• Sergei Shtylyov's avatar
    PCI: designware: Fix I/O space page leak · fd07f5e1
    Sergei Shtylyov authored
    When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
    driver is 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 DesignWare PCIe controller driver has the same issue.
    
    Replace devm_pci_remap_iospace() with a devm_ managed version to fix the
    bug.
    
    Fixes: cbce7900 ("PCI: designware: Make driver arch-agnostic")
    Signed-off-by: default avatarSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
    [lorenzo.pieralisi@arm.com: updated the commit log]
    Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
    Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
    Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    Acked-by: default avatarJingoo Han <jingoohan1@gmail.com>
    fd07f5e1
pcie-designware-host.c 17.9 KB