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authorTobias Klauser <tklauser@distanz.ch>2017-05-03 14:33:41 +0200
committerTobias Klauser <tklauser@distanz.ch>2017-05-03 14:33:41 +0200
commita9f4431e0a205617bb316dbe459ac6188dd8b490 (patch)
treefc62c02cfb8372cbcbf378ed1c58d0c33b0c4ffd /xmalloc.c
parenta5a5a91342ebd83d13b8eff8f85d9c923e08f701 (diff)
proc: include headers to get definitions for ino_t and pid_t
Include <unistd.h> and <sys/types.h> in the header already as the declarations for proc_find_by_inode(...) and proc_exists(...) use ino_t and pid_t, respectively. Fixes: 1edfb2409d15 ("flowtop: Move & refactor walk_processes() to proc.c") Fixes: 1df0f481922a ("flowtop: Add process UI tab entry") Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Diffstat (limited to 'xmalloc.c')
0 files changed, 0 insertions, 0 deletions
ic_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/math-emu/single.h')