kernel/linux.git/include, branch v4.4.89

tty: improve tty_insert_flip_char() fast path

2017-09-27T09:00:13+00:00

commit 979990c6284814617d8f2179d197f72ff62b5d85 upstream. kernelci.org reports a crazy stack usage for the VT code when CONFIG_KASAN is enabled: drivers/tty/vt/keyboard.c: In function 'kbd_keycode': drivers/tty/vt/keyboard.c:1452:1: error: the frame size of 2240 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] The problem is that tty_insert_flip_char() gets inlined many times into kbd_keycode(), and also into other functions, and each copy requires 128 bytes for stack redzone to check for a possible out-of-bounds access on the 'ch' and 'flags' arguments that are passed into tty_insert_flip_string_flags as a variable-length string. This introduces a new __tty_insert_flip_char() function for the slow path, which receives the two arguments by value. This completely avoids the problem and the stack usage goes back down to around 100 bytes. Without KASAN, this is also slightly better, as we don't have to spill the arguments to the stack but can simply pass 'ch' and 'flag' in registers, saving a few bytes in .text for each call site. This should be backported to linux-4.0 or later, which first introduced the stack sanitizer in the kernel. Fixes: c420f167db8c ("kasan: enable stack instrumentation") Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman

Revert "net: fix percpu memory leaks"

2017-09-27T09:00:11+00:00

[ Upstream commit 5a63643e583b6a9789d7a225ae076fb4e603991c ] This reverts commit 1d6119baf0610f813eb9d9580eb4fd16de5b4ceb. After reverting commit 6d7b857d541e ("net: use lib/percpu_counter API for fragmentation mem accounting") then here is no need for this fix-up patch. As percpu_counter is no longer used, it cannot memory leak it any-longer. Fixes: 6d7b857d541e ("net: use lib/percpu_counter API for fragmentation mem accounting") Fixes: 1d6119baf061 ("net: fix percpu memory leaks") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Revert "net: use lib/percpu_counter API for fragmentation mem accounting"

2017-09-27T09:00:11+00:00

[ Upstream commit fb452a1aa3fd4034d7999e309c5466ff2d7005aa ] This reverts commit 6d7b857d541ecd1d9bd997c97242d4ef94b19de2. There is a bug in fragmentation codes use of the percpu_counter API, that can cause issues on systems with many CPUs. The frag_mem_limit() just reads the global counter (fbc->count), without considering other CPUs can have upto batch size (130K) that haven't been subtracted yet. Due to the 3MBytes lower thresh limit, this become dangerous at >=24 CPUs (3*1024*1024/130000=24). The correct API usage would be to use __percpu_counter_compare() which does the right thing, and takes into account the number of (online) CPUs and batch size, to account for this and call __percpu_counter_sum() when needed. We choose to revert the use of the lib/percpu_counter API for frag memory accounting for several reasons: 1) On systems with CPUs > 24, the heavier fully locked __percpu_counter_sum() is always invoked, which will be more expensive than the atomic_t that is reverted to. Given systems with more than 24 CPUs are becoming common this doesn't seem like a good option. To mitigate this, the batch size could be decreased and thresh be increased. 2) The add_frag_mem_limit+sub_frag_mem_limit pairs happen on the RX CPU, before SKBs are pushed into sockets on remote CPUs. Given NICs can only hash on L2 part of the IP-header, the NIC-RXq's will likely be limited. Thus, a fair chance that atomic add+dec happen on the same CPU. Revert note that commit 1d6119baf061 ("net: fix percpu memory leaks") removed init_frag_mem_limit() and instead use inet_frags_init_net(). After this revert, inet_frags_uninit_net() becomes empty. Fixes: 6d7b857d541e ("net: use lib/percpu_counter API for fragmentation mem accounting") Fixes: 1d6119baf061 ("net: fix percpu memory leaks") Signed-off-by: Jesper Dangaard Brouer Acked-by: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: fix sparse warning on rt6i_node

2017-09-27T09:00:10+00:00

[ Upstream commit 4e587ea71bf924f7dac621f1351653bd41e446cb ] Commit c5cff8561d2d adds rcu grace period before freeing fib6_node. This generates a new sparse warning on rt->rt6i_node related code: net/ipv6/route.c:1394:30: error: incompatible types in comparison expression (different address spaces) ./include/net/ip6_fib.h:187:14: error: incompatible types in comparison expression (different address spaces) This commit adds "__rcu" tag for rt6i_node and makes sure corresponding rcu API is used for it. After this fix, sparse no longer generates the above warning. Fixes: c5cff8561d2d ("ipv6: add rcu grace period before freeing fib6_node") Signed-off-by: Wei Wang Acked-by: Eric Dumazet Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: add rcu grace period before freeing fib6_node

2017-09-27T09:00:10+00:00

[ Upstream commit c5cff8561d2d0006e972bd114afd51f082fee77c ] We currently keep rt->rt6i_node pointing to the fib6_node for the route. And some functions make use of this pointer to dereference the fib6_node from rt structure, e.g. rt6_check(). However, as there is neither refcount nor rcu taken when dereferencing rt->rt6i_node, it could potentially cause crashes as rt->rt6i_node could be set to NULL by other CPUs when doing a route deletion. This patch introduces an rcu grace period before freeing fib6_node and makes sure the functions that dereference it takes rcu_read_lock(). Note: there is no "Fixes" tag because this bug was there in a very early stage. Signed-off-by: Wei Wang Acked-by: Eric Dumazet Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

cs5536: add support for IDE controller variant

2017-09-13T21:09:45+00:00

commit 591b6bb605785c12a21e8b07a08a277065b655a5 upstream. Several legacy devices such as Geode-based Cisco ASA appliances and DB800 development board do possess CS5536 IDE controller with different PCI id than existing one. Using pata_generic is not always feasible as at least DB800 requires MSR quirk from pata_cs5536 to be used with vendor firmware. Signed-off-by: Andrey Korolyov Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

workqueue: Fix flag collision

2017-09-13T21:09:45+00:00

commit fbf1c41fc0f4d3574ac2377245efd666c1fa3075 upstream. Commit 0a94efb5acbb ("workqueue: implicit ordered attribute should be overridable") introduced a __WQ_ORDERED_EXPLICIT flag but gave it the same value as __WQ_LEGACY. I don't believe these were intended to mean the same thing, so renumber __WQ_ORDERED_EXPLICIT. Fixes: 0a94efb5acbb ("workqueue: implicit ordered attribute should be ...") Signed-off-by: Ben Hutchings Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

cpumask: fix spurious cpumask_of_node() on non-NUMA multi-node configs

2017-09-07T06:34:09+00:00

commit b339752d054fb32863418452dff350a1086885b1 upstream. When !NUMA, cpumask_of_node(@node) equals cpu_online_mask regardless of @node. The assumption seems that if !NUMA, there shouldn't be more than one node and thus reporting cpu_online_mask regardless of @node is correct. However, that assumption was broken years ago to support DISCONTIGMEM and whether a system has multiple nodes or not is separately controlled by NEED_MULTIPLE_NODES. This means that, on a system with !NUMA && NEED_MULTIPLE_NODES, cpumask_of_node() will report cpu_online_mask for all possible nodes, indicating that the CPUs are associated with multiple nodes which is an impossible configuration. This bug has been around forever but doesn't look like it has caused any noticeable symptoms. However, it triggers a WARN recently added to workqueue to verify NUMA affinity configuration. Fix it by reporting empty cpumask on non-zero nodes if !NUMA. Signed-off-by: Tejun Heo Reported-and-tested-by: Geert Uytterhoeven Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

lightnvm: initialize ppa_addr in dev_to_generic_addr()

2017-09-02T05:06:51+00:00

commit 5389a1dfb39786df08d4f6a482bd2734b1b50e33 upstream. The ->reserved bit is not initialized when allocated on stack. This may lead targets to misinterpret the PPA as cached. Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

net_sched: fix order of queue length updates in qdisc_replace()

2017-08-30T08:19:21+00:00

[ Upstream commit 68a66d149a8c78ec6720f268597302883e48e9fa ] This important to call qdisc_tree_reduce_backlog() after changing queue length. Parent qdisc should deactivate class in ->qlen_notify() called from qdisc_tree_reduce_backlog() but this happens only if qdisc->q.qlen in zero. Missed class deactivations leads to crashes/warnings at picking packets from empty qdisc and corrupting state at reactivating this class in future. Signed-off-by: Konstantin Khlebnikov Fixes: 86a7996cc8a0 ("net_sched: introduce qdisc_replace() helper") Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman