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    SubjectRe: [PATCH v2 02/12] mm: introduce execmem_text_alloc() and jit_text_alloc()
    On Fri, Jun 16, 2023, at 1:50 AM, Mike Rapoport wrote:
    > From: "Mike Rapoport (IBM)" <rppt@kernel.org>
    >
    > module_alloc() is used everywhere as a mean to allocate memory for code.
    >
    > Beside being semantically wrong, this unnecessarily ties all subsystems
    > that need to allocate code, such as ftrace, kprobes and BPF to modules
    > and puts the burden of code allocation to the modules code.
    >
    > Several architectures override module_alloc() because of various
    > constraints where the executable memory can be located and this causes
    > additional obstacles for improvements of code allocation.
    >
    > Start splitting code allocation from modules by introducing
    > execmem_text_alloc(), execmem_free(), jit_text_alloc(), jit_free() APIs.
    >
    > Initially, execmem_text_alloc() and jit_text_alloc() are wrappers for
    > module_alloc() and execmem_free() and jit_free() are replacements of
    > module_memfree() to allow updating all call sites to use the new APIs.
    >
    > The intention semantics for new allocation APIs:
    >
    > * execmem_text_alloc() should be used to allocate memory that must reside
    > close to the kernel image, like loadable kernel modules and generated
    > code that is restricted by relative addressing.
    >
    > * jit_text_alloc() should be used to allocate memory for generated code
    > when there are no restrictions for the code placement. For
    > architectures that require that any code is within certain distance
    > from the kernel image, jit_text_alloc() will be essentially aliased to
    > execmem_text_alloc().
    >

    Is there anything in this series to help users do the appropriate synchronization when the actually populate the allocated memory with code? See here, for example:

    https://lore.kernel.org/linux-fsdevel/cb6533c6-cea0-4f04-95cf-b8240c6ab405@app.fastmail.com/T/#u

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