On Mon, Oct 09, 2017 at 04:16:20PM +0800, Jia-Ju Bai wrote: > The drivers vt6655 and gma500 call pci_set_power_state under a spinlock, which may sleep. > The function call paths are: > gma_power_begin (acquire the spinlock) (drivers/gpu/drm/gma500/power.c) > gma_resume_pci > pci_set_power_state > __pci_start_power_transition (drivers/pci/pci.c) > msleep --> may sleep > > gma_power_begin (acquire the spinlock) (drivers/gpu/drm/gma500/power.c) > gma_resume_pci > pci_enable_device > pci_enable_device_flags (drivers/pci/pci.c) > do_pci_enable_device > pci_set_power_state > __pci_start_power_transition > msleep --> may sleep > > vt6655_suspend (acquire the spinlock) (drivers/staging/vt6655/device_main.c) > pci_set_power_state > __pci_start_power_transition (drivers/pci/pci.c) > msleep --> may sleep > > To fix these bugs, msleep is replaced with mdelay in __pci_start_power_transition > > These bugs are found by my static analysis tool and my code review. Wait, no, why not fix the callers to not have a spinlock. Those are the only users of these calls that are doing so incorrectly, don't change the PCI core for the fault of 2 broken drivers. thanks, greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
