On Tue, May 1, 2012 at 2:05 PM, Konstantin Khlebnikov <khlebnikov@xxxxxxxxxx> wrote: > KOSAKI Motohiro wrote: >> >> On Mon, Apr 30, 2012 at 7:29 AM, Konstantin Khlebnikov >> <khlebnikov@xxxxxxxxxx> wrote: >>> >>> This patch adds line "HWPoinson:<size> kB" into /proc/pid/smaps if >>> CONFIG_MEMORY_FAILURE=y and some HWPoison pages were found. >>> This may be useful for searching applications which use a broken memory. >> >> >> I dislike "maybe useful" claim. If we don't know exact motivation of a >> feature, >> we can't maintain them especially when a bugfix can't avoid ABI change. >> >> Please write down exact use case. > > I don't know how to exactly use this hw-poison stuff, but smaps suppose to > export state of ptes in vma. It seems to rational to show also hw-poisoned > ptes, > since kernel has this feature and pte can be in hw-poisoned state. > > and now everyone can easily find them: > # sudo grep HWPoison /proc/*/smaps First, I don't think "we can expose it" is good reason. Second, hw-poisoned mean such process is going to be killed at next page touch. But I can't imagine anyone can use its information because it's racy against process kill. I think admin should use mce log. So, until we find a good use case, I don't ack this. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href