fcf2959da6
It could happen two kworkers race with each other:
CPU0 CPU1
addr_resolver kworker reconnect kworker
rtrs_clt_rdma_cm_handler
rtrs_rdma_addr_resolved
create_con_cq_qp: s.dev_ref++
"s.dev_ref is 1"
wait in create_cm fails with TIMEOUT
destroy_con_cq_qp: --s.dev_ref
"s.dev_ref is 0"
destroy_con_cq_qp: sess->s.dev = NULL
rtrs_cq_qp_create -> create_qp(con, sess->dev->ib_pd...)
sess->dev is NULL, panic.
To fix the problem using mutex to serialize create_con_cq_qp and
destroy_con_cq_qp.
Fixes: 6a98d71daea1 ("RDMA/rtrs: client: main functionality")
Link: https://lore.kernel.org/r/20201023074353.21946-4-jinpu.wang@cloud.ionos.com
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.