[ Quoting Samuel Holland: ]
This is a separate issue, but using ".option rvc" here is a bug.
It will unconditionally enable the C extension for the rest of
the file, even if the kernel is being built with CONFIG_RISCV_ISA_C=n.
[ Quoting Palmer Dabbelt: ]
We're just looking at the address of kgdb_compiled_break, so it's
fine if it ends up as a c.ebreak.
[ Quoting Alexandre Ghiti: ]
.option norvc is used to prevent the assembler from using compressed
instructions, but it's generally used when we need to ensure the
size of the instructions that are used, which is not the case here
as noted by Palmer since we only care about the address. So yes
it will work fine with C enabled :)
So let's just remove them all.
Link: https://lore.kernel.org/all/4b4187c1-77e5-44b7-885f-d6826723dd9a@sifive.com/
Link: https://lore.kernel.org/all/mhng-69513841-5068-441d-be8f-2aeebdc56a08@palmer-ri-x1c9a/
Link: https://lore.kernel.org/all/23693e7f-4fff-40f3-a437-e06d827278a5@ghiti.fr/
Fixes: fe89bd2be8 ("riscv: Add KGDB support")
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Link: https://lore.kernel.org/r/8B431C6A4626225C+20250411073222.56820-2-wangyuli@uniontech.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The current parse_asm header should become a more centralized place
for everything concerning parsing and constructing instructions.
We already have a header insn-def.h similar to aarch64, so rename
parse_asm.h to insn.h (again similar to aarch64) to show that it's
meant for more than simple instruction parsing.
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/20221223221332.4127602-8-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Right now the riscv kernel has (at least) two independent sets
of functions to check if an encoded instruction is of a specific
type. One in kgdb and one kprobes simulate-insn code.
More parts of the kernel will probably need this in the future,
so instead of allowing this duplication to go on further,
move macros that do the function declaration in a common header,
similar to at least aarch64.
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/20221223221332.4127602-7-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Some of the constants and macros already have suitable RV_, RVG_ or
RVC_ prefixes.
Extend this to the rest of the file as well, as we want to use these
things in a broader scope soon.
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/20221223221332.4127602-3-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Some functions are only used in the kgdb.c file. Add static properities
to these functions to avoid "no previous prototype" compile warnings
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Better describe what this helper does, and match the naming of
copy_from_kernel_nofault.
Also switch the argument order around, so that it acts and looks
like get_user().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In KGDB, the GDB in the host is responsible for the single-step operation
of the software. In other words, KGDB does not need to derive the next pc
address when performing a software single-step operation. KGDB just inserts
the break instruction at the indicated address according to the GDB
instructions. This approach does not work in KDB because the GDB does not
involve the KDB process. Therefore, this patch provides KDB a software
single-step mechanism to use.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The $status, $badaddr, and $cause registers belong to the thread context,
so KGDB can obtain their contents from pt_regs in each trap. However, the
sequential number of these registers in the gdb register list is far from
the general-purpose registers. If riscv port uses the existing method to
report these three registers, many trivial registers with sequence numbers
in the middle of them will also be packaged to the reply packets. To solve
this problem, the riscv port wants to introduce the GDB target description
mechanism to customize the reported register list. By the list, the KGDB
can ignore the intermediate registers and just reports the general-purpose
registers and these three system registers.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
