Re: [Patch v2] PCI: hv: Fix sleep while in non-sleep context when removing child devices from the bus

On Tue, Aug 31, 2021 at 01:16:07PM +0000, Wei Liu wrote:

On Mon, Aug 30, 2021 at 04:13:27PM -0700, longli@linuxonhyperv.com wrote:

quoted

From: Long Li <longli@microsoft.com>

In hv_pci_bus_exit, the code is holding a spinlock while calling
pci_destroy_slot(), which takes a mutex.

This is not safe for spinlock. Fix this by moving the children to be
deleted to a list on the stack, and removing them after spinlock is
released.

Fixes: 94d22763207a ("PCI: hv: Fix a race condition when removing the device")

Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <redacted>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Lorenzo Pieralisi <redacted>
Cc: Rob Herring <robh@kernel.org>
Cc: "Krzysztof Wilczyński" <redacted>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Michael Kelley <redacted>
Reported-by: Dan Carpenter <redacted>
Link: https://lore.kernel.org/linux-hyperv/20210823152130.GA21501@kili/ (local)
Signed-off-by: Long Li <longli@microsoft.com>

Reviewed-by: Wei Liu <wei.liu@kernel.org>

Applied to hyperv-fixes.