From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shanker Donthineni , Marc Zyngier , Hanjun Guo Subject: [PATCH 4.4 46/60] irqchip/gicv3-its: Avoid cache flush beyond ITS_BASERn memory size Date: Thu, 13 Sep 2018 15:30:53 +0200 Message-Id: <20180913131747.607156056@linuxfoundation.org> In-Reply-To: <20180913131745.261413581@linuxfoundation.org> References: <20180913131745.261413581@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shanker Donthineni commit 2eca0d6ceea1f108b2d3ac81fb34698c4fd41006 upstream. Function its_alloc_tables() maintains two local variables, "order" and and "alloc_size", to hold memory size that has been allocated to ITS_BASEn. We don't always refresh the variable alloc_size whenever value of the variable order changes, causing the following two problems. - Cache flush operation with size more than required. - Information reported by pr_info is not correct. Use a helper macro that converts page order to size in bytes instead of variable "alloc_size" to fix both the problems. Signed-off-by: Shanker Donthineni Signed-off-by: Marc Zyngier Signed-off-by: Hanjun Guo Signed-off-by: Greg Kroah-Hartman --- drivers/irqchip/irq-gic-v3-its.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -80,6 +80,9 @@ struct its_node { #define ITS_ITT_ALIGN SZ_256 +/* Convert page order to size in bytes */ +#define PAGE_ORDER_TO_SIZE(o) (PAGE_SIZE << (o)) + struct event_lpi_map { unsigned long *lpi_map; u16 *col_map; @@ -855,7 +858,6 @@ static int its_alloc_tables(const char * u64 type = GITS_BASER_TYPE(val); u64 entry_size = GITS_BASER_ENTRY_SIZE(val); int order = get_order(psz); - int alloc_size; int alloc_pages; u64 tmp; void *base; @@ -887,9 +889,8 @@ static int its_alloc_tables(const char * } } - alloc_size = (1 << order) * PAGE_SIZE; retry_alloc_baser: - alloc_pages = (alloc_size / psz); + alloc_pages = (PAGE_ORDER_TO_SIZE(order) / psz); if (alloc_pages > GITS_BASER_PAGES_MAX) { alloc_pages = GITS_BASER_PAGES_MAX; order = get_order(GITS_BASER_PAGES_MAX * psz); @@ -942,7 +943,7 @@ retry_baser: shr = tmp & GITS_BASER_SHAREABILITY_MASK; if (!shr) { cache = GITS_BASER_nC; - __flush_dcache_area(base, alloc_size); + __flush_dcache_area(base, PAGE_ORDER_TO_SIZE(order)); } goto retry_baser; } @@ -975,7 +976,7 @@ retry_baser: } pr_info("ITS: allocated %d %s @%lx (psz %dK, shr %d)\n", - (int)(alloc_size / entry_size), + (int)(PAGE_ORDER_TO_SIZE(order) / entry_size), its_base_type_string[type], (unsigned long)virt_to_phys(base), psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT);