From 24b8b44780a2c53ecb738f4a1c08d114f5eda27c Mon Sep 17 00:00:00 2001 From: Tom Tucker Date: Wed, 13 Aug 2008 11:05:41 -0500 Subject: svcrdma: Fix race between svc_rdma_recvfrom thread and the dto_tasklet RDMA_READ completions are kept on a separate queue from the general I/O request queue. Since a separate lock is used to protect the RDMA_READ completion queue, a race exists between the dto_tasklet and the svc_rdma_recvfrom thread where the dto_tasklet sets the XPT_DATA bit and adds I/O to the read-completion queue. Concurrently, the recvfrom thread checks the generic queue, finds it empty and resets the XPT_DATA bit. A subsequent svc_xprt_enqueue will fail to enqueue the transport for I/O and cause the transport to "stall". The fix is to protect both lists with the same lock and set the XPT_DATA bit with this lock held. Signed-off-by: Tom Tucker Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svc_rdma.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index ef2e3a2..dc05b54 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -143,7 +143,6 @@ struct svcxprt_rdma { unsigned long sc_flags; struct list_head sc_dto_q; /* DTO tasklet I/O pending Q */ struct list_head sc_read_complete_q; - spinlock_t sc_read_complete_lock; struct work_struct sc_work; }; /* sc_flags */ -- cgit v1.1