On 5/31/2017 4:30 PM, Stephen Hemminger wrote: > On Wed, 31 May 2017 13:20:08 +0100 > Ferruh Yigit <ferruh.yi...@intel.com> wrote: > >> On 5/31/2017 12:09 PM, Shijith Thotton wrote: >>> Set UIO info device file operations open and release. Call pci reset >>> function inside open and release to clear device state at start and >>> end. Copied this behaviour from vfio_pci kernel module code. With this >>> change, it is not mandatory to issue FLR by PMD's during init and close. >> >> Cc: Jianfeng Tan <jianfeng....@intel.com> >> >> Jianfeng also implemented following patch: >> http://dpdk.org/dev/patchwork/patch/17495/ >> >> Which also implements release and open ops, for slightly different >> reason (prevent DMA access after app exit), but mainly both are to >> gracefully handle application exit status. >> >> btw, for Jianfeng's case, can adding pci_clear_master() in release and >> moving pci_set_master() to open help preventing unwanted DMA? >> >> >> Gregory, >> >> Can you please check if this patch fixes your issue? >> >> Thanks, >> ferruh > > pci_reset should stop all DMA. It also clears master status.
If so, should open() call pci_set_master(), currently it has been only called by igbuio_pci_probe() once?
