On Wed, Nov 19, 2014 at 04:53:40PM -0500, David Miller wrote: > Pulled, thanks Al. Umm... Not in net-next.git#master... Anyway, the next portion is in vfs.git#iov_iter-net right now; I'll post it on netdev once I get some sleep. It's getting close to really interesting parts. Right now the main obstacle is in iscsit_do_rx_data/iscsit_do_tx_data; what happens there is reuse of iovec if kernel_sendmsg() gives a short write - it tries to send again, with the same iovec and decremented length. Ditto on RX side (with kernel_recvmsg(), obviously). As far as I can see, these retries on the send side are simply broken - normally we are talking to TCP sockets there and tcp_sendmsg() does *not* modify iovec in normal case. IOW, if you get 8K sent out of 80K, the next time it'll try to send 72K - already sent piece + 64K following it, etc. Could target-devel folks tell how realistic those resends are, in the first place? Both with TX and RX sides... Is there any sane limit on iovec size there, etc. Note that while conversion to iov_iter will provide a very simple solution (iovec remains unchanged, iterator advances and we just need to avoid reinitializing it for subsequent iterations in those loops), it won't solve the problem in older kernels; that code had been there since 2011 and iov_iter conversion is far too invasive for -stable. -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
