| Message ID | 1402985736-32180-3-git-send-email-mpe@ellerman.id.au (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | b7b348c682fac04cade7b860c49d4a17f158dad4 |
| Headers | show |
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c index f5d1a34..8fc0c17 100644 --- a/arch/powerpc/kernel/ftrace.c +++ b/arch/powerpc/kernel/ftrace.c @@ -320,7 +320,7 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) } /* Ensure branch is within 24 bits */ - if (create_branch(ip, rec->arch.mod->arch.tramp, BRANCH_SET_LINK)) { + if (!create_branch(ip, rec->arch.mod->arch.tramp, BRANCH_SET_LINK)) { printk(KERN_ERR "Branch out of range"); return -EINVAL; }
In commit 24a1bdc35, "Fix ABIv2 issues with __ftrace_make_call", Anton changed the logic that creates and patches the branch, and added a thinko in the check of create_branch(). create_branch() returns the instruction that was generated, so if we get zero then it succeeded. The result is we can't ftrace modules: Branch out of range WARNING: at ../kernel/trace/ftrace.c:1638 ftrace failed to modify [<d000000004ba001c>] fuse_req_init_context+0x1c/0x90 [fuse] We should probably fix patch_instruction() to do that check and make the API saner, but that's a separate patch. For now just invert the test. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> --- arch/powerpc/kernel/ftrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)