Commit Graph

1611 Commits

Author SHA1 Message Date
Linus Torvalds
cd6c84d8f0 Linux 5.2-rc2 2019-05-26 16:49:19 -07:00
Linus Torvalds
a188339ca5 Linux 5.2-rc1 2019-05-19 15:47:09 -07:00
Masahiro Yamada
3a48a91901 kbuild: check uniqueness of module names
In the recent build test of linux-next, Stephen saw a build error
caused by a broken .tmp_versions/*.mod file:

  https://lkml.org/lkml/2019/5/13/991

drivers/net/phy/asix.ko and drivers/net/usb/asix.ko have the same
basename, and there is a race in generating .tmp_versions/asix.mod

Kbuild has not checked this before, and it suddenly shows up with
obscure error messages when this kind of race occurs.

Non-unique module names cause various sort of problems, but it is
not trivial to catch them by eyes.

Hence, this script.

It checks not only real modules, but also built-in modules (i.e.
controlled by tristate CONFIG option, but currently compiled with =y).
Non-unique names for built-in modules also cause problems because
/sys/modules/ would fall over.

For the latest kernel, I tested "make allmodconfig all" (or more
quickly "make allyesconfig modules"), and it detected the following:

warning: same basename if the following are built as modules:
  drivers/regulator/88pm800.ko
  drivers/mfd/88pm800.ko
warning: same basename if the following are built as modules:
  drivers/gpu/drm/bridge/adv7511/adv7511.ko
  drivers/media/i2c/adv7511.ko
warning: same basename if the following are built as modules:
  drivers/net/phy/asix.ko
  drivers/net/usb/asix.ko
warning: same basename if the following are built as modules:
  fs/coda/coda.ko
  drivers/media/platform/coda/coda.ko
warning: same basename if the following are built as modules:
  drivers/net/phy/realtek.ko
  drivers/net/dsa/realtek.ko

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
2019-05-18 15:35:02 +09:00
Masahiro Yamada
233c741dcb kbuild: add LICENSES to KBUILD_ALLDIRS
For *-pkg targets, the LICENSES directory should be included in the
source tarball.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:57 +09:00
Masahiro Yamada
902a6898bf kbuild: terminate Kconfig when $(CC) or $(LD) is missing
If the compiler specified by $(CC) is not present, the Kconfig stage
sprinkles 'not found' messages, then succeeds.

  $ make CROSS_COMPILE=foo defconfig
  /bin/sh: 1: foogcc: not found
  /bin/sh: 1: foogcc: not found
  *** Default configuration is based on 'x86_64_defconfig'
  ./scripts/gcc-version.sh: 17: ./scripts/gcc-version.sh: foogcc: not found
  ./scripts/gcc-version.sh: 18: ./scripts/gcc-version.sh: foogcc: not found
  ./scripts/gcc-version.sh: 19: ./scripts/gcc-version.sh: foogcc: not found
  ./scripts/gcc-version.sh: 17: ./scripts/gcc-version.sh: foogcc: not found
  ./scripts/gcc-version.sh: 18: ./scripts/gcc-version.sh: foogcc: not found
  ./scripts/gcc-version.sh: 19: ./scripts/gcc-version.sh: foogcc: not found
  ./scripts/clang-version.sh: 11: ./scripts/clang-version.sh: foogcc: not found
  ./scripts/gcc-plugin.sh: 11: ./scripts/gcc-plugin.sh: foogcc: not found
  init/Kconfig:16:warning: 'GCC_VERSION': number is invalid
  #
  # configuration written to .config
  #

Terminate parsing files immediately if $(CC) or $(LD) is not found.
"make *config" will fail more nicely.

  $ make CROSS_COMPILE=foo defconfig
  *** Default configuration is based on 'x86_64_defconfig'
  scripts/Kconfig.include:34: compiler 'foogcc' not found
  make[1]: *** [scripts/kconfig/Makefile;82: defconfig] Error 1
  make: *** [Makefile;557: defconfig] Error 2

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:55 +09:00
Masahiro Yamada
d2f8ae0e4c kbuild: turn auto.conf.cmd into a mandatory include file
syncconfig is responsible for keeping auto.conf up-to-date, so if it
fails for any reason, the build must be terminated immediately.

However, since commit 9390dff66a ("kbuild: invoke syncconfig if
include/config/auto.conf.cmd is missing"), Kbuild continues running
even after syncconfig fails.

