linux-stable.git/arch/riscv/kernel, branch linux-6.3.y

riscv: uprobes: Restore thread.bad_cause

2023-07-11T17:39:48+00:00

[ Upstream commit 58b1294dd1d65bb62f08dddbf418f954210c2057 ]

thread.bad_cause is saved in arch_uprobe_pre_xol(), it should be restored
in arch_uprobe_{post,abort}_xol() accordingly, otherwise the save operation
is meaningless, this change is similar with x86 and powerpc.

Signed-off-by: Tiezhu Yang 
Acked-by: Oleg Nesterov 
Reviewed-by: Guo Ren 
Fixes: 74784081aac8 ("riscv: Add uprobes supported")
Link: https://lore.kernel.org/r/1682214146-3756-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

riscv: vmlinux.lds.S: Explicitly handle '.got' section

2023-06-09T08:48:25+00:00

This patch is for linux-6.3.y only, it has no direct mainline
equivalent.

LLVM 17 will now use the GOT for extern weak symbols when using the
medany model, which causes a linker orphan section warning on
linux-6.3.y:

  ld.lld: warning: :(.got) is being placed in '.got'

This is not an issue in mainline because handling of the .got section
was added by commit 39b33072941f ("riscv: Introduce CONFIG_RELOCATABLE")
and further extended by commit 26e7aacb83df ("riscv: Allow to downgrade
paging mode from the command line") in 6.4-rc1. Neither of these changes
are suitable for stable, so add explicit handling of the .got section in
a standalone change to align 6.3 and mainline, which addresses the
warning.

This is only an issue for 6.3 because commit f4b71bff8d85 ("riscv:
select ARCH_WANT_LD_ORPHAN_WARN for !XIP_KERNEL") landed in 6.3-rc1, so
earlier releases will not see this warning because it will not be
enabled.

Closes: https://github.com/ClangBuiltLinux/linux/issues/1865
Link: https://github.com/llvm/llvm-project/commit/a178ba9fbd0a27057dc2fa4cb53c76caa013caac
Signed-off-by: Nathan Chancellor 
Reviewed-by: Conor Dooley 
Signed-off-by: Greg Kroah-Hartman

rethook, fprobe: do not trace rethook related functions

2023-05-24T16:30:24+00:00

commit 571a2a50a8fc546145ffd3bf673547e9fe128ed2 upstream.

These functions are already marked as NOKPROBE to prevent recursion and
we have the same reason to blacklist them if rethook is used with fprobe,
since they are beyond the recursion-free region ftrace can guard.

Link: https://lore.kernel.org/all/20230517034510.15639-5-zegao@tencent.com/

Fixes: f3a112c0c40d ("x86,rethook,kprobes: Replace kretprobe with rethook on x86")
Signed-off-by: Ze Gao 
Reviewed-by: Steven Rostedt (Google) 
Acked-by: Masami Hiramatsu (Google) 
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Greg Kroah-Hartman

riscv: Fix EFI stub usage of KASAN instrumented strcmp function

2023-05-24T16:30:10+00:00

[ Upstream commit 617955ca6e275c4dd0dcf5316fca7fc04a8f2fe6 ]

The EFI stub must not use any KASAN instrumented code as the kernel
proper did not initialize the thread pointer and the mapping for the
KASAN shadow region.

Avoid using the generic strcmp function, instead use the one in
drivers/firmware/efi/libstub/string.c.

Signed-off-by: Alexandre Ghiti 
Acked-by: Ard Biesheuvel 
Reviewed-by: Atish Patra 
Link: https://lore.kernel.org/r/20230203075232.274282-5-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

riscv: compat_syscall_table: Fixup compile warning

2023-05-17T12:01:42+00:00

[ Upstream commit f9c4bbddece7eff1155c70d48e3c9c2a01b9d778 ]

../arch/riscv/kernel/compat_syscall_table.c:12:41: warning: initialized
field overwritten [-Woverride-init]
   12 | #define __SYSCALL(nr, call)      [nr] = (call),
      |                                         ^
../include/uapi/asm-generic/unistd.h:567:1: note: in expansion of macro
'__SYSCALL'
  567 | __SYSCALL(__NR_semget, sys_semget)

Fixes: 59c10c52f573 ("riscv: compat: syscall: Add compat_sys_call_table implementation")
Reviewed-by: Conor Dooley 
Reported-by: kernel test robot 
Tested-by: Jisheng Zhang 
Signed-off-by: Guo Ren 
Signed-off-by: Guo Ren 
Signed-off-by: Drew Fustini 
Link: https://lore.kernel.org/r/20230501223353.2833899-1-dfustini@baylibre.com
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Sasha Levin

RISC-V: Align SBI probe implementation with spec

2023-05-11T14:16:53+00:00

commit 41cad8284d5e6bf1d49d3c10a6b52ee1ae866a20 upstream.

sbi_probe_extension() is specified with "Returns 0 if the given SBI
extension ID (EID) is not available, or 1 if it is available unless
defined as any other non-zero value by the implementation."
Additionally, sbiret.value is a long. Fix the implementation to
ensure any nonzero long value is considered a success, rather
than only positive int values.

Fixes: b9dcd9e41587 ("RISC-V: Add basic support for SBI v0.2")
Signed-off-by: Andrew Jones 
Reviewed-by: Conor Dooley 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230427163626.101042-1-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Greg Kroah-Hartman

riscv: Do not set initial_boot_params to the linear address of the dtb

2023-04-14T01:14:33+00:00

early_init_dt_verify() is already called in parse_dtb() and since the dtb
address does not change anymore (it is now in the fixmap region), no need
to reset initial_boot_params by calling early_init_dt_verify() again.

Signed-off-by: Alexandre Ghiti 
Link: https://lore.kernel.org/r/20230329081932.79831-3-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt

riscv: Move early dtb mapping into the fixmap region

2023-04-14T01:14:26+00:00

riscv establishes 2 virtual mappings:

- early_pg_dir maps the kernel which allows to discover the system
  memory
- swapper_pg_dir installs the final mapping (linear mapping included)

We used to map the dtb in early_pg_dir using DTB_EARLY_BASE_VA, and this
mapping was not carried over in swapper_pg_dir. It happens that
early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is
setup otherwise we could allocate reserved memory defined in the dtb.
And this function initializes reserved_mem variable with addresses that
lie in the early_pg_dir dtb mapping: when those addresses are reused
with swapper_pg_dir, this mapping does not exist and then we trap.

The previous "fix" was incorrect as early_init_fdt_scan_reserved_mem()
must be called before swapper_pg_dir is set up otherwise we could
allocate in reserved memory defined in the dtb.

So move the dtb mapping in the fixmap region which is established in
early_pg_dir and handed over to swapper_pg_dir.

Fixes: 922b0375fc93 ("riscv: Fix memblock reservation for device tree blob")
Fixes: 8f3a2b4a96dc ("RISC-V: Move DT mapping outof fixmap")
Fixes: 50e63dd8ed92 ("riscv: fix reserved memory setup")
Reported-by: Conor Dooley 
Link: https://lore.kernel.org/all/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/
Signed-off-by: Alexandre Ghiti 
Reviewed-by: Conor Dooley 
Tested-by: Conor Dooley 
Link: https://lore.kernel.org/r/20230329081932.79831-2-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt

riscv: add icache flush for nommu sigreturn trampoline

2023-04-11T19:52:27+00:00

In a NOMMU kernel, sigreturn trampolines are generated on the user
stack by setup_rt_frame. Currently, these trampolines are not instruction
fenced, thus their visibility to ifetch is not guaranteed.

This patch adds a flush_icache_range in setup_rt_frame to fix this
problem.

Signed-off-by: Mathis Salmen 
Fixes: 6bd33e1ece52 ("riscv: add nommu support")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230406101130.82304-1-mathis.salmen@matsal.de
Signed-off-by: Palmer Dabbelt

RISC-V: Don't check text_mutex during stop_machine

2023-03-09T22:58:51+00:00

We're currently using stop_machine() to update ftrace & kprobes, which
means that the thread that takes text_mutex during may not be the same
as the thread that eventually patches the code.  This isn't actually a
race because the lock is still held (preventing any other concurrent
accesses) and there is only one thread running during stop_machine(),
but it does trigger a lockdep failure.

This patch just elides the lockdep check during stop_machine.

Fixes: c15ac4fd60d5 ("riscv/ftrace: Add dynamic function tracer support")
Suggested-by: Steven Rostedt 
Reported-by: Changbin Du 
Signed-off-by: Palmer Dabbelt 
Signed-off-by: Conor Dooley 
Link: https://lore.kernel.org/r/20230303143754.4005217-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt