<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/Makefile, branch v4.16</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Linux 4.16</title>
<updated>2018-04-01T21:20:27+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-04-01T21:20:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0adb32858b0bddf4ada5f364a84ed60b196dbcda'/>
<id>0adb32858b0bddf4ada5f364a84ed60b196dbcda</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-fixes-v4.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2018-03-31T04:53:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-31T04:53:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b5dbc28762fd3fd40ba76303be0c7f707826f982'/>
<id>b5dbc28762fd3fd40ba76303be0c7f707826f982</id>
<content type='text'>
Pull Kbuild fixes from Masahiro Yamada:

 - fix missed rebuild of TRIM_UNUSED_KSYMS

 - fix rpm-pkg for GNU tar &gt;= 1.29

 - include scripts/dtc/include-prefixes/* to kernel header deb-pkg

 - add -no-integrated-as option ealier to fix building with Clang

 - fix netfilter Makefile for parallel building

* tag 'kbuild-fixes-v4.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  netfilter: nf_nat_snmp_basic: add correct dependency to Makefile
  kbuild: rpm-pkg: Support GNU tar &gt;= 1.29
  builddeb: Fix header package regarding dtc source links
  kbuild: set no-integrated-as before incl. arch Makefile
  kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Kbuild fixes from Masahiro Yamada:

 - fix missed rebuild of TRIM_UNUSED_KSYMS

 - fix rpm-pkg for GNU tar &gt;= 1.29

 - include scripts/dtc/include-prefixes/* to kernel header deb-pkg

 - add -no-integrated-as option ealier to fix building with Clang

 - fix netfilter Makefile for parallel building

* tag 'kbuild-fixes-v4.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  netfilter: nf_nat_snmp_basic: add correct dependency to Makefile
  kbuild: rpm-pkg: Support GNU tar &gt;= 1.29
  builddeb: Fix header package regarding dtc source links
  kbuild: set no-integrated-as before incl. arch Makefile
  kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
</pre>
</div>
</content>
</entry>
<entry>
<title>Linux 4.16-rc7</title>
<updated>2018-03-25T22:44:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-25T22:44:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3eb2ce825ea1ad89d20f7a3b5780df850e4be274'/>
<id>3eb2ce825ea1ad89d20f7a3b5780df850e4be274</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2018-03-22T21:10:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-22T21:10:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c4f4d2f917729e9b7b8bb452bf4971be93e7a15f'/>
<id>c4f4d2f917729e9b7b8bb452bf4971be93e7a15f</id>
<content type='text'>
Pull networking fixes from David Miller:

 1) Always validate XFRM esn replay attribute, from Florian Westphal.

 2) Fix RCU read lock imbalance in xfrm_get_tos(), from Xin Long.

 3) Don't try to get firmware dump if not loaded in iwlwifi, from Shaul
    Triebitz.

 4) Fix BPF helpers to deal with SCTP GSO SKBs properly, from Daniel
    Axtens.

 5) Fix some interrupt handling issues in e1000e driver, from Benjamin
    Poitier.

 6) Use strlcpy() in several ethtool get_strings methods, from Florian
    Fainelli.

 7) Fix rhlist dup insertion, from Paul Blakey.

 8) Fix SKB leak in netem packet scheduler, from Alexey Kodanev.

 9) Fix driver unload crash when link is up in smsc911x, from Jeremy
    Linton.

10) Purge out invalid socket types in l2tp_tunnel_create(), from Eric
    Dumazet.

11) Need to purge the write queue when TCP connections are aborted,
    otherwise userspace using MSG_ZEROCOPY can't close the fd. From
    Soheil Hassas Yeganeh.

12) Fix double free in error path of team driver, from Arkadi
    Sharshevsky.

13) Filter fixes for hv_netvsc driver, from Stephen Hemminger.

14) Fix non-linear packet access in ipv6 ndisc code, from Lorenzo
    Bianconi.

15) Properly filter out unsupported feature flags in macvlan driver,
    from Shannon Nelson.

16) Don't request loading the diag module for a protocol if the protocol
    itself is not even registered. From Xin Long.

17) If datagram connect fails in ipv6, make sure the socket state is
    consistent afterwards. From Paolo Abeni.

18) Use after free in qed driver, from Dan Carpenter.

19) If received ipv4 PMTU is less than the min pmtu, lock the mtu in the
    entry. From Sabrina Dubroca.

20) Fix sleep in atomic in tg3 driver, from Jonathan Toppins.

