> -----Original Message----- > From: Dexuan Cui > Sent: Tuesday, March 6, 2018 10:22 AM > To: [email protected]; [email protected]; KY Srinivasan > <[email protected]>; > Stephen Hemminger <[email protected]>; [email protected]; > [email protected]; > [email protected] > Cc: [email protected]; [email protected]; > Haiyang Zhang > <[email protected]>; [email protected]; [email protected]; > Michael > Kelley (EOSG) <[email protected]>; Dexuan Cui > <[email protected]>; > [email protected]; Jack Morgenstein <[email protected]> > Subject: [PATCH v3 6/6] PCI: hv: fix 2 hang issues in hv_compose_msi_msg() > > 1. With the patch "x86/vector/msi: Switch to global reservation mode" > (4900be8360), the recent v4.15 and newer kernels always hang for 1-vCPU > Hyper-V VM with SR-IOV. This is because when we reach hv_compose_msi_msg() > by request_irq() -> request_threaded_irq() -> __setup_irq()->irq_startup() > -> __irq_startup() -> irq_domain_activate_irq() -> ... -> > msi_domain_activate() -> ... -> hv_compose_msi_msg(), local irq is > disabled in __setup_irq(). > > Fix this by polling the channel. > > 2. If the host is ejecting the VF device before we reach > hv_compose_msi_msg(), in a UP VM, we can hang in hv_compose_msi_msg() > forever, because at this time the host doesn't respond to the > CREATE_INTERRUPT request. This issue also happens to old kernels like > v4.14, v4.13, etc. > > Fix this by polling the channel for the PCI_EJECT message and > hpdev->state, and by checking the PCI vendor ID. > > Note: actually the above issues also happen to a SMP VM, if > "hbus->hdev->channel->target_cpu == smp_processor_id()" is true. > > Signed-off-by: Dexuan Cui <[email protected]> > Tested-by: Adrian Suhov <[email protected]> > Tested-by: Chris Valean <[email protected]> > Cc: [email protected] > Cc: Stephen Hemminger <[email protected]> > Cc: K. Y. Srinivasan <[email protected]> > Cc: Vitaly Kuznetsov <[email protected]> > Cc: Jack Morgenstein <[email protected]> > --- > drivers/pci/host/pci-hyperv.c | 58 > ++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 57 insertions(+), 1 deletion(-) >
Reviewed-by: Michael Kelley <[email protected]> _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
