From 91203f08f0ca66f1a6aba1d0e5ef62ed98fb3234 Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Fri, 25 Nov 2016 13:27:44 +0200 Subject: [PATCH] qcow2: Allow 'cache-clean-interval' in Linux only The cache-clean-interval option of qcow2 only works on Linux. However we allow setting it in other systems regardless of whether it works or not. In those systems this option is not simply a no-op: it actually invalidates perfectly valid cache tables for no good reason without freeing their memory. This patch forbids using that option in non-Linux systems. Signed-off-by: Alberto Garcia Signed-off-by: Kevin Wolf --- block/qcow2.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/block/qcow2.c b/block/qcow2.c index 7cfcd8412c..ed9e0f31d6 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -668,6 +668,14 @@ static int qcow2_update_options_prepare(BlockDriverState *bs, r->cache_clean_interval = qemu_opt_get_number(opts, QCOW2_OPT_CACHE_CLEAN_INTERVAL, s->cache_clean_interval); +#ifndef CONFIG_LINUX + if (r->cache_clean_interval != 0) { + error_setg(errp, QCOW2_OPT_CACHE_CLEAN_INTERVAL + " not supported on this host"); + ret = -EINVAL; + goto fail; + } +#endif if (r->cache_clean_interval > UINT_MAX) { error_setg(errp, "Cache clean interval too big"); ret = -EINVAL; -- 2.11.0