user/sven/linux.git/include/linux, branch v4.9.10

Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()

2017-02-14T23:25:39Z

commit 433e19cf33d34bb6751c874a9c00980552fe508c upstream. Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") added the proper mb(), but removed the test "prev_write_sz < pending_sz" when making the signal decision. As a result, the guest can signal the host unnecessarily, and then the host can throttle the guest because the host thinks the guest is buggy or malicious; finally the user running stress test can perceive intermittent freeze of the guest. This patch brings back the test, and properly handles the in-place consumption APIs used by NetVSC (see get_next_pkt_raw(), put_pkt_raw() and commit_rd_index()). Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") Signed-off-by: Dexuan Cui Reported-by: Rolf Neugebauer Tested-by: Rolf Neugebauer Cc: "K. Y. Srinivasan" Cc: Haiyang Zhang Cc: Stephen Hemminger Signed-off-by: K. Y. Srinivasan Cc: Rolf Neugebauer Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: On the read path cleanup the logic to interrupt the host

2017-02-14T23:25:38Z

commit 3372592a140db69fd63837e81f048ab4abf8111e upstream. Signal the host when we determine the host is to be signaled - on th read path. The currrent code determines the need to signal in the ringbuffer code and actually issues the signal elsewhere. This can result in the host viewing this interrupt as spurious since the host may also poll the channel. Make the necessary adjustments. Signed-off-by: K. Y. Srinivasan Cc: Rolf Neugebauer Signed-off-by: Greg Kroah-Hartman

Drivers: hv: vmbus: On write cleanup the logic to interrupt the host

2017-02-14T23:25:38Z

commit 1f6ee4e7d83586c8b10bd4f2f4346353d04ce884 upstream. Signal the host when we determine the host is to be signaled. The currrent code determines the need to signal in the ringbuffer code and actually issues the signal elsewhere. This can result in the host viewing this interrupt as spurious since the host may also poll the channel. Make the necessary adjustments. Signed-off-by: K. Y. Srinivasan Cc: Rolf Neugebauer Signed-off-by: Greg Kroah-Hartman

cpumask: use nr_cpumask_bits for parsing functions

2017-02-14T23:25:34Z

commit 4d59b6ccf000862beed6fc0765d3209f98a8d8a2 upstream. Commit 513e3d2d11c9 ("cpumask: always use nr_cpu_ids in formatting and parsing functions") converted both cpumask printing and parsing functions to use nr_cpu_ids instead of nr_cpumask_bits. While this was okay for the printing functions as it just picked one of the two output formats that we were alternating between depending on a kernel config, doing the same for parsing wasn't okay. nr_cpumask_bits can be either nr_cpu_ids or NR_CPUS. We can always use nr_cpu_ids but that is a variable while NR_CPUS is a constant, so it can be more efficient to use NR_CPUS when we can get away with it. Converting the printing functions to nr_cpu_ids makes sense because it affects how the masks get presented to userspace and doesn't break anything; however, using nr_cpu_ids for parsing functions can incorrectly leave the higher bits uninitialized while reading in these masks from userland. As all testing and comparison functions use nr_cpumask_bits which can be larger than nr_cpu_ids, the parsed cpumasks can erroneously yield false negative results. This made the taskstats interface incorrectly return -EINVAL even when the inputs were correct. Fix it by restoring the parse functions to use nr_cpumask_bits instead of nr_cpu_ids. Link: http://lkml.kernel.org/r/20170206182442.GB31078@htj.duckdns.org Fixes: 513e3d2d11c9 ("cpumask: always use nr_cpu_ids in formatting and parsing functions") Signed-off-by: Tejun Heo Reported-by: Martin Steigerwald Debugged-by: Ben Hutchings Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

irqdomain: Avoid activating interrupts more than once

2017-02-09T07:08:31Z

commit 08d85f3ea99f1eeafc4e8507936190e86a16ee8c upstream. Since commit f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early"), we can end-up activating a PCI/MSI twice (once at allocation time, and once at startup time). This is normally of no consequences, except that there is some HW out there that may misbehave if activate is used more than once (the GICv3 ITS, for example, uses the activate callback to issue the MAPVI command, and the architecture spec says that "If there is an existing mapping for the EventID-DeviceID combination, behavior is UNPREDICTABLE"). While this could be worked around in each individual driver, it may make more sense to tackle the issue at the core level. In order to avoid getting in that situation, let's have a per-interrupt flag to remember if we have already activated that interrupt or not. Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early") Reported-and-tested-by: Andre Przywara Signed-off-by: Marc Zyngier Link: http://lkml.kernel.org/r/1484668848-24361-1-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

percpu-refcount: fix reference leak during percpu-atomic transition

2017-02-09T07:08:28Z

commit 966d2b04e070bc040319aaebfec09e0144dc3341 upstream. percpu_ref_tryget() and percpu_ref_tryget_live() should return "true" IFF they acquire a reference. But the return value from atomic_long_inc_not_zero() is a long and may have high bits set, e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines is bool so the reference may actually be acquired but the routines return "false" which results in a reference leak since the caller assumes it does not need to do a corresponding percpu_ref_put(). This was seen when performing CPU hotplug during I/O, as hangs in blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start) raced with percpu_ref_tryget (blk_mq_timeout_work). Sample stack trace: __switch_to+0x2c0/0x450 __schedule+0x2f8/0x970 schedule+0x48/0xc0 blk_mq_freeze_queue_wait+0x94/0x120 blk_mq_queue_reinit_work+0xb8/0x180 blk_mq_queue_reinit_prepare+0x84/0xa0 cpuhp_invoke_callback+0x17c/0x600 cpuhp_up_callbacks+0x58/0x150 _cpu_up+0xf0/0x1c0 do_cpu_up+0x120/0x150 cpu_subsys_online+0x64/0xe0 device_online+0xb4/0x120 online_store+0xb4/0xc0 dev_attr_store+0x68/0xa0 sysfs_kf_write+0x80/0xb0 kernfs_fop_write+0x17c/0x250 __vfs_write+0x6c/0x1e0 vfs_write+0xd0/0x270 SyS_write+0x6c/0x110 system_call+0x38/0xe0 Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS, and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests. However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0 and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set. The fix is to make the tryget routines use an actual boolean internally instead of the atomic long result truncated to a int. Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751 Signed-off-by: Douglas Miller Reviewed-by: Jens Axboe Signed-off-by: Tejun Heo Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints") Signed-off-by: Greg Kroah-Hartman

base/memory, hotplug: fix a kernel oops in show_valid_zones()

2017-02-09T07:08:28Z

commit a96dfddbcc04336bbed50dc2b24823e45e09e80c upstream. Reading a sysfs "memoryN/valid_zones" file leads to the following oops when the first page of a range is not backed by struct page. show_valid_zones() assumes that 'start_pfn' is always valid for page_zone(). BUG: unable to handle kernel paging request at ffffea017a000000 IP: show_valid_zones+0x6f/0x160 This issue may happen on x86-64 systems with 64GiB or more memory since their memory block size is bumped up to 2GiB. [1] An example of such systems is desribed below. 0x3240000000 is only aligned by 1GiB and this memory block starts from 0x3200000000, which is not backed by struct page. BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable Since test_pages_in_a_zone() already checks holes, fix this issue by extending this function to return 'valid_start' and 'valid_end' for a given range. show_valid_zones() then proceeds with the valid range. [1] 'Commit bdee237c0343 ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems")' Link: http://lkml.kernel.org/r/20170127222149.30893-3-toshi.kani@hpe.com Signed-off-by: Toshi Kani Cc: Greg Kroah-Hartman Cc: Zhang Zhen Cc: Reza Arbab Cc: David Rientjes Cc: Dan Williams Signed-off-by: Greg Kroah-Hartman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

virtio-net: restore VIRTIO_HDR_F_DATA_VALID on receiving

2017-02-04T08:47:09Z

[ Upstream commit 6391a4481ba0796805d6581e42f9f0418c099e34 ] Commit 501db511397f ("virtio: don't set VIRTIO_NET_HDR_F_DATA_VALID on xmit") in fact disables VIRTIO_HDR_F_DATA_VALID on receiving path too, fixing this by adding a hint (has_data_valid) and set it only on the receiving path. Cc: Rolf Neugebauer Signed-off-by: Jason Wang Acked-by: Rolf Neugebauer Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

virtio: don't set VIRTIO_NET_HDR_F_DATA_VALID on xmit

2017-02-04T08:47:09Z

[ Upstream commit 501db511397fd6efff3aa5b4e8de415b55559550 ] This patch part reverts fd2a0437dc33 and e858fae2b0b8 which introduced a subtle change in how the virtio_net flags are derived from the SKBs ip_summed field. With the above commits, the flags are set to VIRTIO_NET_HDR_F_DATA_VALID when ip_summed == CHECKSUM_UNNECESSARY, thus treating it differently to ip_summed == CHECKSUM_NONE, which should be the same. Further, the virtio spec 1.0 / CS04 explicitly says that VIRTIO_NET_HDR_F_DATA_VALID must not be set by the driver. Fixes: fd2a0437dc33 ("virtio_net: introduce virtio_net_hdr_{from,to}_skb") Fixes: e858fae2b0b8 (" virtio_net: use common code for virtio_net_hdr and skb GSO conversion") Signed-off-by: Rolf Neugebauer Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: fix tcp_fastopen unaligned access complaints on sparc

2017-02-04T08:47:09Z

[ Upstream commit 003c941057eaa868ca6fedd29a274c863167230d ] Fix up a data alignment issue on sparc by swapping the order of the cookie byte array field with the length field in struct tcp_fastopen_cookie, and making it a proper union to clean up the typecasting. This addresses log complaints like these: log_unaligned: 113 callbacks suppressed Kernel unaligned access at TPC[976490] tcp_try_fastopen+0x2d0/0x360 Kernel unaligned access at TPC[9764ac] tcp_try_fastopen+0x2ec/0x360 Kernel unaligned access at TPC[9764c8] tcp_try_fastopen+0x308/0x360 Kernel unaligned access at TPC[9764e4] tcp_try_fastopen+0x324/0x360 Kernel unaligned access at TPC[976490] tcp_try_fastopen+0x2d0/0x360 Cc: Eric Dumazet Signed-off-by: Shannon Nelson Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman