linux.git/arch/riscv/kernel, branch v5.4.64

RISC-V: Don't allow write+exec only page mapping request in mmap

2020-06-30T19:37:06+00:00

[ Upstream commit e0d17c842c0f824fd4df9f4688709fc6907201e1 ]

As per the table 4.4 of version "20190608-Priv-MSU-Ratified" of the
RISC-V instruction set manual[0], the PTE permission bit combination of
"write+exec only" is reserved for future use. Hence, don't allow such
mapping request in mmap call.

An issue is been reported by David Abdurachmanov, that while running
stress-ng with "sysbadaddr" argument, RCU stalls are observed on RISC-V
specific kernel.

This issue arises when the stress-sysbadaddr request for pages with
"write+exec only" permission bits and then passes the address obtain
from this mmap call to various system call. For the riscv kernel, the
mmap call should fail for this particular combination of permission bits
since it's not valid.

[0]: http://dabbelt.com/~palmer/keep/riscv-isa-manual/riscv-privileged-20190608-1.pdf

Signed-off-by: Yash Shah 
Reported-by: David Abdurachmanov 
[Palmer: Refer to the latest ISA specification at the only link I could
find, and update the terminology.]
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

riscv: stacktrace: Fix undefined reference to `walk_stackframe'

2020-06-03T06:21:13+00:00

[ Upstream commit 0502bee37cdef755d63eee60236562e5605e2480 ]

Drop static declaration to fix following build error if FRAME_POINTER disabled,
  riscv64-linux-ld: arch/riscv/kernel/perf_callchain.o: in function `.L0':
  perf_callchain.c:(.text+0x2b8): undefined reference to `walk_stackframe'

Reported-by: Hulk Robot 
Signed-off-by: Kefeng Wang 
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

riscv: fix vdso build with lld

2020-05-20T06:20:13+00:00

[ Upstream commit 3c1918c8f54166598195d938564072664a8275b1 ]

When building with the LLVM linker this error occurrs:
    LD      arch/riscv/kernel/vdso/vdso-syms.o
  ld.lld: error: no input files

This happens because the lld treats -R as an alias to -rpath, as opposed
to ld where -R means --just-symbols.

Use the long option name for compatibility between the two.

Link: https://github.com/ClangBuiltLinux/linux/issues/805
Reported-by: Dmitry Golovin 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Ilie Halip 
Reviewed-by: Fangrui Song 
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

riscv: avoid the PIC offset of static percpu data in module beyond 2G limits

2020-03-25T07:25:48+00:00

[ Upstream commit 0cff8bff7af886af0923d5c91776cd51603e531f ]

The compiler uses the PIC-relative method to access static variables
instead of GOT when the code model is PIC. Therefore, the limitation of
the access range from the instruction to the symbol address is +-2GB.
Under this circumstance, the kernel cannot load a kernel module if this
module has static per-CPU symbols declared by DEFINE_PER_CPU(). The reason
is that kernel relocates the .data..percpu section of the kernel module to
the end of kernel's .data..percpu. Hence, the distance between the per-CPU
symbols and the instruction will exceed the 2GB limits. To solve this
problem, the kernel should place the loaded module in the memory area
[&_end-2G, VMALLOC_END].

Signed-off-by: Vincent Chen 
Suggested-by: Alexandre Ghiti 
Suggested-by: Anup Patel 
Tested-by: Alexandre Ghiti 
Tested-by: Carlos de Paula 
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

riscv: delete temporary files

2020-02-05T21:22:47+00:00

[ Upstream commit 95f4d9cced96afa9c69b3da8e79e96102c84fc60 ]

Temporary files used in the VDSO build process linger on even after make
mrproper: vdso-dummy.o.tmp, vdso.so.dbg.tmp.

Delete them once they're no longer needed.

Signed-off-by: Ilie Halip 
Signed-off-by: Paul Walmsley 
Signed-off-by: Sasha Levin

riscv: Implement copy_thread_tls

2020-01-14T19:08:34+00:00

commit 20bda4ed62f507ed72e30e817b43c65fdba60be7 upstream.

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras 
Cc: linux-riscv@lists.infradead.org
Cc:  # 5.3.x
Link: https://lore.kernel.org/r/20200102172413.654385-6-amanieu@gmail.com
Signed-off-by: Christian Brauner 
Signed-off-by: Greg Kroah-Hartman

riscv: ftrace: correct the condition logic in function graph tracer

2020-01-09T09:19:59+00:00

commit 1d8f65798240b6577d8c44d20c8ea8f1d429e495 upstream.

The condition should be logical NOT to assign the hook address to parent
address. Because the return value 0 of function_graph_enter upon
success.

Fixes: e949b6db51dc (riscv/function_graph: Simplify with function_graph_enter())
Signed-off-by: Zong Li 
Reviewed-by: Steven Rostedt (VMware) 
Cc: stable@vger.kernel.org
Signed-off-by: Paul Walmsley 
Signed-off-by: Greg Kroah-Hartman

riscv: for C functions called only from assembly, mark with __visible

2019-10-28T07:46:02+00:00

Rather than adding prototypes for C functions called only by assembly
code, mark them as __visible.  This avoids adding prototypes that will
never be used by the callers.  Resolves the following sparse warnings:

arch/riscv/kernel/irq.c:27:29: warning: symbol 'do_IRQ' was not declared. Should it be static?
arch/riscv/kernel/ptrace.c:151:6: warning: symbol 'do_syscall_trace_enter' was not declared. Should it be static?
arch/riscv/kernel/ptrace.c:165:6: warning: symbol 'do_syscall_trace_exit' was not declared. Should it be static?
arch/riscv/kernel/signal.c:295:17: warning: symbol 'do_notify_resume' was not declared. Should it be static?
arch/riscv/kernel/traps.c:92:1: warning: symbol 'do_trap_unknown' was not declared. Should it be static?
arch/riscv/kernel/traps.c:94:1: warning: symbol 'do_trap_insn_misaligned' was not declared. Should it be static?
arch/riscv/kernel/traps.c:96:1: warning: symbol 'do_trap_insn_fault' was not declared. Should it be static?
arch/riscv/kernel/traps.c:98:1: warning: symbol 'do_trap_insn_illegal' was not declared. Should it be static?
arch/riscv/kernel/traps.c:100:1: warning: symbol 'do_trap_load_misaligned' was not declared. Should it be static?
arch/riscv/kernel/traps.c:102:1: warning: symbol 'do_trap_load_fault' was not declared. Should it be static?
arch/riscv/kernel/traps.c:104:1: warning: symbol 'do_trap_store_misaligned' was not declared. Should it be static?
arch/riscv/kernel/traps.c:106:1: warning: symbol 'do_trap_store_fault' was not declared. Should it be static?
arch/riscv/kernel/traps.c:108:1: warning: symbol 'do_trap_ecall_u' was not declared. Should it be static?
arch/riscv/kernel/traps.c:110:1: warning: symbol 'do_trap_ecall_s' was not declared. Should it be static?
arch/riscv/kernel/traps.c:112:1: warning: symbol 'do_trap_ecall_m' was not declared. Should it be static?
arch/riscv/kernel/traps.c:124:17: warning: symbol 'do_trap_break' was not declared. Should it be static?
arch/riscv/kernel/smpboot.c:136:24: warning: symbol 'smp_callin' was not declared. Should it be static?

Based on a suggestion from Luc Van Oostenryck.

This version includes changes based on feedback from Christoph Hellwig
.

Signed-off-by: Paul Walmsley 
Cc: Luc Van Oostenryck 
Reviewed-by: Christoph Hellwig  # for do_syscall_trace_*

riscv: fp: add missing __user pointer annotations

2019-10-28T07:46:01+00:00

The __user annotations were removed from the {save,restore}_fp_state()
function signatures by commit 007f5c358957 ("Refactor FPU code in
signal setup/return procedures"), but should be present, and sparse
warns when they are not applied.  Add them back in.

This change should have no functional impact.

Signed-off-by: Paul Walmsley 
Fixes: 007f5c358957 ("Refactor FPU code in signal setup/return procedures")
Cc: Alan Kao 
Reviewed-by: Christoph Hellwig

riscv: add missing header file includes

2019-10-28T07:46:01+00:00

sparse identifies several missing prototypes caused by missing
preprocessor include directives:

arch/riscv/kernel/cpufeature.c:16:6: warning: symbol 'has_fpu' was not declared. Should it be static?
arch/riscv/kernel/process.c:26:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static?
arch/riscv/kernel/reset.c:15:6: warning: symbol 'pm_power_off' was not declared. Should it be static?
arch/riscv/kernel/syscall_table.c:15:6: warning: symbol 'sys_call_table' was not declared. Should it be static?
arch/riscv/kernel/traps.c:149:13: warning: symbol 'trap_init' was not declared. Should it be static?
arch/riscv/kernel/vdso.c:54:5: warning: symbol 'arch_setup_additional_pages' was not declared. Should it be static?
arch/riscv/kernel/smp.c:64:6: warning: symbol 'arch_match_cpu_phys_id' was not declared. Should it be static?
arch/riscv/kernel/module-sections.c:89:5: warning: symbol 'module_frob_arch_sections' was not declared. Should it be static?
arch/riscv/mm/context.c:42:6: warning: symbol 'switch_mm' was not declared. Should it be static?

Fix by including the appropriate header files in the appropriate
source files.

This patch should have no functional impact.

Signed-off-by: Paul Walmsley 
Reviewed-by: Christoph Hellwig