> -----Original Message----- > From: Thomas Monjalon [mailto:[email protected]] > Sent: Wednesday, November 8, 2017 7:57 AM > To: Yigit, Ferruh <[email protected]> > Cc: [email protected]; [email protected]; Tan, Jianfeng <[email protected]>; > Wu, Jingjing <[email protected]>; Shijith Thotton > <[email protected]>; Gregory Etelson <[email protected]>; > Harish Patil <[email protected]>; George Prekas > <[email protected]>; Gonzalez Monroy, Sergio > <[email protected]>; Rasesh Mody > <[email protected]>; Lee Roberts <[email protected]>; Stephen > Hemminger <[email protected]>; Chas Williams <[email protected]> > Subject: Re: [dpdk-dev] [PATCH v2] igb_uio: remove device reset in release > > 07/11/2017 23:29, Ferruh Yigit: > > More error reported for device reset in release() [1], when device > > pass-through to the guest, host kernel crash on guest exit. > > > > Removing the reset completely. > > > > This is close to reverting commit b58eedfc7dd5 [2], taking into > > account previous fix to remove reset in open as well [3], but not exactly > > same. > > > > With latest code, interrupts are enabled in uio open() callback and > > disabled in uio release() callback, so when a DPDK application exit > > device interrupts are disabled. Previously interrupts were only > > enabled once in igb_uio module insert and disabled in module removal. > > > > Also with latest code device set as bus master in open() and master > > cleared in release(), clearing bus master should prevent further DMA > > which was one of the target of the initial patch. > > > > The initial intention was also to reset the device to be sure it has > > been left in proper state, but currently that part is missing because > > of reported problem(s). > > > > Still igb_uio should be safer comparing to the pre b58eedfc7dd5 state. > > > > [1] > > http://dpdk.org/ml/archives/dev/2017-November/081459.html > > > > [2] > > b58eedfc7dd5 ("igb_uio: issue FLR during open and release of device > > file") > > > > [3] > > f73b38e9245d ("igb_uio: remove device reset in open") > > > > Fixes: e3a64deae2d5 ("igb_uio: prevent reset for bnx2x devices") > > Fixes: b58eedfc7dd5 ("igb_uio: issue FLR during open and release of > > device file") > > Cc: [email protected] > > > > Signed-off-by: Ferruh Yigit <[email protected]> > > We can say you tried hard to make igb_uio cleaner and safer :) > That's true! Thanks a lot, Ferruh!!
> Applied, thanks for the detailed explanations.
