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Documentation: riscv: cmodx: fix typos

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Fix typos in the dynamic ftrace section: atmoic -> atomic (twice),
pacthable -> patchable, derect -> directed.

Signed-off-by: Avi Radinsky <avi.radinsky@tennr.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/391d16fb-5f11-45fa-8f3b-1debe095695e@tennr.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
This commit is contained in:
Avi Radinsky 2026-04-29 18:35:23 -04:00 committed by Paul Walmsley
parent d272b8d2dd
commit a2e5b58811
1 changed files with 4 additions and 4 deletions
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8
Documentation/arch/riscv/cmodx.rst
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@ -21,13 +21,13 @@ call at each patchable function entry, and patches it dynamically at runtime to
enable or disable the redirection. In the case of RISC-V, 2 instructions,
AUIPC + JALR, are required to compose a function call. However, it is impossible
to patch 2 instructions and expect that a concurrent read-side executes them
without a race condition. This series makes atmoic code patching possible in
without a race condition. This series makes atomic code patching possible in
RISC-V ftrace. Kernel preemption makes things even worse as it allows the old
state to persist across the patching process with stop_machine().
In order to get rid of stop_machine() and run dynamic ftrace with full kernel
preemption, we partially initialize each patchable function entry at boot-time,
setting the first instruction to AUIPC, and the second to NOP. Now, atmoic
setting the first instruction to AUIPC, and the second to NOP. Now, atomic
patching is possible because the kernel only has to update one instruction.
According to Ziccif, as long as an instruction is naturally aligned, the ISA
guarantee an atomic update.
@ -36,8 +36,8 @@ By fixing down the first instruction, AUIPC, the range of the ftrace trampoline
is limited to +-2K from the predetermined target, ftrace_caller, due to the lack
of immediate encoding space in RISC-V. To address the issue, we introduce
CALL_OPS, where an 8B naturally align metadata is added in front of each
pacthable function. The metadata is resolved at the first trampoline, then the
execution can be derect to another custom trampoline.
patchable function. The metadata is resolved at the first trampoline, then the
execution can be directed to another custom trampoline.
CMODX in the User Space
-----------------------