Hello Dave and everyone, On Wed, Nov 03, 2010 at 01:43:25PM -0700, Dave Hansen wrote: > Hey Miklos, > > When testing with a transparent huge page kernel: > > http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/andrea/aa.git;a=summary > > some IBM testers ran into some deadlocks. It appears that the > khugepaged process is trying to migrate one of a filesystem daemon's > pages while khugepaged holds the daemon's mmap_sem for write. The allocation under mmap_sem write mode in khugepaged bug should be fixed in current aa.git based on 37-rc5: http://git.kernel.org/?p=linux/kernel/git/andrea/aa.git;a=shortlog http://git.kernel.org/?p=linux/kernel/git/andrea/aa.git;a=commit;h=83e4d55d0014b3eeb982005d73f55ffcf2813504 Let me know how it goes, it's not very well tested yet (which is why I didn't make a new submit yet). I stick to my idea this is bug in userland and may trigger if your daemon does mmap/munmap and the vma allocation under mmap_sem waits for the I/O, but I don't want to show it with THP enabled, and this is more scalable so it's definitely good idea and no downside whatsoever. Thanks for the report, Andrea -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>