You can confirm this by intentionally making syncconfig error out:

  diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
  index 08ba146..307b9de 100644
  --- a/scripts/kconfig/confdata.c
  +++ b/scripts/kconfig/confdata.c
  @@ -1023,6 +1023,9 @@ int conf_write_autoconf(int overwrite)
          FILE *out, *tristate, *out_h;
          int i;

  +       if (overwrite)
  +               return 1;
  +
          if (!overwrite && is_present(autoconf_name))
                  return 0;

Then, syncconfig fails, but Make would not stop:

  $ make -s mrproper allyesconfig defconfig
  $ make
  scripts/kconfig/conf  --syncconfig Kconfig

  *** Error during sync of the configuration.

  make[2]: *** [scripts/kconfig/Makefile;69: syncconfig] Error 1
  make[1]: *** [Makefile;557: syncconfig] Error 2
  make: *** [include/config/auto.conf.cmd] Deleting file 'include/config/tristate.conf'
  make: Failed to remake makefile 'include/config/auto.conf'.
    SYSTBL  arch/x86/include/generated/asm/syscalls_32.h
    SYSHDR  arch/x86/include/generated/asm/unistd_32_ia32.h
    SYSHDR  arch/x86/include/generated/asm/unistd_64_x32.h
    SYSTBL  arch/x86/include/generated/asm/syscalls_64.h
  [ continue running ... ]

The reason is in the behavior of a pattern rule with multi-targets.

  %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
          $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig

GNU Make knows this rule is responsible for making all the three files
simultaneously. As far as examined, auto.conf.cmd is the target in
question when this rule is invoked. It is probably because auto.conf.cmd
is included below the inclusion of auto.conf.

The inclusion of auto.conf is mandatory, while that of auto.conf.cmd
is optional. GNU Make does not care about the failure in the process
of updating optional include files.

I filed this issue (https://savannah.gnu.org/bugs/?56301) in case this
behavior could be improved somehow in future releases of GNU Make.
Anyway, it is quite easy to fix our Makefile.

Given that auto.conf is already a mandatory include file, there is no
reason to stick auto.conf.cmd optional. Make it mandatory as well.

Cc: linux-stable <stable@vger.kernel.org> # 5.0+
Fixes: 9390dff66a ("kbuild: invoke syncconfig if include/config/auto.conf.cmd is missing")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:54 +09:00
Masahiro Yamada
a149430434 kbuild: add all Clang-specific flags unconditionally
We do not support old Clang versions. Upgrade your clang version
if any of these flags is unsupported.

Let's add all flags inside ifdef CONFIG_CC_IS_CLANG unconditionally.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
2019-05-18 11:49:53 +09:00
Nathan Chancellor
7eb8e5f073 kbuild: Don't try to add '-fcatch-undefined-behavior' flag
This is no longer a valid option in clang, it was removed in 3.5, which
we don't support.

cb3f812b6b

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:53 +09:00
Masahiro Yamada
8289f913fe kbuild: add -Wvla flag unconditionally
This flag is documented in the GCC 4.6 manual, and recognized by
Clang as well. Let's rip off the cc-option switch.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
2019-05-18 11:49:52 +09:00
Masahiro Yamada
a3bc88645e kbuild: re-enable int-in-bool-context warning
This warning was disabled by commit bd664f6b3e ("disable new
gcc-7.1.1 warnings for now") just because it was too noisy.

Thanks to Arnd Bergmann, all warnings have been fixed. Now, we are
ready to re-enable it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-05-18 11:29:01 +09:00
Linus Torvalds
2646719a48 Kbuild updates for v5.2
- allow users to invoke 'make' out of the source tree
 
 - refactor scripts/mkmakefile
 
 - deprecate KBUILD_SRC, which was used to track the source tree
   location for O= build.
 
 - fix recordmcount.pl in case objdump output is localized
 
 - turn unresolved symbols in external modules to errors from warnings
   by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings
 
 - generate modules.builtin.modinfo to collect .modinfo data from
   built-in modules
 
 - misc Makefile cleanups
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Merge tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - allow users to invoke 'make' out of the source tree

 - refactor scripts/mkmakefile

 - deprecate KBUILD_SRC, which was used to track the source tree
   location for O= build.

