• Gavin Shan's avatar
    pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts · 81bd2955
    Gavin Shan authored
    commit 303529d6 upstream.
    
    The root port or PCIe switch downstream port might have been associated
    with driver other than pnv-php. The MSI or MSIx might also have been
    enabled by that driver (e.g. pcieport_drv). Attempt to enable MSI incurs
    below backtrace:
    
     PowerPC PowerNV PCI Hotplug Driver version: 0.1
     ------------[ cut here ]------------
     WARNING: CPU: 19 PID: 1004 at drivers/pci/msi.c:1071 \
                                  __pci_enable_msi_range+0x84/0x4e0
     NIP [c000000000665c34] __pci_enable_msi_range+0x84/0x4e0
     LR [c000000000665c24] __pci_enable_msi_range+0x74/0x4e0
     Call Trace:
     [c000000384d67600] [c000000000665c24] __pci_enable_msi_range+0x74/0x4e0
     [c000000384d676e0] [d00000000aa31b04] pnv_php_register+0x564/0x5a0 [pnv_php]
     [c000000384d677c0] [d00000000aa31658] pnv_php_register+0xb8/0x5a0 [pnv_php]
     [c000000384d678a0] [d00000000aa31658] pnv_php_register+0xb8/0x5a0 [pnv_php]
     [c000000384d67980] [d00000000aa31dfc] pnv_php_init+0x60/0x98 [pnv_php]
     [c000000384d679f0] [c00000000000cfdc] do_one_initcall+0x6c/0x1d0
     [c000000384d67ab0] [c000000000b92354] do_init_module+0x94/0x254
     [c000000384d67b40] [c00000000019719c] load_module+0x258c/0x2c60
     [c000000384d67d30] [c000000000197bb0] SyS_finit_module+0xf0/0x170
     [c000000384d67e30] [c00000000000b184] system_call+0x38/0xe0
    
    This fixes the issue by skipping enabling the surprise hotplug
    capability if the MSI or MSIx on the PCI slot's upstream port has
    been enabled by other driver.
    
    Fixes: 360aebd8 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
    Signed-off-by: default avatarGavin Shan <gwshan@linux.vnet.ibm.com>
    Reviewed-by: default avatarAndrew Donnellan <andrew.donnellan@au1.ibm.com>
    Tested-by: default avatarVaibhav Jain <vaibhav@linux.vnet.ibm.com>
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    81bd2955
pnv_php.c 22.3 KB