[v4,0/5] pci-hyperv: Fix race condition bugs for fast device hotplug

Message ID 20230615044451.5580-1-decui@microsoft.com
Headers
Series pci-hyperv: Fix race condition bugs for fast device hotplug |

Message

Dexuan Cui June 15, 2023, 4:44 a.m. UTC
  Before the guest finishes probing a device, the host may be already starting
to remove the device. Currently there are multiple race condition bugs in the
pci-hyperv driver, which can cause the guest to panic.  The patchset fixes
the crashes.

The patchset also does some cleanup work: patch 3 removes the useless
hv_pcichild_state, and patch 4 reverts an old patch which is not really
useful (without patch 4, it would be hard to make patch 5 clean).

Patch 6 in v3 is dropped for now since it's a feature rather than a fix.
Patch 6 will be split into two patches as suggested by Lorenzo and will be
posted after the 5 patches are accepted first.

The v4 addressed Lorenzo's comments and added Lorenzo' Acks to patch
1, 3 and 5.

The v4 is based on v6.4-rc6, and can apply cleanly to the Hyper-V tree's
hyperv-fixes branch.

The patchset is also availsble in my github branch:
https://github.com/dcui/tdx/commits/decui/vpci/v6.4-rc6-vpci-v4

FYI, v3 can be found here:
https://lwn.net/ml/linux-kernel/20230420024037.5921-1-decui@microsoft.com/

Please review. Thanks!


Dexuan Cui (5):
  PCI: hv: Fix a race condition bug in hv_pci_query_relations()
  PCI: hv: Fix a race condition in hv_irq_unmask() that can cause panic
  PCI: hv: Remove the useless hv_pcichild_state from struct hv_pci_dev
  Revert "PCI: hv: Fix a timing issue which causes kdump to fail
    occasionally"
  PCI: hv: Add a per-bus mutex state_lock

 drivers/pci/controller/pci-hyperv.c | 139 ++++++++++++++++------------
 1 file changed, 82 insertions(+), 57 deletions(-)
  

Comments

Wei Liu June 18, 2023, 3:06 a.m. UTC | #1
On Wed, Jun 14, 2023 at 09:44:46PM -0700, Dexuan Cui wrote:
> Before the guest finishes probing a device, the host may be already starting
> to remove the device. Currently there are multiple race condition bugs in the
> pci-hyperv driver, which can cause the guest to panic.  The patchset fixes
> the crashes.
> 
> The patchset also does some cleanup work: patch 3 removes the useless
> hv_pcichild_state, and patch 4 reverts an old patch which is not really
> useful (without patch 4, it would be hard to make patch 5 clean).
> 
> Patch 6 in v3 is dropped for now since it's a feature rather than a fix.
> Patch 6 will be split into two patches as suggested by Lorenzo and will be
> posted after the 5 patches are accepted first.
> 
> The v4 addressed Lorenzo's comments and added Lorenzo' Acks to patch
> 1, 3 and 5.
> 
> The v4 is based on v6.4-rc6, and can apply cleanly to the Hyper-V tree's
> hyperv-fixes branch.
> 
> The patchset is also availsble in my github branch:
> https://github.com/dcui/tdx/commits/decui/vpci/v6.4-rc6-vpci-v4
> 
> FYI, v3 can be found here:
> https://lwn.net/ml/linux-kernel/20230420024037.5921-1-decui@microsoft.com/
> 
> Please review. Thanks!
> 
> 
> Dexuan Cui (5):
>   PCI: hv: Fix a race condition bug in hv_pci_query_relations()
>   PCI: hv: Fix a race condition in hv_irq_unmask() that can cause panic
>   PCI: hv: Remove the useless hv_pcichild_state from struct hv_pci_dev
>   Revert "PCI: hv: Fix a timing issue which causes kdump to fail
>     occasionally"
>   PCI: hv: Add a per-bus mutex state_lock

Applied to hyperv-fixes. Thanks.