Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Nick Desaulniers <ndesaulniers@google.com>,
        Ondrej Mosnacek <omosnacek@gmail.com>,
        "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>,
        Michael Ellerman <mpe@ellerman.id.au>
Subject: [PATCH 5.19 1137/1157] powerpc64/ftrace: Fix ftrace for clang builds
Date:   Mon, 15 Aug 2022 20:08:13 +0200
Message-Id: <20220815180525.929733456@linuxfoundation.org>
In-Reply-To: <20220815180439.416659447@linuxfoundation.org>
References: <20220815180439.416659447@linuxfoundation.org>
User-Agent: quilt/0.67
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>

commit cb928ac192128c842f4c1cfc8b6780b95719d65f upstream.

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

Fixes: 23b44fc248f4 ("powerpc/ftrace: Make __ftrace_make_{nop/call}() common to PPC32 and PPC64")
Cc: stable@vger.kernel.org # v5.19+
Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Ondrej Mosnacek <omosnacek@gmail.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/llvm/llvm-project/issues/57031
Link: https://github.com/ClangBuiltLinux/linux/issues/1682
Link: https://lore.kernel.org/r/20220809095907.418764-1-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/trace/ftrace.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -392,11 +392,11 @@ 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
@@ -411,7 +411,7 @@ __ftrace_make_call(struct dyn_ftrace *re
 	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;