Re: [PATCH v3 07/13] arm64, execmem: extend execmem_params for generated code allocations

2023-10-23 Thread Will Deacon 
On Mon, Sep 18, 2023 at 10:29:49AM +0300, Mike Rapoport wrote:
> From: "Mike Rapoport (IBM)" 
> 
> 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_params and
> drop overrides of alloc_insn_page() and bpf_jit_alloc_exec().
> 
> Signed-off-by: Mike Rapoport (IBM) 
> ---
>  arch/arm64/kernel/module.c | 13 +
>  arch/arm64/kernel/probes/kprobes.c |  7 ---
>  arch/arm64/net/bpf_jit_comp.c  | 11 ---
>  3 files changed, 13 insertions(+), 18 deletions(-)
> 
> diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
> index cd6320de1c54..d27db168d2a2 100644
> --- a/arch/arm64/kernel/module.c
> +++ b/arch/arm64/kernel/module.c
> @@ -116,6 +116,16 @@ static struct execmem_params execmem_params 
> __ro_after_init = {
>   .flags = EXECMEM_KASAN_SHADOW,
>   .alignment = MODULE_ALIGN,
>   },
> + [EXECMEM_KPROBES] = {
> + .start = VMALLOC_START,
> + .end = VMALLOC_END,
> + .alignment = 1,
> + },
> + [EXECMEM_BPF] = {
> + .start = VMALLOC_START,
> + .end = VMALLOC_END,
> + .alignment = 1,
> + },
>   },
>  };
>  
> @@ -140,6 +150,9 @@ struct execmem_params __init *execmem_arch_params(void)
>   r->end = module_plt_base + SZ_2G;
>   }
>  
> + execmem_params.ranges[EXECMEM_KPROBES].pgprot = PAGE_KERNEL_ROX;
> + execmem_params.ranges[EXECMEM_BPF].pgprot = PAGE_KERNEL;
> +
>   return _params;
>  }
>  
> diff --git a/arch/arm64/kernel/probes/kprobes.c 
> b/arch/arm64/kernel/probes/kprobes.c
> index 70b91a8c6bb3..6fccedd02b2a 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));
> -}

It's slightly curious that we didn't clear the tag here, so it's nice that
it all happens magically with your series:

Acked-by: Will Deacon 

Will

[PATCH v3 07/13] arm64, execmem: extend execmem_params for generated code allocations

2023-09-18 Thread Mike Rapoport 
From: "Mike Rapoport (IBM)" 

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_params and
drop overrides of alloc_insn_page() and bpf_jit_alloc_exec().

Signed-off-by: Mike Rapoport (IBM) 
---
 arch/arm64/kernel/module.c | 13 +
 arch/arm64/kernel/probes/kprobes.c |  7 ---
 arch/arm64/net/bpf_jit_comp.c  | 11 ---
 3 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index cd6320de1c54..d27db168d2a2 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -116,6 +116,16 @@ static struct execmem_params execmem_params 
__ro_after_init = {
.flags = EXECMEM_KASAN_SHADOW,
.alignment = MODULE_ALIGN,
},
+   [EXECMEM_KPROBES] = {
+   .start = VMALLOC_START,
+   .end = VMALLOC_END,
+   .alignment = 1,
+   },
+   [EXECMEM_BPF] = {
+   .start = VMALLOC_START,
+   .end = VMALLOC_END,
+   .alignment = 1,
+   },
},
 };
 
@@ -140,6 +150,9 @@ struct execmem_params __init *execmem_arch_params(void)
r->end = module_plt_base + SZ_2G;
}
 
+   execmem_params.ranges[EXECMEM_KPROBES].pgprot = PAGE_KERNEL_ROX;
+   execmem_params.ranges[EXECMEM_BPF].pgprot = PAGE_KERNEL;
+
return _params;
 }
 
diff --git a/arch/arm64/kernel/probes/kprobes.c 
b/arch/arm64/kernel/probes/kprobes.c
index 70b91a8c6bb3..6fccedd02b2a 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 150d1c6543f7..3a7590f828d1 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -1687,17 +1687,6 @@ 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)
 {
-- 
2.39.2