Commit cb928ac1 authored Aug 09, 2022 by Naveen N Rao Committed by Michael Ellerman Aug 10, 2022

powerpc64/ftrace: Fix ftrace for clang builds



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

Fixes: 23b44fc2 ("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

parent 5cccf7a5

arch/powerpc/kernel/trace/ftrace.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -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;