linux-toradex.git/arch/riscv/kernel/Makefile, branch master

arch/riscv: add dual vdso creation logic and select vdso based on hw

2026-01-29T09:38:40+00:00

Shadow stack instructions are taken from the Zimop ISA extension,
which is mandated on RVA23. Any userspace with shadow stack
instructions in it will fault on hardware that doesn't have support
for Zimop.  Thus, a shadow stack-enabled userspace can't be run on
hardware that doesn't support Zimop.

It's not known how Linux userspace providers will respond to this kind
of binary fragmentation.  In order to keep kernel portable across
different hardware, 'arch/riscv/kernel/vdso_cfi' is created which has
Makefile logic to compile 'arch/riscv/kernel/vdso' sources with CFI
flags, and 'arch/riscv/kernel/vdso.c' is modified to select the
appropriate vdso depending on whether the underlying CPU implements
the Zimop extension. Since the offset of vdso symbols will change due
to having two different vdso binaries, there is added logic to include
a new generated vdso offset header and dynamically select the offset
(like for rt_sigreturn).

Signed-off-by: Deepak Gupta 
Acked-by: Charles Mirabile 
Tested-by: Andreas Korb  # QEMU, custom CVA6
Tested-by: Valentin Haudiquet 
Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-24-b55691eacf4f@rivosinc.com
[pjw@kernel.org: cleaned up patch description]
Signed-off-by: Paul Walmsley

riscv/mm: Implement map_shadow_stack() syscall

2026-01-29T09:15:20+00:00

As discussed extensively in the changelog for the addition of this
syscall on x86 ("x86/shstk: Introduce map_shadow_stack syscall") the
existing mmap() and madvise() syscalls do not map entirely well onto the
security requirements for shadow stack memory since they lead to windows
where memory is allocated but not yet protected or stacks which are not
properly and safely initialised. Instead a new syscall map_shadow_stack()
has been defined which allocates and initialises a shadow stack page.

This patch implements this syscall for riscv. riscv doesn't require
tokens to be setup by kernel because user mode can do that by
itself. However to provide compatibility and portability with other
architectues, user mode can specify token set flag.

Signed-off-by: Deepak Gupta 
Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-10-b55691eacf4f@rivosinc.com
Link: https://lore.kernel.org/linux-riscv/aXfRPJvoSsOW8AwM@debug.ba.rivosinc.com/
[pjw@kernel.org: added allocate_shadow_stack() fix per Deepak; fixed bug found by sparse]
Signed-off-by: Paul Walmsley

riscv: trace: fix snapshot deadlock with sbi ecall

2026-01-07T20:25:56+00:00

If sbi_ecall.c's functions are traceable,

echo "__sbi_ecall:snapshot" > /sys/kernel/tracing/set_ftrace_filter

may get the kernel into a deadlock.

(Functions in sbi_ecall.c are excluded from tracing if
CONFIG_RISCV_ALTERNATIVE_EARLY is set.)

__sbi_ecall triggers a snapshot of the ringbuffer. The snapshot code
raises an IPI interrupt, which results in another call to __sbi_ecall
and another snapshot...

All it takes to get into this endless loop is one initial __sbi_ecall.
On RISC-V systems without SSTC extension, the clock events in
timer-riscv.c issue periodic sbi ecalls, making the problem easy to
trigger.

Always exclude the sbi_ecall.c functions from tracing to fix the
potential deadlock.

sbi ecalls can easiliy be logged via trace events, excluding ecall
functions from function tracing is not a big limitation.

Signed-off-by: Martin Kaiser 
Link: https://patch.msgid.link/20251223135043.1336524-1-martin@kaiser.cx
Signed-off-by: Paul Walmsley

kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI

2025-09-24T21:29:14+00:00

The kernel's CFI implementation uses the KCFI ABI specifically, and is
not strictly tied to a particular compiler. In preparation for GCC
supporting KCFI, rename CONFIG_CFI_CLANG to CONFIG_CFI (along with
associated options).

Use new "transitional" Kconfig option for old CONFIG_CFI_CLANG that will
enable CONFIG_CFI during olddefconfig.

Reviewed-by: Linus Walleij 
Reviewed-by: Nathan Chancellor 
Link: https://lore.kernel.org/r/20250923213422.1105654-3-kees@kernel.org
Signed-off-by: Kees Cook

Merge tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2025-06-07T17:05:35+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Add support for the EXPORT_SYMBOL_GPL_FOR_MODULES() macro, which
   exports a symbol only to specified modules

 - Improve ABI handling in gendwarfksyms

 - Forcibly link lib-y objects to vmlinux even if CONFIG_MODULES=n

 - Add checkers for redundant or missing  inclusion

 - Deprecate the extra-y syntax

 - Fix a genksyms bug when including enum constants from *.symref files

* tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (28 commits)
  genksyms: Fix enum consts from a reference affecting new values
  arch: use always-$(KBUILD_BUILTIN) for vmlinux.lds
  kbuild: set y instead of 1 to KBUILD_{BUILTIN,MODULES}
  efi/libstub: use 'targets' instead of extra-y in Makefile
  module: make __mod_device_table__* symbols static
  scripts/misc-check: check unnecessary #include  when W=1
  scripts/misc-check: check missing #include  when W=1
  scripts/misc-check: add double-quotes to satisfy shellcheck
  kbuild: move W=1 check for scripts/misc-check to top-level Makefile
  scripts/tags.sh: allow to use alternative ctags implementation
  kconfig: introduce menu type enum
  docs: symbol-namespaces: fix reST warning with literal block
  kbuild: link lib-y objects to vmlinux forcibly even when CONFIG_MODULES=n
  tinyconfig: enable CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
  docs/core-api/symbol-namespaces: drop table of contents and section numbering
  modpost: check forbidden MODULE_IMPORT_NS("module:") at compile time
  kbuild: move kbuild syntax processing to scripts/Makefile.build
  Makefile: remove dependency on archscripts for header installation
  Documentation/kbuild: Add new gendwarfksyms kABI rules
  Documentation/kbuild: Drop section numbers
  ...

arch: use always-$(KBUILD_BUILTIN) for vmlinux.lds

2025-06-07T05:38:07+00:00

The extra-y syntax is deprecated. Instead, use always-$(KBUILD_BUILTIN),
which behaves equivalently.

Signed-off-by: Masahiro Yamada 
Acked-by: Johannes Berg 
Reviewed-by: Nicolas Schier

Merge tag 'riscv-mw2-6.16-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/alexghiti/linux into for-next

2025-06-05T21:03:16+00:00

riscv patches for 6.16-rc1, part 2

* Performance improvements
  - Add support for vdso getrandom
  - Implement raid6 calculations using vectors
  - Introduce svinval tlb invalidation

* Cleanup
  - A bunch of deduplication of the macros we use for manipulating instructions

* Misc
  - Introduce a kunit test for kprobes
  - Add support for mseal as riscv fits the requirements (thanks to Lorenzo for making sure of that :))

[Palmer: There was a rebase between part 1 and part 2, so I've had to do
some more git surgery here... at least two rounds of surgery...]

* alex-pr-2: (866 commits)
  RISC-V: vDSO: Wire up getrandom() vDSO implementation
  riscv: enable mseal sysmap for RV64
  raid6: Add RISC-V SIMD syndrome and recovery calculations
  riscv: mm: Add support for Svinval extension
  riscv: Add kprobes KUnit test
  riscv: kprobes: Remove duplication of RV_EXTRACT_ITYPE_IMM
  riscv: kprobes: Remove duplication of RV_EXTRACT_UTYPE_IMM
  riscv: kprobes: Remove duplication of RV_EXTRACT_RD_REG
  riscv: kprobes: Remove duplication of RVC_EXTRACT_BTYPE_IMM
  riscv: kprobes: Remove duplication of RVC_EXTRACT_C2_RS1_REG
  riscv: kproves: Remove duplication of RVC_EXTRACT_JTYPE_IMM
  riscv: kprobes: Remove duplication of RV_EXTRACT_BTYPE_IMM
  riscv: kprobes: Remove duplication of RV_EXTRACT_RS1_REG
  riscv: kprobes: Remove duplication of RV_EXTRACT_JTYPE_IMM
  riscv: kprobes: Move branch_funct3 to insn.h
  riscv: kprobes: Move branch_rs2_idx to insn.h
  Linux 6.15-rc6
  Input: xpad - fix xpad_device sorting
  Input: xpad - add support for several more controllers
  Input: xpad - fix Share button on Xbox One controllers
  ...

riscv: kexec_file: Support loading Image binary file

2025-06-05T18:09:34+00:00

This patch creates image_kexec_ops to load Image binary file
for kexec_file_load() syscall.

Signed-off-by: Song Shuai 
Signed-off-by: Björn Töpel 
Link: https://lore.kernel.org/r/20250409193004.643839-3-bjorn@kernel.org
Signed-off-by: Alexandre Ghiti 
Signed-off-by: Palmer Dabbelt

riscv: kexec_file: Split the loading of kernel and others

2025-06-05T18:09:33+00:00

This is the preparative patch for kexec_file_load Image support.

It separates the elf_kexec_load() as two parts:
- the first part loads the vmlinux (or Image)
- the second part loads other segments (e.g. initrd,fdt,purgatory)

And the second part is exported as the load_extra_segments() function
which would be used in both kexec-elf.c and kexec-image.c.

No functional change intended.

Signed-off-by: Song Shuai 
Signed-off-by: Björn Töpel 
Link: https://lore.kernel.org/r/20250409193004.643839-2-bjorn@kernel.org
Signed-off-by: Alexandre Ghiti 
Signed-off-by: Palmer Dabbelt

Fix mis-uses of 'cc-option' for warning disablement

2025-04-23T17:08:29+00:00

This was triggered by one of my mis-uses causing odd build warnings on
sparc in linux-next, but while figuring out why the "obviously correct"
use of cc-option caused such odd breakage, I found eight other cases of
the same thing in the tree.

The root cause is that 'cc-option' doesn't work for checking negative
warning options (ie things like '-Wno-stringop-overflow') because gcc
will silently accept options it doesn't recognize, and so 'cc-option'
ends up thinking they are perfectly fine.

And it all works, until you have a situation where _another_ warning is
emitted.  At that point the compiler will go "Hmm, maybe the user
intended to disable this warning but used that wrong option that I
didn't recognize", and generate a warning for the unrecognized negative
option.

Which explains why we have several cases of this in the tree: the
'cc-option' test really doesn't work for this situation, but most of the
time it simply doesn't matter that ity doesn't work.

The reason my recently added case caused problems on sparc was pointed
out by Thomas Weißschuh: the sparc build had a previous explicit warning
that then triggered the new one.

I think the best fix for this would be to make 'cc-option' a bit smarter
about this sitation, possibly by adding an intentional warning to the
test case that then triggers the unrecognized option warning reliably.

But the short-term fix is to replace 'cc-option' with an existing helper
designed for this exact case: 'cc-disable-warning', which picks the
negative warning but uses the positive form for testing the compiler
support.

Reported-by: Stephen Rothwell 
Link: https://lore.kernel.org/all/20250422204718.0b4e3f81@canb.auug.org.au/
Explained-by: Thomas Weißschuh 
Signed-off-by: Linus Torvalds