Messages in this thread | | | Subject | Re: Bugs in usb-skeleton.c??? :) | From | Sergej Pupykin <> | Date | 13 Jul 2006 16:33:35 +0400 |
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>> 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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