pm24.git/Documentation/admin-guide, branch v4.19-rc4

xen/balloon: add runtime control for scrubbing ballooned out pages

2018-09-14T12:51:10Z

Scrubbing pages on initial balloon down can take some time, especially in nested virtualization case (nested EPT is slow). When HVM/PVH guest is started with memory= significantly lower than maxmem=, all the extra pages will be scrubbed before returning to Xen. But since most of them weren't used at all at that point, Xen needs to populate them first (from populate-on-demand pool). In nested virt case (Xen inside KVM) this slows down the guest boot by 15-30s with just 1.5GB needed to be returned to Xen. Add runtime parameter to enable/disable it, to allow initially disabling scrubbing, then enable it back during boot (for example in initramfs). Such usage relies on assumption that a) most pages ballooned out during initial boot weren't used at all, and b) even if they were, very few secrets are in the guest at that time (before any serious userspace kicks in). Convert CONFIG_XEN_SCRUB_PAGES to CONFIG_XEN_SCRUB_PAGES_DEFAULT (also enabled by default), controlling default value for the new runtime switch. Signed-off-by: Marek Marczykowski-Górecki Reviewed-by: Juergen Gross Signed-off-by: Boris Ostrovsky

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

2018-09-09T12:54:05Z

Pull random driver fix from Ted Ts'o: "Fix things so the choice of whether or not to trust RDRAND to initialize the CRNG is configurable via the boot option random.trust_cpu={on,off}" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: make CPU trust a boot parameter

random: make CPU trust a boot parameter

2018-09-01T16:51:54Z

Instead of forcing a distro or other system builder to choose at build time whether the CPU is trusted for CRNG seeding via CONFIG_RANDOM_TRUST_CPU, provide a boot-time parameter for end users to control the choice. The CONFIG will set the default state instead. Signed-off-by: Kees Cook Signed-off-by: Theodore Ts'o

Merge tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2018-08-24T20:10:38Z

Pull IOMMU updates from Joerg Roedel: - PASID table handling updates for the Intel VT-d driver. It implements a global PASID space now so that applications usings multiple devices will just have one PASID. - A new config option to make iommu passthroug mode the default. - New sysfs attribute for iommu groups to export the type of the default domain. - A debugfs interface (for debug only) usable by IOMMU drivers to export internals to user-space. - R-Car Gen3 SoCs support for the ipmmu-vmsa driver - The ARM-SMMU now aborts transactions from unknown devices and devices not attached to any domain. - Various cleanups and smaller fixes all over the place. * tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (42 commits) iommu/omap: Fix cache flushes on L2 table entries iommu: Remove the ->map_sg indirection iommu/arm-smmu-v3: Abort all transactions if SMMU is enabled in kdump kernel iommu/arm-smmu-v3: Prevent any devices access to memory without registration iommu/ipmmu-vmsa: Don't register as BUS IOMMU if machine doesn't have IPMMU-VMSA iommu/ipmmu-vmsa: Clarify supported platforms iommu/ipmmu-vmsa: Fix allocation in atomic context iommu: Add config option to set passthrough as default iommu: Add sysfs attribyte for domain type iommu/arm-smmu-v3: sync the OVACKFLG to PRIQ consumer register iommu/arm-smmu: Error out only if not enough context interrupts iommu/io-pgtable-arm-v7s: Abort allocation when table address overflows the PTE iommu/io-pgtable-arm: Fix pgtable allocation in selftest iommu/vt-d: Remove the obsolete per iommu pasid tables iommu/vt-d: Apply per pci device pasid table in SVA iommu/vt-d: Allocate and free pasid table iommu/vt-d: Per PCI device pasid table interfaces iommu/vt-d: Add for_each_device_domain() helper iommu/vt-d: Move device_domain_info to header iommu/vt-d: Apply global PASID in SVA ...

mm, oom: introduce memory.oom.group

2018-08-22T17:52:45Z

For some workloads an intervention from the OOM killer can be painful. Killing a random task can bring the workload into an inconsistent state. Historically, there are two common solutions for this problem: 1) enabling panic_on_oom, 2) using a userspace daemon to monitor OOMs and kill all outstanding processes. Both approaches have their downsides: rebooting on each OOM is an obvious waste of capacity, and handling all in userspace is tricky and requires a userspace agent, which will monitor all cgroups for OOMs. In most cases an in-kernel after-OOM cleaning-up mechanism can eliminate the necessity of enabling panic_on_oom. Also, it can simplify the cgroup management for userspace applications. This commit introduces a new knob for cgroup v2 memory controller: memory.oom.group. The knob determines whether the cgroup should be treated as an indivisible workload by the OOM killer. If set, all tasks belonging to the cgroup or to its descendants (if the memory cgroup is not a leaf cgroup) are killed together or not at all. To determine which cgroup has to be killed, we do traverse the cgroup hierarchy from the victim task's cgroup up to the OOMing cgroup (or root) and looking for the highest-level cgroup with memory.oom.group set. Tasks with the OOM protection (oom_score_adj set to -1000) are treated as an exception and are never killed. This patch doesn't change the OOM victim selection algorithm. Link: http://lkml.kernel.org/r/20180802003201.817-4-guro@fb.com Signed-off-by: Roman Gushchin Acked-by: Michal Hocko Acked-by: Johannes Weiner Cc: David Rientjes Cc: Tetsuo Handa Cc: Tejun Heo Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: clarify CONFIG_PAGE_POISONING and usage

2018-08-22T17:52:44Z

The Kconfig text for CONFIG_PAGE_POISONING doesn't mention that it has to be enabled explicitly. This updates the documentation for that and adds a note about CONFIG_PAGE_POISONING to the "page_poison" command line docs. While here, change description of CONFIG_PAGE_POISONING_ZERO too, as it's not "random" data, but rather the fixed debugging value that would be used when not zeroing. Additionally removes a stray "bool" in the Kconfig. Link: http://lkml.kernel.org/r/20180725223832.GA43733@beast Signed-off-by: Kees Cook Reviewed-by: Andrew Morton Cc: Jonathan Corbet Cc: Laura Abbott Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'driver-core-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2018-08-18T18:44:53Z

Pull driver core updates from Greg KH: "Here are all of the driver core and related patches for 4.19-rc1. Nothing huge here, just a number of small cleanups and the ability to now stop the deferred probing after init happens. All of these have been in linux-next for a while with only a merge issue reported" * tag 'driver-core-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (21 commits) base: core: Remove WARN_ON from link dependencies check drivers/base: stop new probing during shutdown drivers: core: Remove glue dirs from sysfs earlier driver core: remove unnecessary function extern declare sysfs.h: fix non-kernel-doc comment PM / Domains: Stop deferring probe at the end of initcall iommu: Remove IOMMU_OF_DECLARE iommu: Stop deferring probe at end of initcalls pinctrl: Support stopping deferred probe after initcalls dt-bindings: pinctrl: add a 'pinctrl-use-default' property driver core: allow stopping deferred probe after init driver core: add a debugfs entry to show deferred devices sysfs: Fix internal_create_group() for named group updates base: fix order of OF initialization linux/device.h: fix kernel-doc notation warning Documentation: update firmware loader fallback reference kobject: Replace strncpy with memcpy drivers: base: cacheinfo: use OF property_read_u32 instead of get_property,read_number kernfs: Replace strncpy with memcpy device: Add #define dev_fmt similar to #define pr_fmt ...

Merge tag 'tty-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2018-08-18T17:50:41Z

Pull tty/serial driver updates from Greg KH: "Here is the big tty and serial driver pull request for 4.19-rc1. It's not all that big, just a number of small serial driver updates and fixes, along with some better vt handling for unicode characters for those using braille terminals. All of these patches have been in linux-next for a long time with no reported issues" * tag 'tty-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (73 commits) tty: serial: 8250: Revert NXP SC16C2552 workaround serial: 8250_exar: Read INT0 from slave device, too tty: rocket: Fix possible buffer overwrite on register_PCI serial: 8250_dw: Add ACPI support for uart on Broadcom SoC serial: 8250_dw: always set baud rate in dw8250_set_termios dt-bindings: serial: Add binding for uartlite tty: serial: uartlite: Add support for suspend and resume tty: serial: uartlite: Add clock adaptation tty: serial: uartlite: Add structure for private data serial: sh-sci: Improve support for separate TEI and DRI interrupts serial: sh-sci: Remove SCIx_RZ_SCIFA_REGTYPE serial: sh-sci: Allow for compressed SCIF address serial: sh-sci: Improve interrupts description serial: 8250: Use cached port name directly in messages serial: 8250_exar: Drop unused variable in pci_xr17v35x_setup() vt: drop unused struct vt_struct vt: avoid a VLA in the unicode screen scroll function vt: add /dev/vcsu* to devices.txt vt: coherence validation code for the unicode screen buffer vt: selection: take screen contents from uniscr if available ...

Merge branch 'akpm' (patches from Andrew)

2018-08-17T23:49:31Z

Merge updates from Andrew Morton: - a few misc things - a few Y2038 fixes - ntfs fixes - arch/sh tweaks - ocfs2 updates - most of MM * emailed patches from Andrew Morton : (111 commits) mm/hmm.c: remove unused variables align_start and align_end fs/userfaultfd.c: remove redundant pointer uwq mm, vmacache: hash addresses based on pmd mm/list_lru: introduce list_lru_shrink_walk_irq() mm/list_lru.c: pass struct list_lru_node* as an argument to __list_lru_walk_one() mm/list_lru.c: move locking from __list_lru_walk_one() to its caller mm/list_lru.c: use list_lru_walk_one() in list_lru_walk_node() mm, swap: make CONFIG_THP_SWAP depend on CONFIG_SWAP mm/sparse: delete old sparse_init and enable new one mm/sparse: add new sparse_init_nid() and sparse_init() mm/sparse: move buffer init/fini to the common place mm/sparse: use the new sparse buffer functions in non-vmemmap mm/sparse: abstract sparse buffer allocations mm/hugetlb.c: don't zero 1GiB bootmem pages mm, page_alloc: double zone's batchsize mm/oom_kill.c: document oom_lock mm/hugetlb: remove gigantic page support for HIGHMEM mm, oom: remove sleep from under oom_lock kernel/dma: remove unsupported gfp_mask parameter from dma_alloc_from_contiguous() mm/cma: remove unsupported gfp_mask parameter from cma_alloc() ...

tools/vm/page-types.c: add support for idle page tracking

2018-08-17T23:20:28Z

Add a flag which causes page-types to use the kernels's idle page tracking to mark pages idle. As the tool already prints the idle flag if set, subsequent runs will show which pages have been accessed since last run. [akpm@linux-foundation.org: simplify mark_page_idle()] [chansen3@cisco.com: reorganize mark_page_idle() logic, add docs] Link: http://lkml.kernel.org/r/20180706172237.21691-1-chansen3@cisco.com Link: http://lkml.kernel.org/r/20180612153223.13174-1-chansen3@cisco.com Signed-off-by: Christian Hansen Reviewed-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds