Commit Graph

7028 Commits

Author SHA1 Message Date
Sami Tolvanen
19a4cb1c4e Makefile.extrawarn: Move -Wcast-function-type-strict to W=1
commit 2120635108 upstream.

We enable -Wcast-function-type globally in the kernel to warn about
mismatching types in function pointer casts. Compilers currently
warn only about ABI incompability with this flag, but Clang 16 will
enable a stricter version of the check by default that checks for an
exact type match. This will be very noisy in the kernel, so disable
-Wcast-function-type-strict without W=1 until the new warnings have
been addressed.

Cc: stable@vger.kernel.org
Link: https://reviews.llvm.org/D134831
Link: https://github.com/ClangBuiltLinux/linux/issues/1724
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220930203310.4010564-1-samitolvanen@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-12 09:51:23 +02:00
Nick Desaulniers
27d5563e8f Makefile.debug: re-enable debug info for .S files
[ Upstream commit 32ef9e5054 ]

Alexey reported that the fraction of unknown filename instances in
kallsyms grew from ~0.3% to ~10% recently; Bill and Greg tracked it down
to assembler defined symbols, which regressed as a result of:

commit b8a9092330 ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")

In that commit, I allude to restoring debug info for assembler defined
symbols in a follow up patch, but it seems I forgot to do so in

commit a66049e2cf ("Kbuild: make DWARF version a choice")

Link: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=31bf18645d98b4d3d7357353be840e320649a67d
Fixes: b8a9092330 ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")
Reported-by: Alexey Alexandrov <aalexand@google.com>
Reported-by: Bill Wendling <morbo@google.com>
Reported-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:32:27 +02:00
Nick Desaulniers
6ba8627f72 Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT
[ Upstream commit 61f2b7c749 ]

Dmitrii, Fangrui, and Mashahiro note:

  Before GCC 11 and Clang 12 -gsplit-dwarf implicitly uses -g2.

Fix CONFIG_DEBUG_INFO_SPLIT for gcc-11+ & clang-12+ which now need -g
specified in order for -gsplit-dwarf to work at all.

-gsplit-dwarf has been mutually exclusive with -g since support for
CONFIG_DEBUG_INFO_SPLIT was introduced in
commit 866ced950b ("kbuild: Support split debug info v4")
I don't think it ever needed to be.

Link: https://lore.kernel.org/lkml/20220815013317.26121-1-dmitrii.bundin.a@gmail.com/
Link: https://lore.kernel.org/lkml/CAK7LNARPAmsJD5XKAw7m_X2g7Fi-CAAsWDQiP7+ANBjkg7R7ng@mail.gmail.com/
Link: https://reviews.llvm.org/D80391
Cc: Andi Kleen <ak@linux.intel.com>
Reported-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Reported-by: Fangrui Song <maskray@google.com>
Reported-by: Masahiro Yamada <masahiroy@kernel.org>
Suggested-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Stable-dep-of: 32ef9e5054 ("Makefile.debug: re-enable debug info for .S files")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:32:27 +02:00
Ondrej Mosnacek
d98703d4ce kbuild: dummy-tools: avoid tmpdir leak in dummy gcc
commit aac289653f upstream

When passed -print-file-name=plugin, the dummy gcc script creates a
temporary directory that is never cleaned up. To avoid cluttering
$TMPDIR, instead use a static directory included in the source tree.

Fixes: 76426e2388 ("kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/9996285f-5a50-e56a-eb1c-645598381a20@kernel.org
[ just the plugin-version.h portion as it failed to apply previously - gregkh ]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-29 11:07:58 +02:00
Helge Deller
62c8639072 modules: Ensure natural alignment for .altinstructions and __bug_table sections
[ Upstream commit 87c482bdfa ]

In the kernel image vmlinux.lds.S linker scripts the .altinstructions
and __bug_table sections are 4- or 8-byte aligned because they hold 32-
and/or 64-bit values.

Most architectures use altinstructions and BUG() or WARN() in modules as
well, but in the module linker script (module.lds.S) those sections are
currently missing. As consequence the linker will store their content
byte-aligned by default, which then can lead to unnecessary unaligned
memory accesses by the CPU when those tables are processed at runtime.

Usually unaligned memory accesses are unnoticed, because either the
hardware (as on x86 CPUs) or in-kernel exception handlers (e.g. on
parisc or sparc) emulate and fix them up at runtime. Nevertheless, such
unaligned accesses introduce a performance penalty and can even crash
the kernel if there is a bug in the unalignment exception handlers
(which happened once to me on the parisc architecture and which is why I
noticed that issue at all).

This patch fixes a non-critical issue and might be backported at any time.
It's trivial and shouldn't introduce any regression because it simply
tells the linker to use a different (8-byte alignment) for those
sections by default.

Signed-off-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/all/Yr8%2Fgr8e8I7tVX4d@p100/
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:45:49 +02:00
Andrew Donnellan
5ba9bafa2c gcc-plugins: Undefine LATENT_ENTROPY_PLUGIN when plugin disabled for a file
commit 012e8d2034 upstream.

Commit 36d4b36b69 ("lib/nodemask: inline next_node_in() and
node_random()") refactored some code by moving node_random() from
lib/nodemask.c to include/linux/nodemask.h, thus requiring nodemask.h to
include random.h, which conditionally defines add_latent_entropy()
depending on whether the macro LATENT_ENTROPY_PLUGIN is defined.

This broke the build on powerpc, where nodemask.h is indirectly included
in arch/powerpc/kernel/prom_init.c, part of the early boot machinery that
is excluded from the latent entropy plugin using
DISABLE_LATENT_ENTROPY_PLUGIN. It turns out that while we add a gcc flag
to disable the actual plugin, we don't undefine LATENT_ENTROPY_PLUGIN.

This leads to the following:

    CC      arch/powerpc/kernel/prom_init.o
  In file included from ./include/linux/nodemask.h:97,
                   from ./include/linux/mmzone.h:17,
                   from ./include/linux/gfp.h:7,
                   from ./include/linux/xarray.h:15,
                   from ./include/linux/radix-tree.h:21,
                   from ./include/linux/idr.h:15,
                   from ./include/linux/kernfs.h:12,
                   from ./include/linux/sysfs.h:16,
                   from ./include/linux/kobject.h:20,
                   from ./include/linux/pci.h:35,
                   from arch/powerpc/kernel/prom_init.c:24:
  ./include/linux/random.h: In function 'add_latent_entropy':
  ./include/linux/random.h:25:46: error: 'latent_entropy' undeclared (first use in this function); did you mean 'add_latent_entropy'?
     25 |         add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy));
        |                                              ^~~~~~~~~~~~~~
        |                                              add_latent_entropy
  ./include/linux/random.h:25:46: note: each undeclared identifier is reported only once for each function it appears in
  make[2]: *** [scripts/Makefile.build:249: arch/powerpc/kernel/prom_init.o] Fehler 1
  make[1]: *** [scripts/Makefile.build:465: arch/powerpc/kernel] Fehler 2
  make: *** [Makefile:1855: arch/powerpc] Error 2

Change the DISABLE_LATENT_ENTROPY_PLUGIN flags to undefine
LATENT_ENTROPY_PLUGIN for files where the plugin is disabled.

Cc: Yury Norov <yury.norov@gmail.com>
Fixes: 38addce8b6 ("gcc-plugins: Add latent_entropy plugin")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216367
Link: https://lore.kernel.org/linuxppc-dev/alpine.DEB.2.22.394.2208152006320.289321@ramsan.of.borg/
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220816051720.44108-1-ajd@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:45:37 +02:00
Masahiro Yamada
5fc790e349 modpost: fix module versioning when a symbol lacks valid CRC
commit 5b8a9a8fd1 upstream.

Since commit 7b4537199a ("kbuild: link symbol CRCs at final link,
removing CONFIG_MODULE_REL_CRCS"), module versioning is broken on
some architectures. Loading a module fails with "disagrees about
version of symbol module_layout".

On such architectures (e.g. ARCH=sparc build with sparc64_defconfig),
modpost shows a warning, like follows:

  WARNING: modpost: EXPORT symbol "_mcount" [vmlinux] version generation failed, symbol will not be versioned.
  Is "_mcount" prototyped in <asm/asm-prototypes.h>?

Previously, it was a harmless warning (CRC check was just skipped),
but now wrong CRCs are used for comparison because invalid CRCs are
just skipped.

  $ sparc64-linux-gnu-nm -n vmlinux
    [snip]
  0000000000c2cea0 r __ksymtab__kstrtol
  0000000000c2ceb8 r __ksymtab__kstrtoul
  0000000000c2ced0 r __ksymtab__local_bh_enable
  0000000000c2cee8 r __ksymtab__mcount
  0000000000c2cf00 r __ksymtab__printk
  0000000000c2cf18 r __ksymtab__raw_read_lock
  0000000000c2cf30 r __ksymtab__raw_read_lock_bh
    [snip]
  0000000000c53b34 D __crc__kstrtol
  0000000000c53b38 D __crc__kstrtoul
  0000000000c53b3c D __crc__local_bh_enable
  0000000000c53b40 D __crc__printk
  0000000000c53b44 D __crc__raw_read_lock
  0000000000c53b48 D __crc__raw_read_lock_bh

Please notice __crc__mcount is missing here.

When the module subsystem looks up a CRC that comes after, it results
in reading out a wrong address. For example, when __crc__printk is
needed, the module subsystem reads 0xc53b44 instead of 0xc53b40.

All CRC entries must be output for correct index accessing. Invalid
CRCs will be unused, but are needed to keep the one-to-one mapping
between __ksymtab_* and __crc_*.

The best is to fix all modpost warnings, but several warnings are still
remaining on less popular architectures.

Fixes: 7b4537199a ("kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS")
Reported-by: matoro <matoro_mailinglist_kernel@matoro.tk>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: matoro <matoro_mailinglist_kernel@matoro.tk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:45:35 +02:00
Ondrej Mosnacek
d7e676b7dc kbuild: dummy-tools: avoid tmpdir leak in dummy gcc
commit aac289653f upstream.

When passed -print-file-name=plugin, the dummy gcc script creates a
temporary directory that is never cleaned up. To avoid cluttering
$TMPDIR, instead use a static directory included in the source tree.

Fixes: 76426e2388 ("kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:45:24 +02:00
Josh Poimboeuf
33d3905b22 scripts/faddr2line: Fix vmlinux detection on arm64
[ Upstream commit b6a5068854 ]

Since commit dcea997bee ("faddr2line: Fix overlapping text section
failures, the sequel"), faddr2line is completely broken on arm64.

For some reason, on arm64, the vmlinux ELF object file type is ET_DYN
rather than ET_EXEC.  Check for both when determining whether the object
is vmlinux.

Modules and vmlinux.o have type ET_REL on all arches.

Fixes: dcea997bee ("faddr2line: Fix overlapping text section failures, the sequel")
Reported-by: John Garry <john.garry@huawei.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/dad1999737471b06d6188ce4cdb11329aa41682c.1658426357.git.jpoimboe@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 15:16:01 +02:00
Antonio Borneo
e5cee61879 scripts/gdb: fix 'lx-dmesg' on 32 bits arch
[ Upstream commit e3c8d33e0d ]

The type atomic_long_t can have size 4 or 8 bytes, depending on
CONFIG_64BIT; it's only content, the field 'counter', is either an
int or a s64 value.

Current code incorrectly uses the fixed size utils.read_u64() to
read the field 'counter' inside atomic_long_t.

On 32 bits architectures reading the last element 'tail_id' of the
struct prb_desc_ring:
	struct prb_desc_ring {
		...
		atomic_long_t tail_id;
	};
causes the utils.read_u64() to access outside the boundary of the
struct and the gdb command 'lx-dmesg' exits with error:
	Python Exception <class 'IndexError'>: index out of range
	Error occurred in Python: index out of range

Query the really used atomic_long_t counter type size.

Link: https://lore.kernel.org/r/20220617143758.137307-1-antonio.borneo@foss.st.com
Fixes: e60768311a ("scripts/gdb: update for lockless printk ringbuffer")
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
[pmladek@suse.com: Query the really used atomic_long_t counter type size]
Tested-by: Antonio Borneo <antonio.borneo@foss.st.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220719122831.19890-1-pmladek@suse.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 15:15:36 +02:00
Khalid Masum
23a67619bc scripts/gdb: Fix gdb 'lx-symbols' command
Currently the command 'lx-symbols' in gdb exits with the error`Function
"do_init_module" not defined in "kernel/module.c"`. This occurs because
the file kernel/module.c was moved to kernel/module/main.c.

Fix this breakage by changing the path to "kernel/module/main.c" in
LoadModuleBreakpoint.

Signed-off-by: Khalid Masum <khalid.masum.92@gmail.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Fixes: cfc1d27789 ("module: Move all into module/")
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-07-21 10:40:55 -07:00
Linus Torvalds
ce114c8668 Merge tag 'x86_bugs_retbleed' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 retbleed fixes from Borislav Petkov:
 "Just when you thought that all the speculation bugs were addressed and
  solved and the nightmare is complete, here's the next one: speculating
  after RET instructions and leaking privileged information using the
  now pretty much classical covert channels.

  It is called RETBleed and the mitigation effort and controlling
  functionality has been modelled similar to what already existing
  mitigations provide"

* tag 'x86_bugs_retbleed' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  x86/speculation: Disable RRSBA behavior
  x86/kexec: Disable RET on kexec
  x86/bugs: Do not enable IBPB-on-entry when IBPB is not supported
  x86/entry: Move PUSH_AND_CLEAR_REGS() back into error_entry
  x86/bugs: Add Cannon lake to RETBleed affected CPU list
  x86/retbleed: Add fine grained Kconfig knobs
  x86/cpu/amd: Enumerate BTC_NO
  x86/common: Stamp out the stepping madness
  KVM: VMX: Prevent RSB underflow before vmenter
  x86/speculation: Fill RSB on vmexit for IBRS
  KVM: VMX: Fix IBRS handling after vmexit
  KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS
  KVM: VMX: Convert launched argument to flags
  KVM: VMX: Flatten __vmx_vcpu_run()
  objtool: Re-add UNWIND_HINT_{SAVE_RESTORE}
  x86/speculation: Remove x86_spec_ctrl_mask
  x86/speculation: Use cached host SPEC_CTRL value for guest entry/exit
  x86/speculation: Fix SPEC_CTRL write on SMT state change
  x86/speculation: Fix firmware entry SPEC_CTRL handling
  x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n
  ...
2022-07-11 18:15:25 -07:00
Masahiro Yamada
f5a4618587 kbuild: remove unused cmd_none in scripts/Makefile.modinst
Commit 65ce9c3832 ("kbuild: move module strip/compression code into
scripts/Makefile.modinst") added this unused code.

Perhaps, I thought cmd_none was useful for CONFIG_MODULE_COMPRESS_NONE,
but I did not use it after all.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-07-10 21:25:15 +09:00
Peter Zijlstra
f43b9876e8 x86/retbleed: Add fine grained Kconfig knobs
Do fine-grained Kconfig for all the various retbleed parts.

NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-29 17:43:41 +02:00
John Hubbard
a4ab14e1d8 gen_compile_commands: handle multiple lines per .mod file
scripts/clang-tools/gen_compile_commands.py incorrectly assumes that
each .mod file only contains one line. That assumption was correct when
the script was originally created, but commit 9413e76405 ("kbuild:
split the second line of *.mod into *.usyms") changed the .mod file
format so that there is one entry per line, and potentially many lines.

The problem can be reproduced by using Kbuild to generate
compile_commands.json, like this:

    make CC=clang compile_commands.json

In many cases, the problem might be overlooked because many subsystems
only have one line anyway. However, in some subsystems (Nouveau, with
762 entries, is a notable example) it results in skipping most of the
subsystem.

Fix this by fully processing each .mod file.

Fixes: 9413e76405 ("kbuild: split the second line of *.mod into *.usyms")
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-29 11:43:13 +09:00
Peter Zijlstra
a09a6e2399 objtool: Add entry UNRET validation
Since entry asm is tricky, add a validation pass that ensures the
retbleed mitigation has been done before the first actual RET
instruction.

Entry points are those that either have UNWIND_HINT_ENTRY, which acts
as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or
those that have UWIND_HINT_IRET_REGS at +0.

This is basically a variant of validate_branch() that is
intra-function and it will simply follow all branches from marked
entry points and ensures that all paths lead to ANNOTATE_UNRET_END.

If a path hits RET or an indirection the path is a fail and will be
reported.

There are 3 ANNOTATE_UNRET_END instances:

 - UNTRAIN_RET itself
 - exception from-kernel; this path doesn't need UNTRAIN_RET
 - all early exceptions; these also don't need UNTRAIN_RET

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27 10:34:00 +02:00
Sami Tolvanen
ff13976676 kbuild: Ignore __this_module in gen_autoksyms.sh
Module object files can contain an undefined reference to __this_module,
which isn't resolved until we link the final .ko. The kernel doesn't
export this symbol, so ignore it in gen_autoksyms.sh.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Steve Muckle <smuckle@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Ramji Jiyani <ramjiyani@google.com>
2022-06-26 06:15:05 +09:00
Masahiro Yamada
28438794ab modpost: fix section mismatch check for exported init/exit sections
Since commit f02e8a6596 ("module: Sort exported symbols"),
EXPORT_SYMBOL* is placed in the individual section ___ksymtab(_gpl)+<sym>
(3 leading underscores instead of 2).

Since then, modpost cannot detect the bad combination of EXPORT_SYMBOL
and __init/__exit.

Fix the .fromsec field.

Fixes: f02e8a6596 ("module: Sort exported symbols")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-06-20 08:18:03 +09:00
Linus Torvalds
5d770f11a1 Merge tag 'objtool-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull build tooling updates from Thomas Gleixner:

 - Remove obsolete CONFIG_X86_SMAP reference from objtool

 - Fix overlapping text section failures in faddr2line for real

 - Remove OBJECT_FILES_NON_STANDARD usage from x86 ftrace and replace it
   with finegrained annotations so objtool can validate that code
   correctly.

* tag 'objtool-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ftrace: Remove OBJECT_FILES_NON_STANDARD usage
  faddr2line: Fix overlapping text section failures, the sequel
  objtool: Fix obsolete reference to CONFIG_X86_SMAP
2022-06-19 09:54:16 -05:00
Linus Torvalds
e3b8e2de19 Merge tag 'kbuild-fixes-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:

 - Make the *.mod build rule portable for POSIX awk

 - Fix regression of 'make nsdeps'

 - Make scripts/check-local-export working for older bash versions

 - Fix scripts/gdb to extract the .config data from vmlinux

* tag 'kbuild-fixes-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  scripts/gdb: change kernel config dumping method
  scripts/check-local-export: avoid 'wait $!' for process substitution
  scripts/nsdeps: adjust to the format change of *.mod files
  kbuild: avoid regex RS for POSIX awk
2022-06-12 11:10:07 -07:00
Kuan-Ying Lee
1f7a6cf6b0 scripts/gdb: change kernel config dumping method
MAGIC_START("IKCFG_ST") and MAGIC_END("IKCFG_ED") are moved out
from the kernel_config_data variable.

Thus, we parse kernel_config_data directly instead of considering
offset of MAGIC_START and MAGIC_END.

Fixes: 13610aa908 ("kernel/configs: use .incbin directive to embed config_data.gz")
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-11 18:31:53 +09:00
Masahiro Yamada
da4288b95b scripts/check-local-export: avoid 'wait $!' for process substitution
Bash 4.4, released in 2016, supports 'wait $!' to check the exit status
of a process substitution, but it seems too new.

Some people using older bash versions (on CentOS 7, Ubuntu 16.04, etc.)
reported an error like this:

  ./scripts/check-local-export: line 54: wait: pid 17328 is not a child of this shell

I used the process substitution to avoid a pipeline, which executes each
command in a subshell. If the while-loop is executed in the subshell
context, variable changes within are lost after the subshell terminates.

Fortunately, Bash 4.2, released in 2011, supports the 'lastpipe' option,
which makes the last element of a pipeline run in the current shell process.

Switch to the pipeline with 'lastpipe' solution, and also set 'pipefail'
to catch errors from ${NM}.

Add the bash requirement to Documentation/process/changes.rst.

Fixes: 31cb50b559 ("kbuild: check static EXPORT_SYMBOL* by script instead of modpost")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-10 03:47:13 +09:00
Linus Torvalds
6bfb56e93b cert host tools: Stop complaining about deprecated OpenSSL functions
OpenSSL 3.0 deprecated the OpenSSL's ENGINE API.  That is as may be, but
the kernel build host tools still use it.  Disable the warning about
deprecated declarations until somebody who cares fixes it.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-06-08 13:18:39 -07:00
Masahiro Yamada
49c3ca34f7 scripts/nsdeps: adjust to the format change of *.mod files
Commit 22f26f2177 ("kbuild: get rid of duplication in *.mod files")
changed the format of *.mod files to put one object per line, but missed
to adjust scripts/nsdeps.

Fixes: 22f26f2177 ("kbuild: get rid of duplication in *.mod files")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-08 20:14:13 +09:00
Kevin Locke
7bf179de5b kbuild: avoid regex RS for POSIX awk
In 22f26f2177 awk was added to deduplicate *.mod files.  The awk
invocation passes -v RS='( |\n)' to match a space or newline character
as the record separator.  Unfortunately, POSIX states[1]

> If RS contains more than one character, the results are unspecified.

Some implementations (such as the One True Awk[2] used by the BSDs) do
not treat RS as a regular expression.  When awk does not support regex
RS, build failures such as the following are produced (first error using
allmodconfig):

      CC [M]  arch/x86/events/intel/uncore.o
      CC [M]  arch/x86/events/intel/uncore_nhmex.o
      CC [M]  arch/x86/events/intel/uncore_snb.o
      CC [M]  arch/x86/events/intel/uncore_snbep.o
      CC [M]  arch/x86/events/intel/uncore_discovery.o
      LD [M]  arch/x86/events/intel/intel-uncore.o
    ld: cannot find uncore_nhmex.o: No such file or directory
    ld: cannot find uncore_snb.o: No such file or directory
    ld: cannot find uncore_snbep.o: No such file or directory
    ld: cannot find uncore_discovery.o: No such file or directory
    make[3]: *** [scripts/Makefile.build:422: arch/x86/events/intel/intel-uncore.o] Error 1
    make[2]: *** [scripts/Makefile.build:487: arch/x86/events/intel] Error 2
    make[1]: *** [scripts/Makefile.build:487: arch/x86/events] Error 2
    make: *** [Makefile:1839: arch/x86] Error 2

To avoid this, use printf(1) to produce a newline between each object
path, instead of the space produced by echo(1), so that the default RS
can be used by awk.

[1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/awk.html
[2]: https://github.com/onetrueawk/awk

Fixes: 22f26f2177 ("kbuild: get rid of duplication in *.mod files")
Signed-off-by: Kevin Locke <kevin@kevinlocke.name>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-08 01:27:26 +09:00
Josh Poimboeuf
dcea997bee faddr2line: Fix overlapping text section failures, the sequel
If a function lives in a section other than .text, but .text also exists
in the object, faddr2line may wrongly assume .text.  This can result in
comically wrong output.  For example:

  $ scripts/faddr2line vmlinux.o enter_from_user_mode+0x1c
  enter_from_user_mode+0x1c/0x30:
  find_next_bit at /home/jpoimboe/git/linux/./include/linux/find.h:40
  (inlined by) perf_clear_dirty_counters at /home/jpoimboe/git/linux/arch/x86/events/core.c:2504

Fix it by passing the section name to addr2line, unless the object file
is vmlinux, in which case the symbol table uses absolute addresses.

Fixes: 1d1a0e7c51 ("scripts/faddr2line: Fix overlapping text section failures")
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/7d25bc1408bd3a750ac26e60d2f2815a5f4a8363.1654130536.git.jpoimboe@kernel.org
2022-06-06 11:50:11 -07:00
Linus Torvalds
44688ffd11 Merge tag 'objtool-urgent-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fixes from Thomas Gleixner:

 - Handle __ubsan_handle_builtin_unreachable() correctly and treat it as
   noreturn

 - Allow architectures to select uaccess validation

 - Use the non-instrumented bit test for test_cpu_has() to prevent
   escape from non-instrumentable regions

 - Use arch_ prefixed atomics for JUMP_LABEL=n builds to prevent escape
   from non-instrumentable regions

 - Mark a few tiny inline as __always_inline to prevent GCC from
   bringing them out of line and instrumenting them

 - Mark the empty stub context_tracking_enabled() as always inline as
   GCC brings them out of line and instruments the empty shell

 - Annotate ex_handler_msr_mce() as dead end

* tag 'objtool-urgent-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/extable: Annotate ex_handler_msr_mce() as a dead end
  context_tracking: Always inline empty stubs
  x86: Always inline on_thread_stack() and current_top_of_stack()
  jump_label,noinstr: Avoid instrumentation for JUMP_LABEL=n builds
  x86/cpu: Elide KCSAN for cpu_has() and friends
  objtool: Mark __ubsan_handle_builtin_unreachable() as noreturn
  objtool: Add CONFIG_HAVE_UACCESS_VALIDATION
2022-06-05 09:45:27 -07:00
Linus Torvalds
71e80720db Merge tag 'kbuild-v5.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:

 - Fix build regressions for parisc, csky, nios2, openrisc

 - Simplify module builds for CONFIG_LTO_CLANG and CONFIG_X86_KERNEL_IBT

 - Remove arch/parisc/nm, which was presumably a workaround for old
   tools

 - Check the odd combination of EXPORT_SYMBOL and 'static' precisely

 - Make external module builds robust against "too long argument error"

 - Support j, k keys for moving the cursor in nconfig

* tag 'kbuild-v5.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
  kbuild: Allow to select bash in a modified environment
  scripts: kconfig: nconf: make nconfig accept jk keybindings
  modpost: use fnmatch() to simplify match()
  modpost: simplify mod->name allocation
  kbuild: factor out the common objtool arguments
  kbuild: move vmlinux.o link to scripts/Makefile.vmlinux_o
  kbuild: clean .tmp_* pattern by make clean
  kbuild: remove redundant cleanups in scripts/link-vmlinux.sh
  kbuild: rebuild multi-object modules when objtool is updated
  kbuild: add cmd_and_savecmd macro
  kbuild: make *.mod rule robust against too long argument error
  kbuild: make built-in.a rule robust against too long argument error
  kbuild: check static EXPORT_SYMBOL* by script instead of modpost
  parisc: remove arch/parisc/nm
  kbuild: do not create *.prelink.o for Clang LTO or IBT
  kbuild: replace $(linked-object) with CONFIG options
  kbuild: do not try to parse *.cmd files for objects provided by compiler
  kbuild: replace $(if A,A,B) with $(or A,B) in scripts/Makefile.modpost
  modpost: squash if...else-if in find_elf_symbol2()
  modpost: reuse ARRAY_SIZE() macro for section_mismatch()
  ...
2022-06-05 09:06:03 -07:00
Schspa Shi
42ce60aa5a kbuild: Allow to select bash in a modified environment
This fixes the build error when the system has a default bash version
which is too old to support associative array variables.

The build error log as fellowing:
linux/scripts/check-local-export: line 11: declare: -A: invalid option
declare: usage: declare [-afFirtx] [-p] [name[=value] ...]

Signed-off-by: Schspa Shi <schspa@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-05 06:20:58 +09:00
Isak Ellmer
2bbb486162 scripts: kconfig: nconf: make nconfig accept jk keybindings
Make nconfig accept jk keybindings for movement in addition to arrow
keys.

Signed-off-by: Isak Ellmer <isak01@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-05 06:20:57 +09:00
Masahiro Yamada
a89227d769 modpost: use fnmatch() to simplify match()
Replace the own implementation for wildcard (glob) matching with
a function call to fnmatch().

Also, change the return type to 'bool'.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-05 06:20:57 +09:00
Masahiro Yamada
8c9ce89c5b modpost: simplify mod->name allocation
mod->name is set to the ELF filename with the suffix ".o" stripped.

The current code calls strdup() and free() to manipulate the string,
but a simpler approach is to pass new_module() with the name length
subtracted by 2.

Also, check if the passed filename ends with ".o" before stripping it.

The current code blindly chops the suffix:

    tmp[strlen(tmp) - 2] = '\0'

It will cause buffer under-run if strlen(tmp) < 2;

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-06-05 06:20:57 +09:00
Masahiro Yamada
b42d230650 kbuild: factor out the common objtool arguments
scripts/Makefile.build and scripts/link-vmlinux.sh have similar setups
for the objtool arguments.

It was difficult to factor out them because all the vmlinux build rules
were written in a shell script. It is somewhat tedious to touch the two
files every time a new objtool option is supported.

To reduce the code duplication, move the objtool for vmlinux.o into
scripts/Makefile.vmlinux_o. Then, move the common macros to Makefile.lib
so they are shared between Makefile.build and Makefile.vmlinux_o.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-05 06:20:57 +09:00
Masahiro Yamada
5d45950dfb kbuild: move vmlinux.o link to scripts/Makefile.vmlinux_o
This is a preparation for moving the objtool rule in the next commit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-05 06:20:57 +09:00
Masahiro Yamada
b0d6207bad kbuild: clean .tmp_* pattern by make clean
Change the "make clean" rule to remove all the .tmp_* files.

.tmp_objdiff is the only exception, which should be removed by
"make mrproper".

Rename the record directory of objdiff, .tmp_objdiff to .objdiff to
avoid the removal by "make clean".

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-05 06:20:57 +09:00
Linus Torvalds
c6f2f3e2c8 Merge tag 'loongarch-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull initial Loongarch architecture code from Arnd Bergmann:
 "This is the majority of the loongarch architecture code, including the
  final system call interface and all core functionality.

  It still misses three sets of peripheral but vital patches to add
  support for other subsystems, which have yet to pass review:

   - The drivers/firmware/efi stub for booting from a standard UEFI
     firmware implementation. Both the original custom boot interface
     and a draft implementation of the EFI stub did not make it, so it
     is currently impossible to boot the kernel, until the loongarch
     specific portions get accepted into the UEFI subsystem

   - The drivers/irqchip/irq-loongson-*.c drivers are shared with the
     the MIPS port, but currently lack support for ACPI based booting,
     which will get merged through the irqchip subsystem.

   - Similarly, the drivers/pci/controller/pci-loongson.c needs to be
     modified for ACPI support, which will be merged through the PCI
     subsystem.

  While the port cannot actually be used before all the above are
  merged, having it in 5.19 helps to establish the user space ABI for
  the libc ports to build on, and to help any treewide changes in the
  mainline kernel get applied here as well.

  A gcc-12 based tool chains for build testing is now included in

    https://mirrors.edge.kernel.org/pub/tools/crosstool/"

Original description from Huacai Chen:
 "LoongArch is a new RISC ISA, which is a bit like MIPS or RISC-V.
  LoongArch includes a reduced 32-bit version (LA32R), a standard 32-bit
  version (LA32S) and a 64-bit version (LA64). LoongArch use ACPI as its
  boot protocol LoongArch-specific interrupt controllers (similar to APIC)
  are already added in the next revision of ACPI Specification (current
  revision is 6.4).

  This patchset is adding basic LoongArch support in mainline kernel, we
  can see a complete snapshot here:

    https://github.com/loongson/linux/tree/loongarch-next
    https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-next

  Cross-compile tool chain to build kernel:

    https://github.com/loongson/build-tools/releases/download/2021.12.21/loongarch64-clfs-2022-03-03-cross-tools-gcc-glibc.tar.xz

  A CLFS-based Linux distro:

    https://github.com/loongson/build-tools/releases/download/2021.12.21/loongarch64-clfs-system-2022-03-03.tar.bz2

  Open-source tool chain which is under review (Binutils and Gcc are already upstream):

    https://github.com/loongson/binutils-gdb/tree/upstream_v3.1
    https://github.com/loongson/gcc/tree/loongarch_upstream_v6.3
    https://github.com/loongson/glibc/tree/loongarch_2_35_dev_v2.2

  Loongson and LoongArch documentations:

    https://github.com/loongson/LoongArch-Documentation

  LoongArch-specific interrupt controllers:

    https://mantis.uefi.org/mantis/view.php?id=2203
    https://mantis.uefi.org/mantis/view.php?id=2313"

Link: https://lore.kernel.org/lkml/20220603072053.35005-1-chenhuacai@loongson.cn/

* tag 'loongarch-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (24 commits)
  MAINTAINERS: Add maintainer information for LoongArch
  LoongArch: Add Loongson-3 default config file
  LoongArch: Add Non-Uniform Memory Access (NUMA) support
  LoongArch: Add multi-processor (SMP) support
  LoongArch: Add VDSO and VSYSCALL support
  LoongArch: Add some library functions
  LoongArch: Add misc common routines
  LoongArch: Add ELF and module support
  LoongArch: Add signal handling support
  LoongArch: Add system call support
  LoongArch: Add memory management
  LoongArch: Add process management
  LoongArch: Add exception/interrupt handling
  LoongArch: Add boot and setup routines
  LoongArch: Add other common headers
  LoongArch: Add atomic/locking headers
  LoongArch: Add CPU definition headers
  LoongArch: Add build infrastructure
  LoongArch: Add writecombine support for drm
  LoongArch: Add ELF-related definitions
  ...
2022-06-03 14:09:21 -07:00
Linus Torvalds
500a434fc5 Merge tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
 "Here is the set of driver core changes for 5.19-rc1.

  Lots of tiny driver core changes and cleanups happened this cycle, but
  the two major things are:

   - firmware_loader reorganization and additions including the ability
     to have XZ compressed firmware images and the ability for userspace
     to initiate the firmware load when it needs to, instead of being
     always initiated by the kernel. FPGA devices specifically want this
     ability to have their firmware changed over the lifetime of the
     system boot, and this allows them to work without having to come up
     with yet-another-custom-uapi interface for loading firmware for
     them.

   - physical location support added to sysfs so that devices that know
     this information, can tell userspace where they are located in a
     common way. Some ACPI devices already support this today, and more
     bus types should support this in the future.

  Smaller changes include:

   - driver_override api cleanups and fixes

   - error path cleanups and fixes

   - get_abi script fixes

   - deferred probe timeout changes.

  It's that last change that I'm the most worried about. It has been
  reported to cause boot problems for a number of systems, and I have a
  tested patch series that resolves this issue. But I didn't get it
  merged into my tree before 5.18-final came out, so it has not gotten
  any linux-next testing.

  I'll send the fixup patches (there are 2) as a follow-on series to this
  pull request.

  All have been tested in linux-next for weeks, with no reported issues
  other than the above-mentioned boot time-outs"

* tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
  driver core: fix deadlock in __device_attach
  kernfs: Separate kernfs_pr_cont_buf and rename_lock.
  topology: Remove unused cpu_cluster_mask()
  driver core: Extend deferred probe timeout on driver registration
  MAINTAINERS: add Russ Weight as a firmware loader maintainer
  driver: base: fix UAF when driver_attach failed
  test_firmware: fix end of loop test in upload_read_show()
  driver core: location: Add "back" as a possible output for panel
  driver core: location: Free struct acpi_pld_info *pld
  driver core: Add "*" wildcard support to driver_async_probe cmdline param
  driver core: location: Check for allocations failure
  arch_topology: Trace the update thermal pressure
  kernfs: Rename kernfs_put_open_node to kernfs_unlink_open_file.
  export: fix string handling of namespace in EXPORT_SYMBOL_NS
  rpmsg: use local 'dev' variable
  rpmsg: Fix calling device_lock() on non-initialized device
  firmware_loader: describe 'module' parameter of firmware_upload_register()
  firmware_loader: Move definitions from sysfs_upload.h to sysfs.h
  firmware_loader: Fix configs for sysfs split
  selftests: firmware: Add firmware upload selftests
  ...
2022-06-03 11:48:47 -07:00
Linus Torvalds
6f9b5ed8ca Merge tag 'char-misc-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char / misc / other smaller driver subsystem updates from Greg KH:
 "Here is the large set of char, misc, and other driver subsystem
  updates for 5.19-rc1. The merge request for this has been delayed as I
  wanted to get lots of linux-next testing due to some late arrivals of
  changes for the habannalabs driver.

  Highlights of this merge are:

   - habanalabs driver updates for new hardware types and fixes and
     other updates

   - IIO driver tree merge which includes loads of new IIO drivers and
     cleanups and additions

   - PHY driver tree merge with new drivers and small updates to
     existing ones

   - interconnect driver tree merge with fixes and updates

   - soundwire driver tree merge with some small fixes

   - coresight driver tree merge with small fixes and updates

   - mhi bus driver tree merge with lots of updates and new device
     support

   - firmware driver updates

   - fpga driver updates

   - lkdtm driver updates (with a merge conflict, more on that below)

   - extcon driver tree merge with small updates

   - lots of other tiny driver updates and fixes and cleanups, full
     details in the shortlog.

  All of these have been in linux-next for almost 2 weeks with no
  reported problems"

* tag 'char-misc-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (387 commits)
  habanalabs: use separate structure info for each error collect data
  habanalabs: fix missing handle shift during mmap
  habanalabs: remove hdev from hl_ctx_get args
  habanalabs: do MMU prefetch as deferred work
  habanalabs: order memory manager messages
  habanalabs: return -EFAULT on copy_to_user error
  habanalabs: use NULL for eventfd
  habanalabs: update firmware header
  habanalabs: add support for notification via eventfd
  habanalabs: add topic to memory manager buffer
  habanalabs: handle race in driver fini
  habanalabs: add device memory scrub ability through debugfs
  habanalabs: use unified memory manager for CB flow
  habanalabs: unified memory manager new code for CB flow
  habanalabs/gaudi: set arbitration timeout to a high value
  habanalabs: add put by handle method to memory manager
  habanalabs: hide memory manager page shift
  habanalabs: Add separate poll interval value for protocol
  habanalabs: use get_task_pid() to take PID
  habanalabs: add prefetch flag to the MAP operation
  ...
2022-06-03 11:36:34 -07:00
Linus Torvalds
04d93b2b8b Merge tag 'spdx-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx
Pull SPDX updates from Greg KH:
 "Here are some SPDX license marker changes.

  The SPDX-labeling effort has started to pick up again, so here are
  some changes for various parts of the tree that are related to this
  effort.

  Included in here are:

   - freevxfs license updates

   - spihash.c license cleanups

   - spdxcheck script updates to make things easier to work with going
     forward

  All of the license updates came from the original authors/copyright
  holders of the code involved.

  All of these have been in linux-next for weeks with no reported
  issues"

* tag 'spdx-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  siphash: add SPDX tags as sole licensing authority
  scripts/spdxcheck: Exclude top-level README
  scripts/spdxcheck: Exclude MAINTAINERS/CREDITS
  scripts/spdxcheck: Exclude config directories
  scripts/spdxcheck: Put excluded files and directories into a separate file
  scripts/spdxcheck: Add option to display files without SPDX
  scripts/spdxcheck: Add [sub]directory statistics
  scripts/spdxcheck: Add directory statistics
  scripts/spdxcheck: Add percentage to statistics
  freevxfs: relicense to GPLv2 only
2022-06-03 10:34:34 -07:00
Huacai Chen
fa96b57c14 LoongArch: Add build infrastructure
Add Kbuild, Makefile, Kconfig and link script for LoongArch build
infrastructure.

Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-06-03 20:09:27 +08:00
Huacai Chen
08145b087e LoongArch: Add ELF-related definitions
Add ELF-related definitions for LoongArch, including: EM_LOONGARCH,
KEXEC_ARCH_LOONGARCH, AUDIT_ARCH_LOONGARCH32, AUDIT_ARCH_LOONGARCH64
and NT_LOONGARCH_*.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-06-03 20:09:27 +08:00
Linus Torvalds
50fd82b3a9 Merge tag 'docs-5.19-2' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet:
 "A handful of late-arriving documentation fixes and the addition of an
  SVG tux logo which, I'm assured, we're going to want"

* tag 'docs-5.19-2' of git://git.lwn.net/linux:
  documentation: Format button_dev as a pointer.
  docs: add SVG version of the Linux logo
  docs: move Linux logo into a new `images` folder
  docs: blockdev: change title to match section content
  docs/conf.py: Cope with removal of language=None in Sphinx 5.0.0
2022-06-02 15:36:06 -07:00
Miguel Ojeda
fae35da4ac docs: move Linux logo into a new images folder
Having assets in the top-level `Documentation` directory can make
it harder to find the documents one needs, especially if we want
to add more of them later on.

Instead, create a new `images` folder inside it that is used
to hold assets such as logos.

In addition, update the reference in `scripts/spdxcheck-test.sh`.

Link: https://lore.kernel.org/lkml/8735hicoy7.fsf@meer.lwn.net/
Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20220528153132.8636-1-ojeda@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-06-01 09:32:45 -06:00
Masahiro Yamada
a78b6afa99 kbuild: remove redundant cleanups in scripts/link-vmlinux.sh
These are cleaned by the top Makefile.

vmlinux.o and .vmlinux.d matches the '*.[aios]' and '.*.d' patterns
respectively.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:29 +09:00
Masahiro Yamada
f6b66ca4f3 kbuild: rebuild multi-object modules when objtool is updated
When CONFIG_LTO_CLANG or CONFIG_X86_KERNEL_IBT is enabled, objtool for
multi-object modules is postponed until the objects are linked together.

Make sure to re-run objtool and re-link multi-object modules when
objtool is updated.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:29 +09:00
Masahiro Yamada
ebd191b38c kbuild: add cmd_and_savecmd macro
Separate out the command execution part of if_changed, as we did
for if_changed_dep.

This allows us to reuse it in if_changed_rule.

  define rule_foo
          $(call cmd_and_savecmd,foo)
          $(call cmd,bar)
  endef

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:29 +09:00
Masahiro Yamada
c6031b1dbb kbuild: make *.mod rule robust against too long argument error
Like built-in.a, the command length of the *.mod rule scales with
the depth of the directory times the number of objects in the Makefile.

Add $(obj)/ by the shell command (awk) instead of by Make's builtin
function.

In-tree modules still have some room to the limit (ARG_MAX=2097152),
but this is more future-proof for big modules in a deep directory.

For example, you can build i915 as a module (CONFIG_DRM_I915=m) and
compare drivers/gpu/drm/i915/.i915.mod.cmd with/without this commit.

The issue is more critical for external modules because the M= path
can be very long as Jeff Johnson reported before [1].

[1] https://lore.kernel.org/linux-kbuild/4c02050c4e95e4cb8cc04282695f8404@codeaurora.org/

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:29 +09:00
Masahiro Yamada
cd968b97c4 kbuild: make built-in.a rule robust against too long argument error
Kbuild runs at the top of objtree instead of changing the working
directory to subdirectories. I think this design is nice overall but
some commands have a scalability issue.

The build command of built-in.a is one of them whose length scales with:

    O(D * N)

Here, D is the length of the directory path (i.e. $(obj)/ prefix),
N is the number of objects in the Makefile, O() is the big O notation.

The deeper directory the Makefile directory is located, the more easily
it will hit the too long argument error.

We can make it better. Trim the $(obj)/ by Make's builtin function, and
restore it by a shell command (sed).

With this, the command length scales with:

    O(D + N)

In-tree modules still have some room to the limit (ARG_MAX=2097152),
but this is more future-proof for big modules in a deep directory.

For example, you can build i915 as builtin (CONFIG_DRM_I915=y) and
compare drivers/gpu/drm/i915/.built-in.a.cmd with/without this commit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:29 +09:00
Masahiro Yamada
31cb50b559 kbuild: check static EXPORT_SYMBOL* by script instead of modpost
The 'static' specifier and EXPORT_SYMBOL() are an odd combination.

Commit 15bfc2348d ("modpost: check for static EXPORT_SYMBOL*
functions") tried to detect it, but this check has false negatives.

Here is the sample code.

  Makefile:

    obj-y += foo1.o foo2.o

  foo1.c:

    #include <linux/export.h>
    static void foo(void) {}
    EXPORT_SYMBOL(foo);

  foo2.c:

    void foo(void) {}

foo1.c exports the static symbol 'foo', but modpost cannot catch it
because it is fooled by foo2.c, which has a global symbol with the
same name.

s->is_static is cleared if a global symbol with the same name is found
somewhere, but EXPORT_SYMBOL() and the global symbol do not necessarily
belong to the same compilation unit.

This check should be done per compilation unit, but I do not know how
to do it in modpost. modpost runs against vmlinux.o or modules, which
merges multiple objects, then forgets their origin.

modpost cannot parse individual objects because they may not be ELF but
LLVM IR when CONFIG_LTO_CLANG=y.

Add a simple bash script to parse the output from ${NM}. This works for
CONFIG_LTO_CLANG=y because llvm-nm can dump symbols of LLVM IR files.

Revert 15bfc2348d.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:02 +09:00
Masahiro Yamada
c25e1c5582 kbuild: do not create *.prelink.o for Clang LTO or IBT
When CONFIG_LTO_CLANG=y, additional intermediate *.prelink.o is created
for each module. Also, objtool is postponed until LLVM IR is converted
to ELF.

CONFIG_X86_KERNEL_IBT works in a similar way to postpone objtool until
objects are merged together.

This commit stops generating *.prelink.o, so the build flow will look
similar with/without LTO.

The following figures show how the LTO build currently works, and
how this commit is changing it.

Current build flow
==================

 [1] single-object module

                                      $(LD)
           $(CC)                     +objtool              $(LD)
    foo.c --------------------> foo.o -----> foo.prelink.o -----> foo.ko
                              (LLVM IR)          (ELF)       |    (ELF)
                                                             |
                                                 foo.mod.o --/
                                                 (LLVM IR)

 [2] multi-object module
                                      $(LD)
           $(CC)         $(AR)       +objtool               $(LD)
    foo1.c -----> foo1.o -----> foo.o -----> foo.prelink.o -----> foo.ko
                           |  (archive)          (ELF)       |    (ELF)
    foo2.c -----> foo2.o --/                                 |
                 (LLVM IR)                       foo.mod.o --/
                                                 (LLVM IR)

  One confusion is that foo.o in multi-object module is an archive
  despite of its suffix.

New build flow
==============

 [1] single-object module

  Since there is only one object, there is no need to keep the LLVM IR.
  Use $(CC)+$(LD) to generate an ELF object in one build rule. When LTO
  is disabled, $(LD) is unneeded because $(CC) produces an ELF object.

               $(CC)+$(LD)+objtool              $(LD)
    foo.c ----------------------------> foo.o ---------> foo.ko
                                        (ELF)     |      (ELF)
                                                  |
                                      foo.mod.o --/
                                      (LLVM IR)

 [2] multi-object module

  Previously, $(AR) was used to combine LLVM IR files into an archive,
  but there was no technical reason to do so. Use $(LD) to merge them
  into a single ELF object.

                               $(LD)
             $(CC)            +objtool          $(LD)
    foo1.c ---------> foo1.o ---------> foo.o ---------> foo.ko
                                 |      (ELF)     |      (ELF)
    foo2.c ---------> foo2.o ----/                |
                     (LLVM IR)        foo.mod.o --/
                                      (LLVM IR)

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
2022-05-29 18:39:35 +09:00