[PATCH 1/4] Drivers: hv: vmus: Fix the check for return value from kmsg get dump buffer

From: kys
Date: Sat Jul 28 2018 - 17:59:54 EST


From: Sunil Muthuswamy <sunilmut@xxxxxxxxxxxxx>

The code to support panic control message was checking the return was
checking the return value from kmsg_dump_get_buffer as error value, which
is not what the routine returns. This fixes it.

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")

Signed-off-by: Sunil Muthuswamy <sunilmut@xxxxxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 05e37283d7c3..a7f33c1f42c5 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1047,13 +1047,10 @@ static void hv_kmsg_dump(struct kmsg_dumper *dumper,
* Write dump contents to the page. No need to synchronize; panic should
* be single-threaded.
*/
- if (!kmsg_dump_get_buffer(dumper, true, hv_panic_page,
- PAGE_SIZE, &bytes_written)) {
- pr_err("Hyper-V: Unable to get kmsg data for panic\n");
- return;
- }
-
- hyperv_report_panic_msg(panic_pa, bytes_written);
+ kmsg_dump_get_buffer(dumper, true, hv_panic_page, PAGE_SIZE,
+ &bytes_written);
+ if (bytes_written)
+ hyperv_report_panic_msg(panic_pa, bytes_written);
}

static struct kmsg_dumper hv_kmsg_dumper = {
--
2.17.1