Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757837Ab1FPMRm (ORCPT ); Thu, 16 Jun 2011 08:17:42 -0400 Received: from relay2.sgi.com ([192.48.179.30]:47384 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757102Ab1FPMO7 (ORCPT ); Thu, 16 Jun 2011 08:14:59 -0400 To: linux-kernel@vger.kernel.org Subject: [PATCH 6/8 v3] x86, UV: remove cpumask_t from the stack Cc: mingo@elte.hu, penberg@kernel.org Message-Id: From: Cliff Wickman Date: Thu, 16 Jun 2011 07:16:12 -0500 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3155 Lines: 94 From: Cliff Wickman Remove the stack-resident cpumask_t from reset_with_ipi() by allocating one per uvhub. Due to the limited size of the stack the potentially huge cpumask_t may cause stack overrun. We haven't seen it happen yet, but we need to make it a practice not to push such structures onto the stack. Diffed against 3.0.0-rc3 Signed-off-by: Cliff Wickman Reviewed-by: Pekka Enberg --- arch/x86/include/asm/uv/uv_bau.h | 1 + arch/x86/platform/uv/tlb_uv.c | 19 +++++++++++++++---- 2 files changed, 16 insertions(+), 4 deletions(-) Index: linux/arch/x86/include/asm/uv/uv_bau.h =================================================================== --- linux.orig/arch/x86/include/asm/uv/uv_bau.h +++ linux/arch/x86/include/asm/uv/uv_bau.h @@ -488,6 +488,7 @@ struct bau_control { struct bau_control *uvhub_master; struct bau_control *socket_master; struct ptc_stats *statp; + cpumask_t *cpumask; unsigned long timeout_interval; unsigned long set_bau_on_time; atomic_t active_descriptor_count; Index: linux/arch/x86/platform/uv/tlb_uv.c =================================================================== --- linux.orig/arch/x86/platform/uv/tlb_uv.c +++ linux/arch/x86/platform/uv/tlb_uv.c @@ -375,13 +375,13 @@ static void reset_with_ipi(struct pnmask int pnode; int apnode; int maskbits; - cpumask_t mask; int sender = bcp->cpu; + cpumask_t *mask = bcp->uvhub_master->cpumask; struct bau_control *smaster = bcp->socket_master; struct reset_args reset_args; reset_args.sender = sender; - cpus_clear(mask); + cpus_clear(*mask); /* find a single cpu for each uvhub in this distribution mask */ maskbits = sizeof(struct pnmask) * BITSPERBYTE; /* each bit is a pnode relative to the partition base pnode */ @@ -391,11 +391,11 @@ static void reset_with_ipi(struct pnmask continue; apnode = pnode + bcp->partition_base_pnode; cpu = pnode_to_first_cpu(apnode, smaster); - cpu_set(cpu, mask); + cpu_set(cpu, *mask); } /* IPI all cpus; preemption is already disabled */ - smp_call_function_many(&mask, do_reset, (void *)&reset_args, 1); + smp_call_function_many(mask, do_reset, (void *)&reset_args, 1); return; } @@ -1696,6 +1696,16 @@ static void make_per_cpu_thp(struct bau_ } /* + * Each uvhub is to get a local cpumask. + */ +static void make_per_hub_cpumask(struct bau_control *hmaster) +{ + int sz = sizeof(cpumask_t); + + hmaster->cpumask = kzalloc_node(sz, GFP_KERNEL, hmaster->osnode); +} + +/* * Initialize all the per_cpu information for the cpu's on a given socket, * given what has been gathered into the socket_desc struct. * And reports the chosen hub and socket masters back to the caller. @@ -1765,6 +1775,7 @@ static int __init summarize_uvhub_socket socket++; socket_mask = (socket_mask >> 1); } + make_per_hub_cpumask(hmaster); } return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/