Re: [PATCH] virtio-mmio: harden interrupt

[Jason Wang]

On Thu, Nov 25, 2021 at 8:08 PM kernel test robot <lkp@xxxxxxxxx> wrote:
>
> Hi Jason,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on linus/master]
> [also build test WARNING on v5.16-rc2 next-20211125]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch]

Will fix this in V2.

Thanks

>
> url:    https://github.com/0day-ci/linux/commits/Jason-Wang/virtio-mmio-harden-interrupt/20211125-143334
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 5f53fa508db098c9d372423a6dac31c8a5679cdf
> config: mips-buildonly-randconfig-r003-20211125 (https://download.01.org/0day-ci/archive/20211125/202111252001.Z5tli1Np-lkp@xxxxxxxxx/config)
> compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 67a1c45def8a75061203461ab0060c75c864df1c)
> 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 mips cross compiling tool for clang build
>         # apt-get install binutils-mips-linux-gnu
>         # https://github.com/0day-ci/linux/commit/e19a8a1a95bd891090863b2d6828b8dc55d3633f
>         git remote add linux-review https://github.com/0day-ci/linux
>         git fetch --no-tags linux-review Jason-Wang/virtio-mmio-harden-interrupt/20211125-143334
>         git checkout e19a8a1a95bd891090863b2d6828b8dc55d3633f
>         # save the config file to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=mips
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/virtio/virtio_mmio.c:105:6: warning: no previous prototype for function 'vm_disable_cbs' [-Wmissing-prototypes]
>    void vm_disable_cbs(struct virtio_device *vdev)
>         ^
>    drivers/virtio/virtio_mmio.c:105:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>    void vm_disable_cbs(struct virtio_device *vdev)
>    ^
>    static
> >> drivers/virtio/virtio_mmio.c:121:6: warning: no previous prototype for function 'vm_enable_cbs' [-Wmissing-prototypes]
>    void vm_enable_cbs(struct virtio_device *vdev)
>         ^
>    drivers/virtio/virtio_mmio.c:121:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>    void vm_enable_cbs(struct virtio_device *vdev)
>    ^
>    static
>    2 warnings generated.
>
>
> vim +/vm_disable_cbs +105 drivers/virtio/virtio_mmio.c
>
>    103
>    104  /* disable irq handlers */
>  > 105  void vm_disable_cbs(struct virtio_device *vdev)
>    106  {
>    107          struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
>    108          int irq = platform_get_irq(vm_dev->pdev, 0);
>    109
>    110          /*
>    111           * The below synchronize() guarantees that any
>    112           * interrupt for this line arriving after
>    113           * synchronize_irq() has completed is guaranteed to see
>    114           * intx_soft_enabled == false.
>    115           */
>    116          WRITE_ONCE(vm_dev->intr_soft_enabled, false);
>    117          synchronize_irq(irq);
>    118  }
>    119
>    120  /* enable irq handlers */
>  > 121  void vm_enable_cbs(struct virtio_device *vdev)
>    122  {
>    123          struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
>    124          int irq = platform_get_irq(vm_dev->pdev, 0);
>    125
>    126          disable_irq(irq);
>    127          /*
>    128           * The above disable_irq() provides TSO ordering and
>    129           * as such promotes the below store to store-release.
>    130           */
>    131          WRITE_ONCE(vm_dev->intr_soft_enabled, true);
>    132          enable_irq(irq);
>    133          return;
>    134  }
>    135
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
>