Instructions can write to x0, so we should simulate these instructions
normally.
Currently, the kernel hangs if an instruction who writes to x0 is
simulated.
Fixes: c22b0bcb1d ("riscv: Add kprobes supported")
Cc: stable@vger.kernel.org
Signed-off-by: Nam Cao <namcaov@gmail.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Acked-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20230829182500.61875-1-namcaov@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Conor Dooley <conor@kernel.org> says:
From: Conor Dooley <conor.dooley@microchip.com>
Ever since RISC-V starting using generic arch topology code, the code
paths for cpu-capacity have been there but there's no binding defined to
actually convey the information. Defining the same property as used on
arm seems to be the only logical thing to do, so do it.
[Palmer: This is on top of the fix required to make it work, which
itself wasn't merged until late in the 6.2 cycle and thus pulls in
various other fixes.]
* b4-shazam-merge:
dt-bindings: riscv: add a capacity-dmips-mhz cpu property
dt-bindings: arm: move cpu-capacity to a shared loation
riscv: Move call to init_cpu_topology() to later initialization stage
riscv/kprobe: Fix instruction simulation of JALR
riscv: fix -Wundef warning for CONFIG_RISCV_BOOT_SPINWAIT
MAINTAINERS: add an IRC entry for RISC-V
RISC-V: fix compile error from deduplicated __ALTERNATIVE_CFG_2
dt-bindings: riscv: fix single letter canonical order
dt-bindings: riscv: fix underscore requirement for multi-letter extensions
riscv: uaccess: fix type of 0 variable on error in get_user()
riscv, kprobes: Stricter c.jr/c.jalr decoding
Link: https://lore.kernel.org/r/20230104180513.1379453-1-conor@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Don't redefine values that are already available in the central header
asm/insn.h . Use the values from there instead.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Link: https://lore.kernel.org/r/20221223221332.4127602-9-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This has been tested by probing a module that contains each of the
flavors of branches we have.
Signed-off-by: Chen Lifu <chenlifu@huawei.com>
[Palmer: commit message, fix kconfig errors]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This has been tested by probing a module that contains an auipc
instruction.
Signed-off-by: Chen Lifu <chenlifu@huawei.com>
[Palmer: commit message]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch enables "kprobe & kretprobe" to work with ftrace
interface. It utilized software breakpoint as single-step
mechanism.
Some instructions which can't be single-step executed must be
simulated in kernel execution slot, such as: branch, jal, auipc,
la ...
Some instructions should be rejected for probing and we use a
blacklist to filter, such as: ecall, ebreak, ...
We use ebreak & c.ebreak to replace origin instruction and the
kprobe handler prepares an executable memory slot for out-of-line
execution with a copy of the original instruction being probed.
In execution slot we add ebreak behind original instruction to
simulate a single-setp mechanism.
The patch is based on packi's work [1] and csky's work [2].
- The kprobes_trampoline.S is all from packi's patch
- The single-step mechanism is new designed for riscv without hw
single-step trap
- The simulation codes are from csky
- Frankly, all codes refer to other archs' implementation
[1] https://lore.kernel.org/linux-riscv/20181113195804.22825-1-me@packi.ch/
[2] https://lore.kernel.org/linux-csky/20200403044150.20562-9-guoren@kernel.org/
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Co-developed-by: Patrick Stählin <me@packi.ch>
Signed-off-by: Patrick Stählin <me@packi.ch>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: Patrick Stählin <me@packi.ch>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
