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| author | Andrea Parri (Microsoft) <parri.andrea@gmail.com> | 2022-05-12 01:32:07 +0300 |
|---|---|---|
| committer | Wei Liu <wei.liu@kernel.org> | 2022-05-13 19:57:32 +0300 |
| commit | b4927bd272623694314f37823302f9d67aa5964c (patch) | |
| tree | d71d5b64658c4c6314ace1bd460e68358eb4741e /drivers/pci | |
| parent | 9937fa6d1eb6fac95586970e17617a718919c858 (diff) | |
| download | linux-b4927bd272623694314f37823302f9d67aa5964c.tar.xz | |
PCI: hv: Fix synchronization between channel callback and hv_pci_bus_exit()
[ Similarly to commit a765ed47e4516 ("PCI: hv: Fix synchronization
between channel callback and hv_compose_msi_msg()"): ]
The (on-stack) teardown packet becomes invalid once the completion
timeout in hv_pci_bus_exit() has expired and hv_pci_bus_exit() has
returned. Prevent the channel callback from accessing the invalid
packet by removing the ID associated to such packet from the VMbus
requestor in hv_pci_bus_exit().
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20220511223207.3386-3-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/controller/pci-hyperv.c | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c index a06e2cf94658..db814f7b93ba 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -3664,6 +3664,7 @@ free_bus: static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs) { struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); + struct vmbus_channel *chan = hdev->channel; struct { struct pci_packet teardown_packet; u8 buffer[sizeof(struct pci_message)]; @@ -3671,13 +3672,14 @@ static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs) struct hv_pci_compl comp_pkt; struct hv_pci_dev *hpdev, *tmp; unsigned long flags; + u64 trans_id; int ret; /* * After the host sends the RESCIND_CHANNEL message, it doesn't * access the per-channel ringbuffer any longer. */ - if (hdev->channel->rescind) + if (chan->rescind) return 0; if (!keep_devs) { @@ -3714,16 +3716,26 @@ static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs) pkt.teardown_packet.compl_ctxt = &comp_pkt; pkt.teardown_packet.message[0].type = PCI_BUS_D0EXIT; - ret = vmbus_sendpacket(hdev->channel, &pkt.teardown_packet.message, - sizeof(struct pci_message), - (unsigned long)&pkt.teardown_packet, - VM_PKT_DATA_INBAND, - VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + ret = vmbus_sendpacket_getid(chan, &pkt.teardown_packet.message, + sizeof(struct pci_message), + (unsigned long)&pkt.teardown_packet, + &trans_id, VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); if (ret) return ret; - if (wait_for_completion_timeout(&comp_pkt.host_event, 10 * HZ) == 0) + if (wait_for_completion_timeout(&comp_pkt.host_event, 10 * HZ) == 0) { + /* + * The completion packet on the stack becomes invalid after + * 'return'; remove the ID from the VMbus requestor if the + * identifier is still mapped to/associated with the packet. + * + * Cf. hv_pci_onchannelcallback(). + */ + vmbus_request_addr_match(chan, trans_id, + (unsigned long)&pkt.teardown_packet); return -ETIMEDOUT; + } return 0; } |