Messages in this thread | | | Date | Wed, 9 May 2012 09:10:15 +1000 | Subject | Re: [PATCH] Describe race of direct read and fork for unaligned buffers | From | Nick Piggin <> |
| |
On 6 May 2012 01:29, KOSAKI Motohiro <kosaki.motohiro@gmail.com> wrote: >> So, am I correct to assume that right text to add to the page is as below? >> >> Nick, can you clarify what you mean by "quiesced"? > > finished?
Yes exactly. That might be a simpler word. Thanks!
> >> >> [[ >> O_DIRECT IOs should never be run concurrently with fork(2) system call, >> when the memory buffer is anonymous memory, or comes from mmap(2) >> with MAP_PRIVATE. >> >> Any such IOs, whether submitted with asynchronous IO interface or from >> another thread in the process, should be quiesced before fork(2) is called. >> Failure to do so can result in data corruption and undefined behavior in >> parent and child processes. >> >> This restriction does not apply when the memory buffer for the O_DIRECT >> IOs comes from mmap(2) with MAP_SHARED or from shmat(2). >> Nor does this restriction apply when the memory buffer has been advised >> as MADV_DONTFORK with madvise(2), ensuring that it will not be available >> to the child after fork(2). >> ]] > > I don't have good English and I can't make editorial check. But at least, > I don't find any technical incorrect explanation here. > > Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |