<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/tools/include/uapi/linux, branch v5.15</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>tools headers UAPI: Sync linux/fs.h with the kernel sources</title>
<updated>2021-09-11T19:14:53+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-05-21T19:00:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2bae3e64ec465cd545c5cbec74335eb44f97c177'/>
<id>2bae3e64ec465cd545c5cbec74335eb44f97c177</id>
<content type='text'>
To pick the change in:

  7957d93bf32bc211 ("block: add ioctl to read the disk sequence number")

It adds a new ioctl, but we are still not using that to generate tables
for 'perf trace', so no changes in tooling.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
  diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h

Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Matteo Croce &lt;mcroce@microsoft.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick the change in:

  7957d93bf32bc211 ("block: add ioctl to read the disk sequence number")

It adds a new ioctl, but we are still not using that to generate tables
for 'perf trace', so no changes in tooling.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
  diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h

Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Matteo Croce &lt;mcroce@microsoft.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers UAPI: Sync linux/in.h copy with the kernel sources</title>
<updated>2021-09-11T19:12:26+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-06-19T13:15:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ee286c60c268aed03bac4686ebb47f1534b4b2e2'/>
<id>ee286c60c268aed03bac4686ebb47f1534b4b2e2</id>
<content type='text'>
To pick the changes in:

  db243b796439c0ca ("net/ipv4/ipv6: Replace one-element arraya with flexible-array members")
  2d3e5caf96b9449a ("net/ipv4: Replace one-element array with flexible-array member")

That don't result in any change in tooling, the structs changed remains
with the same layout.

This addresses this build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/in.h' differs from latest version at 'include/uapi/linux/in.h'
  diff -u tools/include/uapi/linux/in.h include/uapi/linux/in.h

Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick the changes in:

  db243b796439c0ca ("net/ipv4/ipv6: Replace one-element arraya with flexible-array members")
  2d3e5caf96b9449a ("net/ipv4: Replace one-element array with flexible-array member")

That don't result in any change in tooling, the structs changed remains
with the same layout.

This addresses this build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/in.h' differs from latest version at 'include/uapi/linux/in.h'
  diff -u tools/include/uapi/linux/in.h include/uapi/linux/in.h

Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools include UAPI: Update linux/mount.h copy</title>
<updated>2021-09-10T21:15:22+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-07-01T16:34:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=37ce9e4fc596cf10a4d32ced741679bd1b4fa7a5'/>
<id>37ce9e4fc596cf10a4d32ced741679bd1b4fa7a5</id>
<content type='text'>
To pick the changes from:

  9ffb14ef61bab83f ("move_mount: allow to add a mount into an existing group")

That ends up adding support for the new MOVE_MOUNT_SET_GROUP move_mount
flag.

  $ tools/perf/trace/beauty/move_mount_flags.sh &gt; before
  $ cp include/uapi/linux/mount.h tools/include/uapi/linux/mount.h
  $ tools/perf/trace/beauty/move_mount_flags.sh &gt; after
  $ diff -u before after
  --- before	2021-09-10 12:28:43.865279808 -0300
  +++ after	2021-09-10 12:28:50.183429184 -0300
  @@ -5,4 +5,5 @@
   	[ilog2(0x00000010) + 1] = "T_SYMLINKS",
   	[ilog2(0x00000020) + 1] = "T_AUTOMOUNTS",
   	[ilog2(0x00000040) + 1] = "T_EMPTY_PATH",
  +	[ilog2(0x00000100) + 1] = "SET_GROUP",
   };
  $

So now one can use it in --filter expressions for tracepoints.

This silences this perf build warnings:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/mount.h' differs from latest version at 'include/uapi/linux/mount.h'
  diff -u tools/include/uapi/linux/mount.h include/uapi/linux/mount.h

Cc: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Cc: Pavel Tikhomirov &lt;ptikhomirov@virtuozzo.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick the changes from:

  9ffb14ef61bab83f ("move_mount: allow to add a mount into an existing group")

That ends up adding support for the new MOVE_MOUNT_SET_GROUP move_mount
flag.

