linux.git/net/smc, branch v6.6

net/smc: return the right falback reason when prefix checks fail

2023-10-16T23:37:40+00:00

In the smc_listen_work(), if smc_listen_prfx_check() failed,
the real reason: SMC_CLC_DECL_DIFFPREFIX was dropped, and
SMC_CLC_DECL_NOSMCDEV was returned.

Althrough this is also kind of SMC_CLC_DECL_NOSMCDEV, but return
the real reason is much friendly for debugging.

Fixes: e49300a6bf62 ("net/smc: add listen processing for SMC-Rv2")
Signed-off-by: Dust Li 
Reviewed-by: Alexandra Winter 
Reviewed-by: Wenjia Zhang 
Link: https://lore.kernel.org/r/20231012123729.29307-1-dust.li@linux.alibaba.com
Signed-off-by: Jakub Kicinski

net/smc: fix smc clc failed issue when netdevice not in init_net

2023-10-13T23:52:02+00:00

If the netdevice is within a container and communicates externally
through network technologies such as VxLAN, we won't be able to find
routing information in the init_net namespace. To address this issue,
we need to add a struct net parameter to the smc_ib_find_route function.
This allow us to locate the routing information within the corresponding
net namespace, ensuring the correct completion of the SMC CLC interaction.

Fixes: e5c4744cfb59 ("net/smc: add SMC-Rv2 connection establishment")
Signed-off-by: Albert Huang 
Reviewed-by: Dust Li 
Reviewed-by: Wenjia Zhang 
Link: https://lore.kernel.org/r/20231011074851.95280-1-huangjie.albert@bytedance.com
Signed-off-by: Jakub Kicinski

net/smc: Fix pos miscalculation in statistics

2023-10-11T09:36:35+00:00

SMC_STAT_PAYLOAD_SUB(_smc_stats, _tech, key, _len, _rc) will calculate
wrong bucket positions for payloads of exactly 4096 bytes and
(1 << (m + 12)) bytes, with m == SMC_BUF_MAX - 1.

Intended bucket distribution:
Assume l == size of payload, m == SMC_BUF_MAX - 1.

Bucket 0                : 0 < l <= 2^13
Bucket n, 1 <= n <= m-1 : 2^(n+12) < l <= 2^(n+13)
Bucket m                : l > 2^(m+12)

Current solution:
_pos = fls64((l) >> 13)
[...]
_pos = (_pos < m) ? ((l == 1 << (_pos + 12)) ? _pos - 1 : _pos) : m

For l == 4096, _pos == -1, but should be _pos == 0.
For l == (1 << (m + 12)), _pos == m, but should be _pos == m - 1.

In order to avoid special treatment of these corner cases, the
calculation is adjusted. The new solution first subtracts the length by
one, and then calculates the correct bucket by shifting accordingly,
i.e. _pos = fls64((l - 1) >> 13), l > 0.
This not only fixes the issues named above, but also makes the whole
bucket assignment easier to follow.

Same is done for SMC_STAT_RMB_SIZE_SUB(_smc_stats, _tech, k, _len),
where the calculation of the bucket position is similar to the one
named above.

Fixes: e0e4b8fa5338 ("net/smc: Add SMC statistics support")
Suggested-by: Halil Pasic 
Signed-off-by: Nils Hoppmann 
Reviewed-by: Halil Pasic 
Reviewed-by: Wenjia Zhang 
Reviewed-by: Dust Li 
Signed-off-by: David S. Miller

net/smc: Fix dependency of SMC on ISM

2023-10-10T09:51:41+00:00

When the SMC protocol is built into the kernel proper while ISM is
configured to be built as module, linking the kernel fails due to
unresolved dependencies out of net/smc/smc_ism.o to
ism_get_smcd_ops, ism_register_client, and ism_unregister_client
as reported via the linux-next test automation (see link).
This however is a bug introduced a while ago.

Correct the dependency list in ISM's and SMC's Kconfig to reflect the
dependencies that are actually inverted. With this you cannot build a
kernel with CONFIG_SMC=y and CONFIG_ISM=m. Either ISM needs to be 'y',
too - or a 'n'. That way, SMC can still be configured on non-s390
architectures that do not have (nor need) an ISM driver.

Fixes: 89e7d2ba61b7 ("net/ism: Add new API for client registration")
Reported-by: Randy Dunlap 
Closes: https://lore.kernel.org/linux-next/d53b5b50-d894-4df8-8969-fd39e63440ae@infradead.org/
Co-developed-by: Wenjia Zhang 
Signed-off-by: Wenjia Zhang 
Signed-off-by: Gerd Bayer 
Reviewed-by: Simon Horman 
Tested-by: Simon Horman  # build-tested
Acked-by: Randy Dunlap 
Tested-by: Randy Dunlap  # build-tested
Link: https://lore.kernel.org/r/20231006125847.1517840-1-gbayer@linux.ibm.com
Signed-off-by: Paolo Abeni

net/smc: use smc_lgr_list.lock to protect smc_lgr_list.list iterate in smcr_port_add

2023-09-10T18:31:42+00:00

While doing smcr_port_add, there maybe linkgroup add into or delete
from smc_lgr_list.list at the same time, which may result kernel crash.
So, use smc_lgr_list.lock to protect smc_lgr_list.list iterate in
smcr_port_add.

The crash calltrace show below:
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 0 PID: 559726 Comm: kworker/0:92 Kdump: loaded Tainted: G
Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 449e491 04/01/2014
Workqueue: events smc_ib_port_event_work [smc]
RIP: 0010:smcr_port_add+0xa6/0xf0 [smc]
RSP: 0000:ffffa5a2c8f67de0 EFLAGS: 00010297
RAX: 0000000000000001 RBX: ffff9935e0650000 RCX: 0000000000000000
RDX: 0000000000000010 RSI: ffff9935e0654290 RDI: ffff9935c8560000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffff9934c0401918
R10: 0000000000000000 R11: ffffffffb4a5c278 R12: ffff99364029aae4
R13: ffff99364029aa00 R14: 00000000ffffffed R15: ffff99364029ab08
FS:  0000000000000000(0000) GS:ffff994380600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000f06a10003 CR4: 0000000002770ef0
PKRU: 55555554
Call Trace:
 smc_ib_port_event_work+0x18f/0x380 [smc]
 process_one_work+0x19b/0x340
 worker_thread+0x30/0x370
 ? process_one_work+0x340/0x340
 kthread+0x114/0x130
 ? __kthread_cancel_work+0x50/0x50
 ret_from_fork+0x1f/0x30

Fixes: 1f90a05d9ff9 ("net/smc: add smcr_port_add() and smcr_link_up() processing")
Signed-off-by: Guangguan Wang 
Signed-off-by: David S. Miller

net/smc: bugfix for smcr v2 server connect success statistic

2023-09-10T18:31:42+00:00

In the macro SMC_STAT_SERV_SUCC_INC, the smcd_version is used
to determin whether to increase the v1 statistic or the v2
statistic. It is correct for SMCD. But for SMCR, smcr_version
should be used.

Signed-off-by: Guangguan Wang 
Signed-off-by: David S. Miller

Merge tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

2023-08-30T00:39:15+00:00

Pull sysctl updates from Luis Chamberlain:
 "Long ago we set out to remove the kitchen sink on kernel/sysctl.c
  arrays and placings sysctls to their own sybsystem or file to help
  avoid merge conflicts. Matthew Wilcox pointed out though that if we're
  going to do that we might as well also *save* space while at it and
  try to remove the extra last sysctl entry added at the end of each
  array, a sentintel, instead of bloating the kernel by adding a new
  sentinel with each array moved.

  Doing that was not so trivial, and has required slowing down the moves
  of kernel/sysctl.c arrays and measuring the impact on size by each new
  move.

  The complex part of the effort to help reduce the size of each sysctl
  is being done by the patient work of el señor Don Joel Granados. A lot
  of this is truly painful code refactoring and testing and then trying
  to measure the savings of each move and removing the sentinels.
  Although Joel already has code which does most of this work,
  experience with sysctl moves in the past shows is we need to be
  careful due to the slew of odd build failures that are possible due to
  the amount of random Kconfig options sysctls use.

  To that end Joel's work is split by first addressing the major
  housekeeping needed to remove the sentinels, which is part of this
  merge request. The rest of the work to actually remove the sentinels
  will be done later in future kernel releases.

  The preliminary math is showing this will all help reduce the overall
  build time size of the kernel and run time memory consumed by the
  kernel by about ~64 bytes per array where we are able to remove each
  sentinel in the future. That also means there is no more bloating the
  kernel with the extra ~64 bytes per array moved as no new sentinels
  are created"

* tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  sysctl: Use ctl_table_size as stopping criteria for list macro
  sysctl: SIZE_MAX->ARRAY_SIZE in register_net_sysctl
  vrf: Update to register_net_sysctl_sz
  networking: Update to register_net_sysctl_sz
  netfilter: Update to register_net_sysctl_sz
  ax.25: Update to register_net_sysctl_sz
  sysctl: Add size to register_net_sysctl function
  sysctl: Add size arg to __register_sysctl_init
  sysctl: Add size to register_sysctl
  sysctl: Add a size arg to __register_sysctl_table
  sysctl: Add size argument to init_header
  sysctl: Add ctl_table_size to ctl_table_header
  sysctl: Use ctl_table_header in list_for_each_table_entry
  sysctl: Prefer ctl_table_header in proc_sysctl

net: annotate data-races around sk->sk_lingertime

2023-08-21T06:41:57+00:00

sk_getsockopt() runs locklessly. This means sk->sk_lingertime
can be read while other threads are changing its value.

Other reads also happen without socket lock being held,
and must be annotated.

Remove preprocessor logic using BITS_PER_LONG, compilers
are smart enough to figure this by themselves.

v2: fixed a clang W=1 (-Wtautological-constant-out-of-range-compare) warning
    (Jakub)

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net/smc: Extend SMCR v2 linkgroup netlink attribute

2023-08-19T11:46:53+00:00

Add SMC_NLA_LGR_R_V2_MAX_CONNS and SMC_NLA_LGR_R_V2_MAX_LINKS
to SMCR v2 linkgroup netlink attribute SMC_NLA_LGR_R_V2 for
linkgroup's detail info showing.

Signed-off-by: Guangguan Wang 
Reviewed-by: Jan Karcher 
Signed-off-by: David S. Miller

net/smc: support max links per lgr negotiation in clc handshake

2023-08-19T11:46:53+00:00

Support max links per lgr negotiation in clc handshake for SMCR v2.1,
which is one of smc v2.1 features. Server makes decision for the final
value of max links based on the client preferred max links and
self-preferred max links. Here use the minimum value of the client
preferred max links and server preferred max links.

Client                                       Server
     Proposal(max links(client preferred))
     -------------------------------------->

     Accept(max links(accepted value))
accepted value=min(client preferred, server preferred)
     <-------------------------------------

      Confirm(max links(accepted value))
     ------------------------------------->

Signed-off-by: Guangguan Wang 
Reviewed-by: Tony Lu 
Reviewed-by: Jan Karcher 
Signed-off-by: David S. Miller