From 0fe58fc54fb17707ba5ff04bcf7c8a5174784bec Mon Sep 17 00:00:00 2001 From: Zdenek Kabelac Date: Fri, 2 Oct 2020 17:42:50 +0200 Subject: [PATCH] bcache: fix busy loop with too many errors When bcache tries to write data to a faulty device, it may get out of caching blocks and then just busy-loops on a CPU - so this check protects this by checking if there is already max_io (~64) errored blocks. --- WHATS_NEW | 1 + lib/device/bcache.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/WHATS_NEW b/WHATS_NEW index bebd1f5cf..1d38a7360 100644 --- a/WHATS_NEW +++ b/WHATS_NEW @@ -1,5 +1,6 @@ Version 2.03.11 - ================================== + Fix bcache when device has too many failing writes. Fix bcache waiting for IO completion with failing disks. Configure use own python path name order to prefer using python3. Add configure --enable-editline support as an alternative to readline. diff --git a/lib/device/bcache.c b/lib/device/bcache.c index 33d124229..3fb6a0e80 100644 --- a/lib/device/bcache.c +++ b/lib/device/bcache.c @@ -964,6 +964,11 @@ static struct block *_new_block(struct bcache *cache, int di, block_address i, b if (dm_list_empty(&cache->io_pending)) _writeback(cache, 16); // FIXME: magic number _wait_all(cache); + if (dm_list_size(&cache->errored) >= cache->max_io) { + log_debug("bcache no new blocks for di %d index %u with >%d errors.", + di, (uint32_t) i, cache->max_io); + return NULL; + } } else { log_debug("bcache no new blocks for di %d index %u", di, (uint32_t) i);