On 04/02/2019 03:17 PM, Jan Harkes wrote: > On Sun, Mar 31, 2019 at 03:13:47PM -0400, Jan Harkes wrote: >> On Sun, Mar 31, 2019 at 02:14:13PM -0400, Waiman Long wrote: >>> One possibility is that there is a previous reference to the memory >>> currently occupied by the spinlock. If the memory location is previously >>> part of a rwsem structure and someone is still using it, you may get >>> memory corruption. >> Ah, I hadn't even thought of that possibility. Good, it will open up > First of all, I have to thank you for your original patch because > otherwise I probably would never have discovered that something was > seriously wrong. Your patch made the problem visible. > > I ended up changing 'owner' to '_RET_IP_' and dumping the value of the > clobbered coda inode spinlock and surrounding memory and found that the > 'culprit' is in ext4_filemap_fault and despite it being in ext4, it is > still a Coda specific problem.
It is good news that you have found the bug. However, I don't have sufficient expertise in the filesystem and mm areas to give you recommendation of what to do next. Cheers, Longman
