Hi Song,
Thanks for the reviews.


Song Liu wrote:

On Fri, Oct 1, 2021 at 2:16 PM Naveen N. Rao
[off-list ref] wrote:

quoted

Add a helper to check if a given offset is within the branch range for a
powerpc conditional branch instruction, and update some sites to use the
new helper.

Signed-off-by: Naveen N. Rao <redacted>

Acked-by: Song Liu <redacted>

With one nitpick:

quoted

---
 arch/powerpc/include/asm/code-patching.h | 1 +
 arch/powerpc/lib/code-patching.c         | 7 ++++++-
 arch/powerpc/net/bpf_jit.h               | 7 +------
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h
index a95f63788c6b14..4ba834599c4d4c 100644
--- a/arch/powerpc/include/asm/code-patching.h
+++ b/arch/powerpc/include/asm/code-patching.h

@@ -23,6 +23,7 @@
 #define BRANCH_ABSOLUTE        0x2

 bool is_offset_in_branch_range(long offset);
+bool is_offset_in_cond_branch_range(long offset);
 int create_branch(struct ppc_inst *instr, const u32 *addr,
                  unsigned long target, int flags);
 int create_cond_branch(struct ppc_inst *instr, const u32 *addr,

diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index f9a3019e37b43c..e2342b9a1ab9c9 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c

@@ -228,6 +228,11 @@ bool is_offset_in_branch_range(long offset)
        return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3));
 }

+bool is_offset_in_cond_branch_range(long offset)
+{
+       return offset >= -0x8000 && offset <= 0x7FFF && !(offset & 0x3);
+}

Why not inline this one?

Good point. This was modeled after the existing 
is_offset_in_branch_range(), and I guess both of those helpers can be 
inlined. I'll do a separate patch for that.


- Naveen