21) Fix vlan in vlan untagging in some situations, from Toshiaki Makita.

22) Fix double SKB free in genlmsg_mcast(). From Nicolas Dichtel.

23) Fix NULL derefs in error paths of tcf_*_init(), from Davide Caratti.

24) Unbalanced PM runtime calls in FEC driver, from Florian Fainelli.

25) Memory leak in gemini driver, from Igor Pylypiv.

26) IDR leaks in error paths of tcf_*_init() functions, from Davide
    Caratti.

27) Need to use GFP_ATOMIC in seg6_build_state(), from David Lebrun.

28) Missing dev_put() in error path of macsec_newlink(), from Dan
    Carpenter.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (201 commits)
  macsec: missing dev_put() on error in macsec_newlink()
  net: dsa: Fix functional dsa-loop dependency on FIXED_PHY
  hv_netvsc: common detach logic
  hv_netvsc: change GPAD teardown order on older versions
  hv_netvsc: use RCU to fix concurrent rx and queue changes
  hv_netvsc: disable NAPI before channel close
  net/ipv6: Handle onlink flag with multipath routes
  ppp: avoid loop in xmit recursion detection code
  ipv6: sr: fix NULL pointer dereference when setting encap source address
  ipv6: sr: fix scheduling in RCU when creating seg6 lwtunnel state
  net: aquantia: driver version bump
  net: aquantia: Implement pci shutdown callback
  net: aquantia: Allow live mac address changes
  net: aquantia: Add tx clean budget and valid budget handling logic
  net: aquantia: Change inefficient wait loop on fw data reads
  net: aquantia: Fix a regression with reset on old firmware
  net: aquantia: Fix hardware reset when SPI may rarely hangup
  s390/qeth: on channel error, reject further cmd requests
  s390/qeth: lock read device while queueing next buffer
  s390/qeth: when thread completes, wake up all waiters
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from David Miller:

 1) Always validate XFRM esn replay attribute, from Florian Westphal.

 2) Fix RCU read lock imbalance in xfrm_get_tos(), from Xin Long.

 3) Don't try to get firmware dump if not loaded in iwlwifi, from Shaul
    Triebitz.

 4) Fix BPF helpers to deal with SCTP GSO SKBs properly, from Daniel
    Axtens.

 5) Fix some interrupt handling issues in e1000e driver, from Benjamin
    Poitier.

 6) Use strlcpy() in several ethtool get_strings methods, from Florian
    Fainelli.

 7) Fix rhlist dup insertion, from Paul Blakey.

 8) Fix SKB leak in netem packet scheduler, from Alexey Kodanev.

 9) Fix driver unload crash when link is up in smsc911x, from Jeremy
    Linton.

10) Purge out invalid socket types in l2tp_tunnel_create(), from Eric
    Dumazet.

11) Need to purge the write queue when TCP connections are aborted,
    otherwise userspace using MSG_ZEROCOPY can't close the fd. From
    Soheil Hassas Yeganeh.

12) Fix double free in error path of team driver, from Arkadi
    Sharshevsky.

13) Filter fixes for hv_netvsc driver, from Stephen Hemminger.

14) Fix non-linear packet access in ipv6 ndisc code, from Lorenzo
    Bianconi.

15) Properly filter out unsupported feature flags in macvlan driver,
    from Shannon Nelson.

16) Don't request loading the diag module for a protocol if the protocol
    itself is not even registered. From Xin Long.

17) If datagram connect fails in ipv6, make sure the socket state is
    consistent afterwards. From Paolo Abeni.

18) Use after free in qed driver, from Dan Carpenter.

19) If received ipv4 PMTU is less than the min pmtu, lock the mtu in the
    entry. From Sabrina Dubroca.

20) Fix sleep in atomic in tg3 driver, from Jonathan Toppins.

21) Fix vlan in vlan untagging in some situations, from Toshiaki Makita.

22) Fix double SKB free in genlmsg_mcast(). From Nicolas Dichtel.

23) Fix NULL derefs in error paths of tcf_*_init(), from Davide Caratti.

24) Unbalanced PM runtime calls in FEC driver, from Florian Fainelli.

25) Memory leak in gemini driver, from Igor Pylypiv.

26) IDR leaks in error paths of tcf_*_init() functions, from Davide
    Caratti.

27) Need to use GFP_ATOMIC in seg6_build_state(), from David Lebrun.

