Many PCI host controller drivers aren't prepared to have their devices
unbound from them forcefully (e.g., through /sys/.../<driver>/unbind), as
they don't provide any driver .remove callback, where they'd detach the
root bus, release resources, etc. Keeping the driver built in (i.e., not a
loadable module) is not enough; and providing no .remove callback just
means we don't do any teardown.
To rule out the possibility of unbinding a device via sysfs, we need to set
the ".suppress_bind_attrs" field.
I found the suspect drivers via the following search:
git grep -l platform_driver $(git grep -L -e '\.remove' -e suppress_bind_attrs drivers/pci/)
Then I inspected them to ensure that
(a) they set up a PCI bus in their probe() and
(b) they don't have a remove() callback for undoing the setup
Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
PCI configuration space should be mapped with a memory region type that
generates on the CPU host bus non-posted write transations. Update the
driver to use the devm_pci_remap_cfg* interface to make sure the correct
memory mappings for PCI configuration space are used.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Mingkai Hu <mingkai.hu@freescale.com>
Cc: Minghuan Lian <minghuan.Lian@freescale.com>
Cc: Roy Zang <tie-fei.zang@freescale.com>
Fix the following crash, seen in dwc/pci-imx6.
Unable to handle kernel NULL pointer dereference at virtual address 00000070
pgd = c0004000
[00000070] *pgd=00000000
Internal error: Oops: 805 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.10.0-09686-g9e31489 #1
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
task: cb850000 task.stack: cb84e000
PC is at imx6_pcie_probe+0x2f4/0x414
...
While at it, fix the same problem in various drivers instead of waiting for
individual crash reports.
The change in the imx6 driver was tested with qemu. The changes in other
drivers are based on code inspection and have been compile tested only.
Fixes: 442ec4c04d ("PCI: dwc: all: Split struct pcie_port into host-only and core structures")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> # designware-plat
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
