From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nicholas A. Bellinger" Subject: [PATCH 2/3] target: Fix interrupt context bug with stats_lock and core_tmr_alloc_req Date: Fri, 6 May 2011 19:54:57 -0700 Message-ID: <1304736898-10830-3-git-send-email-nab@linux-iscsi.org> References: <1304736898-10830-1-git-send-email-nab@linux-iscsi.org> Return-path: In-Reply-To: <1304736898-10830-1-git-send-email-nab@linux-iscsi.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel , linux-scsi , James Bottomley Cc: Linus Torvalds , Christoph Hellwig , Kiran Patil , "Robert W. Love" , FUJITA Tomonori , Bart Van Assche , Hannes Reinecke , Mike Christie , Andy Grover , Nicholas Bellinger List-Id: linux-scsi@vger.kernel.org From: Nicholas Bellinger This patch fixes two bugs wrt to the interrupt context usage of target core with HW target mode drivers. It first converts the usage of struct se_device->stats_lock in transport_get_lun_for_cmd() and core_tmr_lun_reset() to properly use spin_lock_irq() to address an BUG with CONFIG_LOCKDEP_SUPPORT=y enabled. This patch also adds a 'in_interrupt()' check to allow GFP_ATOMIC usage from core_tmr_alloc_req() to fix a 'sleeping in interrupt context' BUG with HW target fabrics that require this logic to function. Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_device.c | 4 ++-- drivers/target/target_core_tmr.c | 7 ++++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index d25e208..fc10ed4 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -150,13 +150,13 @@ out: { struct se_device *dev = se_lun->lun_se_dev; - spin_lock(&dev->stats_lock); + spin_lock_irq(&dev->stats_lock); dev->num_cmds++; if (se_cmd->data_direction == DMA_TO_DEVICE) dev->write_bytes += se_cmd->data_length; else if (se_cmd->data_direction == DMA_FROM_DEVICE) dev->read_bytes += se_cmd->data_length; - spin_unlock(&dev->stats_lock); + spin_unlock_irq(&dev->stats_lock); } /* diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c index 4a10983..59b8b9c 100644 --- a/drivers/target/target_core_tmr.c +++ b/drivers/target/target_core_tmr.c @@ -55,7 +55,8 @@ struct se_tmr_req *core_tmr_alloc_req( { struct se_tmr_req *tmr; - tmr = kmem_cache_zalloc(se_tmr_req_cache, GFP_KERNEL); + tmr = kmem_cache_zalloc(se_tmr_req_cache, (in_interrupt()) ? + GFP_ATOMIC : GFP_KERNEL); if (!(tmr)) { printk(KERN_ERR "Unable to allocate struct se_tmr_req\n"); return ERR_PTR(-ENOMEM); @@ -398,9 +399,9 @@ int core_tmr_lun_reset( printk(KERN_INFO "LUN_RESET: SCSI-2 Released reservation\n"); } - spin_lock(&dev->stats_lock); + spin_lock_irq(&dev->stats_lock); dev->num_resets++; - spin_unlock(&dev->stats_lock); + spin_unlock_irq(&dev->stats_lock); DEBUG_LR("LUN_RESET: %s for [%s] Complete\n", (preempt_and_abort_list) ? "Preempt" : "TMR", -- 1.7.5.1