Subject: [PATCH v6 10/16] arm64: extend execmem_info for generated code allocations

From: Mike Rapoport <[email-masked]>
Date: Fri, 26 Apr 2024 11:28:48 +0300

From: "Mike Rapoport (IBM)" <[email-masked]>

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-masked]>
Acked-by: Will Deacon <[email-masked]>
---
 arch/arm64/kernel/module.c         | 12 ++++++++++++
 arch/arm64/kernel/probes/kprobes.c |  7 -------
 arch/arm64/net/bpf_jit_comp.c      | 11 -----------
 3 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index b7a7a23f9f8f..a52240ea084b 100644
--- a/arch/arm64/kernel/module.c
+++ b/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,
+			},
 		},
 	};
 
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index 327855a11df2..4268678d0e86 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/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)
 {
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index 122021f9bdfc..456f5af239fc 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/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)
 {
-- 
2.43.0