From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57104) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ejijO-0002dc-78 for qemu-devel@nongnu.org; Thu, 08 Feb 2018 04:43:03 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ejijL-0001jb-2O for qemu-devel@nongnu.org; Thu, 08 Feb 2018 04:43:02 -0500 From: Laurent Vivier Date: Thu, 8 Feb 2018 10:42:41 +0100 Message-Id: <20180208094241.13839-1-lvivier@redhat.com> Subject: [Qemu-devel] [PATCH v2] spapr: check smp_threads <= vsmt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-ppc@nongnu.org, David Gibson , Greg Kurz We ignore silently the value of smp_threads when we set the default VSMT value, and if smp_threads is greater than VSMT kernel is going into trouble later. Fixes: 8904e5a750 ("spapr: Adjust default VSMT value for better migration compatibility") Signed-off-by: Laurent Vivier --- Notes: v2: display a specific error message when the default VSMT is used fix subject hw/ppc/spapr.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 32a876be56..11de276cd5 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -2311,6 +2311,12 @@ static void spapr_set_vsmt_mode(sPAPRMachineState *spapr, Error **errp) * overwhelmingly common case in production systems. */ spapr->vsmt = 8; + if (spapr->vsmt < smp_threads) { + error_setg(&local_err, "Cannot support %d threads/core" + " because it must be <= to default VSMT mode (%d)", + smp_threads, spapr->vsmt); + goto out; + } } /* KVM: If necessary, set the SMT mode: */ -- 2.14.3