5946 Commits

Author SHA1 Message Date
Masahiro Yamada
48a0f72797 modpost: show warning if any of symbol dump files is missing
If modpost fails to load a symbol dump file, it cannot check unresolved
symbols, hence module dependency will not be added. Nor CRCs can be added.

Currently, external module builds check only $(objtree)/Module.symvers,
but it should check files specified by KBUILD_EXTRA_SYMBOLS as well.

Move the warning message from the top Makefile to scripts/Makefile.modpost
and print the warning if any dump file is missing.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
7e8a323582 modpost: show warning if vmlinux is not found when processing modules
check_exports() does not print warnings about unresolved symbols if
vmlinux is missing because there would be too many.

This situation happens when you do 'make modules' from the clean
tree, or compile external modules against a kernel tree that has
not been completely built.

It is dangerous to not check unresolved symbols because you might be
building useless modules. At least it should be warned.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
436b2ac603 modpost: invoke modpost only when input files are updated
Currently, the second pass of modpost is always invoked when you run
'make' or 'make modules' even if none of modules is changed.

Use if_changed to invoke it only when it is necessary.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
269a535ca9 modpost: generate vmlinux.symvers and reuse it for the second modpost
The full build runs modpost twice, first for vmlinux.o and second for
modules.

The first pass dumps all the vmlinux symbols into Module.symvers, but
the second pass parses vmlinux again instead of reusing the dump file,
presumably because it needs to avoid accumulating stale symbols.

Loading symbol info from a dump file is faster than parsing an ELF object.
Besides, modpost deals with various issues to parse vmlinux in the second
pass.

A solution is to make the first pass dumps symbols into a separate file,
vmlinux.symvers. The second pass reads it, and parses module .o files.
The merged symbol information is dumped into Module.symvers in the same
way as before.

This makes further modpost cleanups possible.

Also, it fixes the problem of 'make vmlinux', which previously overwrote
Module.symvers, throwing away module symbols.

I slightly touched scripts/link-vmlinux.sh so that vmlinux is re-linked
when you cross this commit. Otherwise, vmlinux.symvers would not be
generated.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
f1005b30ad modpost: refactor -i option calculation
Prepare to use -i for in-tree modpost as well.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
bcfedae7d9 modpost: print symbol dump file as the build target in short log
The symbol dump *.symvers is the output of modpost. Print it in
the short log.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
e3fb4df7fe modpost: re-add -e to set external_module flag
Previously, the -i option had two functions; load a symbol dump file,
and set the external_module flag.

I want to assign a dedicate option for each of them.

Going forward, the -i is used to load a symbol dump file, and the -e
to set the external_module flag.

With this, we will be able to use -i for loading in-kernel symbols.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
7924799ed2 modpost: rename ext_sym_list to dump_list
The -i option is used to include Modules.symver as well as files from
$(KBUILD_EXTRA_SYMBOLS).

Make the struct and variable names more generic.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
ce2ddd6d6a modpost: allow to pass -i option multiple times to remove -e option
Now that there is no difference between -i and -e, they can be unified.

Make modpost accept the -i option multiple times, then remove -e.

I will reuse -e for a different purpose.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
52c3416db0 modpost: track if the symbol origin is a dump file or ELF object
The meaning of sym->kernel is obscure; it is set for in-kernel symbols
loaded from Modules.symvers. This happens only when we are building
external modules, and it is used to determine whether to dump symbols
to $(KBUILD_EXTMOD)/Modules.symvers

It is clearer to remember whether the symbol or module came from a dump
file or ELF object.

This changes the KBUILD_EXTRA_SYMBOLS behavior. Previously, symbols
loaded from KBUILD_EXTRA_SYMBOLS are accumulated into the current
$(KBUILD_EXTMOD)/Modules.symvers

Going forward, they will be only used to check symbol references, but
not dumped into the current $(KBUILD_EXTMOD)/Modules.symvers. I believe
this makes more sense.

sym->vmlinux will have no user. Remove it too.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:36:55 +09:00
Erwan Velu
f5152f4ded firmware/dmi: Report DMI Bios & EC firmware release
Some vendors like HPe or Dell, encode the release version of their BIOS
in the "System BIOS {Major|Minor} Release" fields of Type 0.

This information is used to know which bios release actually runs.
It could be used for some quirks, debugging sessions or inventory tasks.

A typical output for a Dell system running the 65.27 bios is :
	[root@t1700 ~]# cat /sys/devices/virtual/dmi/id/bios_release
	65.27
	[root@t1700 ~]#

Servers that have a BMC encode the release version of their firmware in the
 "Embedded Controller Firmware {Major|Minor} Release" fields of Type 0.

This information is used to know which BMC release actually runs.
It could be used for some quirks, debugging sessions or inventory tasks.

A typical output for a Dell system running the 3.75 bmc release is :
    [root@t1700 ~]# cat /sys/devices/virtual/dmi/id/ec_firmware_release
    3.75
    [root@t1700 ~]#

Signed-off-by: Erwan Velu <e.velu@criteo.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
2020-06-06 11:35:50 +02:00
Linus Torvalds
571d54ed91 Devicetree updates for v5.8:
- Convert various DT (non-binding) doc files to ReST
 
 - Various improvements to device link code
 
 - Fix __of_attach_node_sysfs refcounting bug
 
 - Add support for 'memory-region-names' with reserved-memory binding
 
 - Vendor prefixes for Protonic Holland, BeagleBoard.org, Alps, Check
   Point, Würth Elektronik, U-Boot, Vaisala, Baikal Electronics, Shanghai
   Awinic Technology Co., MikroTik, Silex Insight
 
 - A bunch more binding conversions to DT schema. Only 3K to go.
 
 - Add a minimum version check for schema tools
 
 - Treewide dropping of 'allOf' usage with schema references. Not needed
   in new json-schema spec.
 
 - Some formatting clean-ups of schemas
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Merge tag 'devicetree-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:

 - Convert various DT (non-binding) doc files to ReST

 - Various improvements to device link code

 - Fix __of_attach_node_sysfs refcounting bug

 - Add support for 'memory-region-names' with reserved-memory binding

 - Vendor prefixes for Protonic Holland, BeagleBoard.org, Alps, Check
   Point, Würth Elektronik, U-Boot, Vaisala, Baikal Electronics,
   Shanghai Awinic Technology Co., MikroTik, Silex Insight

 - A bunch more binding conversions to DT schema. Only 3K to go.

 - Add a minimum version check for schema tools

 - Treewide dropping of 'allOf' usage with schema references. Not needed
   in new json-schema spec.

 - Some formatting clean-ups of schemas

* tag 'devicetree-for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (194 commits)
  dt-bindings: clock: Add documentation for X1830 bindings.
  dt-bindings: mailbox: Convert imx mu to json-schema
  dt-bindings: power: Convert imx gpcv2 to json-schema
  dt-bindings: power: Convert imx gpc to json-schema
  dt-bindings: Merge gpio-usb-b-connector with usb-connector
  dt-bindings: timer: renesas: cmt: Convert to json-schema
  dt-bindings: clock: Convert i.MX8QXP LPCG to json-schema
  dt-bindings: timer: Convert i.MX GPT to json-schema
  dt-bindings: thermal: rcar-thermal: Add device tree support for r8a7742
  dt-bindings: serial: Add binding for UART pin swap
  dt-bindings: geni-se: Add interconnect binding for GENI QUP
  dt-bindings: geni-se: Convert QUP geni-se bindings to YAML
  dt-bindings: vendor-prefixes: Add Silex Insight vendor prefix
  dt-bindings: input: touchscreen: edt-ft5x06: change reg property
  dt-bindings: usb: qcom,dwc3: Introduce interconnect properties for Qualcomm DWC3 driver
  dt-bindings: timer: renesas: mtu2: Convert to json-schema
  of/fdt: Remove redundant kbasename function call
  dt-bindings: clock: Convert i.MX1 clock to json-schema
  dt-bindings: clock: Convert i.MX21 clock to json-schema
  dt-bindings: clock: Convert i.MX25 clock to json-schema
  ...
2020-06-04 20:11:25 -07:00
Geert Uytterhoeven
c7f574d0e9 checkpatch: use patch subject when reading from stdin
While "git am" can apply an mbox file containing multiple patches (e.g.
as created by b4[1], or a patch bundle downloaded from patchwork),
checkpatch does not have proper support for that.  When operating on an
mbox, checkpatch will merge all detected tags, and complain falsely about
duplicates:

    WARNING: Duplicate signature

As modifying checkpatch to reset state in between each patch is a lot of
work, a simple solution is splitting the mbox into individual patches, and
invoking checkpatch for each of them.  Fortunately checkpatch can read a
patch from stdin, so the classic "formail" tool can be used to split the
mbox, and pipe all individual patches to checkpatch:

    formail -s scripts/checkpatch.pl < my-mbox

However, when reading a patch file from standard input, checkpatch calls
it "Your patch", and reports its state as:

    Your patch has style problems, please review.

or:

    Your patch has no obvious style problems and is ready for submission.

Hence it can be difficult to identify which patches need to be reviewed
and improved.

Fix this by replacing "Your patch" by (the first line of) the email
subject, if present.

Note that "git mailsplit" can also be used to split an mbox, but it will
create individual files for each patch, thus requiring cleanup afterwards.
Formail does not have this disadvantage.

[1] https://git.kernel.org/pub/scm/utils/b4/b4.git

[joe@perches.com: reduce cpu usage]
  Link: http://lkml.kernel.org/r/c9d89bb24c7414142414c60371e210fdcf4617d2.camel@perches.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200505132613.17452-1-geert+renesas@glider.be
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
Joe Perches
32f30ca9f1 checkpatch: disallow --git and --file/--fix
Don't allow these options to be combined.

Miscellanea:

o Add missing $P: to some die("reason message") output

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/3dc7bdaa58490f5906efc11a4d6113e42a087723.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
Joe Perches
a55ee0cc09 checkpatch: look for c99 comments in ctx_locate_comment
Some checks look for comments around a specific function like
read_barrier_depends.

Extend the check to support both c89 and c90 comment styles.

	c89 /* comment */
or
	c99 // comment

For c99 comments, only look a 3 single lines, the line being scanned,
the line above and the line below the line being scanned rather than
the patch diff context.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/65cb075435d2f385a53c77571b491b2b09faaf8e.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
Joe Perches
7ccf41a89c checkpatch: additional MAINTAINER section entry ordering checks
There is a preferred order for the entries in MAINTAINERS sections.

See commits 3b50142d8528 ("MAINTAINERS: sort field names for all
entries") and 6680125ea5a2 ("MAINTAINERS: list the section entries in
the preferred order")

Add checkpatch tests to try to keep that ordering.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: http://lkml.kernel.org/r/17677130b3ca62d79817e6a22546bad39d7e81b4.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
Joe Perches
e33c9fe8b8 get_maintainer: fix unexpected behavior for path/to//file (double slashes)
get_maintainer behaves differently if there is a double sequential forward
slash in a filename because the total number of slashes in a filename is
used to match MAINTAINERS file patterns.

For example:

(with double slash)
  $ ./scripts/get_maintainer.pl -f drivers/gpu/drm//lima
  David Airlie <airlied@linux.ie> (maintainer:DRM DRIVERS)
  Daniel Vetter <daniel@ffwll.ch> (maintainer:DRM DRIVERS,commit_signer:3/42=7%)
  Qiang Yu <yuq825@gmail.com> (commit_signer:36/42=86%,authored:24/42=57%)
  Vasily Khoruzhick <anarsoul@gmail.com> (commit_signer:26/42=62%)
  Krzysztof Kozlowski <krzk@kernel.org> (commit_signer:5/42=12%,authored:5/42=12%)
  Emil Velikov <emil.velikov@collabora.com> (commit_signer:4/42=10%)
  dri-devel@lists.freedesktop.org (open list:DRM DRIVERS)
  linux-kernel@vger.kernel.org (open list)

(without double slash)
  $ ./scripts/get_maintainer.pl -f drivers/gpu/drm/lima
  Qiang Yu <yuq825@gmail.com> (maintainer:DRM DRIVERS FOR LIMA)
  David Airlie <airlied@linux.ie> (maintainer:DRM DRIVERS)
  Daniel Vetter <daniel@ffwll.ch> (maintainer:DRM DRIVERS)
  dri-devel@lists.freedesktop.org (open list:DRM DRIVERS FOR LIMA)
  lima@lists.freedesktop.org (moderated list:DRM DRIVERS FOR LIMA)
  linux-kernel@vger.kernel.org (open list)

So reduce consecutive double slashes to a single slash
by using File::Spec->canonpath().

from: https://perldoc.perl.org/File/Spec/Unix.html

canonpath()

No physical check on the filesystem, but a logical cleanup of a path.  On
UNIX eliminates successive slashes and successive "/.".

Reported-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/9a18b611813bb409fef15bc8927adab79eb9be43.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:24 -07:00
Joe Perches
0c78c01376 get_maintainer: add email addresses from .yaml files
.yaml files can contain maintainer/author addresses and it seems unlikely
or unnecessary that individual MAINTAINER file section entries for each
.yaml file will be created.

So add the email addresses found in .yaml files to the default
get_maintainer output.

The email addresses are marked with "(in file)" when using the "--roles"
or "--rolestats" options.

Miscellanea:

o Change $file_emails to $email_file_emails to avoid visual
  naming conflicts with @file_emails

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: http://lkml.kernel.org/r/e85006456d9dbae55286c67ac5263668a72f5b58.1588022228.git.joe@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:24 -07:00
Linus Torvalds
cb8e59cc87 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
    Augusto von Dentz.

 2) Add GSO partial support to igc, from Sasha Neftin.

 3) Several cleanups and improvements to r8169 from Heiner Kallweit.

 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
    device self-test. From Andrew Lunn.

 5) Start moving away from custom driver versions, use the globally
    defined kernel version instead, from Leon Romanovsky.

 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.

 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.

 8) Add sriov and vf support to hinic, from Luo bin.

 9) Support Media Redundancy Protocol (MRP) in the bridging code, from
    Horatiu Vultur.

10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.

11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
    Dubroca. Also add ipv6 support for espintcp.

12) Lots of ReST conversions of the networking documentation, from Mauro
    Carvalho Chehab.

13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
    from Doug Berger.

14) Allow to dump cgroup id and filter by it in inet_diag code, from
    Dmitry Yakunin.

15) Add infrastructure to export netlink attribute policies to
    userspace, from Johannes Berg.

16) Several optimizations to sch_fq scheduler, from Eric Dumazet.

17) Fallback to the default qdisc if qdisc init fails because otherwise
    a packet scheduler init failure will make a device inoperative. From
    Jesper Dangaard Brouer.

18) Several RISCV bpf jit optimizations, from Luke Nelson.

19) Correct the return type of the ->ndo_start_xmit() method in several
    drivers, it's netdev_tx_t but many drivers were using
    'int'. From Yunjian Wang.

20) Add an ethtool interface for PHY master/slave config, from Oleksij
    Rempel.

21) Add BPF iterators, from Yonghang Song.

22) Add cable test infrastructure, including ethool interfaces, from
    Andrew Lunn. Marvell PHY driver is the first to support this
    facility.

23) Remove zero-length arrays all over, from Gustavo A. R. Silva.

24) Calculate and maintain an explicit frame size in XDP, from Jesper
    Dangaard Brouer.

25) Add CAP_BPF, from Alexei Starovoitov.

26) Support terse dumps in the packet scheduler, from Vlad Buslov.

27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.

28) Add devm_register_netdev(), from Bartosz Golaszewski.

29) Minimize qdisc resets, from Cong Wang.

30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
    eliminate set_fs/get_fs calls. From Christoph Hellwig.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
  selftests: net: ip_defrag: ignore EPERM
  net_failover: fixed rollback in net_failover_open()
  Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
  Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
  vmxnet3: allow rx flow hash ops only when rss is enabled
  hinic: add set_channels ethtool_ops support
  selftests/bpf: Add a default $(CXX) value
  tools/bpf: Don't use $(COMPILE.c)
  bpf, selftests: Use bpf_probe_read_kernel
  s390/bpf: Use bcr 0,%0 as tail call nop filler
  s390/bpf: Maintain 8-byte stack alignment
  selftests/bpf: Fix verifier test
  selftests/bpf: Fix sample_cnt shared between two threads
  bpf, selftests: Adapt cls_redirect to call csum_level helper
  bpf: Add csum_level helper for fixing up csum levels
  bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
  sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
  crypto/chtls: IPv6 support for inline TLS
  Crypto/chcr: Fixes a coccinile check error
  Crypto/chcr: Fixes compilations warnings
  ...
2020-06-03 16:27:18 -07:00
Masahiro Yamada
2beee86899 modpost: load KBUILD_EXTRA_SYMBOLS files in order
Currently, modpost reads extra symbol dump files in the reverse order.
If '-e foo -e bar' is given, modpost reads bar, foo, in this order.

This is probably not a big deal, but there is no good reason to reverse
the order. Read files in the given order.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:18 +09:00
Masahiro Yamada
4e5ab74c3c modpost: pass -N option only for modules modpost
The built-in only code is not required to have MODULE_IMPORT_NS() to
use symbols. So, the namespace is not checked for vmlinux(.o).

Do not pass the meaningless -N option to the first pass of modpost.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:17 +09:00
Masahiro Yamada
89d6117680 modpost: move -T option close to the modpost command
The '-T -' option reads the file list from stdin.

It is clearer to put it close to the piped command.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:17 +09:00
Masahiro Yamada
91e6ee5812 modpost: fix -i (--ignore-errors) MAKEFLAGS detection
$(filter -i,$(MAKEFLAGS)) works only in limited use-cases.

The representation of $(MAKEFLAGS) depends on various factors:
  - GNU Make version (version 3.8x or version 4.x)
  - The presence of other flags like -j

In my experiments, $(MAKEFLAGS) is expanded as follows:

  * GNU Make 3.8x:

    * without -j option:
      --no-print-directory -Rri

    * with -j option:
      --no-print-directory -Rr --jobserver-fds=3,4 -j -i

  * GNU Make 4.x:

    * without -j option:
      irR --no-print-directory

    * with -j option:
      irR -j --jobserver-fds=3,4 --no-print-directory

For GNU Make 4.x, the flags are grouped as 'irR', which does not work.

For the single thread build with GNU Make 3.8x, the flags are grouped
as '-Rri', which does not work either.

To make it work for all cases, do likewise as commit 6f0fa58e4596
("kbuild: simplify silent build (-s) detection").

BTW, since commit ff9b45c55b26 ("kbuild: modpost: read modules.order
instead of $(MODVERDIR)/*.mod"), you also need to pass -k option to
build final *.ko files. 'make -i -k' ignores compile errors in modules,
and build as many remaining *.ko as possible.

Please note this feature is kind of dangerous if other modules depend
on the broken module because the generated modules will lack the correct
module dependency or CRC. Honestly, I am not a big fan of it, but I am
keeping this feature.

Fixes: eed380f3f593 ("modpost: Optionally ignore secondary errors seen if a single module build fails")
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:17 +09:00
Masahiro Yamada
b2c8855491 kbuild: update modules.order only when contained modules are updated
Make modules.order depend on $(obj-m), and use if_changed to build it.
This will avoid unneeded update of modules.order, which will be useful
to optimize the modpost stage.

Currently, the second pass of modpost is always invoked. By checking the
timestamp of modules.order, we can avoid the unneeded modpost.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:17 +09:00
Linus Torvalds
b23c4771ff A fair amount of stuff this time around, dominated by yet another massive
set from Mauro toward the completion of the RST conversion.  I *really*
 hope we are getting close to the end of this.  Meanwhile, those patches
 reach pretty far afield to update document references around the tree;
 there should be no actual code changes there.  There will be, alas, more of
 the usual trivial merge conflicts.
 
 Beyond that we have more translations, improvements to the sphinx
 scripting, a number of additions to the sysctl documentation, and lots of
 fixes.
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Merge tag 'docs-5.8' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
Linus Torvalds
69fc06f70f There are a lot of objtool changes in this cycle, all across the map:
- Speed up objtool significantly, especially when there are large number of sections
  - Improve objtool's understanding of special instructions such as IRET,
    to reduce the number of annotations required
  - Implement 'noinstr' validation
  - Do baby steps for non-x86 objtool use
  - Simplify/fix retpoline decoding
  - Add vmlinux validation
  - Improve documentation
  - Fix various bugs and apply smaller cleanups
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'objtool-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:
 "There are a lot of objtool changes in this cycle, all across the map:

   - Speed up objtool significantly, especially when there are large
     number of sections

   - Improve objtool's understanding of special instructions such as
     IRET, to reduce the number of annotations required

   - Implement 'noinstr' validation

   - Do baby steps for non-x86 objtool use

   - Simplify/fix retpoline decoding

   - Add vmlinux validation

   - Improve documentation

   - Fix various bugs and apply smaller cleanups"

* tag 'objtool-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  objtool: Enable compilation of objtool for all architectures
  objtool: Move struct objtool_file into arch-independent header
  objtool: Exit successfully when requesting help
  objtool: Add check_kcov_mode() to the uaccess safelist
  samples/ftrace: Fix asm function ELF annotations
  objtool: optimize add_dead_ends for split sections
  objtool: use gelf_getsymshndx to handle >64k sections
  objtool: Allow no-op CFI ops in alternatives
  x86/retpoline: Fix retpoline unwind
  x86: Change {JMP,CALL}_NOSPEC argument
  x86: Simplify retpoline declaration
  x86/speculation: Change FILL_RETURN_BUFFER to work with objtool
  objtool: Add support for intra-function calls
  objtool: Move the IRET hack into the arch decoder
  objtool: Remove INSN_STACK
  objtool: Make handle_insn_ops() unconditional
  objtool: Rework allocating stack_ops on decode
  objtool: UNWIND_HINT_RET_OFFSET should not check registers
  objtool: is_fentry_call() crashes if call has no destination
  x86,smap: Fix smap_{save,restore}() alternatives
  ...
2020-06-01 13:13:00 -07:00
Linus Torvalds
0bd957eb11 Various kprobes updates, mostly centered around cleaning up the no-instrumentation
logic, instead of the current per debug facility blacklist, use the more generic
 .noinstr.text approach, combined with a 'noinstr' marker for functions.
 
 Also add instrumentation_begin()/end() to better manage the exact place in entry
 code where instrumentation may be used.
 
 Also add a kprobes blacklist for modules.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'core-kprobes-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull kprobes updates from Ingo Molnar:
 "Various kprobes updates, mostly centered around cleaning up the
  no-instrumentation logic.

  Instead of the current per debug facility blacklist, use the more
  generic .noinstr.text approach, combined with a 'noinstr' marker for
  functions.

  Also add instrumentation_begin()/end() to better manage the exact
  place in entry code where instrumentation may be used.

  And add a kprobes blacklist for modules"

* tag 'core-kprobes-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kprobes: Prevent probes in .noinstr.text section
  vmlinux.lds.h: Create section for protection against instrumentation
  samples/kprobes: Add __kprobes and NOKPROBE_SYMBOL() for handlers.
  kprobes: Support NOKPROBE_SYMBOL() in modules
  kprobes: Support __kprobes blacklist in modules
  kprobes: Lock kprobe_mutex while showing kprobe_blacklist
2020-06-01 12:45:04 -07:00
Arnd Bergmann
37744feebc sh: remove sh5 support
sh5 never became a product and has probably never really worked.

Remove it by recursively deleting all associated Kconfig options
and all corresponding files.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rich Felker <dalias@libc.org>
2020-06-01 14:48:52 -04:00
Masahiro Yamada
f3908ab3ff kbuild: refactor tagets caluculation for KBUILD_{BUILTIN,KBUILD_MODULES}
Remove lib-target, builtin-target, modorder-target, and modtargets.

Instead, add targets-for-builtin and targets-for-modules.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-01 21:50:46 +09:00
Masahiro Yamada
0a8820e7f8 kbuild: refactor subdir-ym calculation
Remove the unneeded variables, __subdir-y and __subdir-m.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-01 21:50:45 +09:00
David S. Miller
1806c13dc2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
xdp_umem.c had overlapping changes between the 64-bit math fix
for the calculation of npgs and the removal of the zerocopy
memory type which got rid of the chunk_size_nohdr member.

The mlx5 Kconfig conflict is a case where we just take the
net-next copy of the Kconfig entry dependency as it takes on
the ESWITCH dependency by one level of indirection which is
what the 'net' conflicting change is trying to ensure.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-31 17:48:46 -07:00
Joe Perches
bdc48fa11e checkpatch/coding-style: deprecate 80-column warning
Yes, staying withing 80 columns is certainly still _preferred_.  But
it's not the hard limit that the checkpatch warnings imply, and other
concerns can most certainly dominate.