 - fix recordmcount.pl in case objdump output is localized

 - turn unresolved symbols in external modules to errors from warnings
   by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings

 - generate modules.builtin.modinfo to collect .modinfo data from
   built-in modules

 - misc Makefile cleanups

* tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits)
  .gitignore: add more all*.config patterns
  moduleparam: Save information about built-in modules in separate file
  Remove MODULE_ALIAS() calls that take undefined macro
  .gitignore: add leading and trailing slashes to generated directories
  scripts/tags.sh: fix direct execution of scripts/tags.sh
  scripts: override locale from environment when running recordmcount.pl
  samples: kobject: allow CONFIG_SAMPLE_KOBJECT to become y
  samples: seccomp: turn CONFIG_SAMPLE_SECCOMP into a bool option
  kbuild: move Documentation to vmlinux-alldirs
  kbuild: move samples/ to KBUILD_VMLINUX_OBJS
  modpost: make KBUILD_MODPOST_WARN also configurable for external modules
  kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build
  kbuild: remove unneeded dependency for include/config/kernel.release
  memory: squash drivers/memory/Makefile.asm-offsets
  kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
  kbuild: mkmakefile: generate a simple wrapper of top Makefile
  kbuild: mkmakefile: do not check the generated Makefile marker
  kbuild: allow Kbuild to start from any directory
  kbuild: pass $(MAKECMDGOALS) to sub-make as is
  kbuild: fix warning "overriding recipe for target 'Makefile'"
  ...
2019-05-08 12:25:12 -07:00
Linus Torvalds
80f232121b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support AES128-CCM ciphers in kTLS, from Vakul Garg.

   2) Add fib_sync_mem to control the amount of dirty memory we allow to
      queue up between synchronize RCU calls, from David Ahern.

   3) Make flow classifier more lockless, from Vlad Buslov.

   4) Add PHY downshift support to aquantia driver, from Heiner
      Kallweit.

   5) Add SKB cache for TCP rx and tx, from Eric Dumazet. This reduces
      contention on SLAB spinlocks in heavy RPC workloads.

   6) Partial GSO offload support in XFRM, from Boris Pismenny.

   7) Add fast link down support to ethtool, from Heiner Kallweit.

   8) Use siphash for IP ID generator, from Eric Dumazet.

   9) Pull nexthops even further out from ipv4/ipv6 routes and FIB
      entries, from David Ahern.

  10) Move skb->xmit_more into a per-cpu variable, from Florian
      Westphal.

  11) Improve eBPF verifier speed and increase maximum program size,
      from Alexei Starovoitov.

  12) Eliminate per-bucket spinlocks in rhashtable, and instead use bit
      spinlocks. From Neil Brown.

  13) Allow tunneling with GUE encap in ipvs, from Jacky Hu.

  14) Improve link partner cap detection in generic PHY code, from
      Heiner Kallweit.

  15) Add layer 2 encap support to bpf_skb_adjust_room(), from Alan
      Maguire.

  16) Remove SKB list implementation assumptions in SCTP, your's truly.

  17) Various cleanups, optimizations, and simplifications in r8169
      driver. From Heiner Kallweit.

  18) Add memory accounting on TX and RX path of SCTP, from Xin Long.

  19) Switch PHY drivers over to use dynamic featue detection, from
      Heiner Kallweit.

  20) Support flow steering without masking in dpaa2-eth, from Ioana
      Ciocoi.

  21) Implement ndo_get_devlink_port in netdevsim driver, from Jiri
      Pirko.

  22) Increase the strict parsing of current and future netlink
      attributes, also export such policies to userspace. From Johannes
      Berg.

  23) Allow DSA tag drivers to be modular, from Andrew Lunn.

  24) Remove legacy DSA probing support, also from Andrew Lunn.

  25) Allow ll_temac driver to be used on non-x86 platforms, from Esben
      Haabendal.

  26) Add a generic tracepoint for TX queue timeouts to ease debugging,
      from Cong Wang.

  27) More indirect call optimizations, from Paolo Abeni"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1763 commits)
  cxgb4: Fix error path in cxgb4_init_module
  net: phy: improve pause mode reporting in phy_print_status
  dt-bindings: net: Fix a typo in the phy-mode list for ethernet bindings
  net: macb: Change interrupt and napi enable order in open
  net: ll_temac: Improve error message on error IRQ
  net/sched: remove block pointer from common offload structure
  net: ethernet: support of_get_mac_address new ERR_PTR error
  net: usb: smsc: fix warning reported by kbuild test robot
  staging: octeon-ethernet: Fix of_get_mac_address ERR_PTR check
  net: dsa: support of_get_mac_address new ERR_PTR error
  net: dsa: sja1105: Fix status initialization in sja1105_get_ethtool_stats
  vrf: sit mtu should not be updated when vrf netdev is the link
  net: dsa: Fix error cleanup path in dsa_init_module
  l2tp: Fix possible NULL pointer dereference
  taprio: add null check on sched_nest to avoid potential null pointer dereference
  net: mvpp2: cls: fix less than zero check on a u32 variable
  net_sched: sch_fq: handle non connected flows
  net_sched: sch_fq: do not assume EDT packets are ordered
  net: hns3: use devm_kcalloc when allocating desc_cb
  net: hns3: some cleanup for struct hns3_enet_ring
  ...
2019-05-07 22:03:58 -07:00
Linus Torvalds
2d60d96b6f compiler-based memory initialization
- Consolidate memory initialization Kconfigs (Kees)
 - Implement support for Clang's stack variable auto-init (Alexander)
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Merge tag 'meminit-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull compiler-based variable initialization updates from Kees Cook:
 "This is effectively part of my gcc-plugins tree, but as this adds some
  Clang support, it felt weird to still call it "gcc-plugins". :)

