Re: update.c:undefined reference to `irq_work_queue'

[Randy Dunlap]

On 12/21/20 9:03 PM, Paul E. McKenney wrote:
> On Tue, Dec 22, 2020 at 11:24:22AM +0800, kernel test robot wrote:
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head:   8653b778e454a7708847aeafe689bce07aeeb94e
> > commit: b38f57c1fe64276773b124dffb0a139cc32ab3cb rcu-tasks: Allow rcu_read_unlock_trace() under scheduler locks
> > date:   8 months ago
> > config: h8300-randconfig-s032-20201220 (attached as .config)
> > compiler: h8300-linux-gcc (GCC) 9.3.0
> > reproduce:
> >          wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> >          chmod +x ~/bin/make.cross
> >          # apt-get install sparse
> >          # sparse version: v0.6.3-184-g1b896707-dirty
> >          # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b38f57c1fe64276773b124dffb0a139cc32ab3cb
> >          git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >          git fetch --no-tags linus master
> >          git checkout b38f57c1fe64276773b124dffb0a139cc32ab3cb
> >          # save the attached .config to linux build tree
> >          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=h8300
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >
> > All errors (new ones prefixed by >>):
> >
> >     h8300-linux-ld: section .init.text LMA [000000000043a160,0000000000452569] overlaps section .rodata LMA [00000000003ff420,000000000047df2f]
> >     h8300-linux-ld: section .data VMA [0000000000400000,000000000043a15f] overlaps section .rodata VMA [00000000003ff420,000000000047df2f]
> >     h8300-linux-ld: section __ksymtab VMA [000000000047df30,000000000048611f] overlaps section .bss VMA [000000000045ebd0,000000000056a053]
> >     h8300-linux-ld: kernel/rcu/update.o: in function `rcu_read_unlock_trace_special':
> > > > update.c:(.text+0x8f9): undefined reference to `irq_work_queue'
>
> Does the patch below help?
>
> 							Thanx, Paul
>
> ------------------------------------------------------------------------
>
> commit cb7220ed05190c9a92df95b52a21525a7e08a449
> Author: Paul E. McKenney <paulmck@xxxxxxxxxx>
> Date:   Mon Dec 21 21:00:18 2020 -0800
>
>      rcu: Make TASKS_TRACE_RCU select IRQ_WORK
>      
>      Tasks Trace RCU uses irq_work_queue() to safely awaken its grace-period
>      kthread, so this commit therefore causes the TASKS_TRACE_RCU Kconfig
>      option select the IRQ_WORK Kconfig option.
>      
>      Reported-by: kernel test robot <lkp@xxxxxxxxx>
>      Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
>
> diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig
> index aa8cc8c9..3128b7c 100644
> --- a/kernel/rcu/Kconfig
> +++ b/kernel/rcu/Kconfig
> @@ -95,6 +95,7 @@ config TASKS_RUDE_RCU
>   
>   config TASKS_TRACE_RCU
>   	def_bool 0
> +	select IRQ_WORK
>   	help
>   	  This option enables a task-based RCU implementation that uses
>   	  explicit rcu_read_lock_trace() read-side markers, and allows

WorksForMe. Thanks.

Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> # build-tested