On Tue, Apr 27 2021 at 11:00, kernel test robot wrote: Cc+ sparse folks > tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git x86/l1dflush > head: 6955fbfdad4241331d1e33362306aec3a410803a > commit: 193cb89595f7f3f4549b03ab9392fb9838d123e3 [7/9] x86/mm: Prepare for opt-in based L1D flush in switch_mm() > config: i386-randconfig-s032-20210426 (attached as .config) > compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 > reproduce: > # apt-get install sparse > # sparse version: v0.6.3-341-g8af24329-dirty > # https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git/commit/?id=193cb89595f7f3f4549b03ab9392fb9838d123e3 > git remote add tglx-devel https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git > git fetch --no-tags tglx-devel x86/l1dflush > git checkout 193cb89595f7f3f4549b03ab9392fb9838d123e3 > # save the attached .config to linux build tree > make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' W=1 ARCH=i386 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <lkp@xxxxxxxxx> > > > sparse warnings: (new ones prefixed by >>) >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * >>> arch/x86/mm/tlb.c:354:13: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] __percpu *__vpp_verify @@ got bool * @@ > arch/x86/mm/tlb.c:354:13: sparse: expected void const [noderef] __percpu *__vpp_verify > arch/x86/mm/tlb.c:354:13: sparse: got bool * > > vim +354 arch/x86/mm/tlb.c > > 336 > 337 static void l1d_flush_evaluate(unsigned long prev_mm, unsigned long next_mm, > 338 struct task_struct *next) > 339 { > 340 /* Flush L1D if the outgoing task requests it */ > 341 if (prev_mm & LAST_USER_MM_L1D_FLUSH) > 342 wrmsrl(MSR_IA32_FLUSH_CMD, L1D_FLUSH); > 343 > 344 /* Check whether the incoming task opted in for L1D flush */ > 345 if (likely(!(next_mm & LAST_USER_MM_L1D_FLUSH))) > 346 return; > 347 > 348 /* > 349 * Validate that it is not running on an SMT sibling as this would > 350 * make the excercise pointless because the siblings share L1D. If > 351 * it runs on a SMT sibling, notify it with SIGBUS on return to > 352 * user/guest > 353 */ > > 354 if (this_cpu_read(cpu_info.smt_active)) { That's a valid construct and the kernel of full of percpuvar.member reads/writes. > 355 clear_ti_thread_flag(&next->thread_info, TIF_SPEC_L1D_FLUSH); > 356 next->l1d_flush_kill.func = l1d_flush_force_sigbus; > 357 task_work_add(next, &next->l1d_flush_kill, TWA_RESUME); > 358 } > 359 } > 360 Thanks, tglx
