From: Heiko Carstens Date: Tue, 4 Jul 2006 00:32:21 +0000 (-0700) Subject: [PATCH] zfcp: fix incorrect usage of fsf_req_list_lock X-Git-Tag: v2.6.18-rc1~25 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38c54ee8d5338f49aca986081ea41a987c15cf9d;p=linux-2.6 [PATCH] zfcp: fix incorrect usage of fsf_req_list_lock ================================= [ INFO: inconsistent lock state ] --------------------------------- inconsistent {in-hardirq-W} -> {hardirq-on-W} usage. swapper/0 [HC0[0]:SC1[1]:HE1:SE0] takes: (&adapter->fsf_req_list_lock){++..}, at: [<0000000000274486>] zfcp_qdio_reqid_check+0x46/0x178 {in-hardirq-W} state was registered at: [<000000000005fb0c>] __lock_acquire+0xad8/0xed0 [<00000000000604ae>] lock_acquire+0x9a/0xc8 [<000000000035a326>] _spin_lock+0x4e/0x68 [<0000000000274486>] zfcp_qdio_reqid_check+0x46/0x178 [<000000000027469e>] zfcp_qdio_response_handler+0xe6/0x430 [<0000000000219dd4>] tiqdio_thinint_handler+0xd20/0x213c [<000000000020229a>] do_adapter_IO+0xb2/0xc0 [<0000000000206f32>] do_IRQ+0x136/0x16c [<0000000000020462>] io_no_vtime+0x16/0x1c [<0000000000019432>] cpu_idle+0x222/0x250 irq event stamp: 129220 hardirqs last enabled at (129220): [<00000000000411e6>] tasklet_hi_action+0x5a/0x19c hardirqs last disabled at (129219): [<00000000000411c0>] tasklet_hi_action+0x34/0x19c softirqs last enabled at (129212): [<0000000000040b62>] __do_softirq+0x13a/0x180 softirqs last disabled at (129217): [<000000000001fd58>] do_softirq+0xec/0xf0 other info that might help us debug this: no locks held by swapper/0. stack backtrace: 00000000012bb670 0000000000000002 0000000000000000 00000000012bb780 00000000012bb6e8 0000000000399122 0000000000399122 0000000000016b0a 0000000000000000 0000000000000000 0000000000000000 00000000004660e8 0000000000000000 000000000000000d 00000000012bb6e0 00000000012bb758 0000000000368b90 0000000000016b0a 00000000012bb6e0 00000000012bb730 Call Trace: ([<0000000000016a26>] show_trace+0x76/0xdc) [<0000000000016b2c>] show_stack+0xa0/0xd0 [<0000000000016b8a>] dump_stack+0x2e/0x3c [<000000000005e3da>] print_usage_bug+0x27e/0x290 [<000000000005ea9c>] mark_lock+0x6b0/0x6c0 [<000000000005f33e>] __lock_acquire+0x30a/0xed0 [<00000000000604ae>] lock_acquire+0x9a/0xc8 [<000000000035a326>] _spin_lock+0x4e/0x68 [<0000000000274486>] zfcp_qdio_reqid_check+0x46/0x178 [<000000000027469e>] zfcp_qdio_response_handler+0xe6/0x430 [<0000000000217bd2>] tiqdio_tl+0xd02/0x2120 [<000000000004123a>] tasklet_hi_action+0xae/0x19c [<0000000000040ae4>] __do_softirq+0xbc/0x180 [<000000000001fd58>] do_softirq+0xec/0xf0 [<0000000000040c38>] irq_exit+0x90/0xa8 [<0000000000206f40>] do_IRQ+0x144/0x16c [<0000000000020462>] io_no_vtime+0x16/0x1c [<0000000000019432>] cpu_idle+0x222/0x250 ([<0000000000019416>] cpu_idle+0x206/0x250) [<000000000001405a>] rest_init+0x5a/0x68 [<0000000000536998>] start_kernel+0x39c/0x3dc [<0000000000013046>] _stext+0x46/0x1000 Fix incorrect usage of fsf_req_list_lock. It's used in tasklet context (irqs on) as well as in irq context. Therefore use the spin_lock_irqsave variant to avoid deadlocks. Acked-by: Andreas Herrmann Signed-off-by: Heiko Carstens Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/s390/scsi/zfcp_qdio.c b/drivers/s390/scsi/zfcp_qdio.c index 345a191926..49ea5add4a 100644 --- a/drivers/s390/scsi/zfcp_qdio.c +++ b/drivers/s390/scsi/zfcp_qdio.c @@ -427,6 +427,7 @@ int zfcp_qdio_reqid_check(struct zfcp_adapter *adapter, void *sbale_addr) { struct zfcp_fsf_req *fsf_req; + unsigned long flags; /* invalid (per convention used in this driver) */ if (unlikely(!sbale_addr)) { @@ -438,15 +439,15 @@ zfcp_qdio_reqid_check(struct zfcp_adapter *adapter, void *sbale_addr) fsf_req = (struct zfcp_fsf_req *) sbale_addr; /* serialize with zfcp_fsf_req_dismiss_all */ - spin_lock(&adapter->fsf_req_list_lock); + spin_lock_irqsave(&adapter->fsf_req_list_lock, flags); if (list_empty(&adapter->fsf_req_list_head)) { - spin_unlock(&adapter->fsf_req_list_lock); + spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags); return 0; } list_del(&fsf_req->list); atomic_dec(&adapter->fsf_reqs_active); - spin_unlock(&adapter->fsf_req_list_lock); - + spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags); + if (unlikely(adapter != fsf_req->adapter)) { ZFCP_LOG_NORMAL("bug: invalid reqid (fsf_req=%p, " "fsf_req->adapter=%p, adapter=%p)\n",