  This consolidates Kconfig for the existing stack variable
  initialization (via structleak and stackleak gcc plugins) and adds
  Alexander Potapenko's support for Clang's new similar functionality.

  Summary:

   - Consolidate memory initialization Kconfigs (Kees)

   - Implement support for Clang's stack variable auto-init (Alexander)"

* tag 'meminit-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  security: Implement Clang's stack initialization
  security: Move stackleak config to Kconfig.hardening
  security: Create "kernel hardening" config area
2019-05-07 12:44:49 -07:00
Linus Torvalds
573de2a6e8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching
Pull livepatching updates from Jiri Kosina:

 - livepatching kselftests improvements from Joe Lawrence and Miroslav
   Benes

 - making use of gcc's -flive-patching option when available, from
   Miroslav Benes

 - kobject handling cleanups, from Petr Mladek

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
  livepatch: Remove duplicated code for early initialization
  livepatch: Remove custom kobject state handling
  livepatch: Convert error about unsupported reliable stacktrace into a warning
  selftests/livepatch: Add functions.sh to TEST_PROGS_EXTENDED
  kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled
  selftests/livepatch: use TEST_PROGS for test scripts
2019-05-07 08:56:04 -07:00
Alexey Gladkov
898490c010 moduleparam: Save information about built-in modules in separate file
Problem:

When a kernel module is compiled as a separate module, some important
information about the kernel module is available via .modinfo section of
the module.  In contrast, when the kernel module is compiled into the
kernel, that information is not available.

Information about built-in modules is necessary in the following cases:

1. When it is necessary to find out what additional parameters can be
passed to the kernel at boot time.

2. When you need to know which module names and their aliases are in
the kernel. This is very useful for creating an initrd image.

Proposal:

The proposed patch does not remove .modinfo section with module
information from the vmlinux at the build time and saves it into a
separate file after kernel linking. So, the kernel does not increase in
size and no additional information remains in it. Information is stored
in the same format as in the separate modules (null-terminated string
array). Because the .modinfo section is already exported with a separate
modules, we are not creating a new API.

It can be easily read in the userspace:

$ tr '\0' '\n' < modules.builtin.modinfo
ext4.softdep=pre: crc32c
ext4.license=GPL
ext4.description=Fourth Extended Filesystem
ext4.author=Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others
ext4.alias=fs-ext4
ext4.alias=ext3
ext4.alias=fs-ext3
ext4.alias=ext2
ext4.alias=fs-ext2
md_mod.alias=block-major-9-*
md_mod.alias=md
md_mod.description=MD RAID framework
md_mod.license=GPL
md_mod.parmtype=create_on_open:bool
md_mod.parmtype=start_dirty_degraded:int
...

Co-Developed-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-07 21:50:24 +09:00
Linus Torvalds
e93c9c99a6 Linux 5.1 2019-05-05 17:42:58 -07:00
Masahiro Yamada
1eaca4b982 kbuild: move Documentation to vmlinux-alldirs
A minor code cleanup.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-03 23:04:59 +09:00
Masahiro Yamada
d93a18f27e kbuild: move samples/ to KBUILD_VMLINUX_OBJS
Handle samples/ like the other top-level directories to simplify
the Makefile.

Include include/config/auto.conf earlier to evaluate
drivers-$(CONFIG_SAMPLES).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-03 23:04:59 +09:00
David S. Miller
ff24e4980a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three trivial overlapping conflicts.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-02 22:14:21 -04:00
Linus Torvalds
6f303d6053 gcc-9: silence 'address-of-packed-member' warning
We already did this for clang, but now gcc has that warning too.  Yes,
yes, the address may be unaligned.  And that's kind of the point.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-01 11:05:41 -07:00
Linus Torvalds
37624b5854 Linux 5.1-rc7 2019-04-28 17:04:13 -07:00
David S. Miller
8b44836583 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two easy cases of overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-25 23:52:29 -04:00
Kees Cook
709a972efb security: Implement Clang's stack initialization
CONFIG_INIT_STACK_ALL turns on stack initialization based on
-ftrivial-auto-var-init in Clang builds, which has greater coverage
than CONFIG_GCC_PLUGINS_STRUCTLEAK_BYREF_ALL.

-ftrivial-auto-var-init Clang option provides trivial initializers for
uninitialized local variables, variable fields and padding.

It has three possible values:
  pattern - uninitialized locals are filled with a fixed pattern
    (mostly 0xAA on 64-bit platforms, see https://reviews.llvm.org/D54604
    for more details, but 0x000000AA for 32-bit pointers) likely to cause
    crashes when uninitialized value is used;
  zero (it's still debated whether this flag makes it to the official
    Clang release) - uninitialized locals are filled with zeroes;
  uninitialized (default) - uninitialized locals are left intact.

This patch uses only the "pattern" mode when CONFIG_INIT_STACK_ALL is
enabled.

Developers have the possibility to opt-out of this feature on a
per-variable basis by using __attribute__((uninitialized)), but such
use should be well justified in comments.

Co-developed-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Alexander Potapenko <glider@google.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-24 14:00:56 -07:00
Linus Torvalds
085b775580 Linux 5.1-rc6 2019-04-21 10:45:57 -07:00
David S. Miller
6b0a7f84ea Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflict resolution of af_smc.c from Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-17 11:26:25 -07:00
Linus Torvalds
dc4060a5dc Linux 5.1-rc5 2019-04-14 15:17:41 -07:00
David S. Miller
bb23581b9b Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-04-12

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Improve BPF verifier scalability for large programs through two
   optimizations: i) remove verifier states that are not useful in pruning,
   ii) stop walking parentage chain once first LIVE_READ is seen. Combined
   gives approx 20x speedup. Increase limits for accepting large programs
   under root, and add various stress tests, from Alexei.

2) Implement global data support in BPF. This enables static global variables
   for .data, .rodata and .bss sections to be properly handled which allows
   for more natural program development. This also opens up the possibility
   to optimize program workflow by compiling ELFs only once and later only
   rewriting section data before reload, from Daniel and with test cases and
   libbpf refactoring from Joe.

3) Add config option to generate BTF type info for vmlinux as part of the
   kernel build process. DWARF debug info is converted via pahole to BTF.
   Latter relies on libbpf and makes use of BTF deduplication algorithm which
   results in 100x savings compared to DWARF data. Resulting .BTF section is
   typically about 2MB in size, from Andrii.

4) Add BPF verifier support for stack access with variable offset from
   helpers and add various test cases along with it, from Andrey.

5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header
   so that L2 encapsulation can be used for tc tunnels, from Alan.

6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that
   users can define a subset of allowed __sk_buff fields that get fed into
   the test program, from Stanislav.

7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up
   various UBSAN warnings in bpftool, from Yonghong.

8) Generate a pkg-config file for libbpf, from Luca.

9) Dump program's BTF id in bpftool, from Prashant.

10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP
    program, from Magnus.

11) kallsyms related fixes for the case when symbols are not present in
    BPF selftests and samples, from Daniel
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-11 17:00:05 -07:00
Masahiro Yamada
a788b2ed81 kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build
After cross-compiling the kernel, "make mrproper" should be executed
with the proper ARCH= option. Otherwise, stale objects will remain
under arch/$(SRCARCH)/.

One bad scenario is like this:

  $ make ARCH=arm defconfig all   # cross-compile the kernel for arm
  $ make mrproper                 # mrproper for host-arch (i.e. x86)
  $ make ARCH=arm O=build_dir defconfig all

If you miss ARCH= for mrproper and cross-compile the kernel with O=
and ARCH= options, Kbuild will happily start to build, but may fail
due to stale objects in the srctree.

If $(srctree)/arch/$(SRCARCH)/include/generated/ exists, let's stop
the out-of-tree build. To detect this, mrproper should clean only
arch/$(SRCARCH)/include/generated/.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-09 22:51:56 +09:00
Masahiro Yamada
24512795df kbuild: remove unneeded dependency for include/config/kernel.release
This is unneeded since commit 43fee2b238 ("kbuild: do not redirect
the first prerequisite for filechk").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-09 22:51:53 +09:00
Miroslav Benes
43bd3a95c9 kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled
GCC 9 introduces a new option, -flive-patching. It disables certain
optimizations which could make a compilation unsafe for later live
patching of the running kernel.

The option is used only if CONFIG_LIVEPATCH is enabled and $(CC)
supports it.

Performance impact of the option was measured on three different
Intel machines - two bigger NUMA boxes and one smaller UMA box. Kernel
intensive (IO, scheduling, networking) benchmarks were selected, plus a
set of HPC workloads from NAS Parallel Benchmark. The tests were done on
upstream kernel 5.0-rc8 with openSUSE Leap 15.0 userspace.

The majority of the tests is unaffected. The only significant exception
is the scheduler section which suffers 1-3% degradation.

Evaluated-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-08 16:48:52 +02:00
Linus Torvalds
15ade5d2e7 Linux 5.1-rc4 2019-04-07 14:09:59 -10:00
Andrii Nakryiko
e83b9f5544 kbuild: add ability to generate BTF type info for vmlinux
This patch adds new config option to trigger generation of BTF type
information from DWARF debuginfo for vmlinux and kernel modules through
pahole, which in turn relies on libbpf for btf_dedup() algorithm.

The intent is to record compact type information of all types used
inside kernel, including all the structs/unions/typedefs/etc. This
enables BPF's compile-once-run-everywhere ([0]) approach, in which
tracing programs that are inspecting kernel's internal data (e.g.,
struct task_struct) can be compiled on a system running some kernel
version, but would be possible to run on other kernel versions (and
configurations) without recompilation, even if the layout of structs
changed and/or some of the fields were added, removed, or renamed.

This is only possible if BPF loader can get kernel type info to adjust
all the offsets correctly. This patch is a first time in this direction,
making sure that BTF type info is part of Linux kernel image in
non-loadable ELF section.

BTF deduplication ([1]) algorithm typically provides 100x savings
compared to DWARF data, so resulting .BTF section is not big as is
typically about 2MB in size.

[0] http://vger.kernel.org/lpc-bpf2018.html#session-2
[1] https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-03 00:53:07 +02:00
Masahiro Yamada
a9a49c2ad9 kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
KBUILD_SRC was conventionally used for some different purposes:
 [1] To remember the source tree path
 [2] As a flag to check if sub-make is already done
 [3] As a flag to check if Kbuild runs out of tree

For [1], we do not need to remember it because the top Makefile
can compute it by $(realpath $(dir $(lastword $(MAKEFILE_LIST))))

[2] has been replaced with self-commenting 'sub_make_done'.

For [3], we can distinguish in-tree/out-of-tree by comparing
$(srctree) and '.'

This commit converts [3] to prepare for the KBUILD_SRC removal.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-02 23:28:04 +09:00
Masahiro Yamada
25b146c5b8 kbuild: allow Kbuild to start from any directory
Kbuild always runs in the top of the output directory.

If Make starts in the source directory with O=, it relocates the
working directory to the location specified by O=.

Also, users can start build from the output directory by using the
Makefile generated by scripts/mkmakefile.

With a little more effort, Kbuild will be able to start from any
directory path.

This commit allows to specify the source directory by using
the -f option.

For example, you can do:

  $ cd path/to/output/dir
  $ make -f path/to/source/dir/Makefile

Or, for the equivalent behavior, you can do:

  $ make O=path/to/output/dir -f path/to/source/dir/Makefile

KBUILD_SRC is now deprecated.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kieran Bingham <kbingham@kernel.org>
2019-04-02 23:27:15 +09:00
Masahiro Yamada
6b1a9a02c7 kbuild: pass $(MAKECMDGOALS) to sub-make as is
Manipulating $(MAKECMDGOALS) for sub-make seems odd to me.

[1] 'make O=foo sub-make' is turned into 'make O=foo', which builds
the default targets. It would make sense to terminate the build with:

  *** No rule to make target 'sub-make'.  Stop.

[2] 'make O=foo defconfig _all' is turned into 'make O=foo defconfig',
which changes the behavior.

Let's pass $(MAKECMDGOALS) as is.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-01 10:06:00 +09:00
Masahiro Yamada
0209987fc8 kbuild: fix warning "overriding recipe for target 'Makefile'"
If you do "make Makefile" with GNU Make 3.x, the following warning
is displayed:

  $ make Makefile
  Makefile:165: warning: overriding recipe for target 'Makefile'
  Makefile:51: warning: ignoring old recipe for target 'Makefile'
  make[1]: Nothing to be done for 'Makefile'.
  make: Nothing to be done for 'Makefile'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-01 10:06:00 +09:00
Masahiro Yamada
669e06b19d kbuild: move RETPOLINE flags below config-targets
When you run a "make *config" target, the retpoline compiler flags
are evaluated for nothing because the code is located above the
'ifeq ($(config-targets),1)'.

Move it a bit below to avoid unneeded computation in the Kconfig stage.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-01 10:06:00 +09:00
Linus Torvalds
79a3aaa7b8 Linux 5.1-rc3 2019-03-31 14:39:29 -07:00
Linus Torvalds
f78b5be2a5 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core fixes from Thomas Gleixner:
 "A small set of core updates:

   - Make the watchdog respect the selected CPU mask again. That was
     broken by the rework of the watchdog thread management and caused
     inconsistent state and NMI watchdog being unstoppable.

   - Ensure that the objtool build can find the libelf location.

   - Remove dead kcore stub code"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  watchdog: Respect watchdog cpumask on CPU hotplug
  objtool: Query pkg-config for libelf location
  proc/kcore: Remove unused kclist_add_remap()
2019-03-31 07:47:21 -07:00
Linus Torvalds
0e40da3efe Kbuild fixes for v5.1
- Remove harmful -Oz option of Clang
 
  - Get back the original behavior (no recursion for in-tree build)
    for GNU Make 4.x
 
  - Some minor fixes for coccinelle patches
 
  - Do not overwrite .gitignore in the output directory in case
    it is version-controlled
 
  - Fix missed record-mcount bug for dynamic ftrace
 
  - Fix endianness bug in modversions for relative CRC
 
  - Cater to '^H' key code in Kconfig ncurses programs
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Merge tag 'kbuild-fixes-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Remove harmful -Oz option of Clang

 - Get back the original behavior (no recursion for in-tree build) for
   GNU Make 4.x

 - Some minor fixes for coccinelle patches

 - Do not overwrite .gitignore in the output directory in case it is
   version-controlled

 - Fix missed record-mcount bug for dynamic ftrace

 - Fix endianness bug in modversions for relative CRC

 - Cater to '^H' key code in Kconfig ncurses programs

* tag 'kbuild-fixes-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig/[mn]conf: handle backspace (^H) key
  kbuild: modversions: Fix relative CRC byte order interpretation
  scripts: coccinelle: Fix description of badty.cocci
  kbuild: strip whitespace in cmd_record_mcount findstring
  kbuild: do not overwrite .gitignore in output directory
  kbuild: skip parsing pre sub-make code for recursion
  coccinelle: put_device: reduce false positives
  kbuild: skip sub-make for in-tree build with GNU Make 4.x
  Revert "kbuild: use -Oz instead of -Os when using clang"
2019-03-29 14:46:00 -07:00
Masahiro Yamada
156e7cbb3e kbuild: do not overwrite .gitignore in output directory
Commit 3a51ff3442 ("kbuild: gitignore output directory") seemed to
bother people who version-control output directories.

Andre Przywara says:
"Unfortunately this breaks my setup, because I keep a totally separate
git repository in my build directories to track (various versions of)
.config. So .gitignore there is carefully crafted to ignore most build
artefacts, but not .config, for instance."

Link: https://lkml.org/lkml/2019/3/22/1819
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
2019-03-28 23:46:55 +09:00
Masahiro Yamada
221cc2d27d kbuild: skip parsing pre sub-make code for recursion
When Make recurses to the top Makefile with sub-make-done unset,
the code block surrounded by 'ifneq ($(sub-make-done),1) ... endif'
is parsed multiple times. This happens for in-tree building of
include/config/auto.conf, *-pkg, etc. with GNU Make 4.x.

This is a slight regression by commit 688931a5ad ("kbuild: skip
sub-make for in-tree build with GNU Make 4.x") in terms of performance
since that code block contains one $(shell ...) invocation.

Fix it by exporting the variable irrespective of sub-make being run.
I renamed it because GNU Make cannot properly export variables
containing hyphens. This is probably a bug of GNU Make, and the issue
in Kbuild had already been reported by commit 2bfbe7881e ("kbuild:
Do not use hyphen in exported variable name").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-28 23:46:54 +09:00
Rolf Eike Beer
056d28d135 objtool: Query pkg-config for libelf location
If it is not in the default location, compilation fails at several points.

Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/91a25e992566a7968fedc89ec80e7f4c83ad0548.1553622500.git.jpoimboe@redhat.com
2019-03-28 13:32:01 +01:00
Linus Torvalds
8c2ffd9174 Linux 5.1-rc2 2019-03-24 14:02:26 -07:00
Masahiro Yamada
688931a5ad kbuild: skip sub-make for in-tree build with GNU Make 4.x
Commit 2b50f7ab63 ("kbuild: add workaround for Debian make-kpkg")
annoyed people who want to wrap the top Makefile with GNUmakefile
to customize it for their use.

On second thought, we do not need to run the sub-make for in-tree
build with Make 4.x because the 'MAKEFLAGS += -rR' issue only happens
on GNU Make 3.x.

With this commit, people will get back their workflow, and the Debian
make-kpkg will still work.

Fixes: 2b50f7ab63 ("kbuild: add workaround for Debian make-kpkg")
Reported-by: Andreas Schwab <schwab@suse.de>
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Andreas Schwab <schwab@suse.de>
Tested-by: David Howells <dhowells@redhat.com>
2019-03-21 10:03:11 +09:00
Matthias Kaehlcke
a75bb4eb9e Revert "kbuild: use -Oz instead of -Os when using clang"
The clang option -Oz enables *aggressive* optimization for size,
which doesn't necessarily result in smaller images, but can have
negative impact on performance. Switch back to the less aggressive
-Os.

This reverts commit 6748cb3c29.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-20 22:27:29 +09:00
Linus Torvalds
9e98c678c2 Linux 5.1-rc1 2019-03-17 14:22:26 -07:00
Masahiro Yamada
037fc3368b kbuild: force all architectures except um to include mandatory-y
Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes
the common Kbuild.asm file. Factor out the duplicated include directives
to scripts/Makefile.asm-generic so that no architecture would opt out
of the mandatory-y mechanism.

um is not forced to include mandatory-y since it is a very exceptional
case which does not support UAPI.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-17 12:56:32 +09:00
Douglas Anderson
0c22be0712 kbuild: Make NOSTDINC_FLAGS a simply expanded variable
During a simple no-op (nothing changed) build I saw 39 invocations of
the C compiler with the argument "-print-file-name=include".  We don't
need to call the C compiler 39 times for this--one time will suffice.

Let's change NOSTDINC_FLAGS to a simply expanded variable to avoid
this since there doesn't appear to be any reason it should be
recursively expanded.

On my build this shaved ~400 ms off my "no-op" build.

Note that the recursive expansion seems to date back to the (really
old) commit e8f5bdb02c ("[PATCH] Makefile include path ordering").
It's a little unclear to me if the point of that patch was to switch
the variable to be recursively expanded (which it did) or to avoid
directly assigning to NOSTDINC_FLAGS (AKA to switch to +=) because
someone else (out of tree?) was setting it.  I presume later since if
the only goal was to switch to recursive expansion the patch would
have just removed the ":".

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-17 12:56:30 +09:00
Masahiro Yamada
2b50f7ab63 kbuild: add workaround for Debian make-kpkg
Since commit 3812b8c5c5 ("kbuild: make -r/-R effective in top
Makefile for old Make versions"), make-kpkg is not working.

make-kpkg directly includes the top Makefile of Linux kernel, and
appends some debian_* targets.

  /usr/share/kernel-package/ruleset/kernel_version.mk:

    # Include the kernel makefile
    override dot-config := 1
    include Makefile
    dot-config := 1

I did not know the kernel Makefile was used in that way, and it is
hard to guarantee the behavior when the kernel Makefile is included
by another Makefile from a different project.

It looks like Debian Stretch stopped providing make-kpkg. Maybe it is
obsolete and being replaced with 'make deb-pkg' etc. but still widely
used.

This commit adds a workaround; if the top Makefile is included by
another Makefile, skip sub-make in order to make the main part visible.
'MAKEFLAGS += -rR' does not become effective for GNU Make < 4.0, but
Debian/Ubuntu is already using newer versions.

The effect of this commit:

  Debian 8 (Jessie)  : Fixed
  Debian 9 (Stretch) : make-kpkg (kernel-package) is not provided
  Ubuntu 14.04 LTS   : NOT Fixed
  Ubuntu 16.04 LTS   : Fixed
  Ubuntu 18.04 LTS   : Fixed

This commit cannot fix Ubuntu 14.04 because it installs GNU Make 3.81,
but its support will end in Apr 2019, which is before the Linux v5.1
release.

I added warning so that nobody would try to include the top Makefile.

Fixes: 3812b8c5c5 ("kbuild: make -r/-R effective in top Makefile for old Make versions")
Reported-by: Liz Zhang <lizzha@microsoft.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Lili Deng <v-lide@microsoft.com>
Cc: Manoj Srivastava <srivasta@debian.org>
2019-03-14 02:39:12 +09:00