在 2021/9/30 19:01, Ferruh Yigit 写道:
On 9/30/2021 11:54 AM, Huisong Li wrote:在 2021/9/28 15:19, Singh, Aman Deep 写道:On 9/22/2021 9:01 AM, Huisong Li wrote:在 2021/9/20 22:07, Ferruh Yigit 写道:On 8/25/2021 10:53 AM, Huisong Li wrote:在 2021/8/24 22:42, Ferruh Yigit 写道:On 8/19/2021 4:45 AM, Huisong Li wrote:在 2021/8/18 19:24, Ferruh Yigit 写道:On 8/13/2021 9:16 AM, Huisong Li wrote:在 2021/8/13 14:12, Thomas Monjalon 写道:13/08/2021 04:11, Huisong Li:Hi, all This patch can enhance the security of device uninstallation to eliminate dependency on user usage methods. Can you check this patch? 在 2021/8/3 10:30, Huisong Li 写道:Ethernet devices in DPDK can be released by rte_eth_dev_close() and rte_dev_remove(). These APIs both call xxx_dev_close() in PMD layer to uninstall hardware. However, the two APIs do not have explicit invocation restrictions. In other words, at the ethdev layer, it is possible to call rte_eth_dev_close() before calling rte_dev_remove() or rte_eal_hotplug_remove(). In such a bad scenario,It is not a bad scenario. If there is no more port for the device after calling close, the device should be removed automatically. Keep in mind "close" is for one port, "remove" is for the entire device which can have more than one port.I know. dev_close() is for removing an eth device. And rte_dev_remove() can be used for removing the rte device and all its eth devices belonging to the rte device. In rte_dev_remove(), "remove" is executed in primary or one of secondary, all eth devices having same pci address will be closed and removed.the primary process may be fine, but it may cause that xxx_dev_close() in the PMD layer will be called twice in the secondary process. So this patch fixes it.If a port is closed in primary, it should be the same in secondary.+ /* + * The eth_dev->data->name doesn't be cleared by the secondary process, + * so above "eth_dev" isn't NULL after rte_eth_dev_close() called.This assumption is not clear. All should be closed together.However, dev_close() does not have the feature similar to rte_dev_remove(). Namely, it is not guaranteed that all eth devices are closed together in ethdev layer. It depends on app or user. If the app does not close together, the operation of repeatedly uninstalling an eth device in the secondary process will be triggered when dev_close() is first called by one secondary process, and then rte_dev_remove() is called. So I think it should be avoided.First of all, I am not sure about calling 'rte_eth_dev_close()' or 'rte_dev_remove()' from the secondary process. There are explicit checks in various locations to prevent clearing resources completely from secondary process.There's no denying that. Generally, hardware resources of eth device and shared data of the primary and secondary process are cleared by primary, which are controled by ethdev layer or PMD layer. But there may be some private data or resources of each process (primary or secondary ), such as mp action registered by rte_mp_action_register() or others. For these resources, the secondary process still needs to clear. Namely, both primary and secondary processes need to prevent repeated offloading of resources.Calling 'rte_eth_dev_close()' or 'rte_dev_remove()' by secondary is technically can be done but application needs to be extra cautious and should take extra measures and synchronization to make it work. Regular use-case is secondary processes do the packet processing and all control commands run by primary.You are right. We have a consensus that 'rte_eth_dev_close()' or 'rte_dev_remove()' can be called by primary and secondary processes. But DPDK framework cannot assume user behavior.