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+KVM: 0.893
+device: 0.877
+network: 0.813
+graphic: 0.785
+instruction: 0.665
+semantic: 0.654
+other: 0.570
+mistranslation: 0.555
+boot: 0.388
+socket: 0.364
+vnc: 0.364
+assembly: 0.132
+
+Memory synchronization error between kvm and target, e1000(dpdk)
+
+Hi folks.
+
+I use linux with dpdk drivers on the target system, and e1000 emulation device with tap interface for host. I use kvm for accelerate.
+Version qemu 4.0.94 and master (Nov 12 10:14:33 2019)
+Version dpdk stable-17.11.4
+Version linux host 4.15.0-66-generic (ubuntu 18.04)
+
+I type command "ping <target ip> -f" and wait about 1-2 minutes. Network subsystem freezes.
+
+For receive the eth pack from host system (tap interface) to host system the e1000 using ring buffer. 
+
+The e1000 write body of eth pack, set E1000_RXD_STAT_DD flag and move RDH (Ring Device Head).
+(file hw/net/e1000.c function e1000_receive_iov() )
+
+The dpdk driver is reading from E1000_RXD_STAT_DD flags (ignoring RDH), if flag is set: read buffer, unset flag E1000_RXD_STAT_DD and move RDT (Ring Device Tail).
+(source drivers/net/e1000/em_rxtx.c function eth_em_recv_scattered_pkts() )
+
+I see what the driver unet E1000_RXD_STAT_DD (rxdp->status = 0; ), but sometimes rxdp->status remains equal to 7. On the next cycle, this this buffer is read, RDT moved to far. RDH becomes equal RDT and network is freezes.
+
+If I insert some delay after unset E1000_RXD_STAT_DD, and repeatedly unset E1000_RXD_STAT_DD (if rxdp->status == 7 ), then all work fine.
+If check E1000_RXD_STAT_DD without delay, status rxdp->status always valid.
+
+This only appears on kvm. If I use tcg all works fine.
+
+I trying set watchpoint for memory on the qemu (for tcg), and see, that for one package cycle of set/unse STAT_DD repeated once.
+
+I trying set watchpoint for memory on the qemu (for kvm), and see, that rxdp->status changed to 0(unset) only once, but is changes immediately before set flag. 
+
+
+Please help me with advice on how to catch and fix this error. 
+Theoretically, it would help me to trace the memory access when writing to E1000_RXD_STAT_DD, RHD and RDT, both from the target and the host system. But I have no idea how this can be done.
+
+The QEMU project is currently considering to move its bug tracking to
+another system. For this we need to know which bugs are still valid
+and which could be closed already. Thus we are setting older bugs to
+"Incomplete" now.
+
+If you still think this bug report here is valid, then please switch
+the state back to "New" within the next 60 days, otherwise this report
+will be marked as "Expired". Or please mark it as "Fix Released" if
+the problem has been solved with a newer version of QEMU already.
+
+Thank you and sorry for the inconvenience.
+
+
+[Expired for QEMU because there has been no activity for 60 days.]
+