On 08/23/2018 06:41 PM, Greg Kroah-Hartman wrote:
>> 4.14-stable review patch. If anyone has any objections, please let me know. >> >> ------------------ >> >> From: Sergei Shtylyov sergei.shtylyov@cogentembedded.com >> >> commit a5fb9fb023a1435f2b42bccd7f547560f3a21dc3 upstream. >> >> 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. >> >> Introduce the devm_pci_remap_iospace() managed API and replace the >> pci_remap_iospace() call with it to fix the bug. >> >> Fixes: dbf9826d5797 ("PCI: generic: Convert to DT resource parsing API") >> Signed-off-by: Sergei Shtylyov sergei.shtylyov@cogentembedded.com >> [lorenzo.pieralisi@arm.com: split commit/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 >> [Backport just for the new api which other patches need - gregkh] >> Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org >> >> --- >> drivers/pci/pci.c | 38 ++++++++++++++++++++++++++++++++++++++ >> include/linux/pci.h | 2 ++ >> 2 files changed, 40 insertions(+) > > You missed a chnage to drivers/pci/host/pci-host-common.c (and > also drivers/pci/host/pcie-rcar.c which wasn't using the generic mode back
s/mode/code/, of course. :-)
> then)...
Yes I totally messed this up, let me fix it...
Ok, below is the patch that I replaced the 4.14 and 4.9 versions with, it should now be resolved, but verifying this would be nice :)
Unfortunately, it doesn't fix anything on R-Car where this bug was originally encountered and the fix was tested... and you leave no way for it to be fixed. :-(
Really? Why not? What is missing here?
You just need to fix drivers/pci/host/pcie-rcar.c in this same patch -- because this same *upstream* patch fixed the R-Car PCIe driver in 4.18. That driver started using the common "PCI-resource-walker" function factored out from pci-host-common.c somewhere around 4.17, IIRC...
Ok, can you send me a patch that does that please? Otherwise I really don't know how to exactly "fix" that at the moment.
I'd told you I could do it. :-) Sending...
thanks,
greg k-h
MBR, Sergei