From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Stabellini Subject: [PULL for-2.6 1/1] xenfb: use the correct condition to avoid excessive looping Date: Wed, 20 Apr 2016 12:15:22 +0100 Message-ID: <1461150922-14509-1-git-send-email-sstabellini@kernel.org> References: Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: "Qemu-devel" To: peter.maydell@linaro.org Cc: xen-devel@lists.xensource.com, sstabellini@kernel.org, Wei Liu , qemu-devel@nongnu.org List-Id: xen-devel@lists.xenproject.org From: Wei Liu In commit ac0487e1 ("xenfb.c: avoid expensive loops when prod <= out_cons"), ">=" was used. In fact, a full ring is a legit state. Correct the test to use ">". Reported-by: "Hao, Xudong" Signed-off-by: Wei Liu Tested-by: "Hao, Xudong" Acked-by: Anthony Perard Signed-off-by: Stefano Stabellini --- hw/display/xenfb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c index 40b096a..9866dfd 100644 --- a/hw/display/xenfb.c +++ b/hw/display/xenfb.c @@ -775,7 +775,7 @@ static void xenfb_handle_events(struct XenFB *xenfb) prod = page->out_prod; out_cons = page->out_cons; - if (prod - out_cons >= XENFB_OUT_RING_LEN) { + if (prod - out_cons > XENFB_OUT_RING_LEN) { return; } xen_rmb(); /* ensure we see ring contents up to prod */ -- 1.9.1