mm: jit/text allocator #6912
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mm: jit/text allocator #6912
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Since commit f6f37d9 ("arm64: select KASAN_VMALLOC for SW/HW_TAGS modes") KASAN_VMALLOC is always enabled when KASAN is on. This means that allocations in module_alloc() will be tracked by KASAN protection for vmalloc() and that kasan_alloc_module_shadow() will be always an empty inline and there is no point in calling it. Drop meaningless call to kasan_alloc_module_shadow() from module_alloc(). Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
and MODULE_END to MODULES_END to match other architectures that define custom address space for modules. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
nios2 uses kmalloc() to implement module_alloc() because CALL26/PCREL26 cannot reach all of vmalloc address space. Define module space as 32MiB below the kernel base and switch nios2 to use vmalloc for module allocations. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Dinh Nguyen <dinguyen@kernel.org> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Define MODULES_VADDR and MODULES_END as VMALLOC_START and VMALLOC_END for 32-bit and reduce module_alloc() to __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, ...) as with the new defines the allocations becomes identical for both 32 and 64 bits. While on it, drop unused include of <linux/jump_label.h> Suggested-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Move the logic related to the memory allocation and freeing into module_memory_alloc() and module_memory_free(). Signed-off-by: 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_alloc() and execmem_free() APIs. Initially, execmem_alloc() is a wrapper for module_alloc() and execmem_free() is a replacement of module_memfree() to allow updating all call sites to use the new APIs. Since architectures define different restrictions on placement, permissions, alignment and other parameters for memory that can be used by different subsystems that allocate executable memory, execmem_alloc() takes a type argument, that will be used to identify the calling subsystem and to allow architectures define parameters for ranges suitable for that subsystem. No functional changes. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Song Liu <song@kernel.org>
Several architectures override module_alloc() only to define address range for code allocations different than VMALLOC address space. Provide a generic implementation in execmem that uses the parameters for address space ranges, required alignment and page protections provided by architectures. The architectures must fill execmem_info structure and implement execmem_arch_setup() that returns a pointer to that structure. This way the execmem initialization won't be called from every architecture, but rather from a central place, namely a core_initcall() in execmem. The execmem provides execmem_alloc() API that wraps __vmalloc_node_range() with the parameters defined by the architectures. If an architecture does not implement execmem_arch_setup(), execmem_alloc() will fall back to module_alloc(). Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Song Liu <song@kernel.org>
Extend execmem parameters to accommodate more complex overrides of module_alloc() by architectures. This includes specification of a fallback range required by arm, arm64 and powerpc, EXECMEM_MODULE_DATA type required by powerpc, support for allocation of KASAN shadow required by s390 and x86 and support for late initialization of execmem required by arm64. The core implementation of execmem_alloc() takes care of suppressing warnings when the initial allocation fails but there is a fallback range defined. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Song Liu <song@kernel.org>
The memory allocations for kprobes and BPF on RISC-V are not placed in the modules area and these custom allocations are implemented with overrides of alloc_insn_page() and bpf_jit_alloc_exec(). Define MODULES_VADDR and MODULES_END as VMALLOC_START and VMALLOC_END for 32 bit and slightly reorder execmem_params initialization to support both 32 and 64 bit variants, define EXECMEM_KPROBES and EXECMEM_BPF ranges in riscv::execmem_params and drop overrides of alloc_insn_page() and bpf_jit_alloc_exec(). Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
The memory allocations for kprobes and BPF on arm64 can be placed anywhere in vmalloc address space and currently this is implemented with overrides of alloc_insn_page() and bpf_jit_alloc_exec() in arm64. Define EXECMEM_KPROBES and EXECMEM_BPF ranges in arm64::execmem_info and drop overrides of alloc_insn_page() and bpf_jit_alloc_exec(). Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Will Deacon <will@kernel.org>
powerpc overrides kprobes::alloc_insn_page() to remove writable permissions when STRICT_MODULE_RWX is on. Add definition of EXECMEM_KRPOBES to execmem_params to allow using the generic kprobes::alloc_insn_page() with the desired permissions. As powerpc uses breakpoint instructions to inject kprobes, it does not need to constrain kprobe allocations to the modules area and can use the entire vmalloc address space. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
execmem does not depend on modules, on the contrary modules use execmem. To make execmem available when CONFIG_MODULES=n, for instance for kprobes, split execmem_params initialization out from arch/*/kernel/module.c and compile it when CONFIG_EXECMEM=y Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Dynamic ftrace must allocate memory for code and this was impossible without CONFIG_MODULES. With execmem separated from the modules code, execmem_text_alloc() is available regardless of CONFIG_MODULES. Remove dependency of dynamic ftrace on CONFIG_MODULES and make CONFIG_DYNAMIC_FTRACE select CONFIG_EXECMEM in Kconfig. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
There are places where CONFIG_MODULES guards the code that depends on memory allocation being done with module_alloc(). Replace CONFIG_MODULES with CONFIG_EXECMEM in such places. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
kprobes depended on CONFIG_MODULES because it has to allocate memory for code. Since code allocations are now implemented with execmem, kprobes can be enabled in non-modular kernels. Add #ifdef CONFIG_MODULE guards for the code dealing with kprobes inside modules, make CONFIG_KPROBES select CONFIG_EXECMEM and drop the dependency of CONFIG_KPROBES on CONFIG_MODULES. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
BPF just-in-time compiler depended on CONFIG_MODULES because it used module_alloc() to allocate memory for the generated code. Since code allocations are now implemented with execmem, drop dependency of CONFIG_BPF_JIT on CONFIG_MODULES and make it select CONFIG_EXECMEM. Suggested-by: Björn Töpel <bjorn@kernel.org> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
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Upstream branch: b867247 |
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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=848857 irrelevant now. Closing PR. |
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Pull request for series with
subject: mm: jit/text allocator
version: 7
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=848857