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#ifndef BPF_INSNS_H
#define BPF_INSNS_H

#ifndef BPF_MAXINSNS
# define BPF_MAXINSNS	4096
#endif

#define BPF_CLASS(code) ((code) & 0x07)
#define	BPF_LD		0x00
#define	BPF_LDX		0x01
#define	BPF_ST		0x02
#define	BPF_STX		0x03
#define	BPF_ALU		0x04
#define	BPF_JMP		0x05
#define	BPF_RET		0x06
#define	BPF_MISC	0x07

#define BPF_SIZE(code)	((code) & 0x18)
#define	BPF_W		0x00
#define	BPF_H		0x08
#define	BPF_B		0x10

#define BPF_MODE(code)	((code) & 0xe0)
#define	BPF_IMM 	0x00
#define	BPF_ABS		0x20
#define	BPF_IND		0x40
#define	BPF_MEM		0x60
#define	BPF_LEN		0x80
#define	BPF_MSH		0xa0

#define BPF_OP(code)	((code) & 0xf0)
#define	BPF_ADD		0x00
#define	BPF_SUB		0x10
#define	BPF_MUL		0x20
#define	BPF_DIV		0x30
#define	BPF_OR		0x40
#define	BPF_AND		0x50
#define	BPF_LSH		0x60
#define	BPF_RSH		0x70
#define	BPF_NEG		0x80
#define BPF_MOD		0x90
#define	BPF_XOR		0xa0

#define	BPF_JA		0x00
#define	BPF_JEQ		0x10
#define	BPF_JGT		0x20
#define	BPF_JGE		0x30
#define	BPF_JSET	0x40

#define BPF_SRC(code)	((code) & 0x08)
#define	BPF_K		0x00
#define	BPF_X		0x08

/* ret - BPF_K and BPF_X also apply */
#define BPF_RVAL(code)	((code) & 0x18)
#define	BPF_A		0x10

#define BPF_MISCOP(code) ((code) & 0xf8)
#define	BPF_TAX		0x00
#define	BPF_TXA		0x80

#endif /* BPF_INSNS_H */
quired 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 'drivers/usb/isp1760/isp1760-udc.c')