This is the seventh patchset to fix the use-after-free problem in lockd which we originally discussed back in October. Along the way, Christoph Hellwig mentioned that it would be advantageous to convert lockd to use the kthread API. This patch set first makes that change and then patches it to actually fix the use after free problem. It also fixes a couple of minor bugs in the current lockd implementation.
This patch takes a different approach in fixing the use-after-free than earlier ones. Instead of trying to ensure that lockd stays up until all callbacks complete, this patch tries to just make sure that all RPC's are canceled when lockd is requested to come down. With this change we no longer need to have lockd_down signal lockd, we don't need to do any extra reference counting, and can use the more conventional kthread functions to handle lockd shutdown. I've done some very basic testing and everything seems to work as expected. I've also tested this against the reproducer that I have for the use-after-free problem and this does fix it. I've tried to make this cleanly bisectable, but have only really tested the final result. Many thanks to Trond Myklebust, Chuck Lever, Neil Brown and Christoph Hellwig for their guidance on this. Signed-off-by: Jeff Layton <[EMAIL PROTECTED]> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
