[PATCH blktests v2] tests/block/014: ignore dd error messages

[PATCH blktests v2] tests/block/014: ignore dd error messages

[Damien Le Moal]

The kernel commit de3510e52b0a ("null_blk: fix command timeout
completion handling") fixed null_blk driver to report ETIMEDOUT errors
for IO operations failed with a timeout. This change causes the dd call
in block/014 case to print the following error message:

dd: error reading '/dev/nullb0': Connection timed out

The presence of this message result in a failure of the test case even
without a kernel crash or hang, which is what the block/014 case is
testing. Avoid this failure by ignoring dd error messages using a
redirection of dd stderr to /dev/null.

Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
---

Changes from v1:
* Add Reported-by tag

 tests/block/014 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/block/014 b/tests/block/014
index 370fc3d..04c34fa 100755
--- a/tests/block/014
+++ b/tests/block/014
@@ -34,7 +34,7 @@ test() {
 		# crash or hang.
 		for ((i = 0; i < 100; i++)); do
 			dd if=/dev/nullb0 of=/dev/null bs=4K count=4 \
-				iflag=direct status=none &
+				iflag=direct status=none > /dev/null 2>&1 &
 		done
 		wait
 	done
-- 
2.30.2

Re: [PATCH blktests v2] tests/block/014: ignore dd error messages

[Omar Sandoval]

On Thu, Apr 08, 2021 at 01:39:18PM +0900, Damien Le Moal wrote:
> The kernel commit de3510e52b0a ("null_blk: fix command timeout
> completion handling") fixed null_blk driver to report ETIMEDOUT errors
> for IO operations failed with a timeout. This change causes the dd call
> in block/014 case to print the following error message:
> 
> dd: error reading '/dev/nullb0': Connection timed out
> 
> The presence of this message result in a failure of the test case even
> without a kernel crash or hang, which is what the block/014 case is
> testing. Avoid this failure by ignoring dd error messages using a
> redirection of dd stderr to /dev/null.
> 
> Reported-by: kernel test robot <oliver.sang@intel.com>
> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
> ---
> 
> Changes from v1:
> * Add Reported-by tag
> 
>  tests/block/014 | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Sorry about the delay, I was out for a couple of weeks. Applied.