[PATCH v2 2/7] Documentation/devices.txt: Mark /dev/oldmem obsolete

[Rob Landley]

On 05/28/2013 01:25:25 AM, Zhang Yanfei wrote:
> On 05/28/2013 02:17 PM, Rob Landley wrote:
> > On 05/26/2013 08:54:19 PM, Zhang Yanfei wrote:
> >> 于 2013年05月27日 09:46, HATAYAMA Daisuke 写道:
> >> > (2013/05/26 15:36), Zhang Yanfei wrote:
> >> >> From: Zhang Yanfei <zhangyanfei at cn.fujitsu.com>
> >> >>
> >> >> Signed-off-by: Zhang Yanfei <zhangyanfei at cn.fujitsu.com>
> >> >> Cc: Dave Jones <davej at redhat.com>
> >> >> ---
> >> >>   Documentation/devices.txt |    3 +--
> >> >>   1 files changed, 1 insertions(+), 2 deletions(-)
> >> >>
> >> >> diff --git a/Documentation/devices.txt  
> b/Documentation/devices.txt
> >> >> index 08f01e7..c8e4002 100644
> >> >> --- a/Documentation/devices.txt
> >> >> +++ b/Documentation/devices.txt
> >> >> @@ -100,8 +100,7 @@ Your cooperation is appreciated.
> >> >>            10 = /dev/aio        Asynchronous I/O notification  
> interface
> >> >>            11 = /dev/kmsg        Writes to this come out as  
> printk's, reads
> >> >>                       export the buffered printk records.
> >> >> -         12 = /dev/oldmem    Used by crashdump kernels to  
> access
> >> >> -                    the memory of the kernel that crashed.
> >> >> +         12 = /dev/oldmem    OBSOLETE
> >> >>
> >> >>     1 block    RAM disk
> >> >>             0 = /dev/ram0        First RAM disk
> >> >>
> >> >
> >> > This is the new patch. Looking at other parts of devices.txt,  
> obsolete is
> >> > sometimes used together with unused. I guess obsolete means this  
> is old interface so
> >> > don't use it as much as possible and unused means this is not  
> used at all now.
> >> > You remove old memory interface completely in this patch set, so  
> is it better to add
> >> > unused, too?
> >> >
> >>
> >> Does obsolete also mean "not used anymore"? I don't know. I think  
> we can wait for some native
> >> English speakers to comment on this.
> >
> > Obsolete implies that it shouldn't be used anymore. There are  
> exceptions to everything, of course...
> >
> > (Unused means nothing is using it. If there's still code using it,  
> it's not unused. So yeah unused would imply removed.)
> >
> 
> So, could I just use UNSED to replace OBSOLETE here? Or use  
> "OBSOLETE/UNUSED"?

Obsolete is fine.

Obsolete means it was used at some point, and thus reusing it might  
confuse or conflcit with legacy software. Unused could just mean that  
we left a gap for some reason, it doesn't imply it ever was used.

Explicitly documenting "unused" is kind of silly: all the ones we  
_don't_ document are presumably unused. Obsolete carries with it a very  
mild warning about legacy software, which is presumably why we still  
bother to mention it at all instead of just removing the entry.

(Then again the point was that nothing ever used this interface in the  
first place. Personally I'd just have removed the entry...)

Rob