On Mon, Oct 24, 2016 at 06:08:13PM +0200, Roman Pen wrote:
> This patch avoids allocation of kthread structure on a stack, and simply
> uses kmalloc. Allocation on a stack became a huge problem (with memory
> corruption and all other not nice consequences) after the commit 2deb4be28
2deb4be28077 ("x86/dumpstack: When OOPSing, rewind the stack before do_exit()")
Is the normal quoting style.
.gitconfig:
[core]
abbrev = 12
[alias]
one = show -s --pretty='format:%h (\"%s\")'
> by Andy Lutomirski, which rewinds the stack on oops, thus ooopsed kthread
> steps on a garbage memory while completion of task->vfork_done structure
> on the following path:
>
> oops_end()
> rewind_stack_do_exit()
> exit_mm()
> mm_release()
> complete_vfork_done()
>
> Also in this patch two structures 'struct kthread_create_info' and
> 'struct kthread' are merged into one 'struct kthread' and its freeing
> is controlled by a reference counter.
>
> The last reference on kthread is put from a task work, the callback,
> which is invoked from do_exit(). The major thing is that the last
> put is happens *after* completion_vfork_done() is invoked.
>
