From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43420) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VbuUr-0004Av-PP for qemu-devel@nongnu.org; Thu, 31 Oct 2013 11:49:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VbuUm-0004Ke-H4 for qemu-devel@nongnu.org; Thu, 31 Oct 2013 11:49:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:22059) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VbuUm-0004KI-7d for qemu-devel@nongnu.org; Thu, 31 Oct 2013 11:49:16 -0400 From: Kevin Wolf Date: Thu, 31 Oct 2013 16:48:28 +0100 Message-Id: <1383234524-372-15-git-send-email-kwolf@redhat.com> In-Reply-To: <1383234524-372-1-git-send-email-kwolf@redhat.com> References: <1383234524-372-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 14/30] ahci: fix win7 hang on boot List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony@codemonkey.ws Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Alexander Graf When AHCI executes an asynchronous IDE command, it checked DRDY without checking either DRQ or BSY. This sometimes caused interrupt to be sent before command is actually completed. This resulted in a race condition: if guest then managed to access the device before command has completed, it would hang waiting for an interrupt. This was observed with windows 7 guests. To fix, check for DRQ or BSY in additiona to DRDY, if set, the command is asynchronous so delay the interrupt until asynchronous done callback is invoked. Reported-by: Michael S. Tsirkin Reviewed-by: Michael S. Tsirkin Tested-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Signed-off-by: Kevin Wolf --- hw/ide/ahci.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c index a8be62c..fbea9e8 100644 --- a/hw/ide/ahci.c +++ b/hw/ide/ahci.c @@ -961,7 +961,8 @@ static int handle_cmd(AHCIState *s, int port, int slot) /* We're ready to process the command in FIS byte 2. */ ide_exec_cmd(&s->dev[port].port, cmd_fis[2]); - if (s->dev[port].port.ifs[0].status & READY_STAT) { + if ((s->dev[port].port.ifs[0].status & (READY_STAT|DRQ_STAT|BUSY_STAT)) == + READY_STAT) { ahci_write_fis_d2h(&s->dev[port], cmd_fis); } } -- 1.8.1.4