diff mbox series

[v5,3/5] powerpc/bpf: implement bpf_arch_text_invalidate for bpf_prog_pack

Message ID 20230928194818.261163-4-hbathini@linux.ibm.com (mailing list archive)
State Superseded
Headers show
Series powerpc/bpf: use BPF prog pack allocator | expand

Commit Message

Hari Bathini Sept. 28, 2023, 7:48 p.m. UTC 
Implement bpf_arch_text_invalidate and use it to fill unused part of
the bpf_prog_pack with trap instructions when a BPF program is freed.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
 arch/powerpc/net/bpf_jit_comp.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Comments

Song Liu Sept. 28, 2023, 9:09 p.m. UTC | #1 
On Thu, Sep 28, 2023 at 12:49 PM Hari Bathini <hbathini@linux.ibm.com> wrote:
>
> Implement bpf_arch_text_invalidate and use it to fill unused part of
> the bpf_prog_pack with trap instructions when a BPF program is freed.
>
> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>

Acked-by: Song Liu <song@kernel.org>
diff mbox series

Patch

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index c740eac8d584..ecd7cffbbe28 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -292,3 +292,18 @@  void *bpf_arch_text_copy(void *dst, void *src, size_t len)
 
 	return err ? ERR_PTR(err) : dst;
 }
+
+int bpf_arch_text_invalidate(void *dst, size_t len)
+{
+	u32 insn = BREAKPOINT_INSTRUCTION;
+	int ret;
+
+	if (WARN_ON_ONCE(core_kernel_text((unsigned long)dst)))
+		return -EINVAL;
+
+	mutex_lock(&text_mutex);
+	ret = patch_instructions(dst, &insn, len, true);
+	mutex_unlock(&text_mutex);
+
+	return ret;
+}