Commit Graph

331 Commits

Author SHA1 Message Date
Wolfram Sang 6020db504c modpost: explain why we can't use strsep
Mention why we open-code strsep, so it is clear that it is intentional.

Fixes: 736bb11898 ("modpost: remove use of non-standard strsep() in HOSTCC code")
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-07-27 13:38:38 +09:00
H. Nikolaus Schaller 736bb11898 modpost: remove use of non-standard strsep() in HOSTCC code
strsep() is neither standard C nor POSIX and used outside
the kernel code here. Using it here requires that the
build host supports it out of the box which is e.g.
not true for a Darwin build host and using a cross-compiler.
This leads to:

scripts/mod/modpost.c:145:2: warning: implicit declaration of function 'strsep' [-Wimplicit-function-declaration]
  return strsep(stringp, "\n");
  ^

and a segfault when running MODPOST.

See also: https://stackoverflow.com/a/7219504

So let's replace this by strchr() instead of using strsep().
It does not hurt kernel size or speed since this code is run
on the build host.

Fixes: ac5100f543 ("modpost: add read_text_file() and get_line() helpers")
Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-07-07 11:21:00 +09:00
Linus Torvalds cff11abeca Kbuild updates for v5.8
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
 
  - ensure to rebuild all objects when the compiler is upgraded
 
  - exclude system headers from dependency tracking and fixdep processing
 
  - fix potential bit-size mismatch between the kernel and BPF user-mode
    helper
 
  - add the new syntax 'userprogs' to build user-space programs for the
    target architecture (the same arch as the kernel)
 
  - compile user-space sample code under samples/ for the target arch
    instead of the host arch
 
  - make headers_install fail if a CONFIG option is leaked to user-space
 
  - sanitize the output format of scripts/checkstack.pl
 
  - handle ARM 'push' instruction in scripts/checkstack.pl
 
  - error out before modpost if a module name conflict is found
 
  - error out when multiple directories are passed to M= because this
    feature is broken for a long time
 
  - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
 
  - a lot of cleanups of modpost
 
  - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
    second pass of modpost
 
  - do not run the second pass of modpost if nothing in modules is updated
 
  - install modules.builtin(.modinfo) by 'make install' as well as by
    'make modules_install' because it is useful even when CONFIG_MODULES=n
 
  - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
    to allow users to use alternatives such as pigz, pbzip2, etc.
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Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

 - fix potential bit-size mismatch between the kernel and BPF user-mode
   helper

 - add the new syntax 'userprogs' to build user-space programs for the
   target architecture (the same arch as the kernel)

 - compile user-space sample code under samples/ for the target arch
   instead of the host arch

 - make headers_install fail if a CONFIG option is leaked to user-space

 - sanitize the output format of scripts/checkstack.pl

 - handle ARM 'push' instruction in scripts/checkstack.pl

 - error out before modpost if a module name conflict is found

 - error out when multiple directories are passed to M= because this
   feature is broken for a long time

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

 - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
   second pass of modpost

 - do not run the second pass of modpost if nothing in modules is
   updated

 - install modules.builtin(.modinfo) by 'make install' as well as by
   'make modules_install' because it is useful even when
   CONFIG_MODULES=n

 - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
   to allow users to use alternatives such as pigz, pbzip2, etc.

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info->size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod->skip struct member
  modpost: add mod->is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod->is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
2020-06-06 12:00:25 -07:00
Masahiro Yamada 3b09efc4f0 modpost: change elf_info->size to size_t
Align with the mmap / munmap APIs.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada 4de7b62936 modpost: remove is_vmlinux() helper
Now that is_vmlinux() is called only in new_module(), we can inline
the function call.

modname is the basename with '.o' is stripped. No need to compare it
with 'vmlinux.o'.

vmlinux is always located at the current working directory. No need
to strip the directory path.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada a82f794c41 modpost: strip .o from modname before calling new_module()
new_module() conditionally strips the .o because the modname has .o
suffix when it is called from read_symbols(), but no .o when it is
called from read_dump().

It is clearer to strip .o in read_symbols().

I also used flexible-array for mod->name.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada 858b937d28 modpost: set have_vmlinux in new_module()
Set have_vmlinux flag in a single place.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada 0b19d54cae modpost: remove mod->skip struct member
The meaning of 'skip' is obscure since it does not explain
"what to skip".

mod->skip is set when it is vmlinux or the module info came from
a dump file.

