once the
kernel part hits mainline.
This was developed by Vivek Goyal, Dave Gilbert and Stefan Hajnoczi"
* tag 'virtio-fs-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
virtio-fs: add virtiofs filesystem
virtio-fs: add Documentation/filesystems/virtiofs.rst
fuse: reserve values for mapping protocol
Merge tag '9p-for-5.4' of git://github.com/martinetd/linux
Pull 9p updates from Dominique Martinet:
"Some of the usual small fixes and cleanup.
Small fixes all around:
- avoid overlayfs copy-up for PRIVATE mmaps
- KUMSAN uninitialized warning for transport error
- one syzbot memory leak fix in 9p cache
- internal API cleanup for v9fs_fill_super"
* tag '9p-for-5.4' of git://github.com/martinetd/linux:
9p/vfs_super.c: Remove unused parameter data in v9fs_fill_super
9p/cache.c: Fix memory leak in v9fs_cache_session_get_cookie
9p: Transport error uninitialized
9p: avoid attaching writeback_fid on mmap with type PRIVATE
Merge tag 'riscv/for-v5.4-rc1-b' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull more RISC-V updates from Paul Walmsley:
"Some additional RISC-V updates.
This includes one significant fix:
- Prevent interrupts from being unconditionally re-enabled during
exception handling if they were disabled in the context in which
the exception occurred
Also a few other fixes:
- Fix a build error when sparse memory support is manually enabled
- Prevent CPUs beyond CONFIG_NR_CPUS from being enabled in early boot
And a few minor improvements:
- DT improvements: in the FU540 SoC DT files, improve U-Boot
compatibility by adding an "ethernet0" alias, drop an unnecessary
property from the DT files, and add support for the PWM device
- KVM preparation: add a KVM-related macro for future RISC-V KVM
support, and export some symbols required to build KVM support as
modules
- defconfig additions: build more drivers by default for QEMU
configurations"
* tag 'riscv/for-v5.4-rc1-b' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Avoid interrupts being erroneously enabled in handle_exception()
riscv: dts: sifive: Drop "clock-frequency" property of cpu nodes
riscv: dts: sifive: Add ethernet0 to the aliases node
RISC-V: Export kernel symbols for kvm
KVM: RISC-V: Add KVM_REG_RISCV for ONE_REG interface
arch/riscv: disable excess harts before picking main boot hart
RISC-V: Enable VIRTIO drivers in RV64 and RV32 defconfig
RISC-V: Fix building error when CONFIG_SPARSEMEM_MANUAL=y
riscv: dts: Add DT support for SiFive FU540 PWM driver
Merge tag 'pwm/for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
"Besides one new driver being added for the PWM controller found in
various Spreadtrum SoCs, this series of changes brings a slew of,
mostly minor, fixes and cleanups for existing drivers, as well as some
enhancements to the core code.
Lastly, Uwe is added to the PWM subsystem entry of the MAINTAINERS
file, making official his role as a reviewer"
* tag 'pwm/for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (34 commits)
MAINTAINERS: Add myself as reviewer for the PWM subsystem
MAINTAINERS: Add patchwork link for PWM entry
MAINTAINERS: Add a selection of PWM related keywords to the PWM entry
pwm: mediatek: Add MT7629 compatible string
dt-bindings: pwm: Update bindings for MT7629 SoC
pwm: mediatek: Update license and switch to SPDX tag
pwm: mediatek: Use pwm_mediatek as common prefix
pwm: mediatek: Allocate the clks array dynamically
pwm: mediatek: Remove the has_clks field
pwm: mediatek: Drop the check for of_device_get_match_data()
pwm: atmel: Consolidate driver data initialization
pwm: atmel: Remove unneeded check for match data
pwm: atmel: Remove platform_device_id and use only dt bindings
pwm: stm32-lp: Add check in case requested period cannot be achieved
pwm: Ensure pwm_apply_state() doesn't modify the state argument
pwm: fsl-ftm: Don't update the state for the caller of pwm_apply_state()
pwm: sun4i: Don't update the state for the caller of pwm_apply_state()
pwm: rockchip: Don't update the state for the caller of pwm_apply_state()
pwm: Let pwm_get_state() return the last implemented state
pwm: Introduce local struct pwm_chip in pwm_apply_state()
...
Merge tag 'for-5.4/io_uring-2019-09-27' of git://git.kernel.dk/linux-block
Pull more io_uring updates from Jens Axboe:
"Just two things in here:
- Improvement to the io_uring CQ ring wakeup for batched IO (me)
- Fix wrong comparison in poll handling (yangerkun)
I realize the first one is a little late in the game, but it felt
pointless to hold it off until the next release. Went through various
testing and reviews with Pavel and peterz"
* tag 'for-5.4/io_uring-2019-09-27' of git://git.kernel.dk/linux-block:
io_uring: make CQ ring wakeups be more efficient
io_uring: compare cached_cq_tail with cq.head in_io_uring_poll
Merge tag 'for-linus-2019-09-27' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A few fixes/changes to round off this merge window. This contains:
- Small series making some functional tweaks to blk-iocost (Tejun)
- Elevator switch locking fix (Ming)
- Kill redundant call in blk-wbt (Yufen)
- Fix flush timeout handling (Yufen)"
* tag 'for-linus-2019-09-27' of git://git.kernel.dk/linux-block:
block: fix null pointer dereference in blk_mq_rq_timed_out()
rq-qos: get rid of redundant wbt_update_limits()
iocost: bump up default latency targets for hard disks
iocost: improve nr_lagging handling
iocost: better trace vrate changes
block: don't release queue's sysfs lock during switching elevator
blk-mq: move lockdep_assert_held() into elevator_exit
nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
In nfp_abm_u32_knode_replace if the allocation for match fails it should
go to the error handling instead of returning. Updated other gotos to
have correct errno returned, too.
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Thu, 26 Sep 2019 22:42:51 +0000 (15:42 -0700)]
tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
Yuchung Cheng and Marek Majkowski independently reported a weird
behavior of TCP_USER_TIMEOUT option when used at connect() time.
When the TCP_USER_TIMEOUT is reached, tcp_write_timeout()
believes the flow should live, and the following condition
in tcp_clamp_rto_to_user_timeout() programs one jiffie timers :
remaining = icsk->icsk_user_timeout - elapsed;
if (remaining <= 0)
return 1; /* user timeout has passed; fire ASAP */
This silly situation ends when the max syn rtx count is reached.
This patch makes sure we honor both TCP_SYNCNT and TCP_USER_TIMEOUT,
avoiding these spurious SYN packets.
Fixes: dfdd79d8341c ("tcp: Add tcp_clamp_rto_to_user_timeout() helper to improve accuracy") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Yuchung Cheng <ycheng@google.com> Reported-by: Marek Majkowski <marek@cloudflare.com> Cc: Jon Maxwell <jmaxwell37@gmail.com> Link: https://marc.info/?l=linux-netdev&m=156940118307949&w=2 Acked-by: Jon Maxwell <jmaxwell37@gmail.com> Tested-by: Marek Majkowski <marek@cloudflare.com> Signed-off-by: Marek Majkowski <marek@cloudflare.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
sk_buff: drop all skb extensions on free and skb scrubbing
Now that we have a 3rd extension, add a new helper that drops the
extension space and use it when we need to scrub an sk_buff.
At this time, scrubbing clears secpath and bridge netfilter data, but
retains the tc skb extension, after this patch all three get cleared.
NAPI reuse/free assumes we can only have a secpath attached to skb, but
it seems better to clear all extensions there as well.
v2: add unlikely hint (Eric Dumazet)
Fixes: f821382a5512 ("net: openvswitch: Set OvS recirc_id from tc chain index") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
There was a bug in the previous logic that attempted to ensure gain cycling
gets inflight above BDP even for small BDPs. This code correctly raised and
lowered target inflight values during the gain cycle. And this code
correctly ensured that cwnd was raised when probing bandwidth. However, it
did not correspondingly ensure that cwnd was *not* raised in this way when
*not* probing for bandwidth. The result was that small-BDP flows that were
always cwnd-bound could go for many cycles with a fixed cwnd, and not probe
or yield bandwidth at all. This meant that multiple small-BDP flows could
fail to converge in their bandwidth allocations.
Fixes: 3c346b233c68 ("tcp_bbr: fix bw probing to raise in-flight data for very small BDPs") Signed-off-by: Kevin(Yudong) Yang <yyd@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Priyaranjan Jha <priyarjha@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 27 Sep 2019 18:33:19 +0000 (20:33 +0200)]
Merge branch 'mlxsw-Various-fixes'
Ido Schimmel says:
====================
mlxsw: Various fixes
This patchset includes two small fixes for the mlxsw driver and one
patch which clarifies recently introduced devlink-trap documentation.
Patch #1 clears the port's VLAN filters during port initialization. This
ensures that the drop reason reported to the user is consistent. The
problem is explained in detail in the commit message.
Patch #2 clarifies the description of one of the traps exposed via
devlink-trap.
Patch #3 from Danielle forbids the installation of a tc filter with
multiple mirror actions since this is not supported by the device. The
failure is communicated to the user via extack.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
mlxsw: spectrum: Clear VLAN filters during port initialization
When a port is created, its VLAN filters are not cleared by the
firmware. This causes tagged packets to be later dropped by the ingress
STP filters, which default to DISCARD state.
The above did not matter much until commit f313c87b4f4e ("mlxsw:
spectrum: Add devlink-trap support") where we exposed the drop reason to
users.
Without this patch, the drop reason users will see is not consistent. If
a port is enslaved to a VLAN-aware bridge and a packet with an invalid
VLAN tries to ingress the bridge, it will be dropped due to ingress STP
filter. If the VLAN is later enabled and then disabled, the packet will
be dropped by the ingress VLAN filter despite the above being a
seemingly NOP operation.
Fix this by clearing all the VLAN filters during port initialization.
Adjust the test accordingly.
Fixes: f313c87b4f4e ("mlxsw: spectrum: Add devlink-trap support") Reported-by: Alex Kushnarov <alexanderk@mellanox.com> Tested-by: Alex Kushnarov <alexanderk@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
projects / kernel.git / log