lkml.org 
[lkml]   [2019]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: For review: documentation of clone3() system call
Date
* Michael Kerrisk:

> Another difference for the raw clone() system call is that the
> stack argument may be NULL, in which case the child uses a dupli‐
> cate of the parent's stack. (Copy-on-write semantics ensure that
> the child gets separate copies of stack pages when either process
> modifies the stack.) In this case, for correct operation, the
> CLONE_VM option should not be specified. (If the child shares the
> parent's memory because of the use of the CLONE_VM flag, then no
> copy-on-write duplication occurs and chaos is likely to result.)

I think sharing the stack also works with CLONE_VFORK with CLONE_VM, as
long as measures are taken to preserve the return address in a register.

Thanks,
Florian

\
 
 \ /
  Last update: 2019-11-11 16:04    [W:0.438 / U:0.620 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site