So, mod->skip is equivalent to (mod->is_vmlinux || mod->from_dump).

For the check in write_namespace_deps_files(), mod->is_vmlinux is
unneeded because the -d option is not passed in the first pass of
modpost.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada 5a438af9db modpost: add mod->is_vmlinux struct member
is_vmlinux() is called in several places to check whether the current
module is vmlinux or not.

It is faster and clearer to check mod->is_vmlinux flag.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:19 +09:00
Masahiro Yamada 1be5fa6c94 modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
check_exports() is never called for vmlinux because mod->skip is set
for vmlinux.

Hence, check_for_gpl_usage() and check_for_unused() are not called
for vmlinux, either. is_vmlinux() is always false here.

Remove the is_vmlinux() calls, and hard-code the ".ko" suffix.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada 3379576dd6 modpost: remove mod->is_dot_o struct member
Previously, there were two cases where mod->is_dot_o is unset:

[1] the executable 'vmlinux' in the second pass of modpost
[2] modules loaded by read_dump()

I think [1] was intended usage to distinguish 'vmlinux.o' and 'vmlinux'.
Now that modpost does not parse the executable 'vmlinux', this case
does not happen.

[2] is obscure, maybe a bug. Module.symver stores module paths without
extension. So, none of modules loaded by read_dump() has the .o suffix,
and new_module() unsets ->is_dot_o. Anyway, it is not a big deal because
handle_symbol() is not called for the case.

To sum up, all the parsed ELF files are .o files.

mod->is_dot_o is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada 467b82d7ce modpost: remove -s option
The -s option was added by commit 8d8d8289df ("kbuild: do not do
section mismatch checks on vmlinux in 2nd pass").

Now that the second pass does not parse vmlinux, this option is
unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada 75893572d4 modpost: remove get_next_text() and make {grab,release_}file static
get_next_line() is no longer used. Remove.

grab_file() and release_file() are only used in modpost.c. Make them
static.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada 70f30cfe5b modpost: use read_text_file() and get_line() for reading text files
grab_file() mmaps a file, but it is not so efficient here because
get_next_line() copies every line to the temporary buffer anyway.

read_text_file() and get_line() are simpler. get_line() exploits the
library function strchr().

Going forward, the missing *.symvers or *.cmd is a fatal error.
This should not happen because scripts/Makefile.modpost guards the
-i option files with $(wildcard $(input-symdump)).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada ac5100f543 modpost: add read_text_file() and get_line() helpers
modpost uses grab_file() to open a file, but it is not suitable for
a text file because the mmap'ed file is not terminated by null byte.
Actually, I see some issues for the use of grab_file().

The new helper, read_text_file() loads the whole file content into a
malloc'ed buffer, and appends a null byte. Then, get_line() reads
each line.

To handle text files, I intend to replace as follows:

  grab_file()    -> read_text_file()
  get_new_line() -> get_line()

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada 4ddea2f8e8 modpost: do not call get_modinfo() for vmlinux(.o)
The three calls of get_modinfo() ("license", "import_ns", "version")
always return NULL for vmlinux(.o) because the built-in module info is
prefixed with __MODULE_INFO_PREFIX.

It is harmless to call get_modinfo(), but there is no point to search
for what apparently does not exist.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada f693153519 modpost: drop RCS/CVS $Revision handling in MODULE_VERSION()
As far as I understood, this code gets rid of '$Revision$' or '$Revision:'
of CVS, RCS or whatever in MODULE_VERSION() tags.

Remove the primeval code.

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 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
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 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
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 7649773293 ("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
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
Leon Romanovsky 51161bfc66 kernel/module: Hide vermagic header file from general use
VERMAGIC* definitions are not supposed to be used by the drivers,
see this [1] bug report, so introduce special define to guard inclusion
of this header file and define it in kernel/modules.h and in internal
script that generates *.mod.c files.

