From: Wei Hu <weh@xxxxxxxxxxxxx> Sent: Friday, July 17, 2020 8:48 PM > To: KY Srinivasan <kys@xxxxxxxxxxxxx>; Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>; > Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>; wei.liu@xxxxxxxxxx; > lorenzo.pieralisi@xxxxxxx; robh@xxxxxxxxxx; bhelgaas@xxxxxxxxxx; linux- > hyperv@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Dexuan > Cui <decui@xxxxxxxxxxxxx>; Michael Kelley <mikelley@xxxxxxxxxxxxx> > Cc: Wei Hu <weh@xxxxxxxxxxxxx> > Subject: [PATCH v3] PCI: hv: Fix a timing issue which causes kdump to fail occasionally > > Kdump could fail sometime on Hyper-V guest over Accelerated Network > interface. This is because the retry in hv_pci_enter_d0() relies on > an asynchronous host event arriving before the guest calls > hv_send_resources_allocated(). Fix the problem by moving retry > to hv_pci_probe(), removing this dependency and making the calling > sequence synchronous. > > Fixes: c81992e7f4aa ("PCI: hv: Retry PCI bus D0 entry on invalid device state") > Signed-off-by: Wei Hu <weh@xxxxxxxxxxxxx> > --- > v2: Adding Fixes tag according to Michael Kelley's review comment. > v3: Fix couple typos and reword commit message to make it clearer. > Thanks the comments from Bjorn Helgaas. > > drivers/pci/controller/pci-hyperv.c | 66 ++++++++++++++--------------- > 1 file changed, 32 insertions(+), 34 deletions(-) > I gave my Reviewed-by on the earlier v1 of this patch, but reiterating it here: Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>