| Message ID | 20170731233712.12087-5-sthemmin@microsoft.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Mon, 31 Jul 2017 16:37:12 -0700 Stephen Hemminger <stephen@networkplumber.org> wrote: > The setup of MSI with Hyper-V host was sleeping with locks held. > This error is reported when doing SR-IOV hotplug with kernel built with lockdep. > > BUG: sleeping function called from invalid context at kernel/sched/completion.c:93 > in_atomic(): 1, irqs_disabled(): 1, pid: 1405, name: ip > 3 locks held by ip/1405: > #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff976b10bb>] rtnetlink_rcv+0x1b/0x40 > #1: (&desc->request_mutex){+.+...}, at: [<ffffffff970ddd33>] __setup_irq+0xb3/0x720 > #2: (&irq_desc_lock_class){-.-...}, at: [<ffffffff970ddd65>] __setup_irq+0xe5/0x720 > irq event stamp: 3476 > hardirqs last enabled at (3475): [<ffffffff971b3005>] get_page_from_freelist+0x225/0xc90 > hardirqs last disabled at (3476): [<ffffffff978024e7>] _raw_spin_lock_irqsave+0x27/0x90 > softirqs last enabled at (2446): [<ffffffffc05ef0b0>] ixgbevf_configure+0x380/0x7c0 [ixgbevf] > softirqs last disabled at (2444): [<ffffffffc05ef08d>] ixgbevf_configure+0x35d/0x7c0 [ixgbevf] > > The workaround is to poll for host response instead of blocking on > completion. > > Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> This patch is not directly network related. It needs to go through PCI. I will resend the series.
diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c index 415dcc69a502..334c9a7b8991 100644 --- a/drivers/pci/host/pci-hyperv.c +++ b/drivers/pci/host/pci-hyperv.c @@ -50,6 +50,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/pci.h> +#include <linux/delay.h> #include <linux/semaphore.h> #include <linux/irqdomain.h> #include <asm/irqdomain.h> @@ -1159,7 +1160,12 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) goto free_int_desc; } - wait_for_completion(&comp.comp_pkt.host_event); + /* + * Since this function is called with IRQ locks held, can't + * do normal wait for completion; instead poll. + */ + while (!try_wait_for_completion(&comp.comp_pkt.host_event)) + udelay(100); if (comp.comp_pkt.completion_status < 0) { dev_err(&hbus->hdev->device,
The setup of MSI with Hyper-V host was sleeping with locks held. This error is reported when doing SR-IOV hotplug with kernel built with lockdep. BUG: sleeping function called from invalid context at kernel/sched/completion.c:93 in_atomic(): 1, irqs_disabled(): 1, pid: 1405, name: ip 3 locks held by ip/1405: #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff976b10bb>] rtnetlink_rcv+0x1b/0x40 #1: (&desc->request_mutex){+.+...}, at: [<ffffffff970ddd33>] __setup_irq+0xb3/0x720 #2: (&irq_desc_lock_class){-.-...}, at: [<ffffffff970ddd65>] __setup_irq+0xe5/0x720 irq event stamp: 3476 hardirqs last enabled at (3475): [<ffffffff971b3005>] get_page_from_freelist+0x225/0xc90 hardirqs last disabled at (3476): [<ffffffff978024e7>] _raw_spin_lock_irqsave+0x27/0x90 softirqs last enabled at (2446): [<ffffffffc05ef0b0>] ixgbevf_configure+0x380/0x7c0 [ixgbevf] softirqs last disabled at (2444): [<ffffffffc05ef08d>] ixgbevf_configure+0x35d/0x7c0 [ixgbevf] The workaround is to poll for host response instead of blocking on completion. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> --- drivers/pci/host/pci-hyperv.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)