On Wed, Sep 12, 2012 at 04:26:22PM +0800, Fengguang Wu wrote: > Hi Felipe, > > FYI, there are new smatch warnings show up in > > tree: git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git merge-result-for-greg > head: 23953bde3e4d6aa8780dc054f6ad9882ac63f4f4 > commit: e918fa161f510136fce45a524e934fe20e62c8b1 [66/99] Merge tag 'gadget-for-v3.7' into merge-result-for-greg > > drivers/usb/core/hub.c:2654 usb_get_hub_port_power_state() error: doing dma on the stack ((null)) Smatch prints out a lot of these warnings. I haven't looked at the rules in a while, so maybe there is a bounce buffer somewhere where it detects stack memory and allocates a DMA'able buffer? It would be better if the function documentation for usb_control_msg() said that the *data pointer had to be kmalloc()ed. Also I wonder if Documentation/DMA-API-HOWTO.txt is out of data. Are we allowed to DMA to vmalloc()ed memory yet? regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
