BMC/Intel-BMC/linux.git/kernel/events, branch dev-4.7

perf/core: Use this_cpu_ptr() when stopping AUX events

2016-10-07T13:21:18+00:00

commit 8b6a3fe8fab97716990a3abde1a01fb5a34552a3 upstream. When tearing down an AUX buf for an event via perf_mmap_close(), __perf_event_output_stop() is called on the event's CPU to ensure that trace generation is halted before the process of unmapping and freeing the buffer pages begins. The callback is performed via cpu_function_call(), which ensures that it runs with interrupts disabled and is therefore not preemptible. Unfortunately, the current code grabs the per-cpu context pointer using get_cpu_ptr(), which unnecessarily disables preemption and doesn't pair the call with put_cpu_ptr(), leading to a preempt_count() imbalance and a BUG when freeing the AUX buffer later on: WARNING: CPU: 1 PID: 2249 at kernel/events/ring_buffer.c:539 __rb_free_aux+0x10c/0x120 Modules linked in: [...] Call Trace: [] dump_stack+0x4f/0x72 [] __warn+0xc6/0xe0 [] warn_slowpath_null+0x18/0x20 [] __rb_free_aux+0x10c/0x120 [] rb_free_aux+0x13/0x20 [] perf_mmap_close+0x29e/0x2f0 [] ? perf_iterate_ctx+0xe0/0xe0 [] remove_vma+0x25/0x60 [] exit_mmap+0x106/0x140 [] mmput+0x1c/0xd0 [] do_exit+0x253/0xbf0 [] do_group_exit+0x3e/0xb0 [] get_signal+0x249/0x640 [] do_signal+0x23/0x640 [] ? _raw_write_unlock_irq+0x12/0x30 [] ? _raw_spin_unlock_irq+0x9/0x10 [] ? __schedule+0x2c6/0x710 [] exit_to_usermode_loop+0x74/0x90 [] prepare_exit_to_usermode+0x26/0x30 [] retint_user+0x8/0x10 This patch uses this_cpu_ptr() instead of get_cpu_ptr(), since preemption is already disabled by the caller. Signed-off-by: Will Deacon Reviewed-by: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Vince Weaver Fixes: 95ff4ca26c49 ("perf/core: Free AUX pages in unmap path") Link: http://lkml.kernel.org/r/20160824091905.GA16944@arm.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

perf/core: Fix event_function_local()

2016-09-07T06:34:48+00:00

commit cca2094605efe6ccf43ff2876dd5bccc799202d8 upstream. Vincent reported triggering the WARN_ON_ONCE() in event_function_local(). While thinking through cases I noticed that by using event_function() directly, we miss the inactive case usually handled by event_function_call(). Therefore construct a blend of event_function_call() and event_function() that handles the cases relevant to event_function_local(). Reported-by: Vince Weaver Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Fixes: fae3fde65138 ("perf: Collapse and fix event_function_call() users") Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

uprobes: Fix the memcg accounting

2016-09-07T06:34:47+00:00

commit 6c4687cc17a788a6dd8de3e27dbeabb7cbd3e066 upstream. __replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path, it should only do this if page_check_address() fails. This means that every enable/disable leads to unbalanced mem_cgroup_uncharge() from put_page(old_page), it is trivial to underflow the page_counter->count and trigger OOM. Reported-and-tested-by: Brenden Blanco Signed-off-by: Oleg Nesterov Reviewed-by: Johannes Weiner Acked-by: Michal Hocko Cc: Alexander Shishkin Cc: Alexei Starovoitov Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Vladimir Davydov Fixes: 00501b531c47 ("mm: memcontrol: rewrite charge API") Link: http://lkml.kernel.org/r/20160817153629.GB29724@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

perf/core: Fix pmu::filter_match for SW-led groups

2016-07-07T06:57:57+00:00

The following commit: 66eb579e66ec ("perf: allow for PMU-specific event filtering") added the pmu::filter_match() callback. This was intended to avoid HW constraints on events from resulting in extremely pessimistic scheduling. However, pmu::filter_match() is only called for the leader of each event group. When the leader is a SW event, we do not filter the groups, and may fail at pmu::add() time, and when this happens we'll give up on scheduling any event groups later in the list until they are rotated ahead of the failing group. This can result in extremely sub-optimal event scheduling behaviour, e.g. if running the following on a big.LITTLE platform: $ taskset -c 0 ./perf stat \ -e 'a57{context-switches,armv8_cortex_a57/config=0x11/}' \ -e 'a53{context-switches,armv8_cortex_a53/config=0x11/}' \ ls context-switches (0.00%) armv8_cortex_a57/config=0x11/ (0.00%) 24 context-switches (37.36%) 57589154 armv8_cortex_a53/config=0x11/ (37.36%) Here the 'a53' event group was always eligible to be scheduled, but the 'a57' group never eligible to be scheduled, as the task was always affine to a Cortex-A53 CPU. The SW (group leader) event in the 'a57' group was eligible, but the HW event failed at pmu::add() time, resulting in ctx_flexible_sched_in giving up on scheduling further groups with HW events. One way of avoiding this is to check pmu::filter_match() on siblings as well as the group leader. If any of these fail their pmu::filter_match() call, we must skip the entire group before attempting to add any events. Signed-off-by: Mark Rutland Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Fixes: 66eb579e66ec ("perf: allow for PMU-specific event filtering") Link: http://lkml.kernel.org/r/1465917041-15339-1-git-send-email-mark.rutland@arm.com [ Small readability edits. ] Signed-off-by: Ingo Molnar

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

2016-06-29T18:50:42+00:00

Pull networking fixes from David Miller: "I've been traveling so this accumulates more than week or so of bug fixing. It perhaps looks a little worse than it really is. 1) Fix deadlock in ath10k driver, from Ben Greear. 2) Increase scan timeout in iwlwifi, from Luca Coelho. 3) Unbreak STP by properly reinjecting STP packets back into the stack. Regression fix from Ido Schimmel. 4) Mediatek driver fixes (missing malloc failure checks, leaking of scratch memory, wrong indexing when mapping TX buffers, etc.) from John Crispin. 5) Fix endianness bug in icmpv6_err() handler, from Hannes Frederic Sowa. 6) Fix hashing of flows in UDP in the ruseport case, from Xuemin Su. 7) Fix netlink notifications in ovs for tunnels, delete link messages are never emitted because of how the device registry state is handled. From Nicolas Dichtel. 8) Conntrack module leaks kmemcache on unload, from Florian Westphal. 9) Prevent endless jump loops in nft rules, from Liping Zhang and Pablo Neira Ayuso. 10) Not early enough spinlock initialization in mlx4, from Eric Dumazet. 11) Bind refcount leak in act_ipt, from Cong WANG. 12) Missing RCU locking in HTB scheduler, from Florian Westphal. 13) Several small MACSEC bug fixes from Sabrina Dubroca (missing RCU barrier, using heap for SG and IV, and erroneous use of async flag when allocating AEAD conext.) 14) RCU handling fix in TIPC, from Ying Xue. 15) Pass correct protocol down into ipv4_{update_pmtu,redirect}() in SIT driver, from Simon Horman. 16) Socket timer deadlock fix in TIPC from Jon Paul Maloy. 17) Fix potential deadlock in team enslave, from Ido Schimmel. 18) Memory leak in KCM procfs handling, from Jiri Slaby. 19) ESN generation fix in ipv4 ESP, from Herbert Xu. 20) Fix GFP_KERNEL allocations with locks held in act_ife, from Cong WANG. 21) Use after free in netem, from Eric Dumazet. 22) Uninitialized last assert time in multicast router code, from Tom Goff. 23) Skip raw sockets in sock_diag destruction broadcast, from Willem de Bruijn. 24) Fix link status reporting in thunderx, from Sunil Goutham. 25) Limit resegmentation of retransmit queue so that we do not retransmit too large GSO frames. From Eric Dumazet. 26) Delay bpf program release after grace period, from Daniel Borkmann" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (141 commits) openvswitch: fix conntrack netlink event delivery qed: Protect the doorbell BAR with the write barriers. neigh: Explicitly declare RCU-bh read side critical section in neigh_xmit() e1000e: keep VLAN interfaces functional after rxvlan off cfg80211: fix proto in ieee80211_data_to_8023 for frames without LLC header qlcnic: use the correct ring in qlcnic_83xx_process_rcv_ring_diag() bpf, perf: delay release of BPF prog after grace period net: bridge: fix vlan stats continue counter tcp: do not send too big packets at retransmit time ibmvnic: fix to use list_for_each_safe() when delete items net: thunderx: Fix TL4 configuration for secondary Qsets net: thunderx: Fix link status reporting net/mlx5e: Reorganize ethtool statistics net/mlx5e: Fix number of PFC counters reported to ethtool net/mlx5e: Prevent adding the same vxlan port net/mlx5e: Check for BlueFlame capability before allocating SQ uar net/mlx5e: Change enum to better reflect usage net/mlx5: Add ConnectX-5 PCIe 4.0 to list of supported devices net/mlx5: Update command strings net: marvell: Add separate config ANEG function for Marvell 88E1111 ...

bpf, perf: delay release of BPF prog after grace period

2016-06-29T09:42:55+00:00

Commit dead9f29ddcc ("perf: Fix race in BPF program unregister") moved destruction of BPF program from free_event_rcu() callback to __free_event(), which is problematic if used with tail calls: if prog A is attached as trace event directly, but at the same time present in a tail call map used by another trace event program elsewhere, then we need to delay destruction via RCU grace period since it can still be in use by the program doing the tail call (the prog first needs to be dropped from the tail call map, then trace event with prog A attached destroyed, so we get immediate destruction). Fixes: dead9f29ddcc ("perf: Fix race in BPF program unregister") Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Cc: Jann Horn Signed-off-by: David S. Miller

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-06-10T18:15:41+00:00

Pull perf fixes from Ingo Molnar: "A handful of tooling fixes, two PMU driver fixes and a cleanup of redundant code that addresses a security analyzer false positive" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Remove a redundant check perf/x86/intel/uncore: Remove SBOX support for Broadwell server perf ctf: Convert invalid chars in a string before set value perf record: Fix crash when kptr is restricted perf symbols: Check kptr_restrict for root perf/x86/intel/rapl: Fix pmus free during cleanup

perf/core: Remove a redundant check

2016-06-08T12:30:01+00:00

There is no way to end up in _free_event() with event::pmu being NULL. The latter is initialized in event allocation path and remains set forever. In case of allocation failure, the error path doesn't use _free_event(). Having the check, however, suggests that it is possible to have a event::pmu==NULL situation in _free_event() and confuses the robots. This patch gets rid of the check. Reported-by: Dan Carpenter Signed-off-by: Alexander Shishkin Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: eranian@google.com Cc: vince@deater.net Link: http://lkml.kernel.org/r/1465303455-26032-1-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-05-26T00:05:40+00:00

Pull perf updates from Ingo Molnar: "Mostly tooling and PMU driver fixes, but also a number of late updates such as the reworking of the call-chain size limiting logic to make call-graph recording more robust, plus tooling side changes for the new 'backwards ring-buffer' extension to the perf ring-buffer" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) perf record: Read from backward ring buffer perf record: Rename variable to make code clear perf record: Prevent reading invalid data in record__mmap_read perf evlist: Add API to pause/resume perf trace: Use the ptr->name beautifier as default for "filename" args perf trace: Use the fd->name beautifier as default for "fd" args perf report: Add srcline_from/to branch sort keys perf evsel: Record fd into perf_mmap perf evsel: Add overwrite attribute and check write_backward perf tools: Set buildid dir under symfs when --symfs is provided perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced perf annotate: Sort list of recognised instructions perf annotate: Fix identification of ARM blt and bls instructions perf tools: Fix usage of max_stack sysctl perf callchain: Stop validating callchains by the max_stack sysctl perf trace: Fix exit_group() formatting perf top: Use machine->kptr_restrict_warned perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1 perf machine: Do not bail out if not managing to read ref reloc symbol perf/x86/intel/p4: Trival indentation fix, remove space ...

uprobes: wait for mmap_sem for write killable

2016-05-24T00:04:14+00:00

xol_add_vma needs mmap_sem for write. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Do not warn in dup_xol_work if __create_xol_area failed due to fatal signal pending because this is usually considered a kernel issue. Signed-off-by: Michal Hocko Acked-by: Oleg Nesterov Acked-by: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds