From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966025AbcAZOYb (ORCPT ); Tue, 26 Jan 2016 09:24:31 -0500 Received: from foss.arm.com ([217.140.101.70]:45588 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965295AbcAZOY2 (ORCPT ); Tue, 26 Jan 2016 09:24:28 -0500 From: Marc Zyngier To: Thomas Gleixner , Jason Cooper Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Ma Jun Subject: [PATCH] irqchip/gic-v3-its: Recompute the number of pages on page size change Date: Tue, 26 Jan 2016 14:24:15 +0000 Message-Id: <1453818255-1289-1-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When the programming of a GITS_BASERn register fails because of an unsupported ITS page size, we retry it with a smaller page size. Unfortunately, we don't recompute the number of allocated ITS pages, indicating the wrong value computed in the original allocation. A convenient fix is to free the pages we allocated, update the page size, and restart the allocation. This will ensure that we always allocate the right amount in the case of a device table, specially if we have to reduce the allocation order to stay within the boundaries of the ITS maximum allocation. Reported-by: Ma Jun Tested-by: Ma Jun Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index e23d1d1..3447549 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -875,6 +875,7 @@ static int its_alloc_tables(const char *node_name, struct its_node *its) } alloc_size = (1 << order) * PAGE_SIZE; +retry_alloc_baser: alloc_pages = (alloc_size / psz); if (alloc_pages > GITS_BASER_PAGES_MAX) { alloc_pages = GITS_BASER_PAGES_MAX; @@ -938,13 +939,16 @@ retry_baser: * size and retry. If we reach 4K, then * something is horribly wrong... */ + free_pages((unsigned long)base, order); + its->tables[i] = NULL; + switch (psz) { case SZ_16K: psz = SZ_4K; - goto retry_baser; + goto retry_alloc_baser; case SZ_64K: psz = SZ_16K; - goto retry_baser; + goto retry_alloc_baser; } } -- 2.1.4