user/sven/linux.git/include, branch v4.20.11

mmc: block: handle complete_work on separate workqueue

2019-02-20T09:29:11Z

commit dcf6e2e38a1c7ccbc535de5e1d9b14998847499d upstream. The kblockd workqueue is created with the WQ_MEM_RECLAIM flag set. This generates a rescuer thread for that queue that will trigger when the CPU is under heavy load and collect the uncompleted work. In the case of mmc, this creates the possibility of a deadlock when there are multiple partitions on the device as other blk-mq work is also run on the same queue. For example: - worker 0 claims the mmc host to work on partition 1 - worker 1 attempts to claim the host for partition 2 but has to wait for worker 0 to finish - worker 0 schedules complete_work to release the host - rescuer thread is triggered after time-out and collects the dangling work - rescuer thread attempts to complete the work in order starting with claim host - the task to release host is now blocked by a task to claim it and will never be called The above results in multiple hung tasks that lead to failures to mount partitions. Handling complete_work on a separate workqueue avoids this by keeping the work completion tasks separate from the other blk-mq work. This allows the host to be released without getting blocked by other tasks attempting to claim the host. Signed-off-by: Zachary Hays Fixes: 81196976ed94 ("mmc: block: Add blk-mq support") Cc: Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman

perf/x86: Add check_period PMU callback

2019-02-20T09:29:10Z

commit 81ec3f3c4c4d78f2d3b6689c9816bfbdf7417dbb upstream. Vince (and later on Ravi) reported crashes in the BTS code during fuzzing with the following backtrace: general protection fault: 0000 [#1] SMP PTI ... RIP: 0010:perf_prepare_sample+0x8f/0x510 ... Call Trace: ? intel_pmu_drain_bts_buffer+0x194/0x230 intel_pmu_drain_bts_buffer+0x160/0x230 ? tick_nohz_irq_exit+0x31/0x40 ? smp_call_function_single_interrupt+0x48/0xe0 ? call_function_single_interrupt+0xf/0x20 ? call_function_single_interrupt+0xa/0x20 ? x86_schedule_events+0x1a0/0x2f0 ? x86_pmu_commit_txn+0xb4/0x100 ? find_busiest_group+0x47/0x5d0 ? perf_event_set_state.part.42+0x12/0x50 ? perf_mux_hrtimer_restart+0x40/0xb0 intel_pmu_disable_event+0xae/0x100 ? intel_pmu_disable_event+0xae/0x100 x86_pmu_stop+0x7a/0xb0 x86_pmu_del+0x57/0x120 event_sched_out.isra.101+0x83/0x180 group_sched_out.part.103+0x57/0xe0 ctx_sched_out+0x188/0x240 ctx_resched+0xa8/0xd0 __perf_event_enable+0x193/0x1e0 event_function+0x8e/0xc0 remote_function+0x41/0x50 flush_smp_call_function_queue+0x68/0x100 generic_smp_call_function_single_interrupt+0x13/0x30 smp_call_function_single_interrupt+0x3e/0xe0 call_function_single_interrupt+0xf/0x20 The reason is that while event init code does several checks for BTS events and prevents several unwanted config bits for BTS event (like precise_ip), the PERF_EVENT_IOC_PERIOD allows to create BTS event without those checks being done. Following sequence will cause the crash: If we create an 'almost' BTS event with precise_ip and callchains, and it into a BTS event it will crash the perf_prepare_sample() function because precise_ip events are expected to come in with callchain data initialized, but that's not the case for intel_pmu_drain_bts_buffer() caller. Adding a check_period callback to be called before the period is changed via PERF_EVENT_IOC_PERIOD. It will deny the change if the event would become BTS. Plus adding also the limit_period check as well. Reported-by: Vince Weaver Signed-off-by: Jiri Olsa Acked-by: Peter Zijlstra Cc: Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Naveen N. Rao Cc: Ravi Bangoria Cc: Stephane Eranian Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20190204123532.GA4794@krava Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

cpu/hotplug: Fix "SMT disabled by BIOS" detection for KVM

2019-02-12T19:02:37Z

commit b284909abad48b07d3071a9fc9b5692b3e64914b upstream. With the following commit: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS") ... the hotplug code attempted to detect when SMT was disabled by BIOS, in which case it reported SMT as permanently disabled. However, that code broke a virt hotplug scenario, where the guest is booted with only primary CPU threads, and a sibling is brought online later. The problem is that there doesn't seem to be a way to reliably distinguish between the HW "SMT disabled by BIOS" case and the virt "sibling not yet brought online" case. So the above-mentioned commit was a bit misguided, as it permanently disabled SMT for both cases, preventing future virt sibling hotplugs. Going back and reviewing the original problems which were attempted to be solved by that commit, when SMT was disabled in BIOS: 1) /sys/devices/system/cpu/smt/control showed "on" instead of "notsupported"; and 2) vmx_vm_init() was incorrectly showing the L1TF_MSG_SMT warning. I'd propose that we instead consider #1 above to not actually be a problem. Because, at least in the virt case, it's possible that SMT wasn't disabled by BIOS and a sibling thread could be brought online later. So it makes sense to just always default the smt control to "on" to allow for that possibility (assuming cpuid indicates that the CPU supports SMT). The real problem is #2, which has a simple fix: change vmx_vm_init() to query the actual current SMT state -- i.e., whether any siblings are currently online -- instead of looking at the SMT "control" sysfs value. So fix it by: a) reverting the original "fix" and its followup fix: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS") bc2d8d262cba ("cpu/hotplug: Fix SMT supported evaluation") and b) changing vmx_vm_init() to query the actual current SMT state -- instead of the sysfs control value -- to determine whether the L1TF warning is needed. This also requires the 'sched_smt_present' variable to exported, instead of 'cpu_smt_control'. Fixes: 73d5e2b47264 ("cpu/hotplug: detect SMT disabled by BIOS") Reported-by: Igor Mammedov Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner Cc: Joe Mario Cc: Jiri Kosina Cc: Peter Zijlstra Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/e3a85d585da28cc333ecbc1e78ee9216e6da9396.1548794349.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman

HID: debug: fix the ring buffer implementation

2019-02-12T19:02:36Z

commit 13054abbaa4f1fd4e6f3b4b63439ec033b4c8035 upstream. Ring buffer implementation in hid_debug_event() and hid_debug_events_read() is strange allowing lost or corrupted data. After commit 717adfdaf147 ("HID: debug: check length before copy_to_user()") it is possible to enter an infinite loop in hid_debug_events_read() by providing 0 as count, this locks up a system. Fix this by rewriting the ring buffer implementation with kfifo and simplify the code. This fixes CVE-2019-3819. v2: fix an execution logic and add a comment v3: use __set_current_state() instead of set_current_state() Link: https://bugzilla.redhat.com/show_bug.cgi?id=1669187 Cc: stable@vger.kernel.org # v4.18+ Fixes: cd667ce24796 ("HID: use debugfs for events/reports dumping") Fixes: 717adfdaf147 ("HID: debug: check length before copy_to_user()") Signed-off-by: Vladis Dronov Reviewed-by: Oleg Nesterov Signed-off-by: Benjamin Tissoires Signed-off-by: Greg Kroah-Hartman

ALSA: hda - Serialize codec registrations

2019-02-12T19:02:35Z

commit 305a0ade180981686eec1f92aa6252a7c6ebb1cf upstream. In the current code, the codec registration may happen both at the codec bind time and the end of the controller probe time. In a rare occasion, they race with each other, leading to Oops due to the still uninitialized card device. This patch introduces a simple flag to prevent the codec registration at the codec bind time as long as the controller probe is going on. The controller probe invokes snd_card_register() that does the whole registration task, and we don't need to register each piece beforehand. Cc: Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: compress: Fix stop handling on compressed capture streams

2019-02-12T19:02:34Z

commit 4f2ab5e1d13d6aa77c55f4914659784efd776eb4 upstream. It is normal user behaviour to start, stop, then start a stream again without closing it. Currently this works for compressed playback streams but not capture ones. The states on a compressed capture stream go directly from OPEN to PREPARED, unlike a playback stream which moves to SETUP and waits for a write of data before moving to PREPARED. Currently however, when a stop is sent the state is set to SETUP for both types of streams. This leaves a capture stream in the situation where a new start can't be sent as that requires the state to be PREPARED and a new set_params can't be sent as that requires the state to be OPEN. The only option being to close the stream, and then reopen. Correct this issues by allowing snd_compr_drain_notify to set the state depending on the stream direction, as we already do in set_params. Fixes: 49bb6402f1aa ("ALSA: compress_core: Add support for capture streams") Signed-off-by: Charles Keepax Cc: Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

kvm: Change offset in kvm_write_guest_offset_cached to unsigned

2019-02-12T19:02:27Z

[ Upstream commit 7a86dab8cf2f0fdf508f3555dddfc236623bff60 ] Since the offset is added directly to the hva from the gfn_to_hva_cache, a negative offset could result in an out of bounds write. The existing BUG_ON only checks for addresses beyond the end of the gfn_to_hva_cache, not for addresses before the start of the gfn_to_hva_cache. Note that all current call sites have non-negative offsets. Fixes: 4ec6e8636256 ("kvm: Introduce kvm_write_guest_offset_cached()") Reported-by: Cfir Cohen Signed-off-by: Jim Mattson Reviewed-by: Cfir Cohen Reviewed-by: Peter Shier Reviewed-by: Krish Sadhukhan Reviewed-by: Sean Christopherson Signed-off-by: Radim Krčmář Signed-off-by: Sasha Levin

bpf: sk_msg, fix socket data_ready events

2019-02-12T19:02:26Z

[ Upstream commit 552de91068828daef50a227a665068cf8dde835e ] When a skb verdict program is in-use and either another BPF program redirects to that socket or the new SK_PASS support is used the data_ready callback does not wake up application. Instead because the stream parser/verdict is using the sk data_ready callback we wake up the stream parser/verdict block. Fix this by adding a helper to check if the stream parser block is enabled on the sk and if so call the saved pointer which is the upper layers wake up function. This fixes application stalls observed when an application is waiting for data in a blocking read(). Fixes: d829e9c4112b ("tls: convert to generic sk_msg interface") Signed-off-by: John Fastabend Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin

drbd: Avoid Clang warning about pointless switch statment

2019-02-12T19:02:25Z

[ Upstream commit a52c5a16cf19d8a85831bb1b915a221dd4ffae3c ] There are several warnings from Clang about no case statement matching the constant 0: In file included from drivers/block/drbd/drbd_receiver.c:48: In file included from drivers/block/drbd/drbd_int.h:48: In file included from ./include/linux/drbd_genl_api.h:54: In file included from ./include/linux/genl_magic_struct.h:236: ./include/linux/drbd_genl.h:321:1: warning: no case matching constant switch condition '0' GENL_struct(DRBD_NLA_HELPER, 24, drbd_helper_info, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/genl_magic_struct.h:220:10: note: expanded from macro 'GENL_struct' switch (0) { ^ Silence this warning by adding a 'case 0:' statement. Additionally, adjust the alignment of the statements in the ct_assert_unique macro to avoid a checkpatch warning. This solution was originally sent by Arnd Bergmann with a default case statement: https://lore.kernel.org/patchwork/patch/756723/ Link: https://github.com/ClangBuiltLinux/linux/issues/43 Suggested-by: Lars Ellenberg Signed-off-by: Nathan Chancellor Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

RDMA/core: Sync unregistration with netlink commands

2019-02-12T19:02:10Z

[ Upstream commit 01b671170d7f82b959dad6d5dbb44d7a915e647d ] When the rdma device is getting removed, get resource info can race with device removal, as below: CPU-0 CPU-1 -------- -------- rdma_nl_rcv_msg() nldev_res_get_cq_dumpit() mutex_lock(device_lock); get device reference mutex_unlock(device_lock); [..] ib_unregister_device() /* Valid reference to * device->dev exists. */ ib_dealloc_device() [..] provider->fill_res_entry(); Even though device object is not freed, fill_res_entry() can get called on device which doesn't have a driver anymore. Kernel core device reference count is not sufficient, as this only keeps the structure valid, and doesn't guarantee the driver is still loaded. Similar race can occur with device renaming and device removal, where device_rename() tries to rename a unregistered device. While this is fine for devices of a class which are not net namespace aware, but it is incorrect for net namespace aware class coming in subsequent series. If a class is net namespace aware, then the below [1] call trace is observed in above situation. Therefore, to avoid the race, keep a reference count and let device unregistration wait until all netlink users drop the reference. [1] Call trace: kernfs: ns required in 'infiniband' for 'mlx5_0' WARNING: CPU: 18 PID: 44270 at fs/kernfs/dir.c:842 kernfs_find_ns+0x104/0x120 libahci i2c_core mlxfw libata dca [last unloaded: devlink] RIP: 0010:kernfs_find_ns+0x104/0x120 Call Trace: kernfs_find_and_get_ns+0x2e/0x50 sysfs_rename_link_ns+0x40/0xb0 device_rename+0xb2/0xf0 ib_device_rename+0xb3/0x100 [ib_core] nldev_set_doit+0x165/0x190 [ib_core] rdma_nl_rcv_msg+0x249/0x250 [ib_core] ? netlink_deliver_tap+0x8f/0x3e0 rdma_nl_rcv+0xd6/0x120 [ib_core] netlink_unicast+0x17c/0x230 netlink_sendmsg+0x2f0/0x3e0 sock_sendmsg+0x30/0x40 __sys_sendto+0xdc/0x160 Fixes: da5c85078215 ("RDMA/nldev: add driver-specific resource tracking") Signed-off-by: Parav Pandit Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin