#undef TRACE_SYSTEM #define TRACE_SYSTEM spmi #if !defined(_TRACE_SPMI_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_SPMI_H #include #include /* * drivers/spmi/spmi.c */ TRACE_EVENT(spmi_write_begin, TP_PROTO(u8 opcode, u8 sid, u16 addr, u8 len, const u8 *buf), TP_ARGS(opcode, sid, addr, len, buf), TP_STRUCT__entry( __field ( u8, opcode ) __field ( u8, sid ) __field ( u16, addr ) __field ( u8, len ) __dynamic_array ( u8, buf, len + 1 ) ), TP_fast_assign( __entry->opcode = opcode; __entry->sid = sid; __entry->addr = addr; __entry->len = len + 1; memcpy(__get_dynamic_array(buf), buf, len + 1); ), TP_printk("opc=%d sid=%02d addr=0x%04x len=%d buf=0x[%*phD]", (int)__entry->opcode, (int)__entry->sid, (int)__entry->addr, (int)__entry->len, (int)__entry->len, __get_dynamic_array(buf)) ); TRACE_EVENT(spmi_write_end, TP_PROTO(u8 opcode, u8 sid, u16 addr, int ret), TP_ARGS(opcode, sid, addr, ret), TP_STRUCT__entry( __field ( u8, opcode ) __field ( u8, sid ) __field ( u16, addr ) __field ( int, ret ) ), TP_fast_assign( __entry->opcode = opcode; __entry->sid = sid; __entry->addr = addr; __entry->ret = ret; ), TP_printk("opc=%d sid=%02d addr=0x%04x ret=%d", (int)__entry->opcode, (int)__entry->sid, (int)__entry->addr, __entry->ret) ); TRACE_EVENT(spmi_read_begin, TP_PROTO(u8 opcode, u8 sid, u16 addr), TP_ARGS(opcode, sid, addr), TP_STRUCT__entry( __field ( u8, opcode ) __field ( u8, sid ) __field ( u16, addr ) ), TP_fast_assign( __entry->opcode = opcode; __entry->sid = sid; __entry->addr = addr; ), TP_printk("opc=%d sid=%02d addr=0x%04x", (int)__entry->opcode, (int)__entry->sid, (int)__entry->addr) ); TRACE_EVENT(spmi_read_end, TP_PROTO(u8 opcode, u8 sid, u16 addr, int ret, u8 len, const u8 *buf), TP_ARGS(opcode, sid, addr, ret, len, buf), TP_STRUCT__entry( __field ( u8, opcode ) __field ( u8, sid ) __field ( u16, addr ) __field ( int, ret ) __field ( u8, len ) __dynamic_array ( u8, buf, len + 1 ) ), TP_fast_assign( __entry->opcode = opcode; __entry->sid = sid; __entry->addr = addr; __entry->ret = ret; __entry->len = len + 1; memcpy(__get_dynamic_array(buf), buf, len + 1); ), TP_printk("opc=%d sid=%02d addr=0x%04x ret=%d len=%02d buf=0x[%*phD]", (int)__entry->opcode, (int)__entry->sid, (int)__entry->addr, __entry->ret, (int)__entry->len, (int)__entry->len, __get_dynamic_array(buf)) ); TRACE_EVENT(spmi_cmd, TP_PROTO(u8 opcode, u8 sid, int ret), TP_ARGS(opcode, sid, ret), TP_STRUCT__entry( __field ( u8, opcode ) __field ( u8, sid ) __field ( int, ret ) ), TP_fast_assign( __entry->opcode = opcode; __entry->sid = sid; __entry->ret = ret; ), TP_printk("opc=%d sid=%02d ret=%d", (int)__entry->opcode, (int)__entry->sid, ret) ); #endif /* _TRACE_SPMI_H */ /* This part must be outside protection */ #include '>net/dn_route.h
diff options
context:
space:
mode:
authorDouglas Miller <dougmill@linux.vnet.ibm.com>2017-01-28 06:42:20 -0600
committerTejun Heo <tj@kernel.org>2017-01-28 07:49:42 -0500
commit966d2b04e070bc040319aaebfec09e0144dc3341 (patch)
tree4b96156e3d1dd4dfd6039b7c219c9dc4616da52d /include/net/dn_route.h
parent1b1bc42c1692e9b62756323c675a44cb1a1f9dbd (diff)
percpu-refcount: fix reference leak during percpu-atomic transition
percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com> Reviewed-by: Jens Axboe <axboe@fb.com> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Cc: stable@vger.kernel.org # v3.18+
Diffstat (limited to 'include/net/dn_route.h')