Increase the default limit to 100 characters.  Not because 100
characters is some hard limit either, but that's certainly a "what are
you doing" kind of value and less likely to be about the occasional
slightly longer lines.

Miscellanea:

 - to avoid unnecessary whitespace changes in files, checkpatch will no
   longer emit a warning about line length when scanning files unless
   --strict is also used

 - Add a bit to coding-style about alignment to open parenthesis

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-31 11:00:42 -07:00
Masahiro Yamada
565587d8d5 modpost: refactor sech_name()
Use sym_get_data_by_offset() helper to get access to the .shstrtab
section data. No functional change is intended because
elf->sechdrs[elf->secindex_strings].sh_addr is 0 for both ET_REL
and ET_EXEC object types.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Masahiro Yamada
d2e4d05cf1 modpost: fix potential segmentation fault for addend_i386_rel()
This may not be a practical problem, but the second pass of ARCH=i386
modpost causes segmentation fault if the -s option is not passed.

    MODPOST 12 modules
  Segmentation fault (core dumped)
  make[2]: *** [scripts/Makefile.modpost:94: __modpost] Error 139
  make[1]: *** [Makefile:1339: modules] Error 2
  make[1]: *** Waiting for unfinished jobs....

The segmentation fault occurs when section_rel() is called for vmlinux,
which is untested in regular builds. The cause of the problem is
reloc_location() returning a wrong pointer for ET_EXEC object type.
In this case, you need to subtract sechdr->sh_addr, otherwise it would
get access beyond the mmap'ed memory.

Add sym_get_data_by_offset() helper to avoid code duplication.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Masahiro Yamada
e9e81b6343 kbuild: disallow multi-word in M= or KBUILD_EXTMOD
$(firstword ...) in scripts/Makefile.modpost was added by commit
3f3fd3c05585 ("[PATCH] kbuild: allow multi-word $M in Makefile.modpost")
to build multiple external module directories.

It was a solution to resolve symbol dependencies when an external
module depends on another external module.

Commit 0d96fb20b7ed ("kbuild: Add new Kbuild variable
KBUILD_EXTRA_SYMBOLS") introduced another solution by passing symbol
info via KBUILD_EXTRA_SYMBOLS, then broke the multi-word M= support.

  include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \
               $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile)

... does not work if KBUILD_EXTMOD contains multiple words.

This feature has been broken for more than a decade. Remove the
bitrotten code, and stop parsing if M or KBUILD_EXTMOD contains
multiple words.

As Documentation/kbuild/modules.rst explains, if your module depends
on another one, there are two solutions:
  - add a common top-level Kbuild file
  - use KBUILD_EXTRA_SYMBOLS

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Masahiro Yamada
454753d9f6 kbuild: make modules.order rule consistent with built-in.a
built-in.a contains the built-in object paths from the current and sub
directories.

module.order collects the module paths from the current and sub
directories.

Make their build rules look more symmetrical.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
aaa385ba9a kbuild: rename subdir-obj-y to subdir-builtin
I think subdir-builtin is clearer.

While I was here, I made its build rule explicit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
6ba3bcb013 kbuild: move subdir-obj-y to scripts/Makefile.build
Save $(addprefix ...) for subdir-obj-y.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
b480fec988 kbuild: clear KBUILD_MODULES in top Makefile if CONFIG_MODULES=n
Do not try to build any module-related artifacts when CONFIG_MODULES
is disabled.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
e578edc722 kbuild: remove ifdef builtin-target / lib-target
I do not see a good reason to add ifdef here.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
8451791d1f kbuild: make module name conflict fatal error
I think all the warnings have been fixed by now. Make it a fatal error.

Check it before modpost because we need to stop building *.ko files.
Also, pass modules.order via a script parameter.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
827365ffda gcc-plugins: remove always-false $(if ...) in Makefile
This is the remnant of commit c17d6179ad5a ("gcc-plugins: remove unused
GCC_PLUGIN_SUBDIR").

The conditional $(if $(findstring /,$(p)),...) is always false because
none of plugins contains '/' in the file name.

Clean up the code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
6ce16f2bc8 scripts/checkstack.pl: fix arm sp regex
if objdump has below entries;
c01ed608 <X>:
c01ed614:       e24ddff7        sub     sp, sp, #120    ; 0x78

c01f0d50 <Y>:
c01f0d50:       e24dd094        sub     sp, sp, #140    ; 0x8c

scripts fails to read stack usage.
so making regex $re for ARM similar to aarch64

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
3311eeebae scripts/checkstack.pl: add arm push handling for stack usage
To count stack usage of push {*, fp, ip, lr, pc} instruction in ARM,
if FRAME POINTER is enabled.
e.g. c01f0d48: e92ddff0 push {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}

c01f0d50 <Y>:
c01f0d44:       e1a0c00d        mov     ip, sp
c01f0d48:       e92ddff0        push    {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}
c01f0d4c:       e24cb004        sub     fp, ip, #4
c01f0d50:       e24dd094        sub     sp, sp, #448    ; 0x1C0

$ cat dump | scripts/checkstack.pl arm
0xc01f0d50 Y []:                                        448

added subroutine frame work for this.
After change:
0xc01f0d500 Y []:                                       492

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
572220aad5 scripts/checkstack.pl: Add argument to print stacks greather than value.
Add arguments support to print stacks which are greater than
argument value only.

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Maninder Singh
677f1410e0 scripts/checkstack.pl: don't display $dre as different entity
currently script prints stack usage for functions
in two ways:($re and $dre)

dre breaks sorting mechanism.
0xffffa00011f26f88 sunxi_mux_clk_setup.isra.0 [vmlinux]:Dynamic (0x140)
..
0xffffa00011f27210 sunxi_divs_clk_setup [vmlinux]:      Dynamic (0x1d0)

so we can print it in decimal only.

Also address before function name is changed to function
start address rather than stack consumption address.
Because in next patch, arm has two ways to use stack
which can be clubbed and printed in one function only.

All symbols whose stack by adding(re and dre) is greater than
100, will be printed.

0xffffa00011f2720c0 sunxi_divs_clk_setup [vmlinux]:     464
...
0xffffa00011f26f840 sunxi_mux_clk_setup.isra.0 [vmlinux]:320

Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Gustavo A. R. Silva
859c817501 modpost,fixdep: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Siddharth Gupta
5967577231 scripts: headers_install: Exit with error on config leak
Misuse of CONFIG_* in UAPI headers should result in an error. These config
options can be set in userspace by the user application which includes
these headers to control the APIs and structures being used in a kernel
which supports multiple targets.

Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
bcfefb61cd kconfig: announce removal of 'kvmconfig' and 'xenconfig' shorthands
kvmconfig' is a shorthand for kvm_guest.config to save 7 character typing.

xenconfig' is a shorthand for xen.config to save 1 character typing.

There is nothing more than that.

There are more files in kernel/configs/, so it is not maintainable
to wire-up every config fragment to the Kconfig Makefile. Hence,
we should not do this at all.

These will be removed after Linux 5.10. Meanwhile, the following
warning message will be displayed if they are used.

WARNING: 'make kvmconfig' will be removed after Linux 5.10
         Please use 'make kvm_guest.config' instead.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:02:32 +09:00
Thomas Gleixner
6553896666 vmlinux.lds.h: Create section for protection against instrumentation
Some code pathes, especially the low level entry code, must be protected
against instrumentation for various reasons:

 - Low level entry code can be a fragile beast, especially on x86.

 - With NO_HZ_FULL RCU state needs to be established before using it.

Having a dedicated section for such code allows to validate with tooling
that no unsafe functions are invoked.

Add the .noinstr.text section and the noinstr attribute to mark
functions. noinstr implies notrace. Kprobes will gain a section check
later.

Provide also a set of markers: instrumentation_begin()/end()

These are used to mark code inside a noinstr function which calls
into regular instrumentable text section as safe.

The instrumentation markers are only active when CONFIG_DEBUG_ENTRY is
enabled as the end marker emits a NOP to prevent the compiler from merging
the annotation points. This means the objtool verification requires a
kernel compiled with this option.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134100.075416272@linutronix.de
2020-05-19 15:47:20 +02:00