[arm64:for-next/misc 13/14] ld.lld: error: undefined symbol: sve_get_vl

[Catalin Marinas]

On Thu, Apr 15, 2021 at 07:13:41AM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/misc
> head:   839157876f97fcc7ead0b62c9377bb50f75a3df9
> commit: ef9c5d09797db874a29a97407c3ea3990210432b [13/14] arm64/sve: Remove redundant system_supports_sve() tests
> config: arm64-randconfig-r036-20210414 (attached as .config)
> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 9829f5e6b1bca9b61efc629770d28bb9014dec45)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install arm64 cross compiling tool for clang build
>         # apt-get install binutils-aarch64-linux-gnu
>         # https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/commit/?id=ef9c5d09797db874a29a97407c3ea3990210432b
>         git remote add arm64 https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git
>         git fetch --no-tags arm64 for-next/misc
>         git checkout ef9c5d09797db874a29a97407c3ea3990210432b
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=arm64 
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp at intel.com>

Thanks for the report. That indeed triggers if CONFIG_ARM64_SVE is
disabled. Proposed fix:

diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index f6cd89131dc3..9d433854a662 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -285,7 +285,7 @@ static void task_fpsimd_load(void)
 	WARN_ON(!system_supports_fpsimd());
 	WARN_ON(!have_cpu_fpsimd_context());
 
-	if (test_thread_flag(TIF_SVE))
+	if (IS_ENABLED(CONFIG_ARM64_SVE) && test_thread_flag(TIF_SVE))
 		sve_load_state(sve_pffr(&current->thread),
 			       &current->thread.uw.fpsimd_state.fpsr,
 			       sve_vq_from_vl(current->thread.sve_vl) - 1);
@@ -307,7 +307,7 @@ static void fpsimd_save(void)
 	WARN_ON(!have_cpu_fpsimd_context());
 
 	if (!test_thread_flag(TIF_FOREIGN_FPSTATE)) {
-		if (test_thread_flag(TIF_SVE)) {
+		if (IS_ENABLED(CONFIG_ARM64_SVE) && test_thread_flag(TIF_SVE)) {
 			if (WARN_ON(sve_get_vl() != last->sve_vl)) {
 				/*
 				 * Can't save the user regs, so current would

-- 
Catalin