arm64: extend execmem_info for generated code allocations

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) <[email protected]>
Acked-by: Will Deacon <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

Author: rppt

arch/arm64/kernel/module.c

@@ -146,6 +146,18 @@ struct execmem_info __init *execmem_arch_setup(void)
 				.fallback_start	= fallback_start,
 				.fallback_end	= fallback_end,
 			},
+			[EXECMEM_KPROBES] = {
+				.start	= VMALLOC_START,
+				.end	= VMALLOC_END,
+				.pgprot	= PAGE_KERNEL_ROX,
+				.alignment = 1,
+			},
+			[EXECMEM_BPF] = {
+				.start	= VMALLOC_START,
+				.end	= VMALLOC_END,
+				.pgprot	= PAGE_KERNEL,
+				.alignment = 1,
+			},
 		},
 	};
 

arch/arm64/kernel/probes/kprobes.c

@@ -129,13 +129,6 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
 	return 0;
 }
 
-void *alloc_insn_page(void)
-{
-	return __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
-			GFP_KERNEL, PAGE_KERNEL_ROX, VM_FLUSH_RESET_PERMS,
-			NUMA_NO_NODE, __builtin_return_address(0));
-}
-
 /* arm kprobe: install breakpoint in text */
 void __kprobes arch_arm_kprobe(struct kprobe *p)
 {

arch/arm64/net/bpf_jit_comp.c

@@ -1793,17 +1793,6 @@ u64 bpf_jit_alloc_exec_limit(void)
 	return VMALLOC_END - VMALLOC_START;
 }
 
-void *bpf_jit_alloc_exec(unsigned long size)
-{
-	/* Memory is intended to be executable, reset the pointer tag. */
-	return kasan_reset_tag(vmalloc(size));
-}
-
-void bpf_jit_free_exec(void *addr)
-{
-	return vfree(addr);
-}
-
 /* Indicate the JIT backend supports mixing bpf2bpf and tailcalls. */
 bool bpf_jit_supports_subprog_tailcalls(void)
 {