Il 25/07/2012 15:26, Boaz Harrosh ha scritto: > On 07/25/2012 03:49 PM, Paolo Bonzini wrote: > >> >> Except here the destination array has to be given to virtio, which >> doesn't (yet) understand chaining. I'm using for_each_sg rather than a >> simple memcpy exactly because I want to flatten the input scatterlist >> onto consecutive scatterlist entries, which is what virtio expects (and >> what I'll change when I get to it). >> >> for_each_sg guarantees that I get non-chain scatterlists only, so it is >> okay to value-assign them to sg[]. > > So if the virtio does not understand chaining at all then surly it will > not understand the 2-bit end marker and will get a wrong page pointer > with the 1st bit set. It doesn't understand chaining, but it does use sg_phys(x) so it will not get a wrong page pointer for the end marker. > Fine then your code is now a crash because the terminating bit was just > copied over, which it was not before. I did test the patch with value-assignment. > Lets separate the two topics from now on. Send me one mail concerning > the proper above patch, And a different mail for how to support chaining. Ok, and I'll change the topic. Paolo -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
