[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Fatal crash on xen4.2 HVM + qemu-xen dm + NFS



Ian,

--On 22 January 2013 10:05:16 +0000 Ian Campbell <Ian.Campbell@xxxxxxxxxx> wrote:

I've never looked inside xen_qdisk so I can't really advise, but that
sound broadly correct, except you'd want to use gnttab_copy not mmap
+memcpy. e.g. (totally making up the API because I'm too lazy to go
look):
        buffer = malloc(SIZE)
        if (writing)
                gnttab_copy_from(buffer, gntref, size)

        io->buffer = buffer
        submit(io)
... wait for completion:
        if (reading)
                gnttab_copy_to(...)
        free(io->buffer)

Hopefully you get the idea ;-) Sounds like before the ... goes in
ioreq_map and after the ... goes in ioreq_unmap.

Thanks. If the O_DIRECT thing doesn't fix it, I'll take a look again.
My initial analysis was that a copy interface wasn't available through
xc_ type functions.

--
Alex Bligh

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.