28) Missing dev_put() in error path of macsec_newlink(), from Dan
    Carpenter.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (201 commits)
  macsec: missing dev_put() on error in macsec_newlink()
  net: dsa: Fix functional dsa-loop dependency on FIXED_PHY
  hv_netvsc: common detach logic
  hv_netvsc: change GPAD teardown order on older versions
  hv_netvsc: use RCU to fix concurrent rx and queue changes
  hv_netvsc: disable NAPI before channel close
  net/ipv6: Handle onlink flag with multipath routes
  ppp: avoid loop in xmit recursion detection code
  ipv6: sr: fix NULL pointer dereference when setting encap source address
  ipv6: sr: fix scheduling in RCU when creating seg6 lwtunnel state
  net: aquantia: driver version bump
  net: aquantia: Implement pci shutdown callback
  net: aquantia: Allow live mac address changes
  net: aquantia: Add tx clean budget and valid budget handling logic
  net: aquantia: Change inefficient wait loop on fw data reads
  net: aquantia: Fix a regression with reset on old firmware
  net: aquantia: Fix hardware reset when SPI may rarely hangup
  s390/qeth: on channel error, reject further cmd requests
  s390/qeth: lock read device while queueing next buffer
  s390/qeth: when thread completes, wake up all waiters
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: set no-integrated-as before incl. arch Makefile</title>
<updated>2018-03-21T09:20:11+00:00</updated>
<author>
<name>Stefan Agner</name>
<email>stefan@agner.ch</email>
</author>
<published>2018-03-19T21:12:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0f0e8de334c54c38818a4a5390a39aa09deff5bf'/>
<id>0f0e8de334c54c38818a4a5390a39aa09deff5bf</id>
<content type='text'>
In order to make sure compiler flag detection for ARM works
correctly the no-integrated-as flags need to be set before
including the arch specific Makefile.

Fixes: cfe17c9bbe6a ("kbuild: move cc-option and cc-disable-warning after incl. arch Makefile")
Signed-off-by: Stefan Agner &lt;stefan@agner.ch&gt;
Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In order to make sure compiler flag detection for ARM works
correctly the no-integrated-as flags need to be set before
including the arch specific Makefile.

Fixes: cfe17c9bbe6a ("kbuild: move cc-option and cc-disable-warning after incl. arch Makefile")
Signed-off-by: Stefan Agner &lt;stefan@agner.ch&gt;
Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: disable clang's default use of -fmerge-all-constants</title>
<updated>2018-03-21T00:43:15+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2018-03-21T00:18:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=87e0d4f0f37fb0c8c4aeeac46fff5e957738df79'/>
<id>87e0d4f0f37fb0c8c4aeeac46fff5e957738df79</id>
<content type='text'>
Prasad reported that he has seen crashes in BPF subsystem with netd
on Android with arm64 in the form of (note, the taint is unrelated):

  [ 4134.721483] Unable to handle kernel paging request at virtual address 800000001
  [ 4134.820925] Mem abort info:
  [ 4134.901283]   Exception class = DABT (current EL), IL = 32 bits
  [ 4135.016736]   SET = 0, FnV = 0
  [ 4135.119820]   EA = 0, S1PTW = 0
  [ 4135.201431] Data abort info:
  [ 4135.301388]   ISV = 0, ISS = 0x00000021
  [ 4135.359599]   CM = 0, WnR = 0
  [ 4135.470873] user pgtable: 4k pages, 39-bit VAs, pgd = ffffffe39b946000
  [ 4135.499757] [0000000800000001] *pgd=0000000000000000, *pud=0000000000000000
  [ 4135.660725] Internal error: Oops: 96000021 [#1] PREEMPT SMP
  [ 4135.674610] Modules linked in:
  [ 4135.682883] CPU: 5 PID: 1260 Comm: netd Tainted: G S      W       4.14.19+ #1
  [ 4135.716188] task: ffffffe39f4aa380 task.stack: ffffff801d4e0000
  [ 4135.731599] PC is at bpf_prog_add+0x20/0x68
  [ 4135.741746] LR is at bpf_prog_inc+0x20/0x2c
  [ 4135.751788] pc : [&lt;ffffff94ab7ad584&gt;] lr : [&lt;ffffff94ab7ad638&gt;] pstate: 60400145
  [ 4135.769062] sp : ffffff801d4e3ce0
  [...]
  [ 4136.258315] Process netd (pid: 1260, stack limit = 0xffffff801d4e0000)
  [ 4136.273746] Call trace:
  [...]
  [ 4136.442494] 3ca0: ffffff94ab7ad584 0000000060400145 ffffffe3a01bf8f8 0000000000000006
  [ 4136.460936] 3cc0: 0000008000000000 ffffff94ab844204 ffffff801d4e3cf0 ffffff94ab7ad584
  [ 4136.479241] [&lt;ffffff94ab7ad584&gt;] bpf_prog_add+0x20/0x68
  [ 4136.491767] [&lt;ffffff94ab7ad638&gt;] bpf_prog_inc+0x20/0x2c
  [ 4136.504536] [&lt;ffffff94ab7b5d08&gt;] bpf_obj_get_user+0x204/0x22c
  [ 4136.518746] [&lt;ffffff94ab7ade68&gt;] SyS_bpf+0x5a8/0x1a88

Android's netd was basically pinning the uid cookie BPF map in BPF
fs (/sys/fs/bpf/traffic_cookie_uid_map) and later on retrieving it
again resulting in above panic. Issue is that the map was wrongly
identified as a prog! Above kernel was compiled with clang 4.0,
and it turns out that clang decided to merge the bpf_prog_iops and
bpf_map_iops into a single memory location, such that the two i_ops
could then not be distinguished anymore.

Reason for this miscompilation is that clang has the more aggressive
-fmerge-all-constants enabled by default. In fact, clang source code
has a comment about it in lib/AST/ExprConstant.cpp on why it is okay
to do so:

  Pointers with different bases cannot represent the same object.
  (Note that clang defaults to -fmerge-all-constants, which can
  lead to inconsistent results for comparisons involving the address
  of a constant; this generally doesn't matter in practice.)

The issue never appeared with gcc however, since gcc does not enable
-fmerge-all-constants by default and even *explicitly* states in
it's option description that using this flag results in non-conforming
behavior, quote from man gcc:

  Languages like C or C++ require each variable, including multiple
  instances of the same variable in recursive calls, to have distinct
  locations, so using this option results in non-conforming behavior.

There are also various clang bug reports open on that matter [1],
where clang developers acknowledge the non-conforming behavior,
and refer to disabling it with -fno-merge-all-constants. But even
if this gets fixed in clang today, there are already users out there
that triggered this. Thus, fix this issue by explicitly adding
-fno-merge-all-constants to the kernel's Makefile to generically
disable this optimization, since potentially other places in the
kernel could subtly break as well.

Note, there is also a flag called -fmerge-constants (not supported
by clang), which is more conservative and only applies to strings
and it's enabled in gcc's -O/-O2/-O3/-Os optimization levels. In
gcc's code, the two flags -fmerge-{all-,}constants share the same
variable internally, so when disabling it via -fno-merge-all-constants,
then we really don't merge any const data (e.g. strings), and text
size increases with gcc (14,927,214 -&gt; 14,942,646 for vmlinux.o).

  $ gcc -fverbose-asm -O2 foo.c -S -o foo.S
    -&gt; foo.S lists -fmerge-constants under options enabled
  $ gcc -fverbose-asm -O2 -fno-merge-all-constants foo.c -S -o foo.S
    -&gt; foo.S doesn't list -fmerge-constants under options enabled
  $ gcc -fverbose-asm -O2 -fno-merge-all-constants -fmerge-constants foo.c -S -o foo.S
    -&gt; foo.S lists -fmerge-constants under options enabled

Thus, as a workaround we need to set both -fno-merge-all-constants
*and* -fmerge-constants in the Makefile in order for text size to
stay as is.

  [1] https://bugs.llvm.org/show_bug.cgi?id=18538

Reported-by: Prasad Sodagudi &lt;psodagud@codeaurora.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Chenbo Feng &lt;fengc@google.com&gt;
Cc: Richard Smith &lt;richard-llvm@metafoo.co.uk&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: linux-kernel@vger.kernel.org
Tested-by: Prasad Sodagudi &lt;psodagud@codeaurora.org&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Prasad reported that he has seen crashes in BPF subsystem with netd
on Android with arm64 in the form of (note, the taint is unrelated):

