Do following cleanups about braces:
- Add the necessary braces to maintain context alignment.
- Fix the open '{' that is not on the same line as "switch".
- Remove braces that are not necessary for single statement blocks.
- Fix "else" that doesn't follow close brace '}'.
Link: https://lore.kernel.org/r/1617783353-48249-6-git-send-email-liweihang@huawei.com
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Space is not required after '(', before ')', before ',' and between '*'
and symbol name of a definition.
Link: https://lore.kernel.org/r/1617783353-48249-5-git-send-email-liweihang@huawei.com
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
On RoCE systems, a CM REQ contains a Primary Hop Limit > 1 and Primary
Subnet Local is zero.
In cm_req_handler(), the cm_process_routed_req() function is called. Since
the Primary Subnet Local value is zero in the request, and since this is
RoCE (Primary Local LID is permissive), the following statement will be
executed:
IBA_SET(CM_REQ_PRIMARY_SL, req_msg, wc->sl);
This corrupts SL in req_msg if it was different from zero. In other words,
a request to setup a connection using an SL != zero, will not be honored,
and a connection using SL zero will be created instead.
Fixed by not calling cm_process_routed_req() on RoCE systems, the
cm_process_route_req() is only for IB anyhow.
Fixes: 3971c9f6db ("IB/cm: Add interim support for routed paths")
Link: https://lore.kernel.org/r/1616420132-31005-1-git-send-email-haakon.bugge@oracle.com
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Current code uses many different types when dealing with a port of a RDMA
device: u8, unsigned int and u32. Switch to u32 to clean up the logic.
This allows us to make (at least) the core view consistent and use the
same type. Unfortunately not all places can be converted. Many uverbs
functions expect port to be u8 so keep those places in order not to break
UAPIs. HW/Spec defined values must also not be changed.
With the switch to u32 we now can support devices with more than 255
ports. U32_MAX is reserved to make control logic a bit easier to deal
with. As a device with U32_MAX ports probably isn't going to happen any
time soon this seems like a non issue.
When a device with more than 255 ports is created uverbs will report the
RDMA device as having 255 ports as this is the max currently supported.
The verbs interface is not changed yet because the IBTA spec limits the
port size in too many places to be u8 and all applications that relies in
verbs won't be able to cope with this change. At this stage, we are
extending the interfaces that are using vendor channel solely
Once the limitation is lifted mlx5 in switchdev mode will be able to have
thousands of SFs created by the device. As the only instance of an RDMA
device that reports more than 255 ports will be a representor device and
it exposes itself as a RAW Ethernet only device CM/MAD/IPoIB and other
ULPs aren't effected by this change and their sysfs/interfaces that are
exposes to userspace can remain unchanged.
While here cleanup some alignment issues and remove unneeded sanity
checks (mainly in rdmavt),
Link: https://lore.kernel.org/r/20210301070420.439400-1-leon@kernel.org
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
ib_send_cm_sidr_rep() {
spin_lock_irqsave()
cm_send_sidr_rep_locked() {
...
spin_lock_irq()
....
spin_unlock_irq() <--- this will enable interrupts
}
spin_unlock_irqrestore()
}
spin_unlock_irqrestore() expects interrupts to be disabled but the
internal spin_unlock_irq() will always enable hard interrupts.
Fix this by replacing the internal spin_{lock,unlock}_irq() with
irqsave/restore variants.
It fixes the following kernel trace:
raw_local_irq_restore() called with IRQs enabled
WARNING: CPU: 2 PID: 20001 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x1d/0x20
Call Trace:
_raw_spin_unlock_irqrestore+0x4e/0x50
ib_send_cm_sidr_rep+0x3a/0x50 [ib_cm]
cma_send_sidr_rep+0xa1/0x160 [rdma_cm]
rdma_accept+0x25e/0x350 [rdma_cm]
ucma_accept+0x132/0x1cc [rdma_ucm]
ucma_write+0xbf/0x140 [rdma_ucm]
vfs_write+0xc1/0x340
ksys_write+0xb3/0xe0
do_syscall_64+0x2d/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixes: 87c4c774cb ("RDMA/cm: Protect access to remote_sidr_table")
Link: https://lore.kernel.org/r/20210301081844.445823-1-leon@kernel.org
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
When RDMA device has 255 ports, loop iterator i overflows. Due to which
cm_add_one() port iterator loops infinitely. Use core provided port
iterator to avoid the infinite loop.
Fixes: a977049dac ("[PATCH] IB: Add the kernel CM implementation")
Link: https://lore.kernel.org/r/20210127150010.1876121-9-leon@kernel.org
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
A smaller set of patches, nothing stands out as being particularly major
this cycle:
- Driver bug fixes and updates: bnxt_re, cxgb4, rxe, hns, i40iw, cxgb4,
mlx4 and mlx5
- Bug fixes and polishing for the new rts ULP
- Cleanup of uverbs checking for allowed driver operations
- Use sysfs_emit all over the place
- Lots of bug fixes and clarity improvements for hns
- hip09 support for hns
- NDR and 50/100Gb signaling rates
- Remove dma_virt_ops and go back to using the IB DMA wrappers
- mlx5 optimizations for contiguous DMA regions
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull rdma updates from Jason Gunthorpe:
"A smaller set of patches, nothing stands out as being particularly
major this cycle. The biggest item would be the new HIP09 HW support
from HNS, otherwise it was pretty quiet for new work here:
- Driver bug fixes and updates: bnxt_re, cxgb4, rxe, hns, i40iw,
cxgb4, mlx4 and mlx5
- Bug fixes and polishing for the new rts ULP
- Cleanup of uverbs checking for allowed driver operations
- Use sysfs_emit all over the place
- Lots of bug fixes and clarity improvements for hns
- hip09 support for hns
- NDR and 50/100Gb signaling rates
- Remove dma_virt_ops and go back to using the IB DMA wrappers
- mlx5 optimizations for contiguous DMA regions"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (147 commits)
RDMA/cma: Don't overwrite sgid_attr after device is released
RDMA/mlx5: Fix MR cache memory leak
RDMA/rxe: Use acquire/release for memory ordering
RDMA/hns: Simplify AEQE process for different types of queue
RDMA/hns: Fix inaccurate prints
RDMA/hns: Fix incorrect symbol types
RDMA/hns: Clear redundant variable initialization
RDMA/hns: Fix coding style issues
RDMA/hns: Remove unnecessary access right set during INIT2INIT
RDMA/hns: WARN_ON if get a reserved sl from users
RDMA/hns: Avoid filling sl in high 3 bits of vlan_id
RDMA/hns: Do shift on traffic class when using RoCEv2
RDMA/hns: Normalization the judgment of some features
RDMA/hns: Limit the length of data copied between kernel and userspace
RDMA/mlx4: Remove bogus dev_base_lock usage
RDMA/uverbs: Fix incorrect variable type
RDMA/core: Do not indicate device ready when device enablement fails
RDMA/core: Clean up cq pool mechanism
RDMA/core: Update kernel documentation for ib_create_named_qp()
MAINTAINERS: SOFT-ROCE: Change Zhu Yanjun's email address
...
The xarray is never mutated from an IRQ handler, only from work queues
under a spinlock_irq. Thus there is no reason for it be an IRQ type
xarray.
This was copied over from the original IDR code, but the recent rework put
the xarray inside another spinlock_irq which will unbalance the unlocking.
Fixes: c206f8bad1 ("RDMA/cm: Make it clearer how concurrency works in cm_req_handler()")
Link: https://lore.kernel.org/r/0-v1-808b6da3bd3f+1857-cm_xarray_no_irq_jgg@nvidia.com
Reported-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
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Merge tag 'v5.9-rc3' into rdma.git for-next
Required due to dependencies in following patches.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
In the interest of converging on a common instrumentation infrastructure,
modernize the pr_debug() call sites added by commit 119bf81793 ("IB/cm:
Add debug prints to ib_cm"). The new tracepoints appear in a new "ib_cma"
subsystem.
The conversion is somewhat mechanical. Someone more familiar with the
semantics of the recorded information might suggest additional data
capture.
Some benefits include:
- Tracepoints enable "always on" reporting of these errors
- The error records are structured and compact
- Tracepoints provide hooks for eBPF scripts
Sample output:
nfsd-1954 [003] 62.017901: icm_dreq_skipped: local_id=1998890974 remote_id=1129750393 state=DREQ_RCVD lap_state=LAP_UNINIT
Link: https://lore.kernel.org/r/159767239665.2968.10613294222688696646.stgit@klimt.1015granger.net
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Fix the following sparse error by adding annotation to
cm_queue_work_unlock() that it releases cm_id_priv->lock lock.
drivers/infiniband/core/cm.c:936:24: warning: context imbalance in
'cm_queue_work_unlock' - unexpected unlock
Fixes: e83f195aa4 ("RDMA/cm: Pull duplicated code into cm_queue_work_unlock()")
Link: https://lore.kernel.org/r/20200611130045.1994026-1-leon@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
If the cm_id state is IB_CM_REP_SENT when cm_destroy_id() is called, it
calls cm_send_rej_locked().
In cm_send_rej_locked(), it calls cm_enter_timewait() and the state is
changed to IB_CM_TIMEWAIT.
Now back to cm_destroy_id(), it breaks from the switch statement, and the
next call is WARN_ON(cm_id->state != IB_CM_IDLE).
This triggers a spurious warning. Instead, the code should goto retest
after returning from cm_send_rej_locked() to move the state to IDLE.
Fixes: 67b3c8dcea ("RDMA/cm: Make sure the cm_id is in the IB_CM_IDLE state in destroy")
Link: https://lore.kernel.org/r/1591191218-9446-1-git-send-email-ka-cheong.poon@oracle.com
Signed-off-by: Ka-Cheong Poon <ka-cheong.poon@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
ECE parameters are exchanged through REQ->REP/SIDR_REP messages, this
patch adds the data to provide to other side of CMID communication
channel.
Link: https://lore.kernel.org/r/20200526103304.196371-5-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
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Merge tag 'v5.7-rc6' into rdma.git for-next
Linux 5.7-rc6
Conflict in drivers/net/ethernet/mellanox/mlx5/core/steering/dr_send.c
resolved by deleting dr_cq_event, matching how netdev resolved it.
Required for dependencies in the following patches.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
All callers need the 'get', so do it in a central place before returning
the pointer.
Link: https://lore.kernel.org/r/20200506074701.9775-11-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The only caller doesn't care about the timewait, so acquire and return the
cm_id_private from the function.
Link: https://lore.kernel.org/r/20200506074701.9775-8-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The way the cm_timewait_info is converted into a work and then freed
is very subtle and surprising, add a note clarifying the lifetime
here.
Link: https://lore.kernel.org/r/20200506074701.9775-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Also rename it to cm_remove_remote(). This function now removes the
tracking of the remote ID/QPN in the redblack trees from a cm_id_private.
Replace a open-coded version with a call. The open coded version was
deleting only the remote_id, however at this call site the qpn can not
have been in the RB tree either, so the cm_remove_remote() will do the
same.
Link: https://lore.kernel.org/r/20200506074701.9775-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
While unlocking a spinlock held by the caller is a disturbing pattern,
this extensively duplicated code is even worse. Pull all the duplicates
into a function and explain the purpose of the algorithm.
The on creation side call in cm_req_handler() which is different has been
micro-optimized on the basis that the work_count == -1 during creation,
remove that and just use the normal function.
Link: https://lore.kernel.org/r/20200506074701.9775-5-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The 'goto out' label doesn't read ret, so don't set it.
Link: https://lore.kernel.org/r/20200506074701.9775-4-leon@kernel.org
Signed-off-by: Danit Goldberg <danitg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This cannot happen, all callers pass in one of the two pointers. Use
a WARN_ON guard instead.
Link: https://lore.kernel.org/r/20200506074701.9775-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
When a client is added it isn't allowed to fail, but all the client's have
various failure paths within their add routines.
This creates the very fringe condition where the client was added, failed
during add and didn't set the client_data. The core code will then still
call other client_data centric ops like remove(), rename(), get_nl_info(),
and get_net_dev_by_params() with NULL client_data - which is confusing and
unexpected.
If the add() callback fails, then do not call any more client ops for the
device, even remove.
Remove all the now redundant checks for NULL client_data in ops callbacks.
Update all the add() callbacks to return error codes
appropriately. EOPNOTSUPP is used for cases where the ULP does not support
the ib_device - eg because it only works with IB.
Link: https://lore.kernel.org/r/20200421172440.387069-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The xa_alloc_cyclic_irq() function returns either 0 or 1 on success and
negatives on error. This code treats 1 as an error and returns ERR_PTR(1)
which will cause an Oops in the caller.
Fixes: ae78ff3a0f ("RDMA/cm: Convert local_id_table to XArray")
Link: https://lore.kernel.org/r/20200407093714.GA80285@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The cm_reset_to_idle() call before formatting event changed the CM_ID
state from IB_CM_REQ_RCVD to be IB_CM_IDLE. It caused to wrong value of
CM_REJ_MESSAGE_REJECTED field.
The result of that was that rdma_reject() calls in the passive side didn't
generate RDMA_CM_EVENT_REJECTED event in the active side.
Fixes: 81ddb41f87 ("RDMA/cm: Allow ib_send_cm_rej() to be done under lock")
Link: https://lore.kernel.org/r/20200406173242.1465911-1-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The first switch statement in cm_destroy_id() tries to move the ID to
either IB_CM_IDLE or IB_CM_TIMEWAIT. Both states will block concurrent
MAD handlers from progressing.
Previous patches removed the unreliably lock/unlock sequences in this
flow, this patch removes the extra locking steps and adds the missing
parts to guarantee that destroy reaches IB_CM_IDLE. There is no point in
leaving the ID in the IB_CM_TIMEWAIT state the memory about to be kfreed.
Rework things to hold the lock across all the state transitions and
directly assert when done that it ended up in IB_CM_IDLE as expected.
This was accompanied by a careful audit of all the state transitions here,
which generally did end up in IDLE on their success and non-racy paths.
Link: https://lore.kernel.org/r/20200310092545.251365-16-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The first thing ib_send_cm_sidr_rep() does is obtain the lock, so use the
usual unlocked wrapper, locked actor pattern here.
Get rid of the cm_reject_sidr_req() wrapper so each call site can call the
locked or unlocked version as required.
This avoids a sketchy lock/unlock sequence (which could allow state to
change) during cm_destroy_id().
Link: https://lore.kernel.org/r/20200310092545.251365-15-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The first thing ib_send_cm_rej() does is obtain the lock, so use the usual
unlocked wrapper, locked actor pattern here.
This avoids a sketchy lock/unlock sequence (which could allow state to
change) during cm_destroy_id().
While here simplify some of the logic in the implementation.
Link: https://lore.kernel.org/r/20200310092545.251365-14-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The first thing ib_send_cm_drep() does is obtain the lock, so use the
usual unlocked wrapper, locked actor pattern here.
This avoids a sketchy lock/unlock sequence (which could allow state to
change) during cm_destroy_id().
Link: https://lore.kernel.org/r/20200310092545.251365-13-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The first thing ib_send_cm_dreq() does is obtain the lock, so use the
usual unlocked wrapper, locked actor pattern here.
This avoids a sketchy lock/unlock sequence (which could allow state to
change) during cm_destroy_id().
Link: https://lore.kernel.org/r/20200310092545.251365-12-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
These functions all touch state, so must be called under the lock.
Inspection shows this is currently true.
Link: https://lore.kernel.org/r/20200310092545.251365-11-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
ib_crate_cm_id() immediately places the id in the xarray, and publishes it
into the remote_id and remote_qpn rbtrees. This makes it visible to other
threads before it is fully set up.
It appears the thinking here was that the states IB_CM_IDLE and
IB_CM_REQ_RCVD do not allow any MAD handler or lookup in the remote_id and
remote_qpn rbtrees to advance.
However, cm_rej_handler() does take an action on IB_CM_REQ_RCVD, which is
not really expected by the design.
Make the whole thing clearer:
- Keep the new cm_id out of the xarray until it is completely set up.
This directly prevents MAD handlers and all rbtree lookups from seeing
the pointer.
- Move all the trivial setup right to the top so it is obviously done
before any concurrency begins
- Move the mutation of the cm_id_priv out of cm_match_id() and into the
caller so the state transition is obvious
- Place the manipulation of the work_list at the end, under lock, after
the cm_id is placed in the xarray. The work_count cannot change on an
ID outside the xarray.
- Add some comments
Link: https://lore.kernel.org/r/20200310092545.251365-9-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
ib_create_cm_id() immediately places the id in the xarray, so it is visible
to network traffic.
The state is initially set to IB_CM_IDLE and all the MAD handlers will
test this state under lock and refuse to advance from IDLE, so adding to
the xarray is harmless.
Further, the set to IB_CM_SIDR_REQ_RCVD also excludes all MAD handlers.
However, the local_id isn't even used for SIDR mode, and there will be no
input MADs related to the newly created ID.
So, make the whole flow simpler so it can be understood:
- Do not put the SIDR cm_id in the xarray. This directly shows that there
is no concurrency
- Delete the confusing work_count and pending_list manipulations. This
mechanism is only used by MAD handlers and timewait, neither of which
apply to SIDR.
- Add a few comments and rename 'cur_cm_id_priv' to 'listen_cm_id_priv'
- Move other loose sets up to immediately after cm_id creation so that
the cm_id is fully configured right away. This fixes an oversight where
the service_id will not be returned back on a IB_SIDR_UNSUPPORTED
reject.
Link: https://lore.kernel.org/r/20200310092545.251365-8-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The lock should not be dropped before doing the pr_debug() print as it is
accessing data protected by the lock, such as id.state.
Fixes: 119bf81793 ("IB/cm: Add debug prints to ib_cm")
Link: https://lore.kernel.org/r/20200310092545.251365-7-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Any manipulation of cm_id->state must be done under the cm_id_priv->lock,
the two routines that added listens did not follow this rule, because they
never participate in any concurrent access around the state.
However, since this exception makes the code hard to understand, simplify
the flow so that it can be fully locked:
- Move manipulation of listen_sharecount into cm_insert_listen() so it is
trivially under the cm.lock without having to expose the cm.lock to the
caller.
- Push the cm.lock down into cm_insert_listen() and have the function
increment the reference count before returning an existing pointer.
- Split ib_cm_listen() into an cm_init_listen() and do not call
ib_cm_listen() from ib_cm_insert_listen()
- Make both ib_cm_listen() and ib_cm_insert_listen() directly call
cm_insert_listen() under their cm_id_priv->lock which does both a
collision detect and, if needed, the insert (atomically)
- Enclose all state manipulation within the cm_id_priv->lock, notice this
set can be done safely after cm_insert_listen() as no reader is allowed
to read the state without holding the lock.
- Do not set the listen cm_id in the xarray, as it is never correct to
look it up. This makes the concurrency simpler to understand.
Many needless error unwinds are removed in the process.
Link: https://lore.kernel.org/r/20200310092545.251365-6-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Too much of the destruction is very carefully sensitive to the state
and various other things. Move more code to the unconditional path and
add several WARN_ONs to check consistency.
Link: https://lore.kernel.org/r/20200310092545.251365-5-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
When creating a cm_id during REQ the id immediately becomes visible to the
other MAD handlers, and shortly after the state is moved to IB_CM_REQ_RCVD
This allows cm_rej_handler() to run concurrently and free the work:
CPU 0 CPU1
cm_req_handler()
ib_create_cm_id()
cm_match_req()
id_priv->state = IB_CM_REQ_RCVD
cm_rej_handler()
cm_acquire_id()
spin_lock(&id_priv->lock)
switch (id_priv->state)
case IB_CM_REQ_RCVD:
cm_reset_to_idle()
kfree(id_priv->timewait_info);
goto destroy
destroy:
kfree(id_priv->timewait_info);
id_priv->timewait_info = NULL
Causing a double free or worse.
Do not free the timewait_info without also holding the
id_priv->lock. Simplify this entire flow by making the free unconditional
during cm_destroy_id() and removing the confusing special case error
unwind during creation of the timewait_info.
This also fixes a leak of the timewait if cm_destroy_id() is called in
IB_CM_ESTABLISHED with an XRC TGT QP. The state machine will be left in
ESTABLISHED while it needed to transition through IB_CM_TIMEWAIT to
release the timewait pointer.
Also fix a leak of the timewait_info if the caller mis-uses the API and
does ib_send_cm_reqs().
Fixes: a977049dac ("[PATCH] IB: Add the kernel CM implementation")
Link: https://lore.kernel.org/r/20200310092545.251365-4-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The test here typod the cm_id_priv to use, it used the one that was
freshly allocated. By definition the allocated one has the matching
cm_handler and zero context, so the condition was always true.
Instead check that the existing listening ID is compatible with the
proposed handler so that it can be shared, as was originally intended.
Fixes: 067b171b86 ("IB/cm: Share listening CM IDs")
Link: https://lore.kernel.org/r/20200310092545.251365-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
xa_alloc_cyclic() is a SMP release to be paired with some later acquire
during xa_load() as part of cm_acquire_id().
As such, xa_alloc_cyclic() must be done after the cm_id is fully
initialized, in particular, it absolutely must be after the
refcount_set(), otherwise the refcount_inc() in cm_acquire_id() may not
see the set.
As there are several cases where a reader will be able to use the
id.local_id after cm_acquire_id in the IB_CM_IDLE state there needs to be
an unfortunate split into a NULL allocate and a finalizing xa_store.
Fixes: a977049dac ("[PATCH] IB: Add the kernel CM implementation")
Link: https://lore.kernel.org/r/20200310092545.251365-2-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
