linux.git/arch/riscv/kernel, branch v6.16

riscv: traps_misaligned: properly sign extend value in misaligned load handler

2025-07-16T16:05:39+00:00

Add missing cast to signed long.

Signed-off-by: Andreas Schwab 
Fixes: 956d705dd279 ("riscv: Unaligned load/store handling for M_MODE")
Tested-by: Clément Léger 
Link: https://lore.kernel.org/r/mvmikk0goil.fsf@suse.de
Signed-off-by: Palmer Dabbelt

riscv: Enable interrupt during exception handling

2025-07-16T16:05:26+00:00

force_sig_fault() takes a spinlock, which is a sleeping lock with
CONFIG_PREEMPT_RT=y. However, exception handling calls force_sig_fault()
with interrupt disabled, causing a sleeping in atomic context warning.

This can be reproduced using userspace programs such as:
    int main() { asm ("ebreak"); }
or
    int main() { asm ("unimp"); }

There is no reason that interrupt must be disabled while handling
exceptions from userspace.

Enable interrupt while handling user exceptions. This also has the added
benefit of avoiding unnecessary delays in interrupt handling.

Fixes: f0bddf50586d ("riscv: entry: Convert to generic entry")
Suggested-by: Sebastian Andrzej Siewior 
Signed-off-by: Nam Cao 
Reviewed-by: Alexandre Ghiti 
Link: https://lore.kernel.org/r/20250625085630.3649485-1-namcao@linutronix.de
Signed-off-by: Palmer Dabbelt

riscv: ftrace: Properly acquire text_mutex to fix a race condition

2025-07-16T15:21:47+00:00

As reported by lockdep, some patching was done without acquiring
text_mutex, so there could be a race when mapping the page to patch
since we use the same fixmap entry.

Reported-by: Han Gao 
Reported-by: Vivian Wang 
Reported-by: Yao Zi 
Closes: https://lore.kernel.org/linux-riscv/aGODMpq7TGINddzM@pie.lan/
Tested-by: Yao Zi 
Tested-by: Han Gao 
Reviewed-by: Masami Hiramatsu (Google) 
Signed-off-by: Alexandre Ghiti 
Link: https://lore.kernel.org/r/20250711-alex-fixes-v2-1-d85a5438da6c@rivosinc.com
Signed-off-by: Palmer Dabbelt

riscv: cpu_ops_sbi: Use static array for boot_data

2025-06-30T06:58:11+00:00

Since commit 6b9f29b81b15 ("riscv: Enable pcpu page first chunk
allocator"), if NUMA is enabled, the page percpu allocator may be used
on very sparse configurations, or when requested on boot with
percpu_alloc=page.

In that case, percpu data gets put in the vmalloc area. However,
sbi_hsm_hart_start() needs the physical address of a sbi_hart_boot_data,
and simply assumes that __pa() would work. This causes the just started
hart to immediately access an invalid address and hang.

Fortunately, struct sbi_hart_boot_data is not too large, so we can
simply allocate an array for boot_data statically, putting it in the
kernel image.

This fixes NUMA=y SMP boot on Sophgo SG2042.

To reproduce on QEMU: Set CONFIG_NUMA=y and CONFIG_DEBUG_VIRTUAL=y, then
run with:

  qemu-system-riscv64 -M virt -smp 2 -nographic \
    -kernel arch/riscv/boot/Image \
    -append "percpu_alloc=page"

Kernel output:

[    0.000000] Booting Linux on hartid 0
[    0.000000] Linux version 6.16.0-rc1 (dram@sakuya) (riscv64-unknown-linux-gnu-gcc (GCC) 14.2.1 20250322, GNU ld (GNU Binutils) 2.44) #11 SMP Tue Jun 24 14:56:22 CST 2025
...
[    0.000000] percpu: 28 4K pages/cpu s85784 r8192 d20712
...
[    0.083192] smp: Bringing up secondary CPUs ...
[    0.086722] ------------[ cut here ]------------
[    0.086849] virt_to_phys used for non-linear address: (____ptrval____) (0xff2000000001d080)
[    0.088001] WARNING: CPU: 0 PID: 1 at arch/riscv/mm/physaddr.c:14 __virt_to_phys+0xae/0xe8
[    0.088376] Modules linked in:
[    0.088656] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.16.0-rc1 #11 NONE
[    0.088833] Hardware name: riscv-virtio,qemu (DT)
[    0.088948] epc : __virt_to_phys+0xae/0xe8
[    0.089001]  ra : __virt_to_phys+0xae/0xe8
[    0.089037] epc : ffffffff80021eaa ra : ffffffff80021eaa sp : ff2000000004bbc0
[    0.089057]  gp : ffffffff817f49c0 tp : ff60000001d60000 t0 : 5f6f745f74726976
[    0.089076]  t1 : 0000000000000076 t2 : 705f6f745f747269 s0 : ff2000000004bbe0
[    0.089095]  s1 : ff2000000001d080 a0 : 0000000000000000 a1 : 0000000000000000
[    0.089113]  a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000
[    0.089131]  a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000000000
[    0.089155]  s2 : ffffffff8130dc00 s3 : 0000000000000001 s4 : 0000000000000001
[    0.089174]  s5 : ffffffff8185eff8 s6 : ff2000007f1eb000 s7 : ffffffff8002a2ec
[    0.089193]  s8 : 0000000000000001 s9 : 0000000000000001 s10: 0000000000000000
[    0.089211]  s11: 0000000000000000 t3 : ffffffff8180a9f7 t4 : ffffffff8180a9f7
[    0.089960]  t5 : ffffffff8180a9f8 t6 : ff2000000004b9d8
[    0.089984] status: 0000000200000120 badaddr: ffffffff80021eaa cause: 0000000000000003
[    0.090101] [] __virt_to_phys+0xae/0xe8
[    0.090228] [] sbi_cpu_start+0x6e/0xe8
[    0.090247] [] __cpu_up+0x1e/0x8c
[    0.090260] [] bringup_cpu+0x42/0x258
[    0.090277] [] cpuhp_invoke_callback+0xe0/0x40c
[    0.090292] [] __cpuhp_invoke_callback_range+0x68/0xfc
[    0.090320] [] _cpu_up+0x11a/0x244
[    0.090334] [] cpu_up+0x52/0x90
[    0.090384] [] bringup_nonboot_cpus+0x78/0x118
[    0.090411] [] smp_init+0x34/0xb8
[    0.090425] [] kernel_init_freeable+0x148/0x2e4
[    0.090442] [] kernel_init+0x1e/0x14c
[    0.090455] [] ret_from_fork_kernel+0xe/0xf0
[    0.090471] [] ret_from_fork_kernel_asm+0x16/0x18
[    0.090560] ---[ end trace 0000000000000000 ]---
[    1.179875] CPU1: failed to come online
[    1.190324] smp: Brought up 1 node, 1 CPU

Cc: stable@vger.kernel.org
Reported-by: Han Gao 
Fixes: 6b9f29b81b15 ("riscv: Enable pcpu page first chunk allocator")
Reviewed-by: Alexandre Ghiti 
Tested-by: Alexandre Ghiti 
Signed-off-by: Vivian Wang 
Link: https://lore.kernel.org/r/20250624-riscv-hsm-boot-data-array-v1-1-50b5eeafbe61@iscas.ac.cn
Signed-off-by: Alexandre Ghiti

riscv: export boot_cpu_hartid

2025-06-23T23:30:05+00:00

The mailbox controller driver for the Microchip Inter-processor
Communication can be built as a module. It uses cpuid_to_hartid_map and
commit 4783ce32b080 ("riscv: export __cpuid_to_hartid_map") enables that
to work for SMP. However, cpuid_to_hartid_map uses boot_cpu_hartid on
non-SMP kernels and this driver can be useful in such configurations[1].

Export boot_cpu_hartid so the driver can be built as a module on non-SMP
kernels as well.

Link: https://lore.kernel.org/lkml/20250617-confess-reimburse-876101e099cb@spud/ [1]
Cc: stable@vger.kernel.org
Fixes: e4b1d67e7141 ("mailbox: add Microchip IPC support")
Signed-off-by: Klara Modin 
Acked-by: Conor Dooley 
Link: https://lore.kernel.org/r/20250617125847.23829-1-klarasmodin@gmail.com
Signed-off-by: Palmer Dabbelt

riscv: Fix sparse warning in vendor_extensions/sifive.c

2025-06-23T22:57:59+00:00

sparse reports the following warning:

arch/riscv/kernel/vendor_extensions/sifive.c:11:33: sparse: sparse: symbol 'riscv_isa_vendor_ext_sifive' was not declared. Should it be static?

So as this struct is only used in this file, make it static.

Fixes: 2d147d77ae6e ("riscv: Add SiFive xsfvqmaccdod and xsfvqmaccqoq vendor extensions")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202505072100.TZlEp8h1-lkp@intel.com/
Signed-off-by: Alexandre Ghiti 
Link: https://lore.kernel.org/r/20250620-dev-alex-fix_sparse_sifive_v1-v1-1-efa3a6f93846@rivosinc.com
Signed-off-by: Palmer Dabbelt

Revert "riscv: misaligned: fix sleeping function called during misaligned access handling"

2025-06-23T22:38:09+00:00

This reverts commit 61a74ad25462 ("riscv: misaligned: fix sleeping function
called during misaligned access handling"). The commit addresses a sleeping
in atomic context problem, but it is not the correct fix as explained by
Clément:

"Using nofault would lead to failure to read from user memory that is paged
out for instance. This is not really acceptable, we should handle user
misaligned access even at an address that would generate a page fault."

This bug has been properly fixed by commit 453805f0a28f ("riscv:
misaligned: enable IRQs while handling misaligned accesses").

Revert this improper fix.

Link: https://lore.kernel.org/linux-riscv/b779beed-e44e-4a5e-9551-4647682b0d21@rivosinc.com/
Signed-off-by: Nam Cao 
Cc: stable@vger.kernel.org
Reviewed-by: Clément Léger 
Reviewed-by: Alexandre Ghiti 
Fixes: 61a74ad25462 ("riscv: misaligned: fix sleeping function called during misaligned access handling")
Link: https://lore.kernel.org/r/20250620110939.1642735-1-namcao@linutronix.de
Signed-off-by: Palmer Dabbelt

riscv: vdso: Exclude .rodata from the PT_DYNAMIC segment

2025-06-10T20:06:48+00:00

.rodata is implicitly included in the PT_DYNAMIC segment due to
inheriting the segment of the preceding .dynamic section (in both GNU ld
and LLD).  When the .rodata section's size is not a multiple of 16
bytes on riscv64, llvm-readelf will report a "PT_DYNAMIC dynamic table
is invalid" warning.  Note: in the presence of the .dynamic section, GNU
readelf and llvm-readelf's -d option decodes the dynamic section using
the section.

This issue arose after commit 8f8c1ff879fab60f80f3a7aec3000f47e5b03ba9
("riscv: vdso.lds.S: remove hardcoded 0x800 .text start addr"), which
placed .rodata directly after .dynamic by removing .eh_frame.

This patch resolves the implicit inclusion into PT_DYNAMIC by explicitly
specifying the :text output section phdr.

Reported-by: Nathan Chancellor 
Closes: https://github.com/ClangBuiltLinux/linux/issues/2093
Signed-off-by: Fangrui Song 
Tested-by: Nathan Chancellor 
Link: https://lore.kernel.org/r/20250602-riscv-vdso-v1-1-0620cf63cff0@maskray.me
Signed-off-by: Palmer Dabbelt

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