On Thu, Oct 04, 2018 at 09:58:37AM +0300, Dror Levin wrote: > CC'ing Greg. > > On Mon, Sep 3, 2018 at 11:34 AM Dror Levin <drorl@xxxxxxxxxxxxx> wrote: > > > > On Sun, Sep 2, 2018 at 8:55 PM Linus Torvalds > > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > > > On Sun, Sep 2, 2018 at 4:44 AM Richard Weinberger > > > <richard.weinberger@xxxxxxxxx> wrote: > > > > > > > > CC'ing relevant people. Otherwise your mail might get lost. > > > > > > Indeed. > > > > Sorry for that. > > > > > > On Sun, Sep 2, 2018 at 1:37 PM Dror Levin <drorl@xxxxxxxxxxxxx> wrote: > > > > > > > > > > We have an internal tool that uses the bsg read/write interface to > > > > > issue SCSI commands as part of a test suite for a storage device. > > > > > > > > > > After recently reading on LWN that this interface is to be removed we > > > > > tried porting our code to use sg instead. However, that raises new > > > > > issues - mainly getting ENOMEM over iSCSI for unknown reasons. > > > > > > Is there any chance that you can make more data available? > > > > Sure, I can try. > > > > We use writev() to send up to SG_MAX_QUEUE tasks at a time. Occasionally not > > all tasks are written at which point we wait for tasks to return before > > sending more, but then writev() fails with ENOMEM and we see this in the syslog: > > > > Sep 1 20:58:14 gdc-qa-io-017 kernel: sd 441:0:0:5: [sg73] > > sg_common_write: start_req err=-12 > > > > Failing tasks are reads of 128KiB. > > > > > I'd rather fix the sg interface (which while also broken garbage, we > > > can't get rid of) than re-surrect the bsg interface. > > Discussion seems to have died down but release of 4.19 is drawing near. > > Is there still any chance removal of bsg can be reconsidered? Maybe > postponed to the > next version to allow more time to adjust? > > I'm especially concerned about the possibility of this being > backported to stable kernels > which might leave us very little time to fix our code. What is being backported to what stable kernels and why? Is there sg patches? totally confused, greg k-h
