On Wed, Apr 17, 2013 at 02:42:51PM +0800, Simon Jeons wrote: > Hi Naoya, > On 04/11/2013 11:23 PM, Naoya Horiguchi wrote: > > On Thu, Apr 11, 2013 at 03:49:16PM +0200, Andi Kleen wrote: > >>> As a result, if the dirty cache includes user data, the data is lost, > >>> and data corruption occurs if an application uses old data. > >> The application cannot use old data, the kernel code kills it if it > >> would do that. And if it's IO data there is an EIO triggered. > >> > >> iirc the only concern in the past was that the application may miss > >> the asynchronous EIO because it's cleared on any fd access. > >> > >> This is a general problem not specific to memory error handling, > >> as these asynchronous IO errors can happen due to other reason > >> (bad disk etc.) > >> > >> If you're really concerned about this case I think the solution > >> is to make the EIO more sticky so that there is a higher chance > >> than it gets returned. This will make your data much more safe, > >> as it will cover all kinds of IO errors, not just the obscure memory > >> errors. > > I'm interested in this topic, and in previous discussion, what I was said > > is that we can't expect user applications to change their behaviors when > > they get EIO, so globally changing EIO's stickiness is not a great approach. > > The user applications will get EIO firstly or get SIG_KILL firstly? That depends on how the process accesses to the error page, so I can't say which one comes first. Thanks, Naoya Horiguchi -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>