Re: Bugs in usb-skeleton.c??? :)

[Sergej Pupykin]

 >> As I understand, USB subsystem uses urb->transfer_buffer directly with
 >> DMA. I see that usb-skeleton.c and (at least) bluez's hci_usb allocates it
 >> without GFP_DMA flag. (skeleton with GFP_KERNEL, bluez with GFP_ATOMIC)

 AvdV> I think GFP_DMA means something different than that you think it means.
 AvdV> GFP_DMA is a bad old hack that means "this is for ISA bus cards to DMA
 AvdV> to/from". Since there are no ISA bus USB controllers... the USB code
 AvdV> doesn't need to use GFP_DMA.

Does kmalloc always allocate pages that can be used in DMA?

I see pci_map_single gives address that incremented later without page
boundary checking. Are allocated pages sequented? (usb-ohci.c)

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