😁 We need to make it more secure and reliable for both primary and secondary processes.In primary, if you call 'rte_eth_dev_close()' it will clear all ethdev resources and further 'rte_dev_remove()' call will detect missing ethdev resources and won't try to clear them again. In secondary, if you call 'rte_eth_dev_close()', it WON'T clear all resources and further 'rte_dev_remove()' call (either from primary or secondary) will try to clean ethdev resources again. You are trying to prevent this retry in remove happening for secondary process.Right. However, if secondary process in PMD layer has its own private resources to be cleared, it still need to do it by calling 'rte_eth_dev_close()' or 'rte_dev_remove()'.In secondary it won't free ethdev resources anyway if you let it continue, but I guess here you are trying to prevent the PMD dev_close() called again. Why? Is it just for optimization or does it cause unexpected behavior in the PMD? Overall, to free resources you need to do the 'rte_eth_dev_close()' or 'rte_dev_remove()' in the primary anyway. So instead of this workaround, I would suggest making PMD dev_close() safe to be called multiple times (if this is the problem.)In conclusion, primary and secondary processes in PMD layer may have their own private data and resources, which need to be processed and released. Currently, these for PMD are either handled and cleaned up in dev_close() or remove(). However, code streams in rte_dev_remove() cannot ensure that the uninstallation from secondary process will not be repeated if rte_eth_dev_close() is first called by secondary(primary is ok, plese review this patch). I think, this is the same for each PMD and is better suited to doing it in ethdev layer.This patch prevents to call dev_close() twice in the secondary process, is this fixing a theoretical problem or an actual problem? If it is an actual problem can you please provide details, callstack of the problematic case?We analyzed the code when modifying the bug and found that the problem did exist. The ethdev layer did not guarantee the security.I was wondering if there is a crash for an unexpected path, for below case the primary process check in the 'hns3_dev_uninit()' should already prevent anything unexpected. So I assume this is a fix for a theoretical issue.Yes. For primary process, hns3 can prevent multiple device uninstallation through "adapter_state" controled by primary process. The problem of multiple device uninstallation has been prevented at rte_eth_dev_pci_generic_remove() in the ethdev layer, as described in the patch. In primary process, rte_eth_dev_allocated() in rte_eth_dev_pci_generic_remove() will return NULL when first calling dev_close(), and then calling rte_dev_remove(). So it is ok. But the logic can not prevent the same case in secondary because secondary does not clear dev->data.In secondary process, these init/uninit device is already not very safe. For example, as far as I can see in secondary if you hot remove a device device and hot plug a new one, new device will use wrong device data (since hot remove won't clear device data, new one will continue to use it).No. If we hot remove a device in secondary, the secondary will request its primary send "remove device" message to all secondaries. After all secondaries are removed, the primary also removes the device and the device data will be cleared. This is the logic of rte_dev_remove().So I am not sure about adding secondary process related checks in that area and causing a false sense of security, and polluting the logic with secondary specific checks. Also the check you add may hit by primary process and I am worried on an unexpected side affect it cause. As said above I am not sure about this new check, but even we continue with it, what about wrapping the check with secondary process check, at least to be sure there won't be any side affect for primary process.If app hot remove device in primary/secondary, the original logic is still used in this interface, because of bing RTE_ETH_DEV_ATTACHED state for eth_dev. If app first calls dev_close(), eth device is RTE_ETH_DEV_UNUSED state in primary/secondary. In this issue case, this interface is still return from the original place instead of the new check. So I don't think the new check will affect the primary process. Conversely, it's safer for secondary processes. Please check it again, thanks.As this issue is specific to secondary process, can we have these change under a check like "if (rte_eal_process_type() != RTE_PROC_PRIMARY)" By this we can avoid any side effect of these changes for primary process and also it makes code readablity easier for designers who are not checking secondary process changes.yes. @Ferruh, what do you think?+1 to have it, it clarifies the intention of the check, plus prevents possible sice affect for primary as Aman mentioned.
ok. I will modify it in patch V1.
The general function of the two interfaces is as follows: rte_eth_dev_close() --> release eth device rte_dev_remove() --> release eth device + remove and free rte_pci_device(primary andsecondary). According to the OVS application scenario, first call dev_close() and then call remove(), which is possible. We constructed this scenario using testpmd to start the secondary process(the multi-process patch of testpmd is being uploaded.). It is proved that the ethdev layer cannot guarantee this security. The callstack is as follows: ************************************************************************************************************************************************** gdb) set args -a 0000:7d:00.0 -l 2-3 --file-prefix=rte_lee --proc-type=auto -- -i --rxq 4 --txq 4 --num-procs=2 --proc-id=1 (gdb) b hns3_dev_uninit Breakpoint 1 at 0xbca7d0: file ../drivers/net/hns3/hns3_ethdev.c, line 7806. (gdb) b hns3_dev_close Breakpoint 2 at 0xbc6d44: file ../drivers/net/hns3/hns3_ethdev.c, line 6189. (gdb) r Starting program: /home/lihuisong/v500/gcov-test/dpdk/build/app/dpdk-testpmd -a 0000:7d:00.0 -l 2-3 --file-prefix=rte_lee --proc-type=auto -- -i --rxq 4 --txq 4 --num-procs=2 --proc-id=1 Missing separate debuginfo for /root/lib/libnuma.so.1 Try: yum --enablerepo='*debug*' install /usr/lib/debug/.build-id/ce/4eea0b0f2150f70a080bbd8835e43e78373096.debug [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". EAL: Detected 128 lcore(s) EAL: Detected 4 NUMA nodes EAL: Auto-detected process type: SECONDARY EAL: Detected static linkage of DPDK [New Thread 0xfffff7a0ad10 (LWP 17717)] EAL: Multi-process socket /var/run/dpdk/rte_lee/mp_socket_17714_66aa8d3a60a9 [New Thread 0xfffff7209d10 (LWP 17718)] EAL: Selected IOVA mode 'VA' EAL: VFIO support initialized [New Thread 0xfffff69f8d10 (LWP 17719)] EAL: Using IOMMU type 1 (Type 1) EAL: Probe PCI driver: net_hns3 (19e5:a222) device: 0000:7d:00.0 (socket 0) [New Thread 0xfffff61f7d10 (LWP 17720)] TELEMETRY: No legacy callbacks, legacy socket not created Interactive-mode selected 0000:7d:00.0 hns3_dev_mtu_set(): Failed to set mtu, port 0 must be stopped before configuration Failed to set MTU to 1500 for port 0 testpmd: create a new mbuf pool <mb_pool_0>: n=155456, size=2176, socket=0 testpmd: preferred mempool ops selected: ring_mp_mc Warning! port-topology=paired and odd forward ports number, the last port will pair with itself. Configuring Port 0 (socket 0) Port 0: 00:18:2D:00:00:9E Checking link statuses... Done testpmd> port close 0 Closing ports... Breakpoint 2, hns3_dev_close (eth_dev=0x21cdb80 <rte_eth_devices>) at ../drivers/net/hns3/hns3_ethdev.c:6189 6189 struct hns3_adapter *hns = eth_dev->data->dev_private; Missing separate debuginfos, use: debuginfo-install glibc-2.17-260.el7.aarch64 libpcap-1.5.3-11.el7.aarch64 openssl-libs-1.0.2k-16.el7.aarch64 zlib-1.2.7-18.el7.aarch64 (gdb) bt #0 hns3_dev_close (eth_dev=0x21cdb80 <rte_eth_devices>) at ../drivers/net/hns3/hns3_ethdev.c:6189 #1 0x0000000000742eac in rte_eth_dev_close (port_id=0) at ../lib/ethdev/rte_ethdev.c:1870 #2 0x0000000000542a8c in close_port (pid=0) at ../app/test-pmd/testpmd.c:2895 #3 0x00000000004df82c in cmd_operate_specific_port_parsed (parsed_result=0xffffffffb0f0, cl=0x2475080, data=0x0) at ../app/test-pmd/cmdline.c:1272 #4 0x0000000000738ce4 in cmdline_parse (cl=0x2475080, buf=0x24750c8 "port close 0\n") at ../lib/cmdline/cmdline_parse.c:290 #5 0x0000000000736b7c in cmdline_valid_buffer (rdl=0x2475090, buf=0x24750c8 "port close 0\n", size=14) at ../lib/cmdline/cmdline.c:26 #6 0x000000000073c078 in rdline_char_in (rdl=0x2475090, c=10 '\n') at ../lib/cmdline/cmdline_rdline.c:421 #7 0x0000000000736fcc in cmdline_in (cl=0x2475080, buf=0xfffffffff25f "\n\200\362\377\377\377\377", size=1) at ../lib/cmdline/cmdline.c:149 #8 0x0000000000737270 in cmdline_interact (cl=0x2475080) at ../lib/cmdline/cmdline.c:223 #9 0x00000000004f0ccc in prompt () at ../app/test-pmd/cmdline.c:17882 #10 0x0000000000545528 in main (argc=8, argv=0xfffffffff470) at ../app/test-pmd/testpmd.c:3998 (gdb) c Continuing. Port 0 is closed Done testpmd> device detach 0000:7d:00.0 Removing a device... [Switching to Thread 0xfffff7a0ad10 (LWP 17717)] Breakpoint 1, hns3_dev_uninit (eth_dev=0x21cdb80 <rte_eth_devices>) at ../drivers/net/hns3/hns3_ethdev.c:7806 7806 struct hns3_adapter *hns = eth_dev->data->dev_private; (gdb) bt #0 hns3_dev_uninit (eth_dev=0x21cdb80 <rte_eth_devices>) at ../drivers/net/hns3/hns3_ethdev.c:7806 #1 0x0000000000bb8668 in rte_eth_dev_pci_generic_remove (pci_dev=0x247a600, dev_uninit=0xbca7c4 <hns3_dev_uninit>) at ../lib/ethdev/ethdev_pci.h:155 #2 0x0000000000bca89c in eth_hns3_pci_remove (pci_dev=0x247a600) at ../drivers/net/hns3/hns3_ethdev.c:7833 #3 0x00000000007e85f4 in rte_pci_detach_dev (dev=0x247a600) at ../drivers/bus/pci/pci_common.c:287 #4 0x00000000007e8f14 in pci_unplug (dev=0x247a610) at ../drivers/bus/pci/pci_common.c:570 #5 0x0000000000775678 in local_dev_remove (dev=0x247a610) at ../lib/eal/common/eal_common_dev.c:319 #6 0x000000000078f114 in __handle_primary_request (param=0xfffff00008c0) at ../lib/eal/common/hotplug_mp.c:284 #7 0x000000000079ebf4 in eal_alarm_callback (arg=0x0) at ../lib/eal/linux/eal_alarm.c:92 #8 0x00000000007a3f30 in eal_intr_process_interrupts (events=0xfffff7a0a3e0, nfds=1) at ../lib/eal/linux/eal_interrupts.c:998 #9 0x00000000007a4224 in eal_intr_handle_interrupts (pfd=10, totalfds=2) at ../lib/eal/linux/eal_interrupts.c:1071 #10 0x00000000007a442c in eal_intr_thread_main (arg=0x0) at ../lib/eal/linux/eal_interrupts.c:1142 #11 0x0000000000789388 in ctrl_thread_init (arg=0x246ef40) at ../lib/eal/common/eal_common_thread.c:202 #12 0x0000fffff7bf3c48 in start_thread () from /lib64/libpthread.so.0 #13 0x0000fffff7b45600 in thread_start () from /lib64/libc.so.6 ************************************************************************************************************************************************** Note: above log is from the secondary process.And again, please re-consider calling 'rte_eth_dev_close()' or 'rte_dev_remove()' from the secondary process.+ * Namely, whether "eth_dev" is NULL cannot be used to determine whether + * an ethdev port has been released. + * For both primary process and secondary process, eth_dev->state is + * RTE_ETH_DEV_UNUSED, which means the ethdev port has been released. + */ + if (eth_dev->state == RTE_ETH_DEV_UNUSED) { + RTE_ETHDEV_LOG(INFO, "The ethdev port has been released."); + return 0; + }......
