On Fri, Oct 26, 2012 at 8:26 PM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > Please don't top-post. > > On Fri, 26 Oct 2012, megha dey wrote: > >> Hi, >> After applying this patch,we see that vfs_write is taking around 20 >> seconds.After this,from the bus traces we see that there are 2 >> consecutive CBW's and the corresponding CSW's are also out of >> order.How does f_mass_storage.c handle such a situation? > > Can you be more specific? Exactly what patch did you apply? And can > you provide either a debugging log or a usbmon trace showing the > packets that are out of order? > > Alan Stern > Hi, This is the patch I have applied. http://marc.info/?l=linux-usb&m=132024464410783&w=2 >From the trace attached,we see that write_10(highlighted command) is taking about 10 seconds,by which time the host is timing out.The host then sends the next test_unit_ready command without getting the status for the previous write.Thus,here we get 2 CBW's without an intervening CSW.
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