  $ tools/perf/trace/beauty/move_mount_flags.sh &gt; before
  $ cp include/uapi/linux/mount.h tools/include/uapi/linux/mount.h
  $ tools/perf/trace/beauty/move_mount_flags.sh &gt; after
  $ diff -u before after
  --- before	2021-09-10 12:28:43.865279808 -0300
  +++ after	2021-09-10 12:28:50.183429184 -0300
  @@ -5,4 +5,5 @@
   	[ilog2(0x00000010) + 1] = "T_SYMLINKS",
   	[ilog2(0x00000020) + 1] = "T_AUTOMOUNTS",
   	[ilog2(0x00000040) + 1] = "T_EMPTY_PATH",
  +	[ilog2(0x00000100) + 1] = "SET_GROUP",
   };
  $

So now one can use it in --filter expressions for tracepoints.

This silences this perf build warnings:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/mount.h' differs from latest version at 'include/uapi/linux/mount.h'
  diff -u tools/include/uapi/linux/mount.h include/uapi/linux/mount.h

Cc: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Cc: Pavel Tikhomirov &lt;ptikhomirov@virtuozzo.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers UAPI: Sync linux/prctl.h with the kernel sources</title>
<updated>2021-09-10T21:15:22+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-02-11T15:50:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c3ef25c4a60cc18cf3f05a74c78220748f25684'/>
<id>2c3ef25c4a60cc18cf3f05a74c78220748f25684</id>
<content type='text'>
To pick the changes in:

  433c38f40f6a81cf ("arm64: mte: change ASYNC and SYNC TCF settings into bitfields")
  e893bb1bb4d2eb63 ("x86, prctl: Hook L1D flushing in via prctl")

That don't result in any changes in tooling:

  $ tools/perf/trace/beauty/prctl_option.sh &gt; before
  $ cp include/uapi/linux/prctl.h tools/include/uapi/linux/prctl.h
  $ tools/perf/trace/beauty/prctl_option.sh &gt; after
  $ diff -u before after
  $

Just silences this perf tools build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/prctl.h' differs from latest version at 'include/uapi/linux/prctl.h'
  diff -u tools/include/uapi/linux/prctl.h include/uapi/linux/prctl.h

Cc: Balbir Singh &lt;sblbir@amazon.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Peter Collingbourne &lt;pcc@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick the changes in:

  433c38f40f6a81cf ("arm64: mte: change ASYNC and SYNC TCF settings into bitfields")
  e893bb1bb4d2eb63 ("x86, prctl: Hook L1D flushing in via prctl")

That don't result in any changes in tooling:

  $ tools/perf/trace/beauty/prctl_option.sh &gt; before
  $ cp include/uapi/linux/prctl.h tools/include/uapi/linux/prctl.h
  $ tools/perf/trace/beauty/prctl_option.sh &gt; after
  $ diff -u before after
  $

Just silences this perf tools build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/prctl.h' differs from latest version at 'include/uapi/linux/prctl.h'
  diff -u tools/include/uapi/linux/prctl.h include/uapi/linux/prctl.h

Cc: Balbir Singh &lt;sblbir@amazon.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Peter Collingbourne &lt;pcc@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers UAPI: Sync linux/kvm.h with the kernel sources</title>
<updated>2021-09-10T21:15:22+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-05-09T12:39:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dfa00459c6264abd282452c4878e3a9117db23bb'/>
<id>dfa00459c6264abd282452c4878e3a9117db23bb</id>
<content type='text'>
To pick the changes in:

  f95937ccf5bd5e0a ("KVM: stats: Support linear and logarithmic histogram statistics")
  f0376edb1ddcab19 ("KVM: arm64: Add ioctl to fetch/store tags in a guest")
  ea7fc1bb1cd1b92b ("KVM: arm64: Introduce MTE VM feature")

That just rebuilds perf, as these patches don't add any new KVM ioctl to
be harvested for the the 'perf trace' ioctl syscall argument
beautifiers.

This is also by now used by tools/testing/selftests/kvm/, so that will
pick the new KVM_STATS_TYPE_LINEAR_HIST and KVM_STATS_TYPE_LOG_HIST
defines.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
  diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h

Cc: Jing Zhang &lt;jingzhangos@google.com&gt;
Cc: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Steven Price &lt;steven.price@arm.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick the changes in:

  f95937ccf5bd5e0a ("KVM: stats: Support linear and logarithmic histogram statistics")
  f0376edb1ddcab19 ("KVM: arm64: Add ioctl to fetch/store tags in a guest")
  ea7fc1bb1cd1b92b ("KVM: arm64: Introduce MTE VM feature")

That just rebuilds perf, as these patches don't add any new KVM ioctl to
be harvested for the the 'perf trace' ioctl syscall argument
beautifiers.

This is also by now used by tools/testing/selftests/kvm/, so that will
pick the new KVM_STATS_TYPE_LINEAR_HIST and KVM_STATS_TYPE_LOG_HIST
defines.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
  diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h

Cc: Jing Zhang &lt;jingzhangos@google.com&gt;
Cc: Marc Zyngier &lt;maz@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Steven Price &lt;steven.price@arm.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next</title>
<updated>2021-08-30T23:42:47+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2021-08-30T23:42:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=19a31d79219cdd66484721f564ee68293dcc6c24'/>
<id>19a31d79219cdd66484721f564ee68293dcc6c24</id>
<content type='text'>
Daniel Borkmann says:

====================
bpf-next 2021-08-31

We've added 116 non-merge commits during the last 17 day(s) which contain
a total of 126 files changed, 6813 insertions(+), 4027 deletions(-).

The main changes are:

1) Add opaque bpf_cookie to perf link which the program can read out again,
   to be used in libbpf-based USDT library, from Andrii Nakryiko.

2) Add bpf_task_pt_regs() helper to access userspace pt_regs, from Daniel Xu.

3) Add support for UNIX stream type sockets for BPF sockmap, from Jiang Wang.

4) Allow BPF TCP congestion control progs to call bpf_setsockopt() e.g. to switch
   to another congestion control algorithm during init, from Martin KaFai Lau.

5) Extend BPF iterator support for UNIX domain sockets, from Kuniyuki Iwashima.

6) Allow bpf_{set,get}sockopt() calls from setsockopt progs, from Prankur Gupta.

7) Add bpf_get_netns_cookie() helper for BPF_PROG_TYPE_{SOCK_OPS,CGROUP_SOCKOPT}
   progs, from Xu Liu and Stanislav Fomichev.

8) Support for __weak typed ksyms in libbpf, from Hao Luo.

9) Shrink struct cgroup_bpf by 504 bytes through refactoring, from Dave Marchevsky.

10) Fix a smatch complaint in verifier's narrow load handling, from Andrey Ignatov.

11) Fix BPF interpreter's tail call count limit, from Daniel Borkmann.

12) Big batch of improvements to BPF selftests, from Magnus Karlsson, Li Zhijian,
    Yucong Sun, Yonghong Song, Ilya Leoshkevich, Jussi Maki, Ilya Leoshkevich, others.

13) Another big batch to revamp XDP samples in order to give them consistent look
    and feel, from Kumar Kartikeya Dwivedi.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (116 commits)
  MAINTAINERS: Remove self from powerpc BPF JIT
  selftests/bpf: Fix potential unreleased lock
  samples: bpf: Fix uninitialized variable in xdp_redirect_cpu
  selftests/bpf: Reduce more flakyness in sockmap_listen
  bpf: Fix bpf-next builds without CONFIG_BPF_EVENTS
  bpf: selftests: Add dctcp fallback test
  bpf: selftests: Add connect_to_fd_opts to network_helpers
  bpf: selftests: Add sk_state to bpf_tcp_helpers.h
  bpf: tcp: Allow bpf-tcp-cc to call bpf_(get|set)sockopt
  selftests: xsk: Preface options with opt
  selftests: xsk: Make enums lower case
  selftests: xsk: Generate packets from specification
  selftests: xsk: Generate packet directly in umem
  selftests: xsk: Simplify cleanup of ifobjects
  selftests: xsk: Decrease sending speed
  selftests: xsk: Validate tx stats on tx thread
  selftests: xsk: Simplify packet validation in xsk tests
  selftests: xsk: Rename worker_* functions that are not thread entry points
  selftests: xsk: Disassociate umem size with packets sent
  selftests: xsk: Remove end-of-test packet
  ...
====================

Link: https://lore.kernel.org/r/20210830225618.11634-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Daniel Borkmann says:

====================
bpf-next 2021-08-31

We've added 116 non-merge commits during the last 17 day(s) which contain
a total of 126 files changed, 6813 insertions(+), 4027 deletions(-).

The main changes are:

1) Add opaque bpf_cookie to perf link which the program can read out again,
   to be used in libbpf-based USDT library, from Andrii Nakryiko.

2) Add bpf_task_pt_regs() helper to access userspace pt_regs, from Daniel Xu.

