<feed xmlns='http://www.w3.org/2005/Atom'>
<title>pm24.git/kernel/bpf/Makefile, branch v4.19-rc4</title>
<subtitle>Unnamed repository; edit this file 'description' to name the repository.
</subtitle>
<id>https://git.kobert.dev/pm24.git/atom?h=v4.19-rc4</id>
<link rel='self' href='https://git.kobert.dev/pm24.git/atom?h=v4.19-rc4'/>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/'/>
<updated>2018-08-10T23:58:46Z</updated>
<entry>
<title>bpf: Introduce BPF_MAP_TYPE_REUSEPORT_SOCKARRAY</title>
<updated>2018-08-10T23:58:46Z</updated>
<author>
<name>Martin KaFai Lau</name>
<email>kafai@fb.com</email>
</author>
<published>2018-08-08T08:01:24Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=5dc4c4b7d4e8115e7cde96a030f98cb3ab2e458c'/>
<id>urn:sha1:5dc4c4b7d4e8115e7cde96a030f98cb3ab2e458c</id>
<content type='text'>
This patch introduces a new map type BPF_MAP_TYPE_REUSEPORT_SOCKARRAY.

To unleash the full potential of a bpf prog, it is essential for the
userspace to be capable of directly setting up a bpf map which can then
be consumed by the bpf prog to make decision.  In this case, decide which
SO_REUSEPORT sk to serve the incoming request.

By adding BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, the userspace has total control
and visibility on where a SO_REUSEPORT sk should be located in a bpf map.
The later patch will introduce BPF_PROG_TYPE_SK_REUSEPORT such that
the bpf prog can directly select a sk from the bpf map.  That will
raise the programmability of the bpf prog attached to a reuseport
group (a group of sk serving the same IP:PORT).

For example, in UDP, the bpf prog can peek into the payload (e.g.
through the "data" pointer introduced in the later patch) to learn
the application level's connection information and then decide which sk
to pick from a bpf map.  The userspace can tightly couple the sk's location
in a bpf map with the application logic in generating the UDP payload's
connection information.  This connection info contact/API stays within the
userspace.

Also, when used with map-in-map, the userspace can switch the
old-server-process's inner map to a new-server-process's inner map
in one call "bpf_map_update_elem(outer_map, &amp;index, &amp;new_reuseport_array)".
The bpf prog will then direct incoming requests to the new process instead
of the old process.  The old process can finish draining the pending
requests (e.g. by "accept()") before closing the old-fds.  [Note that
deleting a fd from a bpf map does not necessary mean the fd is closed]

During map_update_elem(),
Only SO_REUSEPORT sk (i.e. which has already been added
to a reuse-&gt;socks[]) can be used.  That means a SO_REUSEPORT sk that is
"bind()" for UDP or "bind()+listen()" for TCP.  These conditions are
ensured in "reuseport_array_update_check()".

A SO_REUSEPORT sk can only be added once to a map (i.e. the
same sk cannot be added twice even to the same map).  SO_REUSEPORT
already allows another sk to be created for the same IP:PORT.
There is no need to re-create a similar usage in the BPF side.

When a SO_REUSEPORT is deleted from the "reuse-&gt;socks[]" (e.g. "close()"),
it will notify the bpf map to remove it from the map also.  It is
done through "bpf_sk_reuseport_detach()" and it will only be called
if &gt;=1 of the "reuse-&gt;sock[]" has ever been added to a bpf map.

The map_update()/map_delete() has to be in-sync with the
"reuse-&gt;socks[]".  Hence, the same "reuseport_lock" used
by "reuse-&gt;socks[]" has to be used here also. Care has
been taken to ensure the lock is only acquired when the
adding sk passes some strict tests. and
freeing the map does not require the reuseport_lock.

The reuseport_array will also support lookup from the syscall
side.  It will return a sock_gen_cookie().  The sock_gen_cookie()
is on-demand (i.e. a sk's cookie is not generated until the very
first map_lookup_elem()).

The lookup cookie is 64bits but it goes against the logical userspace
expectation on 32bits sizeof(fd) (and as other fd based bpf maps do also).
It may catch user in surprise if we enforce value_size=8 while
userspace still pass a 32bits fd during update.  Supporting different
value_size between lookup and update seems unintuitive also.

We also need to consider what if other existing fd based maps want
to return 64bits value from syscall's lookup in the future.
Hence, reuseport_array supports both value_size 4 and 8, and
assuming user will usually use value_size=4.  The syscall's lookup
will return ENOSPC on value_size=4.  It will will only
return 64bits value from sock_gen_cookie() when user consciously
choose value_size=8 (as a signal that lookup is desired) which then
requires a 64bits value in both lookup and update.

Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
</entry>
<entry>
<title>bpf: introduce cgroup storage maps</title>
<updated>2018-08-02T22:47:32Z</updated>
<author>
<name>Roman Gushchin</name>
<email>guro@fb.com</email>
</author>
<published>2018-08-02T21:27:18Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=de9cbbaadba5adf88a19e46df61f7054000838f6'/>
<id>urn:sha1:de9cbbaadba5adf88a19e46df61f7054000838f6</id>
<content type='text'>
This commit introduces BPF_MAP_TYPE_CGROUP_STORAGE maps:
a special type of maps which are implementing the cgroup storage.

&gt;From the userspace point of view it's almost a generic
hash map with the (cgroup inode id, attachment type) pair
used as a key.

The only difference is that some operations are restricted:
  1) a user can't create new entries,
  2) a user can't remove existing entries.

The lookup from userspace is o(log(n)).

Signed-off-by: Roman Gushchin &lt;guro@fb.com&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
</entry>
<entry>
<title>bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP</title>
<updated>2018-05-03T22:55:24Z</updated>
<author>
<name>Björn Töpel</name>
<email>bjorn.topel@intel.com</email>
</author>
<published>2018-05-02T11:01:28Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=fbfc504a24f53f7ebe128ab55cb5dba634f4ece8'/>
<id>urn:sha1:fbfc504a24f53f7ebe128ab55cb5dba634f4ece8</id>
<content type='text'>
The xskmap is yet another BPF map, very much inspired by
dev/cpu/sockmap, and is a holder of AF_XDP sockets. A user application
adds AF_XDP sockets into the map, and by using the bpf_redirect_map
helper, an XDP program can redirect XDP frames to an AF_XDP socket.

Note that a socket that is bound to certain ifindex/queue index will
*only* accept XDP frames from that netdev/queue index. If an XDP
program tries to redirect from a netdev/queue index other than what
the socket is bound to, the frame will not be received on the socket.

A socket can reside in multiple maps.

v3: Fixed race and simplified code.
v2: Removed one indirection in map lookup.

Signed-off-by: Björn Töpel &lt;bjorn.topel@intel.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
</entry>
<entry>
<title>bpf: btf: Introduce BPF Type Format (BTF)</title>
<updated>2018-04-19T19:46:24Z</updated>
<author>
<name>Martin KaFai Lau</name>
<email>kafai@fb.com</email>
</author>
<published>2018-04-18T22:55:57Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=69b693f0aefa0ed521e8bd02260523b5ae446ad7'/>
<id>urn:sha1:69b693f0aefa0ed521e8bd02260523b5ae446ad7</id>
<content type='text'>
This patch introduces BPF type Format (BTF).

BTF (BPF Type Format) is the meta data format which describes
the data types of BPF program/map.  Hence, it basically focus
on the C programming language which the modern BPF is primary
using.  The first use case is to provide a generic pretty print
capability for a BPF map.

BTF has its root from CTF (Compact C-Type format).  To simplify
the handling of BTF data, BTF removes the differences between
small and big type/struct-member.  Hence, BTF consistently uses u32
instead of supporting both "one u16" and "two u32 (+padding)" in
describing type and struct-member.

It also raises the number of types (and functions) limit
from 0x7fff to 0x7fffffff.

Due to the above changes,  the format is not compatible to CTF.
Hence, BTF starts with a new BTF_MAGIC and version number.

This patch does the first verification pass to the BTF.  The first
pass checks:
1. meta-data size (e.g. It does not go beyond the total btf's size)
2. name_offset is valid
3. Each BTF_KIND (e.g. int, enum, struct....) does its
   own check of its meta-data.

Some other checks, like checking a struct's member is referring
to a valid type, can only be done in the second pass.  The second
verification pass will be implemented in the next patch.

Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Alexei Starovoitov &lt;ast@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
</entry>
<entry>
<title>bpf: only build sockmap with CONFIG_INET</title>
<updated>2018-01-04T18:01:14Z</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2018-01-04T01:57:56Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=5f103c5d4dbadec0f2cacd39b6429e1b8a8cf983'/>
<id>urn:sha1:5f103c5d4dbadec0f2cacd39b6429e1b8a8cf983</id>
<content type='text'>
The sockmap infrastructure is only aware of TCP sockets at the
moment. In the future we plan to add UDP. In both cases CONFIG_NET
should be built-in.

So lets only build sockmap if CONFIG_INET is enabled.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
</entry>
<entry>
<title>bpf: offload: add infrastructure for loading programs for a specific netdev</title>
<updated>2017-11-05T13:26:18Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>jakub.kicinski@netronome.com</email>
</author>
<published>2017-11-03T20:56:17Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=ab3f0063c48c26c927851b6767824e35a716d878'/>
<id>urn:sha1:ab3f0063c48c26c927851b6767824e35a716d878</id>
<content type='text'>
The fact that we don't know which device the program is going
to be used on is quite limiting in current eBPF infrastructure.
We have to reverse or limit the changes which kernel makes to
the loaded bytecode if we want it to be offloaded to a networking
device.  We also have to invent new APIs for debugging and
troubleshooting support.

Make it possible to load programs for a specific netdev.  This
helps us to bring the debug information closer to the core
eBPF infrastructure (e.g. we will be able to reuse the verifer
log in device JIT).  It allows device JITs to perform translation
on the original bytecode.

__bpf_prog_get() when called to get a reference for an attachment
point will now refuse to give it if program has a device assigned.
Following patches will add a version of that function which passes
the expected netdev in. @type argument in __bpf_prog_get() is
renamed to attach_type to make it clearer that it's only set on
attachment.

All calls to ndo_bpf are protected by rtnl, only verifier callbacks
are not.  We need a wait queue to make sure netdev doesn't get
destroyed while verifier is still running and calling its driver.

Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Reviewed-by: Quentin Monnet &lt;quentin.monnet@netronome.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2017-11-04T00:26:51Z</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2017-11-04T00:26:51Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=2a171788ba7bb61995e98e8163204fc7880f63b2'/>
<id>urn:sha1:2a171788ba7bb61995e98e8163204fc7880f63b2</id>
<content type='text'>
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>License cleanup: add SPDX GPL-2.0 license identifier to files with no license</title>
<updated>2017-11-02T10:10:55Z</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2017-11-01T14:07:57Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=b24413180f5600bcb3bb70fbed5cf186b60864bd'/>
<id>urn:sha1:b24413180f5600bcb3bb70fbed5cf186b60864bd</id>
<content type='text'>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode &amp; Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained &gt;5
   lines of source
 - File already had some variant of a license header in it (even if &lt;5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart &lt;kstewart@linuxfoundation.org&gt;
Reviewed-by: Philippe Ombredanne &lt;pombredanne@nexb.com&gt;
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP</title>
<updated>2017-10-18T11:12:18Z</updated>
<author>
<name>Jesper Dangaard Brouer</name>
<email>brouer@redhat.com</email>
</author>
<published>2017-10-16T10:19:28Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=6710e1126934d8b4372b4d2f9ae1646cd3f151bf'/>
<id>urn:sha1:6710e1126934d8b4372b4d2f9ae1646cd3f151bf</id>
<content type='text'>
The 'cpumap' is primarily used as a backend map for XDP BPF helper
call bpf_redirect_map() and XDP_REDIRECT action, like 'devmap'.

This patch implement the main part of the map.  It is not connected to
the XDP redirect system yet, and no SKB allocation are done yet.

The main concern in this patch is to ensure the datapath can run
without any locking.  This adds complexity to the setup and tear-down
procedure, which assumptions are extra carefully documented in the
code comments.

V2:
 - make sure array isn't larger than NR_CPUS
 - make sure CPUs added is a valid possible CPU

V3: fix nitpicks from Jakub Kicinski &lt;kubakici@wp.pl&gt;

V5:
 - Restrict map allocation to root / CAP_SYS_ADMIN
 - WARN_ON_ONCE if queue is not empty on tear-down
 - Return -EPERM on memlock limit instead of -ENOMEM
 - Error code in __cpu_map_entry_alloc() also handle ptr_ring_cleanup()
 - Moved cpu_map_enqueue() to next patch

V6: all notice by Daniel Borkmann
 - Fix err return code in cpu_map_alloc() introduced in V5
 - Move cpu_possible() check after max_entries boundary check
 - Forbid usage initially in check_map_func_compatibility()

V7:
 - Fix alloc error path spotted by Daniel Borkmann
 - Did stress test adding+removing CPUs from the map concurrently
 - Fixed refcnt issue on cpu_map_entry, kthread started too soon
 - Make sure packets are flushed during tear-down, involved use of
   rcu_barrier() and kthread_run only exit after queue is empty
 - Fix alloc error path in __cpu_map_entry_alloc() for ptr_ring

V8:
 - Nitpicking comments and gramma by Edward Cree
 - Fix missing semi-colon introduced in V7 due to rebasing
 - Move struct bpf_cpu_map_entry members cpu+map_id to tracepoint patch

Signed-off-by: Jesper Dangaard Brouer &lt;brouer@redhat.com&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>bpf: move instruction printing into a separate file</title>
<updated>2017-10-10T19:30:16Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>jakub.kicinski@netronome.com</email>
</author>
<published>2017-10-09T17:30:12Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=f4ac7e0b5cc8d16004ac57ff679266d573f30f77'/>
<id>urn:sha1:f4ac7e0b5cc8d16004ac57ff679266d573f30f77</id>
<content type='text'>
Separate the instruction printing into a standalone source file.
This way sneaky code from tools/ can compile it in directly.

Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
