[PATCH AUTOSEL 4.14 23/89] Drivers: hv: vmbus: Cleanup synic memory free path

From: Sasha Levin
Date: Sun Sep 02 2018 - 09:25:55 EST


From: Michael Kelley <mikelley@xxxxxxxxxxxxx>

[ Upstream commit 572086325ce9a9e348b8748e830653f3959e88b6 ]

clk_evt memory is not being freed when the synic is shutdown
or when there is an allocation error. Add the appropriate
kfree() call, along with a comment to clarify how the memory
gets freed after an allocation error. Make the free path
consistent by removing checks for NULL since kfree() and
free_page() already do the check.

Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/hv/hv.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 8267439dd1ee..d8101cd28dfa 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -196,6 +196,10 @@ int hv_synic_alloc(void)

return 0;
err:
+ /*
+ * Any memory allocations that succeeded will be freed when
+ * the caller cleans up by calling hv_synic_free()
+ */
return -ENOMEM;
}

@@ -208,12 +212,10 @@ void hv_synic_free(void)
struct hv_per_cpu_context *hv_cpu
= per_cpu_ptr(hv_context.cpu_context, cpu);

- if (hv_cpu->synic_event_page)
- free_page((unsigned long)hv_cpu->synic_event_page);
- if (hv_cpu->synic_message_page)
- free_page((unsigned long)hv_cpu->synic_message_page);
- if (hv_cpu->post_msg_page)
- free_page((unsigned long)hv_cpu->post_msg_page);
+ kfree(hv_cpu->clk_evt);
+ free_page((unsigned long)hv_cpu->synic_event_page);
+ free_page((unsigned long)hv_cpu->synic_message_page);
+ free_page((unsigned long)hv_cpu->post_msg_page);
}

kfree(hv_context.hv_numa_map);
--
2.17.1