3) Add support for UNIX stream type sockets for BPF sockmap, from Jiang Wang.

4) Allow BPF TCP congestion control progs to call bpf_setsockopt() e.g. to switch
   to another congestion control algorithm during init, from Martin KaFai Lau.

5) Extend BPF iterator support for UNIX domain sockets, from Kuniyuki Iwashima.

6) Allow bpf_{set,get}sockopt() calls from setsockopt progs, from Prankur Gupta.

7) Add bpf_get_netns_cookie() helper for BPF_PROG_TYPE_{SOCK_OPS,CGROUP_SOCKOPT}
   progs, from Xu Liu and Stanislav Fomichev.

8) Support for __weak typed ksyms in libbpf, from Hao Luo.

9) Shrink struct cgroup_bpf by 504 bytes through refactoring, from Dave Marchevsky.

10) Fix a smatch complaint in verifier's narrow load handling, from Andrey Ignatov.

11) Fix BPF interpreter's tail call count limit, from Daniel Borkmann.

12) Big batch of improvements to BPF selftests, from Magnus Karlsson, Li Zhijian,
    Yucong Sun, Yonghong Song, Ilya Leoshkevich, Jussi Maki, Ilya Leoshkevich, others.

13) Another big batch to revamp XDP samples in order to give them consistent look
    and feel, from Kumar Kartikeya Dwivedi.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (116 commits)
  MAINTAINERS: Remove self from powerpc BPF JIT
  selftests/bpf: Fix potential unreleased lock
  samples: bpf: Fix uninitialized variable in xdp_redirect_cpu
  selftests/bpf: Reduce more flakyness in sockmap_listen
  bpf: Fix bpf-next builds without CONFIG_BPF_EVENTS
  bpf: selftests: Add dctcp fallback test
  bpf: selftests: Add connect_to_fd_opts to network_helpers
  bpf: selftests: Add sk_state to bpf_tcp_helpers.h
  bpf: tcp: Allow bpf-tcp-cc to call bpf_(get|set)sockopt
  selftests: xsk: Preface options with opt
  selftests: xsk: Make enums lower case
  selftests: xsk: Generate packets from specification
  selftests: xsk: Generate packet directly in umem
  selftests: xsk: Simplify cleanup of ifobjects
  selftests: xsk: Decrease sending speed
  selftests: xsk: Validate tx stats on tx thread
  selftests: xsk: Simplify packet validation in xsk tests
  selftests: xsk: Rename worker_* functions that are not thread entry points
  selftests: xsk: Disassociate umem size with packets sent
  selftests: xsk: Remove end-of-test packet
  ...
====================

Link: https://lore.kernel.org/r/20210830225618.11634-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: add IFLA_INET6_RA_MTU to expose mtu value</title>
<updated>2021-08-28T00:29:18+00:00</updated>
<author>
<name>Rocco Yue</name>
<email>rocco.yue@mediatek.com</email>
</author>
<published>2021-08-27T15:04:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7'/>
<id>49b99da2c9ce13ffcd93fe3a0f5670791c1d76f7</id>
<content type='text'>
The kernel provides a "/proc/sys/net/ipv6/conf/&lt;iface&gt;/mtu"
file, which can temporarily record the mtu value of the last
received RA message when the RA mtu value is lower than the
interface mtu, but this proc has following limitations:

(1) when the interface mtu (/sys/class/net/&lt;iface&gt;/mtu) is
updeated, mtu6 (/proc/sys/net/ipv6/conf/&lt;iface&gt;/mtu) will
be updated to the value of interface mtu;
(2) mtu6 (/proc/sys/net/ipv6/conf/&lt;iface&gt;/mtu) only affect
ipv6 connection, and not affect ipv4.

Therefore, when the mtu option is carried in the RA message,
there will be a problem that the user sometimes cannot obtain
RA mtu value correctly by reading mtu6.

After this patch set, if a RA message carries the mtu option,
you can send a netlink msg which nlmsg_type is RTM_GETLINK,
and then by parsing the attribute of IFLA_INET6_RA_MTU to
get the mtu value carried in the RA message received on the
inet6 device. In addition, you can also get a link notification
when ra_mtu is updated so it doesn't have to poll.

In this way, if the MTU values that the device receives from
the network in the PCO IPv4 and the RA IPv6 procedures are
different, the user can obtain the correct ipv6 ra_mtu value
and compare the value of ra_mtu and ipv4 mtu, then the device
can use the lower MTU value for both IPv4 and IPv6.

