[lkml]   [2011]   [Dec]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH v5 4/9] x86-64: Remove kernel.vsyscall64 sysctl
    Andy Lutomirski <luto <at> MIT.EDU> writes:

    > It's unnecessary overhead in code that's supposed to be highly
    > optimized. Removing it allows us to remove one of the two syscall
    > instructions in the vsyscall page.
    > The only sensible use for it is for UML users, and it doesn't fully
    > address inconsistent vsyscall results on UML. The real fix for UML
    > is to stop using vsyscalls entirely.

    UML is not the only use case for this. Anybody who wants to be able to
    trace _all_ system calls (for debugging, ptrace-based sandboxing, or a
    number of other purposes) needs this.

    We either need this back, or need another way to make it possible to
    trace these system calls.

    Apologies for the late reply, I didn't notice this change until it got
    into my distribution's kernel.

    --Matthew Maurer

     \ /
      Last update: 2011-12-05 19:33    [W:0.025 / U:0.556 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site