  [ 4134.721483] Unable to handle kernel paging request at virtual address 800000001
  [ 4134.820925] Mem abort info:
  [ 4134.901283]   Exception class = DABT (current EL), IL = 32 bits
  [ 4135.016736]   SET = 0, FnV = 0
  [ 4135.119820]   EA = 0, S1PTW = 0
  [ 4135.201431] Data abort info:
  [ 4135.301388]   ISV = 0, ISS = 0x00000021
  [ 4135.359599]   CM = 0, WnR = 0
  [ 4135.470873] user pgtable: 4k pages, 39-bit VAs, pgd = ffffffe39b946000
  [ 4135.499757] [0000000800000001] *pgd=0000000000000000, *pud=0000000000000000
  [ 4135.660725] Internal error: Oops: 96000021 [#1] PREEMPT SMP
  [ 4135.674610] Modules linked in:
  [ 4135.682883] CPU: 5 PID: 1260 Comm: netd Tainted: G S      W       4.14.19+ #1
  [ 4135.716188] task: ffffffe39f4aa380 task.stack: ffffff801d4e0000
  [ 4135.731599] PC is at bpf_prog_add+0x20/0x68
  [ 4135.741746] LR is at bpf_prog_inc+0x20/0x2c
  [ 4135.751788] pc : [&lt;ffffff94ab7ad584&gt;] lr : [&lt;ffffff94ab7ad638&gt;] pstate: 60400145
  [ 4135.769062] sp : ffffff801d4e3ce0
  [...]
  [ 4136.258315] Process netd (pid: 1260, stack limit = 0xffffff801d4e0000)
  [ 4136.273746] Call trace:
  [...]
  [ 4136.442494] 3ca0: ffffff94ab7ad584 0000000060400145 ffffffe3a01bf8f8 0000000000000006
  [ 4136.460936] 3cc0: 0000008000000000 ffffff94ab844204 ffffff801d4e3cf0 ffffff94ab7ad584
  [ 4136.479241] [&lt;ffffff94ab7ad584&gt;] bpf_prog_add+0x20/0x68
  [ 4136.491767] [&lt;ffffff94ab7ad638&gt;] bpf_prog_inc+0x20/0x2c
  [ 4136.504536] [&lt;ffffff94ab7b5d08&gt;] bpf_obj_get_user+0x204/0x22c
  [ 4136.518746] [&lt;ffffff94ab7ade68&gt;] SyS_bpf+0x5a8/0x1a88

Android's netd was basically pinning the uid cookie BPF map in BPF
fs (/sys/fs/bpf/traffic_cookie_uid_map) and later on retrieving it
again resulting in above panic. Issue is that the map was wrongly
identified as a prog! Above kernel was compiled with clang 4.0,
and it turns out that clang decided to merge the bpf_prog_iops and
bpf_map_iops into a single memory location, such that the two i_ops
could then not be distinguished anymore.

Reason for this miscompilation is that clang has the more aggressive
-fmerge-all-constants enabled by default. In fact, clang source code
has a comment about it in lib/AST/ExprConstant.cpp on why it is okay
to do so:

  Pointers with different bases cannot represent the same object.
  (Note that clang defaults to -fmerge-all-constants, which can
  lead to inconsistent results for comparisons involving the address
  of a constant; this generally doesn't matter in practice.)

The issue never appeared with gcc however, since gcc does not enable
-fmerge-all-constants by default and even *explicitly* states in
it's option description that using this flag results in non-conforming
behavior, quote from man gcc:

  Languages like C or C++ require each variable, including multiple
  instances of the same variable in recursive calls, to have distinct
  locations, so using this option results in non-conforming behavior.

There are also various clang bug reports open on that matter [1],
where clang developers acknowledge the non-conforming behavior,
and refer to disabling it with -fno-merge-all-constants. But even
if this gets fixed in clang today, there are already users out there
that triggered this. Thus, fix this issue by explicitly adding
-fno-merge-all-constants to the kernel's Makefile to generically
disable this optimization, since potentially other places in the
kernel could subtly break as well.

Note, there is also a flag called -fmerge-constants (not supported
by clang), which is more conservative and only applies to strings
and it's enabled in gcc's -O/-O2/-O3/-Os optimization levels. In
gcc's code, the two flags -fmerge-{all-,}constants share the same
variable internally, so when disabling it via -fno-merge-all-constants,
then we really don't merge any const data (e.g. strings), and text
size increases with gcc (14,927,214 -&gt; 14,942,646 for vmlinux.o).

  $ gcc -fverbose-asm -O2 foo.c -S -o foo.S
    -&gt; foo.S lists -fmerge-constants under options enabled
  $ gcc -fverbose-asm -O2 -fno-merge-all-constants foo.c -S -o foo.S
    -&gt; foo.S doesn't list -fmerge-constants under options enabled
  $ gcc -fverbose-asm -O2 -fno-merge-all-constants -fmerge-constants foo.c -S -o foo.S
    -&gt; foo.S lists -fmerge-constants under options enabled

Thus, as a workaround we need to set both -fno-merge-all-constants
*and* -fmerge-constants in the Makefile in order for text size to
stay as is.