Signed-off-by: Rocco Yue &lt;rocco.yue@mediatek.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20210827150412.9267-1-rocco.yue@mediatek.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The kernel provides a "/proc/sys/net/ipv6/conf/&lt;iface&gt;/mtu"
file, which can temporarily record the mtu value of the last
received RA message when the RA mtu value is lower than the
interface mtu, but this proc has following limitations:

(1) when the interface mtu (/sys/class/net/&lt;iface&gt;/mtu) is
updeated, mtu6 (/proc/sys/net/ipv6/conf/&lt;iface&gt;/mtu) will
be updated to the value of interface mtu;
(2) mtu6 (/proc/sys/net/ipv6/conf/&lt;iface&gt;/mtu) only affect
ipv6 connection, and not affect ipv4.

Therefore, when the mtu option is carried in the RA message,
there will be a problem that the user sometimes cannot obtain
RA mtu value correctly by reading mtu6.

After this patch set, if a RA message carries the mtu option,
you can send a netlink msg which nlmsg_type is RTM_GETLINK,
and then by parsing the attribute of IFLA_INET6_RA_MTU to
get the mtu value carried in the RA message received on the
inet6 device. In addition, you can also get a link notification
when ra_mtu is updated so it doesn't have to poll.

In this way, if the MTU values that the device receives from
the network in the PCO IPv4 and the RA IPv6 procedures are
different, the user can obtain the correct ipv6 ra_mtu value
and compare the value of ra_mtu and ipv4 mtu, then the device
can use the lower MTU value for both IPv4 and IPv6.

Signed-off-by: Rocco Yue &lt;rocco.yue@mediatek.com&gt;
Reviewed-by: David Ahern &lt;dsahern@kernel.org&gt;
Link: https://lore.kernel.org/r/20210827150412.9267-1-rocco.yue@mediatek.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: Add bpf_task_pt_regs() helper</title>
<updated>2021-08-25T17:37:05+00:00</updated>
<author>
<name>Daniel Xu</name>
<email>dxu@dxuuu.xyz</email>
</author>
<published>2021-08-24T02:43:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dd6e10fbd9fb86a571d925602c8a24bb4d09a2a7'/>
<id>dd6e10fbd9fb86a571d925602c8a24bb4d09a2a7</id>
<content type='text'>
The motivation behind this helper is to access userspace pt_regs in a
kprobe handler.

uprobe's ctx is the userspace pt_regs. kprobe's ctx is the kernelspace
pt_regs. bpf_task_pt_regs() allows accessing userspace pt_regs in a
kprobe handler. The final case (kernelspace pt_regs in uprobe) is
pretty rare (usermode helper) so I think that can be solved later if
necessary.

More concretely, this helper is useful in doing BPF-based DWARF stack
unwinding. Currently the kernel can only do framepointer based stack
unwinds for userspace code. This is because the DWARF state machines are
too fragile to be computed in kernelspace [0]. The idea behind
DWARF-based stack unwinds w/ BPF is to copy a chunk of the userspace
stack (while in prog context) and send it up to userspace for unwinding
(probably with libunwind) [1]. This would effectively enable profiling
applications with -fomit-frame-pointer using kprobes and uprobes.

[0]: https://lkml.org/lkml/2012/2/10/356
[1]: https://github.com/danobi/bpf-dwarf-walk

Signed-off-by: Daniel Xu &lt;dxu@dxuuu.xyz&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/e2718ced2d51ef4268590ab8562962438ab82815.1629772842.git.dxu@dxuuu.xyz
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The motivation behind this helper is to access userspace pt_regs in a
kprobe handler.

uprobe's ctx is the userspace pt_regs. kprobe's ctx is the kernelspace
pt_regs. bpf_task_pt_regs() allows accessing userspace pt_regs in a
kprobe handler. The final case (kernelspace pt_regs in uprobe) is
pretty rare (usermode helper) so I think that can be solved later if
necessary.

More concretely, this helper is useful in doing BPF-based DWARF stack
unwinding. Currently the kernel can only do framepointer based stack
unwinds for userspace code. This is because the DWARF state machines are
too fragile to be computed in kernelspace [0]. The idea behind
DWARF-based stack unwinds w/ BPF is to copy a chunk of the userspace
stack (while in prog context) and send it up to userspace for unwinding
(probably with libunwind) [1]. This would effectively enable profiling
applications with -fomit-frame-pointer using kprobes and uprobes.

[0]: https://lkml.org/lkml/2012/2/10/356
[1]: https://github.com/danobi/bpf-dwarf-walk

Signed-off-by: Daniel Xu &lt;dxu@dxuuu.xyz&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/e2718ced2d51ef4268590ab8562962438ab82815.1629772842.git.dxu@dxuuu.xyz
</pre>
</div>
</content>
</entry>
<entry>
<title>tools: include: Add ethtool_drvinfo definition to UAPI header</title>
<updated>2021-08-24T21:48:40+00:00</updated>
<author>
<name>Kumar Kartikeya Dwivedi</name>
<email>memxor@gmail.com</email>
</author>
<published>2021-08-21T00:19:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f2e85d4a751663514c1e84ea65f334ce1ca13a28'/>
<id>f2e85d4a751663514c1e84ea65f334ce1ca13a28</id>
<content type='text'>
Instead of copying the whole header in, just add the struct definitions
we need for now. In the future it can be synced as a copy of in-tree
header if required.

Signed-off-by: Kumar Kartikeya Dwivedi &lt;memxor@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20210821002010.845777-3-memxor@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of copying the whole header in, just add the struct definitions
we need for now. In the future it can be synced as a copy of in-tree
header if required.

Signed-off-by: Kumar Kartikeya Dwivedi &lt;memxor@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20210821002010.845777-3-memxor@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: Migrate cgroup_bpf to internal cgroup_bpf_attach_type enum</title>
<updated>2021-08-24T00:50:24+00:00</updated>
<author>
<name>Dave Marchevsky</name>
<email>davemarchevsky@fb.com</email>
</author>
<published>2021-08-19T09:24:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6fc88c354f3af83ffa2c285b86e76c759755693f'/>
<id>6fc88c354f3af83ffa2c285b86e76c759755693f</id>
<content type='text'>
Add an enum (cgroup_bpf_attach_type) containing only valid cgroup_bpf
attach types and a function to map bpf_attach_type values to the new
enum. Inspired by netns_bpf_attach_type.

Then, migrate cgroup_bpf to use cgroup_bpf_attach_type wherever
possible.  Functionality is unchanged as attach_type_to_prog_type
switches in bpf/syscall.c were preventing non-cgroup programs from
making use of the invalid cgroup_bpf array slots.

As a result struct cgroup_bpf uses 504 fewer bytes relative to when its
arrays were sized using MAX_BPF_ATTACH_TYPE.

bpf_cgroup_storage is notably not migrated as struct
bpf_cgroup_storage_key is part of uapi and contains a bpf_attach_type
member which is not meant to be opaque. Similarly, bpf_cgroup_link
continues to report its bpf_attach_type member to userspace via fdinfo
and bpf_link_info.

To ease disambiguation, bpf_attach_type variables are renamed from
'type' to 'atype' when changed to cgroup_bpf_attach_type.

Signed-off-by: Dave Marchevsky &lt;davemarchevsky@fb.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20210819092420.1984861-2-davemarchevsky@fb.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add an enum (cgroup_bpf_attach_type) containing only valid cgroup_bpf
attach types and a function to map bpf_attach_type values to the new
enum. Inspired by netns_bpf_attach_type.

Then, migrate cgroup_bpf to use cgroup_bpf_attach_type wherever
possible.  Functionality is unchanged as attach_type_to_prog_type
switches in bpf/syscall.c were preventing non-cgroup programs from
making use of the invalid cgroup_bpf array slots.

As a result struct cgroup_bpf uses 504 fewer bytes relative to when its
arrays were sized using MAX_BPF_ATTACH_TYPE.

bpf_cgroup_storage is notably not migrated as struct
bpf_cgroup_storage_key is part of uapi and contains a bpf_attach_type
member which is not meant to be opaque. Similarly, bpf_cgroup_link
continues to report its bpf_attach_type member to userspace via fdinfo
and bpf_link_info.

To ease disambiguation, bpf_attach_type variables are renamed from
'type' to 'atype' when changed to cgroup_bpf_attach_type.

Signed-off-by: Dave Marchevsky &lt;davemarchevsky@fb.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20210819092420.1984861-2-davemarchevsky@fb.com
</pre>
</div>
</content>
</entry>
</feed>
