[PATCH 4.14 192/217] PCI: versatile: Fix I/O space page leak

Greg Kroah-Hartman
2018-08-23T08:39:03Z

From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

[ Upstream commit 0018b265adf7e251f90d3ca1c7c0e32e2a0ad262 ]

When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:

kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)

It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.

The Versatile PCI controller driver has the same issue.
Replace pci_remap_iospace() with the devm_ managed version to fix the bug.

Fixes: b7e78170efd4 ("PCI: versatile: Add DT-based ARM Versatile PB PCIe host driver")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
[lorenzo.pieralisi@arm.com: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/pci/host/pci-versatile.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/pci/host/pci-versatile.c
+++ b/drivers/pci/host/pci-versatile.c
@@ -89,7 +89,7 @@ static int versatile_pci_parse_request_o

switch (resource_type(res)) {
case IORESOURCE_IO:
- err = pci_remap_iospace(res, iobase);
+ err = devm_pci_remap_iospace(dev, res, iobase);
if (err) {
dev_warn(dev, "error %d: failed to map resource %pR\n",
err, res);