Messages in this thread | | | From | Dexuan Cui <> | Subject | RE: [PATCH] PCI: hv: Fix a __local_bh_enable_ip warning in hv_compose_msi_msg() | Date | Thu, 7 Jun 2018 00:14:39 +0000 |
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> From: Haiyang Zhang > Sent: Friday, May 25, 2018 12:52 > To: Dexuan Cui <decui@microsoft.com>; Lorenzo Pieralisi > <lorenzo.pieralisi@arm.com>; Bjorn Helgaas <bhelgaas@google.com>; > linux-pci@vger.kernel.org; KY Srinivasan <kys@microsoft.com>; Stephen > Hemminger <sthemmin@microsoft.com>; olaf@aepfle.de; > apw@canonical.com; jasowang@redhat.com > Cc: linux-kernel@vger.kernel.org; driverdev-devel@linuxdriverproject.org; > vkuznets@redhat.com; marcelo.cerri@canonical.com > Subject: RE: [PATCH] PCI: hv: Fix a __local_bh_enable_ip warning in > hv_compose_msi_msg() > > > From: Dexuan Cui > > Sent: Tuesday, May 22, 2018 8:18 PM > > To: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>; Bjorn Helgaas > > <bhelgaas@google.com>; linux-pci@vger.kernel.org; KY Srinivasan > > <kys@microsoft.com>; Stephen Hemminger <sthemmin@microsoft.com>; > > olaf@aepfle.de; apw@canonical.com; jasowang@redhat.com > > Cc: linux-kernel@vger.kernel.org; driverdev-devel@linuxdriverproject.org; > > Haiyang Zhang <haiyangz@microsoft.com>; vkuznets@redhat.com; > > marcelo.cerri@canonical.com > > Subject: [PATCH] PCI: hv: Fix a __local_bh_enable_ip warning in > > hv_compose_msi_msg() > > > > > > Commit de0aa7b2f97d ("PCI: hv: Fix 2 hang issues in > hv_compose_msi_msg()") > > uses local_bh_disable()/enable(), because hv_pci_onchannelcallback() can > also > > run in tasklet context as the channel event callback. > > > > With CONFIG_PROVE_LOCKING=y in the latest mainline, or old kernels that > > don't have commit f71b74bca637 ("irq/softirqs: Use lockdep to assert IRQs > are > > disabled/enabled"), it turns out can we trigger a warning at the beginning of > > __local_bh_enable_ip(), because the upper layer irq code can call > > hv_compose_msi_msg() with local irqs disabled. > > > > Let's fix the warning by switching to local_irq_save()/restore(). This is not an > > issue because hv_pci_onchannelcallback() is not slow, and it not a hot path. > > > > Fixes: de0aa7b2f97d ("PCI: hv: Fix 2 hang issues in hv_compose_msi_msg()") > > Signed-off-by: Dexuan Cui <decui@microsoft.com> > > Cc: <stable@vger.kernel.org> > > Cc: Stephen Hemminger <sthemmin@microsoft.com> > > Cc: K. Y. Srinivasan <kys@microsoft.com> > > --- > > Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> > > Thanks you.
Hi Lorenzo,
Can I have your reply to this patch?
-- Dexuan
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