Hi folks, Willy reported generic/530 had started hanging on his test machines and I've tried to reproduce the problem he reported. While I haven't reproduced the exact hang he's been having, I've found a couple of others while running g/530 in a tight loop on a couple of test machines. The first 3 patches are defensive fixes - the log worker acts as a watchdog, and the issues in patch 2 and 3 were triggered on my testing of g/530 and lead to 30s delays that the log worker watchdog caught. Without the watchdog, these may actually be deadlock triggers. The 4th patch is the one that fixes the problem Willy reported. It is a regression from conversion of the AIL pushing to use non-blocking CIL flushes. It is unknown why this suddenly started showing up on Willy's test machine right now, and why only on that machine, but it is clearly a problem. This patch catches the state that leads to the deadlock and breaks it with an immediate log force to flush any pending iclogs. Version 2: - updated to 5.17-rc7 - tested by Willy. Version 1: - https://lore.kernel.org/linux-xfs/20220307053252.2534616-1-david@xxxxxxxxxxxxx/
