From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:44962 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725952AbeIREU0 (ORCPT ); Tue, 18 Sep 2018 00:20:26 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Geert Uytterhoeven , Laurent Pinchart , Joerg Roedel , Sasha Levin Subject: [PATCH 4.4 41/56] iommu/ipmmu-vmsa: Fix allocation in atomic context Date: Tue, 18 Sep 2018 00:42:14 +0200 Message-Id: <20180917213829.621814849@linuxfoundation.org> In-Reply-To: <20180917213827.913122591@linuxfoundation.org> References: <20180917213827.913122591@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Geert Uytterhoeven [ Upstream commit 46583e8c48c5a094ba28060615b3a7c8c576690f ] When attaching a device to an IOMMU group with CONFIG_DEBUG_ATOMIC_SLEEP=y: BUG: sleeping function called from invalid context at mm/slab.h:421 in_atomic(): 1, irqs_disabled(): 128, pid: 61, name: kworker/1:1 ... Call trace: ... arm_lpae_alloc_pgtable+0x114/0x184 arm_64_lpae_alloc_pgtable_s1+0x2c/0x128 arm_32_lpae_alloc_pgtable_s1+0x40/0x6c alloc_io_pgtable_ops+0x60/0x88 ipmmu_attach_device+0x140/0x334 ipmmu_attach_device() takes a spinlock, while arm_lpae_alloc_pgtable() allocates memory using GFP_KERNEL. Originally, the ipmmu-vmsa driver had its own custom page table allocation implementation using GFP_ATOMIC, hence the spinlock was fine. Fix this by replacing the spinlock by a mutex, like the arm-smmu driver does. Fixes: f20ed39f53145e45 ("iommu/ipmmu-vmsa: Use the ARM LPAE page table allocator") Signed-off-by: Geert Uytterhoeven Reviewed-by: Laurent Pinchart Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/ipmmu-vmsa.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/drivers/iommu/ipmmu-vmsa.c +++ b/drivers/iommu/ipmmu-vmsa.c @@ -44,7 +44,7 @@ struct ipmmu_vmsa_domain { struct io_pgtable_ops *iop; unsigned int context_id; - spinlock_t lock; /* Protects mappings */ + struct mutex mutex; /* Protects mappings */ }; struct ipmmu_vmsa_archdata { @@ -464,7 +464,7 @@ static struct iommu_domain *ipmmu_domain if (!domain) return NULL; - spin_lock_init(&domain->lock); + mutex_init(&domain->mutex); return &domain->io_domain; } @@ -488,7 +488,6 @@ static int ipmmu_attach_device(struct io struct ipmmu_vmsa_archdata *archdata = dev->archdata.iommu; struct ipmmu_vmsa_device *mmu = archdata->mmu; struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); - unsigned long flags; unsigned int i; int ret = 0; @@ -497,7 +496,7 @@ static int ipmmu_attach_device(struct io return -ENXIO; } - spin_lock_irqsave(&domain->lock, flags); + mutex_lock(&domain->mutex); if (!domain->mmu) { /* The domain hasn't been used yet, initialize it. */ @@ -513,7 +512,7 @@ static int ipmmu_attach_device(struct io ret = -EINVAL; } - spin_unlock_irqrestore(&domain->lock, flags); + mutex_unlock(&domain->mutex); if (ret < 0) return ret;