[PATCH v2] hv_balloon: Fix balloon_probe() and balloon_remove() error handling
From: Shradha Gupta <hidden>
Date: 2022-05-16 04:51:13
Also in:
lkml
Subsystem:
hyper-v/azure core and drivers, the rest · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Linus Torvalds
Add missing cleanup in balloon_probe() if the call to balloon_connect_vsp() fails. Also correctly handle cleanup in balloon_remove() when dm_state is DM_INIT_ERROR because balloon_resume() failed. Signed-off-by: Shradha Gupta <redacted> --- Changes in v2: * Use a goto instead of inline code to handle the cleanup in balloon_probe() * Add a comment in balloon_remove() explaining the cleanup scenario * Add missing disable of page reporting when resume from hibernation fails --- drivers/hv/hv_balloon.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index eee7402cfc02..98fcfb516bbc 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c@@ -1842,7 +1842,7 @@ static int balloon_probe(struct hv_device *dev, ret = balloon_connect_vsp(dev); if (ret != 0) - return ret; + goto connect_error; enable_page_reporting(); dm_device.state = DM_INITIALIZED;
@@ -1861,6 +1861,7 @@ static int balloon_probe(struct hv_device *dev, dm_device.thread = NULL; disable_page_reporting(); vmbus_close(dev->channel); +connect_error: #ifdef CONFIG_MEMORY_HOTPLUG unregister_memory_notifier(&hv_memory_nb); restore_online_page_callback(&hv_online_page);
@@ -1882,12 +1883,21 @@ static int balloon_remove(struct hv_device *dev) cancel_work_sync(&dm->ha_wrk.wrk); kthread_stop(dm->thread); - disable_page_reporting(); - vmbus_close(dev->channel); + + /* + * This is to handle the case when balloon_resume() + * call has failed and some cleanup has been done as + * a part of the error handling. + */ + if (dm_device.state != DM_INIT_ERROR) { + disable_page_reporting(); + vmbus_close(dev->channel); #ifdef CONFIG_MEMORY_HOTPLUG - unregister_memory_notifier(&hv_memory_nb); - restore_online_page_callback(&hv_online_page); + unregister_memory_notifier(&hv_memory_nb); + restore_online_page_callback(&hv_online_page); #endif + } + spin_lock_irqsave(&dm_device.ha_lock, flags); list_for_each_entry_safe(has, tmp, &dm->ha_region_list, list) { list_for_each_entry_safe(gap, tmp_gap, &has->gap_list, list) {
@@ -1948,6 +1958,7 @@ static int balloon_resume(struct hv_device *dev) vmbus_close(dev->channel); out: dm_device.state = DM_INIT_ERROR; + disable_page_reporting(); #ifdef CONFIG_MEMORY_HOTPLUG unregister_memory_notifier(&hv_memory_nb); restore_online_page_callback(&hv_online_page);
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2.17.1