[PATCH] powerpc64/ftrace: Fix ftrace for clang builds

Naveen N. Rao naveen.n.rao at linux.vnet.ibm.com
Tue Aug 9 19:59:07 AEST 2022


Clang doesn't support -mprofile-kernel ABI, so guard the checks against
CONFIG_DYNAMIC_FTRACE_WITH_REGS, rather than the elf ABI version.

Fixes: 23b44fc248f420 ("powerpc/ftrace: Make __ftrace_make_{nop/call}() common to PPC32 and PPC64")
Reported-by: Nick Desaulniers <ndesaulniers at google.com>
Reported-by: Ondrej Mosnacek <omosnacek at gmail.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao at linux.vnet.ibm.com>
---
 arch/powerpc/kernel/trace/ftrace.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index cb158c32b50b99..7b85c3b460a3c0 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -393,11 +393,11 @@ int ftrace_make_nop(struct module *mod,
  */
 static bool expected_nop_sequence(void *ip, ppc_inst_t op0, ppc_inst_t op1)
 {
-	if (IS_ENABLED(CONFIG_PPC64_ELF_ABI_V1))
+	if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS))
+		return ppc_inst_equal(op0, ppc_inst(PPC_RAW_NOP()));
+	else
 		return ppc_inst_equal(op0, ppc_inst(PPC_RAW_BRANCH(8))) &&
 		       ppc_inst_equal(op1, ppc_inst(PPC_INST_LD_TOC));
-	else
-		return ppc_inst_equal(op0, ppc_inst(PPC_RAW_NOP()));
 }
 
 static int
@@ -412,7 +412,7 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 	if (copy_inst_from_kernel_nofault(op, ip))
 		return -EFAULT;
 
-	if (IS_ENABLED(CONFIG_PPC64_ELF_ABI_V1) &&
+	if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS) &&
 	    copy_inst_from_kernel_nofault(op + 1, ip + 4))
 		return -EFAULT;
 

base-commit: ff1ed171e05c971652a0ede3d716997de8ee41c9
-- 
2.37.1



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