linux/arch/riscv/mm
Guo Ren c22b0bcb1d
riscv: Add kprobes supported
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>
2021-01-14 15:09:06 -08:00
..
cacheflush.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
context.c riscv: add nommu support 2019-11-17 15:17:39 -08:00
extable.c riscv: abstract out CSR names for supervisor vs machine mode 2019-11-05 09:20:42 -08:00
fault.c riscv: Add kprobes supported 2021-01-14 15:09:06 -08:00
hugetlbpage.c hugetlbfs: remove hugetlb_add_hstate() warning for existing hstate 2020-06-03 20:09:46 -07:00
init.c riscv: Add numa support for riscv64 platform 2021-01-14 15:08:58 -08:00
kasan_init.c arch, drivers: replace for_each_membock() with for_each_mem_range() 2020-10-13 18:38:35 -07:00
Makefile riscv: Fixup patch_text panic in ftrace 2021-01-14 15:09:04 -08:00
pageattr.c RISC-V Patches for the 5.11 Merge Window, Part 1 2020-12-18 10:43:07 -08:00
physaddr.c riscv: mm: add support for CONFIG_DEBUG_VIRTUAL 2020-01-23 10:40:06 -08:00
ptdump.c RISC-V: Add page table dump support for uefi 2020-10-02 14:31:33 -07:00
tlbflush.c RISC-V: Issue a tlb page flush if possible 2019-10-29 11:32:18 -07:00