  [1] https://bugs.llvm.org/show_bug.cgi?id=18538

Reported-by: Prasad Sodagudi &lt;psodagud@codeaurora.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Chenbo Feng &lt;fengc@google.com&gt;
Cc: Richard Smith &lt;richard-llvm@metafoo.co.uk&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: linux-kernel@vger.kernel.org
Tested-by: Prasad Sodagudi &lt;psodagud@codeaurora.org&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Linux 4.16-rc6</title>
<updated>2018-03-19T00:48:42+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-19T00:48:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c698ca5278934c0ae32297a8725ced2e27585d7f'/>
<id>c698ca5278934c0ae32297a8725ced2e27585d7f</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Linux 4.16-rc5</title>
<updated>2018-03-12T00:25:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-12T00:25:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0c8efd610b58cb23cefdfa12015799079aef94ae'/>
<id>0c8efd610b58cb23cefdfa12015799079aef94ae</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Linux 4.16-rc4</title>
<updated>2018-03-04T22:54:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-04T22:54:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=661e50bc853209e41a5c14a290ca4decc43cbfd1'/>
<id>661e50bc853209e41a5c14a290ca4decc43cbfd1</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'kbuild-fixes-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild</title>
<updated>2018-03-03T18:37:01+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-03T18:37:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0eb3412a68c354c0aa4adc4a24ec533154bd2172'/>
<id>0eb3412a68c354c0aa4adc4a24ec533154bd2172</id>
<content type='text'>
Pull Kbuild fixes from Masahiro Yamada:

 - suppress sparse warnings about unknown attributes

 - fix typos and stale comments

 - fix build error of arch/sh

 - fix wrong use of ld-option vs cc-ldoption

 - remove redundant GCC_PLUGINS_CFLAGS assignment

 - fix another memory leak of Kconfig

 - fix line number in error messages of Kconfig

 - do not write confusing CONFIG_DEFCONFIG_LIST out to .config

 - add xstrdup() to Kconfig to handle memory shortage errors

 - show also a Debian package name if ncurses is missing

* tag 'kbuild-fixes-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  MAINTAINERS: take over Kconfig maintainership
  kconfig: fix line number in recursive inclusion error message
  Coccinelle: memdup: Fix typo in warning messages
  kconfig: Update ncurses package names for menuconfig
  kbuild/kallsyms: trivial typo fix
  kbuild: test --build-id linker flag by ld-option instead of cc-ldoption
  kbuild: drop superfluous GCC_PLUGINS_CFLAGS assignment
  kconfig: Don't leak choice names during parsing
  sh: fix build error for empty CONFIG_BUILTIN_DTB_SOURCE
  kconfig: set SYMBOL_AUTO to the symbol marked with defconfig_list
  kconfig: add xstrdup() helper
  kbuild: disable sparse warnings about unknown attributes
  Makefile: Fix lying comment re. silentoldconfig
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull Kbuild fixes from Masahiro Yamada:

 - suppress sparse warnings about unknown attributes

 - fix typos and stale comments

 - fix build error of arch/sh

 - fix wrong use of ld-option vs cc-ldoption

 - remove redundant GCC_PLUGINS_CFLAGS assignment

 - fix another memory leak of Kconfig

 - fix line number in error messages of Kconfig

 - do not write confusing CONFIG_DEFCONFIG_LIST out to .config

 - add xstrdup() to Kconfig to handle memory shortage errors

 - show also a Debian package name if ncurses is missing

* tag 'kbuild-fixes-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  MAINTAINERS: take over Kconfig maintainership
  kconfig: fix line number in recursive inclusion error message
  Coccinelle: memdup: Fix typo in warning messages
  kconfig: Update ncurses package names for menuconfig
  kbuild/kallsyms: trivial typo fix
  kbuild: test --build-id linker flag by ld-option instead of cc-ldoption
  kbuild: drop superfluous GCC_PLUGINS_CFLAGS assignment
  kconfig: Don't leak choice names during parsing
  sh: fix build error for empty CONFIG_BUILTIN_DTB_SOURCE
  kconfig: set SYMBOL_AUTO to the symbol marked with defconfig_list
  kconfig: add xstrdup() helper
  kbuild: disable sparse warnings about unknown attributes
  Makefile: Fix lying comment re. silentoldconfig
</pre>
</div>
</content>
</entry>
</feed>