In-tree module build:
➜  kernel git:(vermagic) ✗ make clean
➜  kernel git:(vermagic) ✗ make M=drivers/infiniband/hw/mlx5
➜  kernel git:(vermagic) ✗ modinfo drivers/infiniband/hw/mlx5/mlx5_ib.ko
filename:	/images/leonro/src/kernel/drivers/infiniband/hw/mlx5/mlx5_ib.ko
<...>
vermagic:       5.6.0+ SMP mod_unload modversions

Out-of-tree module build:
➜  mlx5 make -C /images/leonro/src/kernel clean M=/tmp/mlx5
➜  mlx5 make -C /images/leonro/src/kernel M=/tmp/mlx5
➜  mlx5 modinfo /tmp/mlx5/mlx5_ib.ko
filename:       /tmp/mlx5/mlx5_ib.ko
<...>
vermagic:       5.6.0+ SMP mod_unload modversions

[1] https://lore.kernel.org/lkml/20200411155623.GA22175@zn.tnic
Reported-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Jessica Yu <jeyu@kernel.org>
Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-21 13:27:37 -07:00
Linus Torvalds 5b67fbfc32 Kbuild updates for v5.7
[Build system]
 
  - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define
    a fixed set of export symbols for Generic Kernel Image (GKI)
 
  - allow to run 'make dt_binding_check' without .config
 
  - use full schema for checking DT examples in *.yaml files
 
  - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
    sense because we know the produced modules are never loadable
 
  - Remove unused 'AS' variable
 
 [Kconfig]
 
  - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig files
 
  - relax the 'imply' behavior so that symbols implied by y can become m
 
  - make 'imply' obey 'depends on' in order to make 'imply' really weak
 
 [Misc]
 
  - add documentation on building the kernel with Clang/LLVM
 
  - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()
 
  - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n
 
  - various script and Makefile cleanups
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Merge tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "Build system:

   - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define a
     fixed set of export symbols for Generic Kernel Image (GKI)

   - allow to run 'make dt_binding_check' without .config

   - use full schema for checking DT examples in *.yaml files

   - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
     sense because we know the produced modules are never loadable

   - Remove unused 'AS' variable

  Kconfig:

   - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
     files

   - relax the 'imply' behavior so that symbols implied by 'y' can
     become 'm'

   - make 'imply' obey 'depends on' in order to make 'imply' really weak

  Misc:

   - add documentation on building the kernel with Clang/LLVM

   - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()

   - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n

   - various script and Makefile cleanups"

* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  Makefile: Update kselftest help information
  kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
  kbuild: add outputmakefile to no-dot-config-targets
  kbuild: remove AS variable
  net: wan: wanxl: refactor the firmware rebuild rule
  net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
  net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
  kbuild: add comment about grouped target
  kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
  kconfig: remove unused variable in qconf.cc
  sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
  kbuild: refactor Makefile.dtbinst more
  kbuild: compute the dtbs_install destination more simply
  Makefile: disallow data races on gcc-10 as well
  kconfig: make 'imply' obey the direct dependency
  kconfig: allow symbols implied by y to become m
  net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
  modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
  modpost: rework and consolidate logging interface
  kbuild: allow to run dt_binding_check without kernel configuration
  ...
2020-03-31 16:03:39 -07:00
Linus Torvalds dbb381b619 timekeeping and timer updates:
Core:
 
   - Consolidation of the vDSO build infrastructure to address the
     difficulties of cross-builds for ARM64 compat vDSO libraries by
     restricting the exposure of header content to the vDSO build.
 
     This is achieved by splitting out header content into separate
     headers. which contain only the minimaly required information which is
     necessary to build the vDSO. These new headers are included from the
     kernel headers and the vDSO specific files.
 
   - Enhancements to the generic vDSO library allowing more fine grained
     control over the compiled in code, further reducing architecture
     specific storage and preparing for adopting the generic library by PPC.
 
   - Cleanup and consolidation of the exit related code in posix CPU timers.
 
   - Small cleanups and enhancements here and there
 
  Drivers:
 
   - The obligatory new drivers: Ingenic JZ47xx and X1000 TCU support
 
   - Correct the clock rate of PIT64b global clock
 
   - setup_irq() cleanup
 
   - Preparation for PWM and suspend support for the TI DM timer
 
   - Expand the fttmr010 driver to support ast2600 systems
 
   - The usual small fixes, enhancements and cleanups all over the place
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Merge tag 'timers-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timekeeping and timer updates from Thomas Gleixner:
 "Core:

   - Consolidation of the vDSO build infrastructure to address the
     difficulties of cross-builds for ARM64 compat vDSO libraries by
     restricting the exposure of header content to the vDSO build.

     This is achieved by splitting out header content into separate
     headers. which contain only the minimaly required information which
     is necessary to build the vDSO. These new headers are included from
     the kernel headers and the vDSO specific files.

   - Enhancements to the generic vDSO library allowing more fine grained
     control over the compiled in code, further reducing architecture
     specific storage and preparing for adopting the generic library by
     PPC.

   - Cleanup and consolidation of the exit related code in posix CPU
     timers.

   - Small cleanups and enhancements here and there

  Drivers:

   - The obligatory new drivers: Ingenic JZ47xx and X1000 TCU support

   - Correct the clock rate of PIT64b global clock

   - setup_irq() cleanup

   - Preparation for PWM and suspend support for the TI DM timer

   - Expand the fttmr010 driver to support ast2600 systems

   - The usual small fixes, enhancements and cleanups all over the
     place"

* tag 'timers-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits)
  Revert "clocksource/drivers/timer-probe: Avoid creating dead devices"
  vdso: Fix clocksource.h macro detection
  um: Fix header inclusion
  arm64: vdso32: Enable Clang Compilation
  lib/vdso: Enable common headers
  arm: vdso: Enable arm to use common headers
  x86/vdso: Enable x86 to use common headers
  mips: vdso: Enable mips to use common headers
  arm64: vdso32: Include common headers in the vdso library
  arm64: vdso: Include common headers in the vdso library
  arm64: Introduce asm/vdso/processor.h
  arm64: vdso32: Code clean up
  linux/elfnote.h: Replace elf.h with UAPI equivalent
  scripts: Fix the inclusion order in modpost
  common: Introduce processor.h
  linux/ktime.h: Extract common header for vDSO
  linux/jiffies.h: Extract common header for vDSO
  linux/time64.h: Extract common header for vDSO
  linux/time32.h: Extract common header for vDSO
  linux/time.h: Extract common header for vDSO
  ...
2020-03-30 18:51:47 -07:00
Vincenzo Frascino f58dd03b11 scripts: Fix the inclusion order in modpost
In the process of creating the source file of a module modpost injects a
set of includes that are not required if the compilation unit is
statically built into the kernel.

The order of inclusion of the headers can cause redefinition problems
(e.g.):

   In file included from include/linux/elf.h:5:0,
                    from include/linux/module.h:18,
                    from crypto/arc4.mod.c:2:
    #define ELF_OSABI  ELFOSABI_LINUX

   In file included from include/linux/elfnote.h:62:0,
                    from include/linux/build-salt.h:4,
                    from crypto/arc4.mod.c:1:
   include/uapi/linux/elf.h:363:0: note: this is the location of
   the previous definition
    #define ELF_OSABI ELFOSABI_NONE

The issue was exposed during the development of the series [1].

[1] https://lore.kernel.org/lkml/20200306133242.26279-1-vincenzo.frascino@arm.com/

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Link: https://lkml.kernel.org/r/20200320145351.32292-17-vincenzo.frascino@arm.com
2020-03-21 15:24:00 +01:00
Xiao Yang 4b8a5cfb5f modpost: Get proper section index by get_secindex() instead of st_shndx
(uint16_t) st_shndx is limited to 65535(i.e. SHN_XINDEX) so sym_get_data() gets
wrong section index by st_shndx if requested symbol contains extended section
index that is more than 65535.  In this case, we need to get proper section index
by .symtab_shndx section.

Module.symvers generated by building kernel with "-ffunction-sections -fdata-sections"
shows the issue.

Fixes: 56067812d5 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Fixes: e84f9fbbec ("modpost: refactor namespace_from_kstrtabns() to not hard-code section name")
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-19 01:44:25 +09:00
Jessica Yu 5190044c29 modpost: move the namespace field in Module.symvers last
In order to preserve backwards compatability with kmod tools, we have to
move the namespace field in Module.symvers last, as the depmod -e -E
option looks at the first three fields in Module.symvers to check symbol
versions (and it's expected they stay in the original order of crc,
symbol, module).

In addition, update an ancient comment above read_dump() in modpost that
suggested that the export type field in Module.symvers was optional. I
suspect that there were historical reasons behind that comment that are
no longer accurate. We have been unconditionally printing the export
type since 2.6.18 (commit bd5cbcedf4), which is over a decade ago now.

Fix up read_dump() to treat each field as non-optional. I suspect the
original read_dump() code treated the export field as optional in order
to support pre <= 2.6.18 Module.symvers (which did not have the export
type field). Note that although symbol namespaces are optional, the
field will not be omitted from Module.symvers if a symbol does not have
a namespace. In this case, the field will simply be empty and the next
delimiter or end of line will follow.

Cc: stable@vger.kernel.org
Fixes: cb9b55d21f ("modpost: add support for symbol namespaces")
Tested-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-17 08:59:03 +09:00
Jessica Yu 54b7784769 modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
Currently when CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n, modpost
only warns when a module is missing namespace imports. Under this
configuration, such a module cannot be loaded into the kernel anyway, as
the module loader would reject it. We might as well return a build
error when a module is missing namespace imports under
CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n, so that the build
warning does not go ignored/unnoticed.

Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-13 10:04:36 +09:00
Jessica Yu 93c95e526a modpost: rework and consolidate logging interface
Rework modpost's logging interface by consolidating merror(), warn(), and
fatal() to use a single function, modpost_log(). Introduce different
logging levels (WARN, ERROR, FATAL) as well. The purpose of this cleanup is
to reduce code duplication when deciding whether or not to warn or error
out based on a condition.

Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-13 10:04:36 +09:00
Masahiro Yamada 5370d4acc5 modpost: assume STT_SPARC_REGISTER is defined
Commit 8d5290149e ("[SPARC]: Deal with glibc changing macro names in
modpost.c") was more than 14 years ago. STT_SPARC_REGISTER is hopefully
defined in elf.h of recent C libraries.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
2020-01-16 00:26:22 +09:00
Masahiro Yamada 7ef9ab3b32 modpost: respect the previous export when 'exported twice' is warned
When 'exported twice' is warned, let sym_add_exported() return without
updating the symbol info. This respects the previous export, which is
ordered first in modules.order

This simplifies the code too.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-23 15:46:42 +09:00
Masahiro Yamada e4b26c9f75 modpost: do not set ->preloaded for symbols from Module.symvers
Now that there is no overwrap between symbols from ELF files and
ones from Module.symvers.

So, the 'exported twice' warning should be reported irrespective
of where the symbol in question came from.

The exceptional case is external module; in some cases, we build
an external module to provide a different version/variant of the
corresponding in-kernel module, overriding the same set of exported
symbols.

You can see this use-case in upstream; tools/testing/nvdimm/libnvdimm.ko
replaces drivers/nvdimm/libnvdimm.ko in order to link it against mocked
version of core kernel symbols.

So, let's relax the 'exported twice' warning when building external
modules. The multiple export from external modules is warned only
when the previous one is from vmlinux or itself.

With this refactoring, the ugly preloading goes away.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-23 15:46:42 +09:00
Masahiro Yamada 1743694eb2 modpost: stop symbol preloading for modversion CRC
It is complicated to add mocked-up symbols for pre-handling CRC.
Handle CRC after all the export symbols in the relevant module
are registered.

Call handle_modversion() after the handle_symbol() iteration.

In some cases, I see atand-alone __crc_* without __ksymtab_*.
For example, ARCH=arm allyesconfig produces __crc_ccitt_veneer and
__crc_itu_t_veneer. I guess they come from crc_ccitt, crc_itu_t,
respectively. Since __*_veneer are auto-generated symbols, just
ignore them.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-23 15:46:38 +09:00
Masahiro Yamada 9bd2a099d7 modpost: rename handle_modversions() to handle_symbol()
This function handles not only modversions, but also unresolved
symbols, export symbols, etc.

Rename it to a more proper function name.

While I was here, I also added the 'const' qualifier to *sym.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-23 12:44:24 +09:00
Masahiro Yamada e84f9fbbec modpost: refactor namespace_from_kstrtabns() to not hard-code section name
Currently, namespace_from_kstrtabns() relies on the fact that
namespace strings are recorded in the __ksymtab_strings section.
Actually, it is coded in include/linux/export.h, but modpost does
not need to hard-code the section name.

Elf_Sym::st_shndx holds the index of the relevant section. Using it is
a more portable way to get the namespace string.

Make namespace_from_kstrtabns() simply call sym_get_data(), and delete
the info->ksymtab_strings .

While I was here, I added more 'const' qualifiers to pointers.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-23 12:44:24 +09:00
Masahiro Yamada afa0459daa modpost: add a helper to get data pointed by a symbol
When CONFIG_MODULE_REL_CRCS is enabled, the value of __crc_* is not
an absolute value, but the address to the CRC data embedded in the
.rodata section.

Getting the data pointed by the symbol value is somewhat complex.
Split it out into a new helper, sym_get_data().

I will reuse it to refactor namespace_from_kstrtabns() in the next
commit.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-23 12:44:24 +09:00
Masahiro Yamada 76b54cf033 modpost: remove unneeded local variable in contains_namespace()
The local variable, ns_entry, is unneeded.

While I was here, I also cleaned up the comparison with NULL or 0.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
2019-11-11 20:10:01 +09:00
Masahiro Yamada bbc55bded4 modpost: dump missing namespaces into a single modules.nsdeps file
The modpost, with the -d option given, generates per-module .ns_deps
files.

Kbuild generates per-module .mod files to carry module information.
This is convenient because Make handles multiple jobs in parallel
when the -j option is given.

On the other hand, the modpost always runs as a single thread.
I do not see a strong reason to produce separate .ns_deps files.

This commit changes the modpost to generate just one file,
modules.nsdeps, each line of which has the following format:

  <module_name>: <list of missing namespaces>

Please note it contains *missing* namespaces instead of required ones.
So, modules.nsdeps is empty if the namespace dependency is all good.

This will work more efficiently because spatch will no longer process
already imported namespaces. I removed the '(if needed)' from the
nsdeps log since spatch is invoked only when needed.

This also solves the stale .ns_deps problem reported by Jessica Yu:

  https://lkml.org/lkml/2019/10/28/467

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Reviewed-by: Matthias Maennich <maennich@google.com>
Tested-by: Matthias Maennich <maennich@google.com>
2019-11-11 20:10:01 +09:00
Masahiro Yamada 0241ea8cae modpost: free ns_deps_buf.p after writing ns_deps files
buf_write() allocates memory. Free it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-11 20:10:01 +09:00
Masahiro Yamada bff9c62b5d modpost: do not invoke extra modpost for nsdeps
'make nsdeps' invokes the modpost three times at most; before linking
vmlinux, before building modules, and finally for generating .ns_deps
files. Running the modpost again and again is not efficient.

The last two can be unified. When the -d option is given, the modpost
still does the usual job, and in addition, generates .ns_deps files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
2019-11-11 20:10:01 +09:00
Masahiro Yamada 39808e451f kbuild: do not read $(KBUILD_EXTMOD)/Module.symvers
Since commit 040fcc819a ("kbuild: improved modversioning support for
external modules"), the external module build reads Module.symvers in
the directory of the module itself, then dumps symbols back into it.
It accumulates stale symbols in the file when you build an external
module incrementally.

The idea behind it was, as the commit log explained, you can copy
Modules.symvers from one module to another when you need to pass symbol
information between two modules. However, the manual copy of the file
sounds questionable to me, and containing stale symbols is a downside.

Some time later, commit 0d96fb20b7 ("kbuild: Add new Kbuild variable
KBUILD_EXTRA_SYMBOLS") introduced a saner approach.

So, this commit removes the former one. Going forward, the external
module build dumps symbols into Module.symvers to be carried via
KBUILD_EXTRA_SYMBOLS, but never reads it automatically.

With the -I option removed, there is no one to set the external_module
flag unless KBUILD_EXTRA_SYMBOLS is passed. Now the -i option does it
instead.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-11 20:07:03 +09:00
Matthias Maennich 6992320843 symbol namespaces: revert to previous __ksymtab name scheme
The introduction of Symbol Namespaces changed the naming schema of the
__ksymtab entries from __kysmtab__symbol to __ksymtab_NAMESPACE.symbol.

That caused some breakages in tools that depend on the name layout in
either the binaries(vmlinux,*.ko) or in System.map. E.g. kmod's depmod
would not be able to read System.map without a patch to support symbol
namespaces. A warning reported by depmod for namespaced symbols would
look like

  depmod: WARNING: [...]/uas.ko needs unknown symbol usb_stor_adjust_quirks

In order to address this issue, revert to the original naming scheme and
rather read the __kstrtabns_<symbol> entries and their corresponding
values from __ksymtab_strings to update the namespace values for
symbols. After having read all symbols and handled them in
handle_modversions(), the symbols are created. In a second pass, read
the __kstrtabns_ entries and update the namespaces accordingly.

Fixes: 8651ec01da ("module: add support for symbol namespaces.")
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
2019-10-18 15:32:52 +02:00