The 'process_mdb' method has a 4k byte array used for copying data between the guest and the chardev backend. Skip the automatic zero-init of this array to eliminate the performance overhead in the I/O hot path.
The 'buffer' array will be selectively initialized when data is converted between EBCDIC and ASCII. Signed-off-by: Daniel P. Berrangé <berra...@redhat.com> --- hw/char/sclpconsole-lm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/char/sclpconsole-lm.c b/hw/char/sclpconsole-lm.c index e9580aacba..3e40d5e434 100644 --- a/hw/char/sclpconsole-lm.c +++ b/hw/char/sclpconsole-lm.c @@ -214,7 +214,7 @@ static int process_mdb(SCLPEvent *event, MDBO *mdbo) { int rc; int len; - uint8_t buffer[SIZE_BUFFER]; + QEMU_UNINITIALIZED uint8_t buffer[SIZE_BUFFER]; len = be16_to_cpu(mdbo->length); len -= sizeof(mdbo->length) + sizeof(mdbo->type) -- 2.49.0