On 06/19/2012 05:00 PM, Andrew Morton wrote: > On Tue, 19 Jun 2012 22:35:08 +0000 > "Pearson, Greg" <greg.pearson@xxxxxx> wrote: > >> On 06/19/2012 04:14 PM, Andrew Morton wrote: >>> On Mon, 18 Jun 2012 17:47:58 -0600 >>> Greg Pearson <greg.pearson@xxxxxx> wrote: >>> >>>> The __alloc_memory_core_early() routine will ask memblock for a range >>>> of memory then try to reserve it. If the reserved region array lacks >>>> space for the new range, memblock_double_array() is called to allocate >>>> more space for the array. If memblock is used to allocate memory for >>>> the new array it can end up using a range that overlaps with the range >>>> originally allocated in __alloc_memory_core_early(), leading to possible >>>> data corruption. >>> OK, but we have no information about whether it *does* lead to data >>> corruption. Are there workloads which trigger this? End users who are >>> experiencing problems? >>> >>> See, I (and others) need to work out whether this patch should be >>> included in 3.5 or even earlier kernels. To do that we often need the >>> developer to tell us what the impact of the bug is upon users. Please >>> always include this info when fixing bugs. >> Andrew, >> >> I'm currently working on a prototype system that exhibits the data >> corruption problem when doubling the reserved array while booting the >> system. This system will be a released product in the future. > OK. I guess we can slip this fix into 3.5. Do you think it should be > backported? I guess "yes", as you will probably want to run 3.4 or > earlier kernels on that machine. > Having the fix in 3.4 would be good for us, as we do plan to test on the latest stable kernel. If there is anything I can do to help with that please let me know. Thanks -- Greg -- 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