[Feature] Optimize huge page clear/copy cache behavior

Is there a list of commits we should confirm for 18.04?

Can we move this bug to the "Linux" package and make it public?

There are two sub-tasks for this feature.

1) Clear to access sub-page last when clearing huge page(no need backporting)
c79b57e462b5d2f47afa5f175cf1828f16e18612

###
git tag --contains c79b57e462b5d2f47afa5f175cf1828f16e18612
v4.14
###

2) Copy to access sub-page last when copying huge page (need backporting)
5b7a1d406062449a4d51aea1df37a73285ced1dc 974e6d66b6b5c6e2d6a3ccc18b2f9a0b472be5b4 c6ddfb6c58903262d2d77042c41dba58cf775d88 c9f4cd71383576a916e7fca99c490fc92a289f5a

v4.19-rcx

NOTE:
need backporting 2nd sub-task

2) Copy to access sub-page last when copying huge page (need backporting)
5b7a1d406062449a4d51aea1df37a73285ced1dc 974e6d66b6b5c6e2d6a3ccc18b2f9a0b472be5b4 c6ddfb6c58903262d2d77042c41dba58cf775d88 c9f4cd71383576a916e7fca99c490fc92a289f5a

v4.19-rcx

Can we make this bug public?

Thanks.
Cascardo.

I built a test kernel with commits c6ddfb6, c9f4cd7, 5b7a1d4 and 974e6d6. The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1730836

Can you test this kernel and see if it resolves this bug?

Note about installing test kernels:
• If the test kernel is prior to 4.15(Bionic) you need to install the linux-image and linux-image-extra .deb packages.
• If the test kernel is 4.15(Bionic) or newer, you need to install the linux-modules, linux-modules-extra and linux-image-unsigned .deb packages.

Thanks in advance!

Request submitted for Cosmic:
https://lists.ubuntu.com/archives/kernel-team/2018-September/095332.html

This bug was fixed in the package linux - 4.18.0-9.10

---------------
linux (4.18.0-9.10) cosmic; urgency=medium

  * linux: 4.18.0-9.10 -proposed tracker (LP: #1796346)

  * Cosmic update: v4.18.12 upstream stable release (LP: #1796139)
    - crypto: skcipher - Fix -Wstringop-truncation warnings
    - iio: adc: ina2xx: avoid kthread_stop() with stale task_struct
    - tsl2550: fix lux1_input error in low light
    - misc: ibmvmc: Use GFP_ATOMIC under spin lock
    - vmci: type promotion bug in qp_host_get_user_memory()
    - siox: don't create a thread without starting it
    - x86/numa_emulation: Fix emulated-to-physical node mapping
    - staging: rts5208: fix missing error check on call to rtsx_write_register
    - power: supply: axp288_charger: Fix initial constant_charge_current value
    - misc: sram: enable clock before registering regions
    - serial: sh-sci: Stop RX FIFO timer during port shutdown
    - uwb: hwa-rc: fix memory leak at probe
    - power: vexpress: fix corruption in notifier registration
    - iommu/amd: make sure TLB to be flushed before IOVA freed
    - Bluetooth: Add a new Realtek 8723DE ID 0bda:b009
    - USB: serial: kobil_sct: fix modem-status error handling
    - 6lowpan: iphc: reset mac_header after decompress to fix panic
    - iommu/msm: Don't call iommu_device_{,un}link from atomic context
    - s390/mm: correct allocate_pgste proc_handler callback
    - power: remove possible deadlock when unregistering power_supply
    - drm/amd/display/dc/dce: Fix multiple potential integer overflows
    - drm/amd/display: fix use of uninitialized memory
    - md-cluster: clear another node's suspend_area after the copy is finished
    - cxgb4: Fix the condition to check if the card is T5
    - RDMA/bnxt_re: Fix a couple off by one bugs
    - RDMA/i40w: Hold read semaphore while looking after VMA
    - RDMA/bnxt_re: Fix a bunch of off by one bugs in qplib_fp.c
    - IB/core: type promotion bug in rdma_rw_init_one_mr()
    - media: exynos4-is: Prevent NULL pointer dereference in __isp_video_try_fmt()
    - IB/mlx4: Test port number before querying type.
    - powerpc/kdump: Handle crashkernel memory reservation failure
    - media: fsl-viu: fix error handling in viu_of_probe()
    - vhost_net: Avoid tx vring kicks during busyloop
    - media: staging/imx: fill vb2_v4l2_buffer field entry
    - IB/mlx5: Fix GRE flow specification
    - include/rdma/opa_addr.h: Fix an endianness issue
    - x86/tsc: Add missing header to tsc_msr.c
    - ARM: hwmod: RTC: Don't assume lock/unlock will be called with irq enabled
    - x86/entry/64: Add two more instruction suffixes
    - ARM: dts: ls1021a: Add missing cooling device properties for CPUs
    - scsi: target/iscsi: Make iscsit_ta_authentication() respect the output
      buffer size
    - thermal: i.MX: Allow thermal probe to fail gracefully in case of bad
      calibration.
    - scsi: klist: Make it safe to use klists in atomic context
    - scsi: ibmvscsi: Improve strings handling
    - scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion
    - usb: wusbcore: security: cast sizeof to int for comparison
    - ath10k: sdio: use same endpoint id for all packets...

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-bionic' to 'verification-done-bionic'. If the problem still exists, change the tag 'verification-needed-bionic' to 'verification-failed-bionic'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

This bug was erroneously marked for verification in bionic; verification is not required and verification-needed-bionic is being removed.