linux-toradex.git/lib/rhashtable.c, branch v5.1-rc4

rhashtable: Still do rehash when we get EEXIST

2019-03-21T20:57:28+00:00

As it stands if a shrink is delayed because of an outstanding
rehash, we will go into a rescheduling loop without ever doing
the rehash.

This patch fixes this by still carrying out the rehash and then
rescheduling so that we can shrink after the completion of the
rehash should it still be necessary.

The return value of EEXIST captures this case and other cases
(e.g., another thread expanded/rehashed the table at the same
time) where we should still proceed with the rehash.

Fixes: da20420f83ea ("rhashtable: Add nested tables")
Reported-by: Josh Elsasser 
Signed-off-by: Herbert Xu 
Tested-by: Josh Elsasser 
Signed-off-by: David S. Miller

rhashtable: Remove obsolete rhashtable_walk_init function

2019-02-22T12:49:00+00:00

The rhashtable_walk_init function has been obsolete for more than
two years.  This patch finally converts its last users over to
rhashtable_walk_enter and removes it.

Signed-off-by: Herbert Xu 
Signed-off-by: Johannes Berg

rhashtable: detect when object movement between tables might have invalidated a lookup

2018-12-03T23:31:55+00:00

Some users of rhashtables might need to move an object from one table
to another -  this appears to be the reason for the incomplete usage
of NULLS markers.

To support these, we store a unique NULLS_MARKER at the end of
each chain, and when a search fails to find a match, we check
if the NULLS marker found was the expected one.  If not, the search
may not have examined all objects in the target bucket, so it is
repeated.

The unique NULLS_MARKER is derived from the address of the
head of the chain.  As this cannot be derived at load-time the
static rhnull in rht_bucket_nested() needs to be initialised
at run time.

Any caller of a lookup function must still be prepared for the
possibility that the object returned is in a different table - it
might have been there for some time.

Note that this does NOT provide support for other uses of
NULLS_MARKERs such as allocating with SLAB_TYPESAFE_BY_RCU or changing
the key of an object and re-inserting it in the same table.
These could only be done safely if new objects were inserted
at the *start* of a hash chain, and that is not currently the case.

Signed-off-by: NeilBrown 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2018-08-27T18:59:39+00:00

Pull networking fixes from David Miller:

 1) ICE, E1000, IGB, IXGBE, and I40E bug fixes from the Intel folks.

 2) Better fix for AB-BA deadlock in packet scheduler code, from Cong
    Wang.

 3) bpf sockmap fixes (zero sized key handling, etc.) from Daniel
    Borkmann.

 4) Send zero IPID in TCP resets and SYN-RECV state ACKs, to prevent
    attackers using it as a side-channel. From Eric Dumazet.

 5) Memory leak in mediatek bluetooth driver, from Gustavo A. R. Silva.

 6) Hook up rt->dst.input of ipv6 anycast routes properly, from Hangbin
    Liu.

 7) hns and hns3 bug fixes from Huazhong Tan.

 8) Fix RIF leak in mlxsw driver, from Ido Schimmel.

 9) iova range check fix in vhost, from Jason Wang.

10) Fix hang in do_tcp_sendpages() with tls, from John Fastabend.

11) More r8152 chips need to disable RX aggregation, from Kai-Heng Feng.

12) Memory exposure in TCA_U32_SEL handling, from Kees Cook.

13) TCP BBR congestion control fixes from Kevin Yang.

14) hv_netvsc, ignore non-PCI devices, from Stephen Hemminger.

15) qed driver fixes from Tomer Tayar.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits)
  net: sched: Fix memory exposure from short TCA_U32_SEL
  qed: fix spelling mistake "comparsion" -> "comparison"
  vhost: correctly check the iova range when waking virtqueue
  qlge: Fix netdev features configuration.
  net: macb: do not disable MDIO bus at open/close time
  Revert "net: stmmac: fix build failure due to missing COMMON_CLK dependency"
  net: macb: Fix regression breaking non-MDIO fixed-link PHYs
  mlxsw: spectrum_switchdev: Do not leak RIFs when removing bridge
  i40e: fix condition of WARN_ONCE for stat strings
  i40e: Fix for Tx timeouts when interface is brought up if DCB is enabled
  ixgbe: fix driver behaviour after issuing VFLR
  ixgbe: Prevent unsupported configurations with XDP
  ixgbe: Replace GFP_ATOMIC with GFP_KERNEL
  igb: Replace mdelay() with msleep() in igb_integrated_phy_loopback()
  igb: Replace GFP_ATOMIC with GFP_KERNEL in igb_sw_init()
  igb: Use an advanced ctx descriptor for launchtime
  e1000: ensure to free old tx/rx rings in set_ringparam()
  e1000: check on netif_running() before calling e1000_up()
  ixgb: use dma_zalloc_coherent instead of allocator/memset
  ice: Trivial formatting fixes
  ...

lib/rhashtable: guarantee initial hashtable allocation

2018-08-22T17:52:52+00:00

rhashtable_init() may fail due to -ENOMEM, thus making the entire api
unusable.  This patch removes this scenario, however unlikely.  In order
to guarantee memory allocation, this patch always ends up doing
GFP_KERNEL|__GFP_NOFAIL for both the tbl as well as
alloc_bucket_spinlocks().

Upon the first table allocation failure, we shrink the size to the
smallest value that makes sense and retry with __GFP_NOFAIL semantics.
With the defaults, this means that from 64 buckets, we retry with only 4.
Any later issues regarding performance due to collisions or larger table
resizing (when more memory becomes available) is the least of our
problems.

Link: http://lkml.kernel.org/r/20180712185241.4017-9-manfred@colorfullife.com
Signed-off-by: Davidlohr Bueso 
Signed-off-by: Manfred Spraul 
Acked-by: Herbert Xu 
Cc: Dmitry Vyukov 
Cc: Kees Cook 
Cc: Michael Kerrisk 
Cc: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/rhashtable: simplify bucket_table_alloc()

2018-08-22T17:52:52+00:00

As of ce91f6ee5b3b ("mm: kvmalloc does not fallback to vmalloc for
incompatible gfp flags") we can simplify the caller and trust kvzalloc()
to just do the right thing.  For the case of the GFP_ATOMIC context, we
can drop the __GFP_NORETRY flag for obvious reasons, and for the
__GFP_NOWARN case, however, it is changed such that the caller passes the
flag instead of making bucket_table_alloc() handle it.

This slightly changes the gfp flags passed on to nested_table_alloc() as
it will now also use GFP_ATOMIC | __GFP_NOWARN.  However, I consider this
a positive consequence as for the same reasons we want nowarn semantics in
bucket_table_alloc().

[manfred@colorfullife.com: commit id extended to 12 digits, line wraps updated]
Link: http://lkml.kernel.org/r/20180712185241.4017-8-manfred@colorfullife.com
Signed-off-by: Davidlohr Bueso 
Signed-off-by: Manfred Spraul 
Acked-by: Michal Hocko 
Cc: Dmitry Vyukov 
Cc: Herbert Xu 
Cc: Kees Cook 
Cc: Michael Kerrisk 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rhashtable: remove duplicated include from rhashtable.c

2018-08-21T02:18:50+00:00

Remove duplicated include.

Signed-off-by: Yue Haibing 
Signed-off-by: David S. Miller

Merge ra.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux

2018-07-21T04:17:12+00:00

All conflicts were trivial overlapping changes, so reasonably
easy to resolve.

Signed-off-by: David S. Miller

lib/rhashtable: consider param->min_size when setting initial table size

2018-07-18T20:27:43+00:00

rhashtable_init() currently does not take into account the user-passed
min_size parameter unless param->nelem_hint is set as well. As such,
the default size (number of buckets) will always be HASH_DEFAULT_SIZE
even if the smallest allowed size is larger than that. Remediate this
by unconditionally calling into rounded_hashtable_size() and handling
things accordingly.

Signed-off-by: Davidlohr Bueso 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller

rhashtable: add restart routine in rhashtable_free_and_destroy()

2018-07-09T23:28:51+00:00

rhashtable_free_and_destroy() cancels re-hash deferred work
then walks and destroys elements. at this moment, some elements can be
still in future_tbl. that elements are not destroyed.

test case:
nft_rhash_destroy() calls rhashtable_free_and_destroy() to destroy
all elements of sets before destroying sets and chains.
But rhashtable_free_and_destroy() doesn't destroy elements of future_tbl.
so that splat occurred.

test script:
   %cat test.nft
   table ip aa {
	   map map1 {
		   type ipv4_addr : verdict;
		   elements = {
			   0 : jump a0,
			   1 : jump a0,
			   2 : jump a0,
			   3 : jump a0,
			   4 : jump a0,
			   5 : jump a0,
			   6 : jump a0,
			   7 : jump a0,
			   8 : jump a0,
			   9 : jump a0,
		}
	   }
	   chain a0 {
	   }
   }
   flush ruleset
   table ip aa {
	   map map1 {
		   type ipv4_addr : verdict;
		   elements = {
			   0 : jump a0,
			   1 : jump a0,
			   2 : jump a0,
			   3 : jump a0,
			   4 : jump a0,
			   5 : jump a0,
			   6 : jump a0,
			   7 : jump a0,
			   8 : jump a0,
			   9 : jump a0,
		   }
	   }
	   chain a0 {
	   }
   }
   flush ruleset

   %while :; do nft -f test.nft; done

Splat looks like:
[  200.795603] kernel BUG at net/netfilter/nf_tables_api.c:1363!
[  200.806944] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[  200.812253] CPU: 1 PID: 1582 Comm: nft Not tainted 4.17.0+ #24
[  200.820297] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015
[  200.830309] RIP: 0010:nf_tables_chain_destroy.isra.34+0x62/0x240 [nf_tables]
[  200.838317] Code: 43 50 85 c0 74 26 48 8b 45 00 48 8b 4d 08 ba 54 05 00 00 48 c7 c6 60 6d 29 c0 48 c7 c7 c0 65 29 c0 4c 8b 40 08 e8 58 e5 fd f8 <0f> 0b 48 89 da 48 b8 00 00 00 00 00 fc ff
[  200.860366] RSP: 0000:ffff880118dbf4d0 EFLAGS: 00010282
[  200.866354] RAX: 0000000000000061 RBX: ffff88010cdeaf08 RCX: 0000000000000000
[  200.874355] RDX: 0000000000000061 RSI: 0000000000000008 RDI: ffffed00231b7e90
[  200.882361] RBP: ffff880118dbf4e8 R08: ffffed002373bcfb R09: ffffed002373bcfa
[  200.890354] R10: 0000000000000000 R11: ffffed002373bcfb R12: dead000000000200
[  200.898356] R13: dead000000000100 R14: ffffffffbb62af38 R15: dffffc0000000000
[  200.906354] FS:  00007fefc31fd700(0000) GS:ffff88011b800000(0000) knlGS:0000000000000000
[  200.915533] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  200.922355] CR2: 0000557f1c8e9128 CR3: 0000000106880000 CR4: 00000000001006e0
[  200.930353] Call Trace:
[  200.932351]  ? nf_tables_commit+0x26f6/0x2c60 [nf_tables]
[  200.939525]  ? nf_tables_setelem_notify.constprop.49+0x1a0/0x1a0 [nf_tables]
[  200.947525]  ? nf_tables_delchain+0x6e0/0x6e0 [nf_tables]
[  200.952383]  ? nft_add_set_elem+0x1700/0x1700 [nf_tables]
[  200.959532]  ? nla_parse+0xab/0x230
[  200.963529]  ? nfnetlink_rcv_batch+0xd06/0x10d0 [nfnetlink]
[  200.968384]  ? nfnetlink_net_init+0x130/0x130 [nfnetlink]
[  200.975525]  ? debug_show_all_locks+0x290/0x290
[  200.980363]  ? debug_show_all_locks+0x290/0x290
[  200.986356]  ? sched_clock_cpu+0x132/0x170
[  200.990352]  ? find_held_lock+0x39/0x1b0
[  200.994355]  ? sched_clock_local+0x10d/0x130
[  200.999531]  ? memset+0x1f/0x40

V2:
 - free all tables requested by Herbert Xu

Signed-off-by: Taehee Yoo 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller