[PATCH v4 09/15] riscv: extend execmem_params for generated code allocations

Mike Rapoport
2024-04-11T16:05:07Z

From: "Mike Rapoport (IBM)" <rppt@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().

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>
---
arch/riscv/kernel/module.c | 21 ++++++++++++++++++++-
arch/riscv/kernel/probes/kprobes.c | 10 ----------
arch/riscv/net/bpf_jit_core.c | 13 -------------
3 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index ad32e2a8621a..aad158bb2022 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -906,20 +906,39 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
return 0;
}

-#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
+#ifdef CONFIG_MMU
static struct execmem_info execmem_info __ro_after_init = {
.ranges = {
[EXECMEM_DEFAULT] = {
.pgprot = PAGE_KERNEL,
.alignment = 1,
},
+ [EXECMEM_KPROBES] = {
+ .pgprot = PAGE_KERNEL_READ_EXEC,
+ .alignment = 1,
+ },
+ [EXECMEM_BPF] = {
+ .pgprot = PAGE_KERNEL,
+ .alignment = PAGE_SIZE,
+ },
},
};

struct execmem_info __init *execmem_arch_setup(void)
{
+#ifdef CONFIG_64BIT
execmem_info.ranges[EXECMEM_DEFAULT].start = MODULES_VADDR;
execmem_info.ranges[EXECMEM_DEFAULT].end = MODULES_END;
+#else
+ execmem_info.ranges[EXECMEM_DEFAULT].start = VMALLOC_START;
+ execmem_info.ranges[EXECMEM_DEFAULT].end = VMALLOC_END;
+#endif
+
+ execmem_info.ranges[EXECMEM_KPROBES].start = VMALLOC_START;
+ execmem_info.ranges[EXECMEM_KPROBES].end = VMALLOC_END;
+
+ execmem_info.ranges[EXECMEM_BPF].start = BPF_JIT_REGION_START;
+ execmem_info.ranges[EXECMEM_BPF].end = BPF_JIT_REGION_END;

return &execmem_info;
}
diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
index 2f08c14a933d..e64f2f3064eb 100644
--- a/arch/riscv/kernel/probes/kprobes.c
+++ b/arch/riscv/kernel/probes/kprobes.c
@@ -104,16 +104,6 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
return 0;
}

-#ifdef CONFIG_MMU
-void *alloc_insn_page(void)
-{
- return __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
- GFP_KERNEL, PAGE_KERNEL_READ_EXEC,
- VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
- __builtin_return_address(0));
-}
-#endif
-
/* install breakpoint in text */
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c
index 6b3acac30c06..e238fdbd5dbc 100644
--- a/arch/riscv/net/bpf_jit_core.c
+++ b/arch/riscv/net/bpf_jit_core.c
@@ -219,19 +219,6 @@ u64 bpf_jit_alloc_exec_limit(void)
return BPF_JIT_REGION_SIZE;
}

-void *bpf_jit_alloc_exec(unsigned long size)
-{
- return __vmalloc_node_range(size, PAGE_SIZE, BPF_JIT_REGION_START,
- BPF_JIT_REGION_END, GFP_KERNEL,
- PAGE_KERNEL, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
-}
-
-void bpf_jit_free_exec(void *addr)
-{
- return vfree(addr);
-}
-
void *bpf_arch_text_copy(void *dst, void *src, size_t len)
{
int ret;
--
2.43.0