• Jiang Liu's avatar
    x86, irq, PCI: Keep IRQ assignment for PCI devices during suspend/hibernation · 3eec5952
    Jiang Liu authored
    Now IOAPIC driver dynamically allocates IRQ numbers for IOAPIC pins.
    We need to keep IRQ assignment for PCI devices during suspend/hibernation,
    otherwise it may cause failure of suspend/hibernation due to:
    1) Device driver calls pci_enable_device() to allocate an IRQ number
       and register interrupt handler on the returned IRQ.
    2) Device driver's suspend callback calls pci_disable_device() and
       release assigned IRQ in turn.
    3) Device driver's resume callback calls pci_enable_device() to
       allocate IRQ number again. A different IRQ number may be assigned
       by IOAPIC driver this time.
    4) Now the hardware delivers interrupt to the new IRQ but interrupt
       handler is still registered against the old IRQ, so it breaks
       suspend/hibernation.
    
    To fix this issue, we keep IRQ assignment during suspend/hibernation.
    Flag pci_dev.dev.power.is_prepared is used to detect that
    pci_disable_device() is called during suspend/hibernation.
    Reported-and-Tested-by: default avatarBorislav Petkov <bp@suse.de>
    Signed-off-by: default avatarJiang Liu <jiang.liu@linux.intel.com>
    Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
    Cc: Tony Luck <tony.luck@intel.com>
    Cc: Joerg Roedel <joro@8bytes.org>
    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
    Cc: Bjorn Helgaas <bhelgaas@google.com>
    Cc: Randy Dunlap <rdunlap@infradead.org>
    Cc: Yinghai Lu <yinghai@kernel.org>
    Cc: Grant Likely <grant.likely@linaro.org>
    Cc: Len Brown <lenb@kernel.org>
    Link: http://lkml.kernel.org/r/1407478071-29399-1-git-send-email-jiang.liu@linux.intel.comSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    3eec5952
irq.c 32.6 KB