lkml.org 
[lkml]   [2014]   [Sep]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v3 25/29] nios2: Module support
    On 14/9/10 5:25 AM, Valdis.Kletnieks@vt.edu wrote:
    > On Mon, 08 Sep 2014 17:22:36 +0800, Ley Foon Tan said:
    >> This patch adds support for loadable modules.
    >>
    >> Signed-off-by: Ley Foon Tan <lftan@altera.com>
    >
    >> +/*
    >> + * Modules should NOT be allocated with kmalloc for (obvious) reasons.
    >> + * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
    >> + * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
    >> + * addresses in 0xc0000000)
    >> + */
    >
    > That's a nice scary comment to see. :)
    >
    > What's the long-term plan here?
    >

    We would probably need to add the ability to add trampolines in some
    way, though this of course impairs a little performance. Or if the
    default region of vmalloc can be configured to use the same 256MB region
    as the kernel.

    I wonder how MIPS (which has similar same-region call/jump instructions)
    deals with this?

    Chung-Lin



    \
     
     \ /
      Last update: 2014-09-10 10:01    [W:4.023 / U:0.320 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site