From: Breno Leitao Date: Tue, 6 Jan 2026 10:16:35 +0000 (-0800) Subject: arm64: Disable branch profiling for all arm64 code X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f22c81bebf8bda6e54dc132df0ed54f6bf8756f9;p=thirdparty%2Fkernel%2Flinux.git arm64: Disable branch profiling for all arm64 code The arm64 kernel doesn't boot with annotated branches (PROFILE_ANNOTATED_BRANCHES) enabled and CONFIG_DEBUG_VIRTUAL together. Bisecting it, I found that disabling branch profiling in arch/arm64/mm solved the problem. Narrowing down a bit further, I found that physaddr.c is the file that needs to have branch profiling disabled to get the machine to boot. I suspect that it might invoke some ftrace helper very early in the boot process and ftrace is still not enabled(!?). Rather than playing whack-a-mole with individual files, disable branch profiling for the entire arch/arm64 tree, similar to what x86 already does in arch/x86/Kbuild. Cc: stable@vger.kernel.org Signed-off-by: Breno Leitao Acked-by: Mark Rutland Signed-off-by: Will Deacon --- diff --git a/arch/arm64/Kbuild b/arch/arm64/Kbuild index 5bfbf7d79c99b..d876bc0e54211 100644 --- a/arch/arm64/Kbuild +++ b/arch/arm64/Kbuild @@ -1,4 +1,8 @@ # SPDX-License-Identifier: GPL-2.0-only + +# Branch profiling isn't noinstr-safe +subdir-ccflags-$(CONFIG_TRACE_BRANCH_PROFILING) += -DDISABLE_BRANCH_PROFILING + obj-y += kernel/ mm/ net/ obj-$(CONFIG_KVM) += kvm/ obj-$(CONFIG_XEN) += xen/