Commit Graph

260 Commits

Author SHA1 Message Date
Masahiro Yamada
65c5545287 kbuild: avoid build error when single DTB is turned into composite DTB
[ Upstream commit 712aba5543b88996bc4682086471076fbf048927 ]

As commit afa974b771 ("kbuild: add real-prereqs shorthand for
$(filter-out FORCE,$^)") explained, $(real-prereqs) is not just a list
of objects when linking a multi-object module. If a single-object module
is turned into a multi-object module, $^ (and therefore $(real-prereqs)
as well) contains header files recorded in the *.cmd file. Such headers
must be filtered out.

Now that a DTB can be built either from a single source or multiple
source files, the same issue can occur.

Consider the following scenario:

First, foo.dtb is implemented as a single-blob device tree.

The code looks something like this:

[Sample Code 1]

  Makefile:

      dtb-y += foo.dtb

  foo.dts:

    #include <dt-bindings/gpio/gpio.h>
    /dts-v1/;
    / { };

When it is compiled, .foo.dtb.cmd records that foo.dtb depends on
scripts/dtc/include-prefixes/dt-bindings/gpio/gpio.h.

Later, foo.dtb is split into a base and an overlay. The code looks
something like this:

[Sample Code 2]

  Makefile:

      dtb-y += foo.dtb
      foo-dtbs := foo-base.dtb foo-addon.dtbo

  foo-base.dts:

    #include <dt-bindings/gpio/gpio.h>
    /dts-v1/;
    / { };

  foo-addon.dtso:

    /dts-v1/;
    /plugin/;
    / { };

If you rebuild foo.dtb without 'make clean', you will get this error:

    Overlay 'scripts/dtc/include-prefixes/dt-bindings/gpio/gpio.h' is incomplete

$(real-prereqs) contains not only foo-base.dtb and foo-addon.dtbo but
also scripts/dtc/include-prefixes/dt-bindings/gpio/gpio.h, which is
passed to scripts/dtc/fdtoverlay.

Fixes: 15d16d6dad ("kbuild: Add generic rule to apply fdtoverlay")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03 08:49:48 +02:00
Linus Torvalds
27bc50fc90 Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
   linux-next for a couple of months without, to my knowledge, any
   negative reports (or any positive ones, come to that).

 - Also the Maple Tree from Liam Howlett. An overlapping range-based
   tree for vmas. It it apparently slightly more efficient in its own
   right, but is mainly targeted at enabling work to reduce mmap_lock
   contention.

   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.

   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   at [1]. This has yet to be addressed due to Liam's unfortunately
   timed vacation. He is now back and we'll get this fixed up.

 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
   clang-generated instrumentation to detect used-unintialized bugs down
   to the single bit level.

   KMSAN keeps finding bugs. New ones, as well as the legacy ones.

 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.

 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
   support file/shmem-backed pages.

 - userfaultfd updates from Axel Rasmussen

 - zsmalloc cleanups from Alexey Romanov

 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
   memory-failure

 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.

 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.

 - memcg cleanups from Kairui Song.

 - memcg fixes and cleanups from Johannes Weiner.

 - Vishal Moola provides more folio conversions

 - Zhang Yi removed ll_rw_block() :(

 - migration enhancements from Peter Xu

 - migration error-path bugfixes from Huang Ying

 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths. For optimizations by PMEM drivers, DRM
   drivers, etc.

 - vma merging improvements from Jakub Matěn.

 - NUMA hinting cleanups from David Hildenbrand.

 - xu xin added aditional userspace visibility into KSM merging
   activity.

 - THP & KSM code consolidation from Qi Zheng.

 - more folio work from Matthew Wilcox.

 - KASAN updates from Andrey Konovalov.

 - DAMON cleanups from Kaixu Xia.

 - DAMON work from SeongJae Park: fixes, cleanups.

 - hugetlb sysfs cleanups from Muchun Song.

 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
  hugetlb: allocate vma lock for all sharable vmas
  hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer
  hugetlb: fix vma lock handling during split vma and range unmapping
  mglru: mm/vmscan.c: fix imprecise comments
  mm/mglru: don't sync disk for each aging cycle
  mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
  mm: memcontrol: use do_memsw_account() in a few more places
  mm: memcontrol: deprecate swapaccounting=0 mode
  mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
  mm/secretmem: remove reduntant return value
  mm/hugetlb: add available_huge_pages() func
  mm: remove unused inline functions from include/linux/mm_inline.h
  selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
  selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
  selftests/vm: add thp collapse shmem testing
  selftests/vm: add thp collapse file and tmpfs testing
  selftests/vm: modularize thp collapse memory operations
  selftests/vm: dedup THP helpers
  mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
  mm/madvise: add file and shmem support to MADV_COLLAPSE
  ...
2022-10-10 17:53:04 -07:00
Linus Torvalds
706eacadd5 Merge tag 'devicetree-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring:
 "DT core:

   - Fix node refcounting in of_find_last_cache_level()

   - Constify device_node in of_device_compatible_match()

   - Fix 'dma-ranges' handling in bus controller nodes

   - Fix handling of initrd start > end

   - Improve error reporting in of_irq_init()

   - Taint kernel on DT unittest running

   - Use strscpy instead of strlcpy

   - Add a build target, dt_compatible_check, to check for compatible
     strings used in kernel sources against compatible strings in DT
     schemas.

   - Handle DT_SCHEMA_FILES changes when rebuilding

  DT bindings:

   - LED bindings for MT6370 PMIC

   - Convert Mediatek mtk-gce mailbox, MIPS CPU interrupt controller,
     mt7621 I2C, virtio,pci-iommu, nxp,tda998x, QCom fastrpc, qcom,pdc,
     and arm,versatile-sysreg to DT schema format

   - Add nvmem cells to u-boot,env schema

   - Add more LED_COLOR_ID definitions

   - Require 'opp-table' uses to be a node

   - Various schema fixes to match QEMU 'virt' DT usage

   - Tree wide dropping of redundant 'Device Tree Binding' in schema
     titles

   - More (unevaluated|additional)Properties fixes in schema child nodes

   - Drop various redundant minItems equal to maxItems"

* tag 'devicetree-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (62 commits)
  of: base: Shift refcount decrement in of_find_last_cache_level()
  dt-bindings: leds: Add MediaTek MT6370 flashlight
  dt-bindings: leds: mt6370: Add MediaTek MT6370 current sink type LED indicator
  dt-bindings: mailbox: Convert mtk-gce to DT schema
  of: base: make of_device_compatible_match() accept const device node
  of: Fix "dma-ranges" handling for bus controllers
  of: fdt: Remove unused struct fdt_scan_status
  dt-bindings: display: st,stm32-dsi: Handle data-lanes in DSI port node
  dt-bindings: timer: Add power-domains for TI timer-dm on K3
  dt: Add a check for undocumented compatible strings in kernel
  kbuild: take into account DT_SCHEMA_FILES changes while checking dtbs
  dt-bindings: interrupt-controller: migrate MIPS CPU interrupt controller text bindings to YAML
  dt-bindings: i2c: migrate mt7621 text bindings to YAML
  dt-bindings: power: gpcv2: correct patternProperties
  dt-bindings: virtio: Convert virtio,pci-iommu to DT schema
  dt-bindings: timer: arm,arch_timer: Allow dual compatible string
  dt-bindings: arm: cpus: Add kryo240 compatible
  dt-bindings: display: bridge: nxp,tda998x: Convert to json-schema
  dt-bindings: nvmem: u-boot,env: add basic NVMEM cells
  dt-bindings: remoteproc: qcom,adsp: enforce smd-edge schema
  ...
2022-10-10 13:13:51 -07:00
Linus Torvalds
8afc66e8d4 Merge tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

 - Remove potentially incomplete targets when Kbuid is interrupted by
   SIGINT etc in case GNU Make may miss to do that when stderr is piped
   to another program.

 - Rewrite the single target build so it works more correctly.

 - Fix rpm-pkg builds with V=1.

 - List top-level subdirectories in ./Kbuild.

 - Ignore auto-generated __kstrtab_* and __kstrtabns_* symbols in
   kallsyms.

 - Avoid two different modules in lib/zstd/ having shared code, which
   potentially causes building the common code as build-in and modular
   back-and-forth.

 - Unify two modpost invocations to optimize the build process.

 - Remove head-y syntax in favor of linker scripts for placing
   particular sections in the head of vmlinux.

 - Bump the minimal GNU Make version to 3.82.

 - Clean up misc Makefiles and scripts.

* tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (41 commits)
  docs: bump minimal GNU Make version to 3.82
  ia64: simplify esi object addition in Makefile
  Revert "kbuild: Check if linker supports the -X option"
  kbuild: rebuild .vmlinux.export.o when its prerequisite is updated
  kbuild: move modules.builtin(.modinfo) rules to Makefile.vmlinux_o
  zstd: Fixing mixed module-builtin objects
  kallsyms: ignore __kstrtab_* and __kstrtabns_* symbols
  kallsyms: take the input file instead of reading stdin
  kallsyms: drop duplicated ignore patterns from kallsyms.c
  kbuild: reuse mksysmap output for kallsyms
  mksysmap: update comment about __crc_*
  kbuild: remove head-y syntax
  kbuild: use obj-y instead extra-y for objects placed at the head
  kbuild: hide error checker logs for V=1 builds
  kbuild: re-run modpost when it is updated
  kbuild: unify two modpost invocations
  kbuild: move vmlinux.o rule to the top Makefile
  kbuild: move .vmlinux.objs rule to Makefile.modpost
  kbuild: list sub-directories in ./Kbuild
  Makefile.compiler: replace cc-ifversion with compiler-specific macros
  ...
2022-10-10 12:00:45 -07:00
Alexander Potapenko
f80be4571b kmsan: add KMSAN runtime core
For each memory location KernelMemorySanitizer maintains two types of
metadata:

1. The so-called shadow of that location - а byte:byte mapping describing
   whether or not individual bits of memory are initialized (shadow is 0)
   or not (shadow is 1).
2. The origins of that location - а 4-byte:4-byte mapping containing
   4-byte IDs of the stack traces where uninitialized values were
   created.

Each struct page now contains pointers to two struct pages holding KMSAN
metadata (shadow and origins) for the original struct page.  Utility
routines in mm/kmsan/core.c and mm/kmsan/shadow.c handle the metadata
creation, addressing, copying and checking.  mm/kmsan/report.c performs
error reporting in the cases an uninitialized value is used in a way that
leads to undefined behavior.

KMSAN compiler instrumentation is responsible for tracking the metadata
along with the kernel memory.  mm/kmsan/instrumentation.c provides the
implementation for instrumentation hooks that are called from files
compiled with -fsanitize=kernel-memory.

To aid parameter passing (also done at instrumentation level), each
task_struct now contains a struct kmsan_task_state used to track the
metadata of function parameters and return values for that task.

Finally, this patch provides CONFIG_KMSAN that enables KMSAN, and declares
CFLAGS_KMSAN, which are applied to files compiled with KMSAN.  The
KMSAN_SANITIZE:=n Makefile directive can be used to completely disable
KMSAN instrumentation for certain files.

Similarly, KMSAN_ENABLE_CHECKS:=n disables KMSAN checks and makes newly
created stack memory initialized.

Users can also use functions from include/linux/kmsan-checks.h to mark
certain memory regions as uninitialized or initialized (this is called
"poisoning" and "unpoisoning") or check that a particular region is
initialized.

Link: https://lkml.kernel.org/r/20220915150417.722975-12-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:19 -07:00
Masahiro Yamada
5750121ae7 kbuild: list sub-directories in ./Kbuild
Use the ordinary obj-y syntax to list subdirectories.

Note1:
Previously, the link order of lib-y depended on CONFIG_MODULES; lib-y
was linked before drivers-y when CONFIG_MODULES=y, otherwise after
drivers-y. This was a bug of commit 7273ad2b08 ("kbuild: link lib-y
objects to vmlinux forcibly when CONFIG_MODULES=y"), but it was not a
big deal after all. Now, all objects listed in lib-y are linked last,
irrespective of CONFIG_MODULES.

Note2:
Finally, the single target build in arch/*/lib/ works correctly. There was
a bug report about this. [1]

  $ make ARCH=arm arch/arm/lib/findbit.o
    CALL    scripts/checksyscalls.sh
    AS      arch/arm/lib/findbit.o

[1]: https://lore.kernel.org/linux-kbuild/YvUQOwL6lD4%2F5%2FU6@shell.armlinux.org.uk/

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2022-09-29 04:41:31 +09:00
Masahiro Yamada
9ec6ab6ee5 kbuild: use objtool-args-y to clean up objtool arguments
Based on Linus' patch. Refactor scripts/Makefile.vmlinux_o as well.

Link: https://lore.kernel.org/lkml/CAHk-=wgjTMQgiKzBZTmb=uWGDEQxDdyF1+qxBkODYciuNsmwnw@mail.gmail.com/
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-09-29 04:40:15 +09:00
Miguel Ojeda
2f7ab1267d Kbuild: add Rust support
Having most of the new files in place, we now enable Rust support
in the build system, including `Kconfig` entries related to Rust,
the Rust configuration printer and a few other bits.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Co-developed-by: Sven Van Asbroeck <thesven73@gmail.com>
Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Signed-off-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Co-developed-by: Douglas Su <d0u9.su@outlook.com>
Signed-off-by: Douglas Su <d0u9.su@outlook.com>
Co-developed-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
Signed-off-by: Dariusz Sosnowski <dsosnowski@dsosnowski.pl>
Co-developed-by: Antonio Terceiro <antonio.terceiro@linaro.org>
Signed-off-by: Antonio Terceiro <antonio.terceiro@linaro.org>
Co-developed-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Co-developed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-09-28 09:02:20 +02:00
Dmitry Baryshkov
d7c6ea024c kbuild: take into account DT_SCHEMA_FILES changes while checking dtbs
It is useful to be able to recheck dtbs files against a limited set of
DT schema files. This can be accomplished by using differnt
DT_SCHEMA_FILES argument values while rerunning make dtbs_check. However
for some reason if_changed_rule doesn't pick up the rule_dtc changes
(and doesn't retrigger the build).

Fix this by changing if_changed_rule to if_changed_dep and squashing DTC
and dt-validate into a single new command. Then if_changed_dep triggers
on DT_SCHEMA_FILES changes and reruns the build/check.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220915114422.79378-1-dmitry.baryshkov@linaro.org
Signed-off-by: Rob Herring <robh@kernel.org>
2022-09-27 10:09:45 -05:00
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
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
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
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
Masahiro Yamada
f97cf39991 kbuild: make multi_depend work with targets in subdirectory
Precisely speaking, when you get the stem of the path, you should use
$(patsubst $(obj)/%,%,...) instead of $(notdir ...).

I do not see this usecase, but if you create a composite object in a
subdirectory, the Makefile should look like this:

   obj-$(CONFIG_FOO) += dir/foo.o
   dir/foo-objs      := dir/foo1.o dir/foo2.o

The member objects should be assigned to dir/foo-objs instead of
foo-objs.

This syntax is more consistent with commit 54b8ae66ae ("kbuild:
change *FLAGS_<basetarget>.o to take the path relative to $(obj)").

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-05-08 03:16:59 +09:00
Masahiro Yamada
9eef99f7a3 kbuild: reuse suffix-search to refactor multi_depend
The complicated part of multi_depend is the same as suffix-search.

Reuse it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-05-08 03:16:58 +09:00
Linus Torvalds
b8321ed4a4 Merge tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

 - Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
   additional flags to be passed to user-space programs.

 - Fix missing fflush() bugs in Kconfig and fixdep

 - Fix a minor bug in the comment format of the .config file

 - Make kallsyms ignore llvm's local labels, .L*

 - Fix UAPI compile-test for cross-compiling with Clang

 - Extend the LLVM= syntax to support LLVM=<suffix> form for using a
   particular version of LLVm, and LLVM=<prefix> form for using custom
   LLVM in a particular directory path.

 - Clean up Makefiles

* tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Make $(LLVM) more flexible
  kbuild: add --target to correctly cross-compile UAPI headers with Clang
  fixdep: use fflush() and ferror() to ensure successful write to files
  arch: syscalls: simplify uapi/kapi directory creation
  usr/include: replace extra-y with always-y
  certs: simplify empty certs creation in certs/Makefile
  certs: include certs/signing_key.x509 unconditionally
  kallsyms: ignore all local labels prefixed by '.L'
  kconfig: fix missing '# end of' for empty menu
  kconfig: add fflush() before ferror() check
  kbuild: replace $(if A,A,B) with $(or A,B)
  kbuild: Add environment variables for userprogs flags
  kbuild: unify cmd_copy and cmd_shipped
2022-03-31 11:59:03 -07:00
Linus Torvalds
7001052160 Merge tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra:
 "Add support for Intel CET-IBT, available since Tigerlake (11th gen),
  which is a coarse grained, hardware based, forward edge
  Control-Flow-Integrity mechanism where any indirect CALL/JMP must
  target an ENDBR instruction or suffer #CP.

  Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation
  is limited to 2 instructions (and typically fewer) on branch targets
  not starting with ENDBR. CET-IBT also limits speculation of the next
  sequential instruction after the indirect CALL/JMP [1].

  CET-IBT is fundamentally incompatible with retpolines, but provides,
  as described above, speculation limits itself"

[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html

* tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
  kvm/emulate: Fix SETcc emulation for ENDBR
  x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0
  x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0
  kbuild: Fixup the IBT kbuild changes
  x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy
  x86: Remove toolchain check for X32 ABI capability
  x86/alternative: Use .ibt_endbr_seal to seal indirect calls
  objtool: Find unused ENDBR instructions
  objtool: Validate IBT assumptions
  objtool: Add IBT/ENDBR decoding
  objtool: Read the NOENDBR annotation
  x86: Annotate idtentry_df()
  x86,objtool: Move the ASM_REACHABLE annotation to objtool.h
  x86: Annotate call_on_stack()
  objtool: Rework ASM_REACHABLE
  x86: Mark __invalid_creds() __noreturn
  exit: Mark do_group_exit() __noreturn
  x86: Mark stop_this_cpu() __noreturn
  objtool: Ignore extra-symbol code
  objtool: Rename --duplicate to --lto
  ...
2022-03-27 10:17:23 -07:00
Peter Zijlstra
d31ed5d767 kbuild: Fixup the IBT kbuild changes
Masahiro-san deemed my kbuild changes to support whole module objtool
runs too terrible to live and gracefully provided an alternative.

Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/CAK7LNAQ2mYMnOKMQheVi+6byUFE3KEkjm1zcndNUfe0tORGvug@mail.gmail.com
2022-03-22 21:12:04 +01:00
Rob Herring
ef8795f3f1 dt-bindings: kbuild: Use DTB files for validation
Switch the DT validation to use DTB files directly instead of a DTS to
YAML conversion.

The original motivation for supporting validation on DTB files was to
enable running validation on a running system (e.g. 'dt-validate
/sys/firmware/fdt') or other cases where the original source DTS is not
available.

The YAML format was not without issues. Using DTBs with the schema type
information solves some of those problems. The YAML format relies on the
DTS source level information including bracketing of properties, size
directives, and phandle tags all of which are lost in a DTB file. While
standardizing the bracketing is a good thing, it does cause a lot of
extra warnings and churn to fix them.

Another issue has been signed types are not validated correctly as sign
information is not propagated to YAML. Using the schema type information
allows for proper handling of signed types. YAML also can't represent
the full range of 64-bit integers as numbers are stored as floats by
most/all parsers.

The DTB validation works by decoding property values using the type
information in the schemas themselves. The main corner case this does
not work for is matrix types where neither dimension is fixed. For
now, checking the dimensions in these cases are skipped.

Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220310160513.1708182-3-robh@kernel.org
2022-03-11 11:16:16 -06:00
Rob Herring
2783a7f56f dt-bindings: kbuild: Pass DT_SCHEMA_FILES to dt-validate
In preparation for supporting validation of DTB files, the full
processed schema will always be needed in order to extract type
information from it. Therefore, the processed schema containing only
what DT_SCHEMA_FILES specifies won't work. Instead, dt-validate has
gained an option, -l or --limit, to specify which schema(s) to use for
validation.

As the command line option is new, we the minimum dtschema version must be
updated.

Cc: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220310160513.1708182-2-robh@kernel.org
2022-03-11 09:30:27 -06:00
Masahiro Yamada
5c8166419a kbuild: replace $(if A,A,B) with $(or A,B)
$(or ...) is available since GNU Make 3.81, and useful to shorten the
code in some places.

Covert as follows:

  $(if A,A,B)  -->  $(or A,B)

This patch also converts:

  $(if A, A, B) --> $(or A, B)

Strictly speaking, the latter is not an equivalent conversion because
GNU Make keeps spaces after commas; if A is not empty, $(if A, A, B)
expands to " A", while $(or A, B) expands to "A".

Anyway, preceding spaces are not significant in the code hunks I touched.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2022-02-15 12:25:56 +09:00
Masahiro Yamada
a5575df580 kbuild: unify cmd_copy and cmd_shipped
cmd_copy and cmd_shipped have similar functionality. The difference is
that cmd_copy uses 'cp' while cmd_shipped 'cat'.

Unify them into cmd_copy because this macro name is more intuitive.

Going forward, cmd_copy will use 'cat' to avoid the permission issue.
I also thought of 'cp --no-preserve=mode' but this option is not
mentioned in the POSIX spec [1], so I am keeping the 'cat' command.

[1]: https://pubs.opengroup.org/onlinepubs/009695299/utilities/cp.html
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2022-02-14 10:37:32 +09:00
Linus Torvalds
fd6f57bfda Merge tag 'kbuild-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

 - Add new kconfig target 'make mod2noconfig', which will be useful to
   speed up the build and test iteration.

 - Raise the minimum supported version of LLVM to 11.0.0

 - Refactor certs/Makefile

 - Change the format of include/config/auto.conf to stop double-quoting
   string type CONFIG options.

 - Fix ARCH=sh builds in dash

 - Separate compression macros for general purposes (cmd_bzip2 etc.) and
   the ones for decompressors (cmd_bzip2_with_size etc.)

 - Misc Makefile cleanups

* tag 'kbuild-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  kbuild: add cmd_file_size
  arch: decompressor: remove useless vmlinux.bin.all-y
  kbuild: rename cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}
  kbuild: drop $(size_append) from cmd_zstd
  sh: rename suffix-y to suffix_y
  doc: kbuild: fix default in `imply` table
  microblaze: use built-in function to get CPU_{MAJOR,MINOR,REV}
  certs: move scripts/extract-cert to certs/
  kbuild: do not quote string values in include/config/auto.conf
  kbuild: do not include include/config/auto.conf from shell scripts
  certs: simplify $(srctree)/ handling and remove config_filename macro
  kbuild: stop using config_filename in scripts/Makefile.modsign
  certs: remove misleading comments about GCC PR
  certs: refactor file cleaning
  certs: remove unneeded -I$(srctree) option for system_certificates.o
  certs: unify duplicated cmd_extract_certs and improve the log
  certs: use $< and $@ to simplify the key generation rule
  kbuild: remove headers_check stub
  kbuild: move headers_check.pl to usr/include/
  certs: use if_changed to re-generate the key when the key type is changed
  ...
2022-01-19 11:15:19 +02:00
Masahiro Yamada
c4d7f40b25 kbuild: add cmd_file_size
Some architectures support self-extracting kernel, which embeds the
compressed vmlinux.

It has 4 byte data at the end so the decompressor can know the vmlinux
size beforehand.

GZIP natively has it in the trailer, but for the other compression
algorithms, the hand-crafted trailer is added.

It is unneeded to generate such _corrupted_ compressed files because
it is possible to pass the size data as a separate file.

For example, the assembly code:

     .incbin "compressed-vmlinux-with-size-data"

can be transformed to:

     .incbin "compressed-vmlinux"
     .incbin "size-data"

My hope is, after some reworks of the decompressors, the macros
cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}_with_size will go away.

This new macro, cmd_file_size, will be useful to generate a separate
size-data file.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
2022-01-14 02:57:43 +09:00
Masahiro Yamada
7ce7e984ab kbuild: rename cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}
GZIP-compressed files end with 4 byte data that represents the size
of the original input. The decompressors (the self-extracting kernel)
exploit it to know the vmlinux size beforehand. To mimic the GZIP's
trailer, Kbuild provides cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}.
Unfortunately these macros are used everywhere despite the appended
size data is only useful for the decompressors.

There is no guarantee that such hand-crafted trailers are safely ignored.
In fact, the kernel refuses compressed initramdfs with the garbage data.
That is why usr/Makefile overrides size_append to make it no-op.

To limit the use of such broken compressed files, this commit renames
the existing macros as follows:

  cmd_bzip2   --> cmd_bzip2_with_size
  cmd_lzma    --> cmd_lzma_with_size
  cmd_lzo     --> cmd_lzo_with_size
  cmd_lz4     --> cmd_lz4_with_size
  cmd_xzkern  --> cmd_xzkern_with_size
  cmd_zstd22  --> cmd_zstd22_with_size

To keep the decompressors working, I updated the following Makefiles
accordingly:

  arch/arm/boot/compressed/Makefile
  arch/h8300/boot/compressed/Makefile
  arch/mips/boot/compressed/Makefile
  arch/parisc/boot/compressed/Makefile
  arch/s390/boot/compressed/Makefile
  arch/sh/boot/compressed/Makefile
  arch/x86/boot/compressed/Makefile

I reused the current macro names for the normal usecases; they produce
the compressed data in the proper format.

I did not touch the following:

  arch/arc/boot/Makefile
  arch/arm64/boot/Makefile
  arch/csky/boot/Makefile
  arch/mips/boot/Makefile
  arch/riscv/boot/Makefile
  arch/sh/boot/Makefile
  kernel/Makefile

This means those Makefiles will stop appending the size data.

I dropped the 'override size_append' hack from usr/Makefile.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
2022-01-14 02:54:05 +09:00