Re: [PATCH v3 4/8] s390/airq: use DMA memory for adapter interrupts

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, 29 May 2019 14:26:53 +0200
Michael Mueller <mimu@xxxxxxxxxxxxx> wrote:

> From: Halil Pasic <pasic@xxxxxxxxxxxxx>
> 
> Protected virtualization guests have to use shared pages for airq
> notifier bit vectors, because hypervisor needs to write these bits.
> 
> Let us make sure we allocate DMA memory for the notifier bit vectors by
> replacing the kmem_cache with a dma_cache and kalloc() with
> cio_dma_zalloc().
> 
> Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
> Reviewed-by: Sebastian Ott <sebott@xxxxxxxxxxxxx>
> Signed-off-by: Michael Mueller <mimu@xxxxxxxxxxxxx>
> ---
>  arch/s390/include/asm/airq.h |  2 ++
>  drivers/s390/cio/airq.c      | 32 ++++++++++++++++++++------------
>  drivers/s390/cio/cio.h       |  2 ++
>  drivers/s390/cio/css.c       |  1 +
>  4 files changed, 25 insertions(+), 12 deletions(-)

Apologies if that already has been answered (and I missed it in my mail
pile...), but two things had come to my mind previously:

- CHSC... does anything need to be done there? Last time I asked:
  "Anyway, css_bus_init() uses some chscs
   early (before cio_dma_pool_init), so we could not use the pools
   there, even if we wanted to. Do chsc commands either work, or else
   fail benignly on a protected virt guest?"
- PCI indicators... does this interact with any dma configuration on
  the pci device? (I know pci is not supported yet, and I don't really
  expect any problems.)



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux