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2023-09-04Merge tag 'hyperv-next-signed-20230902' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - Support for SEV-SNP guests on Hyper-V (Tianyu Lan) - Support for TDX guests on Hyper-V (Dexuan Cui) - Use SBRM API in Hyper-V balloon driver (Mitchell Levy) - Avoid dereferencing ACPI root object handle in VMBus driver (Maciej Szmigiero) - A few misecllaneous fixes (Jiapeng Chong, Nathan Chancellor, Saurabh Sengar) * tag 'hyperv-next-signed-20230902' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (24 commits) x86/hyperv: Remove duplicate include x86/hyperv: Move the code in ivm.c around to avoid unnecessary ifdef's x86/hyperv: Remove hv_isolation_type_en_snp x86/hyperv: Use TDX GHCI to access some MSRs in a TDX VM with the paravisor Drivers: hv: vmbus: Bring the post_msg_page back for TDX VMs with the paravisor x86/hyperv: Introduce a global variable hyperv_paravisor_present Drivers: hv: vmbus: Support >64 VPs for a fully enlightened TDX/SNP VM x86/hyperv: Fix serial console interrupts for fully enlightened TDX guests Drivers: hv: vmbus: Support fully enlightened TDX guests x86/hyperv: Support hypercalls for fully enlightened TDX guests x86/hyperv: Add hv_isolation_type_tdx() to detect TDX guests x86/hyperv: Fix undefined reference to isolation_type_en_snp without CONFIG_HYPERV x86/hyperv: Add missing 'inline' to hv_snp_boot_ap() stub hv: hyperv.h: Replace one-element array with flexible-array member Drivers: hv: vmbus: Don't dereference ACPI root object handle x86/hyperv: Add hyperv-specific handling for VMMCALL under SEV-ES x86/hyperv: Add smp support for SEV-SNP guest clocksource: hyper-v: Mark hyperv tsc page unencrypted in sev-snp enlightened guest x86/hyperv: Use vmmcall to implement Hyper-V hypercall in sev-snp enlightened guest drivers: hv: Mark percpu hvcall input arg page unencrypted in SEV-SNP enlightened guest ...
2023-08-11hv_balloon: Update the balloon driver to use the SBRM APIMitchell Levy
This patch is intended as a proof-of-concept for the new SBRM machinery[1]. For some brief background, the idea behind SBRM is using the __cleanup__ attribute to automatically unlock locks (or otherwise release resources) when they go out of scope, similar to C++ style RAII. This promises some benefits such as making code simpler (particularly where you have lots of goto fail; type constructs) as well as reducing the surface area for certain kinds of bugs. The changes in this patch should not result in any difference in how the code actually runs (i.e., it's purely an exercise in this new syntax sugar). In one instance SBRM was not appropriate, so I left that part alone, but all other locking/unlocking is handled automatically in this patch. [1] https://lore.kernel.org/all/20230626125726.GU4253@hirez.programming.kicks-ass.net/ Suggested-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: "Mitchell Levy (Microsoft)" <levymitchell0@gmail.com> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230807-sbrm-hyperv-v2-1-9d2ac15305bd@gmail.com
2023-06-28x86/hyperv: Improve code for referencing hyperv_pcpu_input_argNischala Yelchuri
Several places in code for Hyper-V reference the per-CPU variable hyperv_pcpu_input_arg. Older code uses a multi-line sequence to reference the variable, and usually includes a cast. Newer code does a much simpler direct assignment. The latter is preferable as the complexity of the older code is unnecessary. Update older code to use the simpler direct assignment. Signed-off-by: Nischala Yelchuri <niyelchu@linux.microsoft.com> Link: https://lore.kernel.org/r/1687286438-9421-1-git-send-email-niyelchu@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-02-21Merge tag 'hyperv-next-signed-20230220' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - allow Linux to run as the nested root partition for Microsoft Hypervisor (Jinank Jain and Nuno Das Neves) - clean up the return type of callback functions (Dawei Li) * tag 'hyperv-next-signed-20230220' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: Fix hv_get/set_register for nested bringup Drivers: hv: Make remove callback of hyperv driver void returned Drivers: hv: Enable vmbus driver for nested root partition x86/hyperv: Add an interface to do nested hypercalls Drivers: hv: Setup synic registers in case of nested root partition x86/hyperv: Add support for detecting nested hypervisor
2023-02-03HV: hv_balloon: fix memory leak with using debugfs_lookup()Greg Kroah-Hartman
When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Dexuan Cui <decui@microsoft.com> Fixes: d180e0a1be6c ("Drivers: hv: Create debugfs file with hyper-v balloon usage information") Cc: stable <stable@kernel.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20230202140918.2289522-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-17Drivers: hv: Make remove callback of hyperv driver void returnedDawei Li
Since commit fc7a6209d571 ("bus: Make remove callback return void") forces bus_type::remove be void-returned, it doesn't make much sense for any bus based driver implementing remove callbalk to return non-void to its caller. As such, change the remove function for Hyper-V VMBus based drivers to return void. Signed-off-by: Dawei Li <set_pte_at@outlook.com> Link: https://lore.kernel.org/r/TYCP286MB2323A93C55526E4DF239D3ACCAFA9@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-11-28hv_balloon: Add support for configurable order free page reportingShradha Gupta
Newer versions of Hyper-V allow reporting unused guest pages in chunks smaller than 2 Mbytes. Using smaller chunks allows reporting more unused guest pages, but with increased overhead in the finding the small chunks. To make this tradeoff configurable, use the existing page_reporting_order module parameter to control the reporting order. Drop and refine checks that restricted the minimun page reporting order to 2Mbytes size pages. Add appropriate checks to make sure the underlying Hyper-V versions support cold discard hints of any order (and not just starting from 9) Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1664517699-1085-3-git-send-email-shradhagupta@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-10-27Drivers: hv: fix repeated words in commentsJilin Yuan
Delete the redundant word 'of'. Signed-off-by: Jilin Yuan <yuanjilin@cdjrlc.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20221019125604.52999-1-yuanjilin@cdjrlc.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-07-18Drivers: hv: Create debugfs file with hyper-v balloon usage informationAlexander Atanasov
Allow the guest to know how much it is ballooned by the host. It is useful when debugging out of memory conditions. When host gets back memory from the guest it is accounted as used memory in the guest but the guest have no way to know how much it is actually ballooned. Expose current state, flags and max possible memory to the guest. While at it - fix a 10+ years old typo. Signed-off-by: Alexander Atanasov <alexander.atanasov@virtuozzo.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220711181825.52318-1-alexander.atanasov@virtuozzo.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-05-26hv_balloon: Fix balloon_probe() and balloon_remove() error handlingShradha Gupta
Add missing cleanup in balloon_probe() if the call to balloon_connect_vsp() fails. Also correctly handle cleanup in balloon_remove() when dm_state is DM_INIT_ERROR because balloon_resume() failed. Signed-off-by: Shradha Gupta <shradhagupta@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220516045058.GA7933@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-04-07Merge tag 'hyperv-fixes-signed-20220407' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - Correctly propagate coherence information for VMbus devices (Michael Kelley) - Disable balloon and memory hot-add on ARM64 temporarily (Boqun Feng) - Use barrier to prevent reording when reading ring buffer (Michael Kelley) - Use virt_store_mb in favour of smp_store_mb (Andrea Parri) - Fix VMbus device object initialization (Andrea Parri) - Deactivate sysctl_record_panic_msg on isolated guest (Andrea Parri) - Fix a crash when unloading VMbus module (Guilherme G. Piccoli) * tag 'hyperv-fixes-signed-20220407' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: Drivers: hv: vmbus: Replace smp_store_mb() with virt_store_mb() Drivers: hv: balloon: Disable balloon and hot-add accordingly Drivers: hv: balloon: Support status report for larger page sizes Drivers: hv: vmbus: Prevent load re-ordering when reading ring buffer PCI: hv: Propagate coherence from VMbus device to PCI device Drivers: hv: vmbus: Propagate VMbus coherence to each VMbus device Drivers: hv: vmbus: Fix potential crash on module unload Drivers: hv: vmbus: Fix initialization of device object in vmbus_device_register() Drivers: hv: vmbus: Deactivate sysctl_record_panic_msg by default in isolated guests
2022-04-06Drivers: hv: balloon: Disable balloon and hot-add accordinglyBoqun Feng
Currently there are known potential issues for balloon and hot-add on ARM64: * Unballoon requests from Hyper-V should only unballoon ranges that are guest page size aligned, otherwise guests cannot handle because it's impossible to partially free a page. This is a problem when guest page size > 4096 bytes. * Memory hot-add requests from Hyper-V should provide the NUMA node id of the added ranges or ARM64 should have a functional memory_add_physaddr_to_nid(), otherwise the node id is missing for add_memory(). These issues require discussions on design and implementation. In the meanwhile, post_status() is working and essential to guest monitoring. Therefore instead of disabling the entire hv_balloon driver, the ballooning (when page size > 4096 bytes) and hot-add are disabled accordingly for now. Once the issues are fixed, they can be re-enable in these cases. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220325023212.1570049-3-boqun.feng@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-04-06Drivers: hv: balloon: Support status report for larger page sizesBoqun Feng
DM_STATUS_REPORT expects the numbers of pages in the unit of 4k pages (HV_HYP_PAGE) instead of guest pages, so to make it work when guest page sizes are larger than 4k, convert the numbers of guest pages into the numbers of HV_HYP_PAGEs. Note that the numbers of guest pages are still used for tracing because tracing is internal to the guest kernel. Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220325023212.1570049-2-boqun.feng@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-03-01hv_balloon: rate-limit "Unhandled message" warningAnssi Hannula
For a couple of times I have encountered a situation where hv_balloon: Unhandled message: type: 12447 is being flooded over 1 million times per second with various values, filling the log and consuming cycles, making debugging difficult. Add rate limiting to the message. Most other Hyper-V drivers already have similar rate limiting in their message callbacks. The cause of the floods in my case was probably fixed by 96d9d1fa5cd5 ("Drivers: hv: balloon: account for vmbus packet header in max_pkt_size"). Fixes: 9aa8b50b2b3d ("Drivers: hv: Add Hyper-V balloon driver") Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220222141400.98160-1-anssi.hannula@bitwise.fi Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-01-23Drivers: hv: balloon: account for vmbus packet header in max_pkt_sizeYanming Liu
Commit adae1e931acd ("Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer") introduced a notion of maximum packet size in vmbus channel and used that size to initialize a buffer holding all incoming packet along with their vmbus packet header. hv_balloon uses the default maximum packet size VMBUS_DEFAULT_MAX_PKT_SIZE which matches its maximum message size, however vmbus_open expects this size to also include vmbus packet header. This leads to 4096 bytes dm_unballoon_request messages being truncated to 4080 bytes. When the driver tries to read next packet it starts from a wrong read_index, receives garbage and prints a lot of "Unhandled message: type: <garbage>" in dmesg. Allocate the buffer with HV_HYP_PAGE_SIZE more bytes to make room for the header. Fixes: adae1e931acd ("Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer") Suggested-by: Michael Kelley (LINUX) <mikelley@microsoft.com> Suggested-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Signed-off-by: Yanming Liu <yanminglr@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20220119202052.3006981-1-yanminglr@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-11-15Drivers: hv: balloon: Use VMBUS_RING_SIZE() wrapper for dm_ring_sizeBoqun Feng
Baihua reported an error when boot an ARM64 guest with PAGE_SIZE=64k and BALLOON is enabled: hv_vmbus: registering driver hv_balloon hv_vmbus: probe failed for device 1eccfd72-4b41-45ef-b73a-4a6e44c12924 (-22) The cause of this is that the ringbuffer size for hv_balloon is not adjusted with VMBUS_RING_SIZE(), which makes the size not large enough for ringbuffers on guest with PAGE_SIZE=64k. Therefore use VMBUS_RING_SIZE() to calculate the ringbuffer size. Note that the old size (20 * 1024) counts a 4k header in the total size, while VMBUS_RING_SIZE() expects the parameter as the payload size, so use 16 * 1024. Cc: <stable@vger.kernel.org> # 5.15.x Reported-by: Baihua Lu <baihua.lu@microsoft.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20211101150026.736124-1-boqun.feng@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-05-14hv_balloon: Remove redundant assignment to region_startJiapeng Chong
Variable region_start is set to pg_start but this value is never read as it is overwritten later on, hence it is a redundant assignment and can be removed. Cleans up the following clang-analyzer warning: drivers/hv/hv_balloon.c:1013:3: warning: Value stored to 'region_start' is never read [clang-analyzer-deadcode.DeadStores]. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Link: https://lore.kernel.org/r/1619691681-86256-1-git-send-email-jiapeng.chong@linux.alibaba.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-03-24x86/Hyper-V: Support for free page reportingSunil Muthuswamy
Linux has support for free page reporting now (36e66c554b5c) for virtualized environment. On Hyper-V when virtually backed VMs are configured, Hyper-V will advertise cold memory discard capability, when supported. This patch adds the support to hook into the free page reporting infrastructure and leverage the Hyper-V cold memory discard hint hypercall to report/free these pages back to the host. Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com> Tested-by: Matheus Castello <matheus@castello.eng.br> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/SN4PR2101MB0880121FA4E2FEC67F35C1DCC0649@SN4PR2101MB0880.namprd21.prod.outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-02-26mm/memory_hotplug: MEMHP_MERGE_RESOURCE -> MHP_MERGE_RESOURCEDavid Hildenbrand
Let's make "MEMHP_MERGE_RESOURCE" consistent with "MHP_NONE", "mhp_t" and "mhp_flags". As discussed recently [1], "mhp" is our internal acronym for memory hotplug now. [1] https://lore.kernel.org/linux-mm/c37de2d0-28a1-4f7d-f944-cfd7d81c334d@redhat.com/ Link: https://lkml.kernel.org/r/20210126115829.10909-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Wei Liu <wei.liu@kernel.org> Reviewed-by: Pankaj Gupta <pankaj.gupta@cloud.ionos.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-13hv_balloon: do adjust_managed_page_count() when ballooning/un-ballooningVitaly Kuznetsov
Unlike virtio_balloon/virtio_mem/xen balloon drivers, Hyper-V balloon driver does not adjust managed pages count when ballooning/un-ballooning and this leads to incorrect stats being reported, e.g. unexpected 'free' output. Note, the calculation in post_status() seems to remain correct: ballooned out pages are never 'available' and we manually add dm->num_pages_ballooned to 'commited'. Suggested-by: David Hildenbrand <david@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201202161245.2406143-3-vkuznets@redhat.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-12-13hv_balloon: simplify math in alloc_balloon_pages()Vitaly Kuznetsov
'alloc_unit' in alloc_balloon_pages() is either '512' for 2M allocations or '1' for 4k allocations. So 1 << get_order(alloc_unit << PAGE_SHIFT) equals to 'alloc_unit' and the for loop basically sets all them offline. Simplify the math to improve the readability. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20201202161245.2406143-2-vkuznets@redhat.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-11-05Merge tag 'hyperv-fixes-signed' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - clarify a comment (Michael Kelley) - change a pr_warn() to pr_info() (Olaf Hering) * tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: Clarify comment on x2apic mode hv_balloon: disable warning when floor reached
2020-10-19hv_balloon: disable warning when floor reachedOlaf Hering
It is not an error if the host requests to balloon down, but the VM refuses to do so. Without this change a warning is logged in dmesg every five minutes. Fixes: b3bb97b8a49f3 ("Drivers: hv: balloon: Add logging for dynamic memory operations") Signed-off-by: Olaf Hering <olaf@aepfle.de> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20201008071216.16554-1-olaf@aepfle.de Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-10-16hv_balloon: try to merge system ram resourcesDavid Hildenbrand
Let's try to merge system ram resources we add, to minimize the number of resources in /proc/iomem. We don't care about the boundaries of individual chunks we added. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Liu <wei.liu@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Grall <julien@xen.org> Cc: Kees Cook <keescook@chromium.org> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Link: https://lkml.kernel.org/r/20200911103459.10306-9-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16mm/memory_hotplug: prepare passing flags to add_memory() and friendsDavid Hildenbrand
We soon want to pass flags, e.g., to mark added System RAM resources. mergeable. Prepare for that. This patch is based on a similar patch by Oscar Salvador: https://lkml.kernel.org/r/20190625075227.15193-3-osalvador@suse.de Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Juergen Gross <jgross@suse.com> # Xen related part Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Wei Liu <wei.liu@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Julien Grall <julien@xen.org> Cc: Kees Cook <keescook@chromium.org> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Yang <richardw.yang@linux.intel.com> Link: https://lkml.kernel.org/r/20200911103459.10306-5-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07hv_balloon: don't check for memhp_auto_online manuallyDavid Hildenbrand
We get the MEM_ONLINE notifier call if memory is added right from the kernel via add_memory() or later from user space. Let's get rid of the "ha_waiting" flag - the wait event has an inbuilt mechanism (->done) for that. Initialize the wait event only once and reinitialize before adding memory. Unconditionally call complete() and wait_for_completion_timeout(). If there are no waiters, complete() will only increment ->done - which will be reset by reinit_completion(). If complete() has already been called, wait_for_completion_timeout() will not wait. There is still the chance for a small race between concurrent reinit_completion() and complete(). If complete() wins, we would not wait - which is tolerable (and the race exists in current code as well). Note: We only wait for "some" memory to get onlined, which seems to be good enough for now. [akpm@linux-foundation.org: register_memory_notifier() after init_completion(), per David] Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Yumei Huang <yuhuang@redhat.com> Link: http://lkml.kernel.org/r/20200317104942.11178-6-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-25hv_balloon: Balloon up according to request page numberTianyu Lan
Current code has assumption that balloon request memory size aligns with 2MB. But actually Hyper-V doesn't guarantee such alignment. When balloon driver receives non-aligned balloon request, it produces warning and balloon up more memory than requested in order to keep 2MB alignment. Remove the warning and balloon up memory according to actual requested memory size. Fixes: f6712238471a ("hv: hv_balloon: avoid memory leak on alloc_error of 2MB memory block") Cc: stable@vger.kernel.org Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-01Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: "Incoming: - a small number of updates to scripts/, ocfs2 and fs/buffer.c - most of MM I still have quite a lot of material (mostly not MM) staged after linux-next due to -next dependencies. I'll send those across next week as the preprequisites get merged up" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (135 commits) mm/page_io.c: annotate refault stalls from swap_readpage mm/Kconfig: fix trivial help text punctuation mm/Kconfig: fix indentation mm/memory_hotplug.c: remove __online_page_set_limits() mm: fix typos in comments when calling __SetPageUptodate() mm: fix struct member name in function comments mm/shmem.c: cast the type of unmap_start to u64 mm: shmem: use proper gfp flags for shmem_writepage() mm/shmem.c: make array 'values' static const, makes object smaller userfaultfd: require CAP_SYS_PTRACE for UFFD_FEATURE_EVENT_FORK fs/userfaultfd.c: wp: clear VM_UFFD_MISSING or VM_UFFD_WP during userfaultfd_register() userfaultfd: wrap the common dst_vma check into an inlined function userfaultfd: remove unnecessary WARN_ON() in __mcopy_atomic_hugetlb() userfaultfd: use vma_pagesize for all huge page size calculation mm/madvise.c: use PAGE_ALIGN[ED] for range checking mm/madvise.c: replace with page_size() in madvise_inject_error() mm/mmap.c: make vma_merge() comment more easy to understand mm/hwpoison-inject: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops autonuma: reduce cache footprint when scanning page tables autonuma: fix watermark checking in migrate_balanced_pgdat() ...
2019-12-01mm/memory_hotplug.c: remove __online_page_set_limits()Souptick Joarder
__online_page_set_limits() is a dummy function - remove it and all callers. Link: http://lkml.kernel.org/r/8e1bc9d3b492f6bde16e95ebc1dee11d6aefabd7.1567889743.git.jrdr.linux@gmail.com Link: http://lkml.kernel.org/r/854db2cf8145d9635249c95584d9a91fd774a229.1567889743.git.jrdr.linux@gmail.com Link: http://lkml.kernel.org/r/9afe6c5a18158f3884a6b302ac2c772f3da49ccc.1567889743.git.jrdr.linux@gmail.com Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01hv_balloon: use generic_online_page()David Hildenbrand
Let's use the generic onlining function - which will now also take care of calling kernel_map_pages(). Link: http://lkml.kernel.org/r/20190909114830.662-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Sasha Levin <sashal@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Qian Cai <cai@lca.pw> Cc: Wei Yang <richard.weiyang@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-21hv_balloon: Add the support of hibernationDexuan Cui
When hibernation is enabled, we must ignore the balloon up/down and hot-add requests from the host, if any. Signed-off-by: Dexuan Cui <decui@microsoft.com> Acked-by: David Hildenbrand <david@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-21Drivers: hv: balloon: Remove dependencies on guest page sizeHimadri Pandya
Hyper-V assumes page size to be 4K. This might not be the case for ARM64 architecture. Hence use hyper-v specific page size and page shift definitions to avoid conflicts between different host and guest page sizes on ARM64. Also, remove some old and incorrect comments and redefine ballooning granularities to handle larger page sizes correctly. Signed-off-by: Himadri Pandya <himadri18.07@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-30hv_balloon: Reorganize the probe functionDexuan Cui
Move the code that negotiates with the host to a new function balloon_connect_vsp() and improve the error handling. This makes the code more readable and paves the way for the support of hibernation in future. Makes no real logic change here. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-30hv_balloon: Use a static page for the balloon_up send bufferDexuan Cui
It's unnecessary to dynamically allocate the buffer. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 280Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose good title or non infringement see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 9 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141900.459653302@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-05hv_balloon: mark inflated pages PG_offlineDavid Hildenbrand
Mark inflated and never onlined pages PG_offline, to tell the world that the content is stale and should not be dumped. Link: http://lkml.kernel.org/r/20181119101616.8901-6-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Pankaj gupta <pagupta@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Kairui Song <kasong@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Hansen <chansen3@cisco.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Freche <jfreche@vmware.com> Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Lianbo Jiang <lijiang@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Nadav Amit <namit@vmware.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xavier Deguillard <xdeguillard@vmware.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05mm/page_alloc.c: memory hotplug: free pages as higher orderArun KS
When freeing pages are done with higher order, time spent on coalescing pages by buddy allocator can be reduced. With section size of 256MB, hot add latency of a single section shows improvement from 50-60 ms to less than 1 ms, hence improving the hot add latency by 60 times. Modify external providers of online callback to align with the change. [arunks@codeaurora.org: v11] Link: http://lkml.kernel.org/r/1547792588-18032-1-git-send-email-arunks@codeaurora.org [akpm@linux-foundation.org: remove unused local, per Arun] [akpm@linux-foundation.org: avoid return of void-returning __free_pages_core(), per Oscar] [akpm@linux-foundation.org: fix it for mm-convert-totalram_pages-and-totalhigh_pages-variables-to-atomic.patch] [arunks@codeaurora.org: v8] Link: http://lkml.kernel.org/r/1547032395-24582-1-git-send-email-arunks@codeaurora.org [arunks@codeaurora.org: v9] Link: http://lkml.kernel.org/r/1547098543-26452-1-git-send-email-arunks@codeaurora.org Link: http://lkml.kernel.org/r/1538727006-5727-1-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mathieu Malaterre <malat@debian.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Souptick Joarder <jrdr.linux@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Srivatsa Vaddagiri <vatsa@codeaurora.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-09hv_balloon: avoid touching uninitialized struct page during tail onliningVitaly Kuznetsov
Hyper-V memory hotplug protocol has 2M granularity and in Linux x86 we use 128M. To deal with it we implement partial section onlining by registering custom page onlining callback (hv_online_page()). Later, when more memory arrives we try to online the 'tail' (see hv_bring_pgs_online()). It was found that in some cases this 'tail' onlining causes issues: BUG: Bad page state in process kworker/0:2 pfn:109e3a page:ffffe08344278e80 count:0 mapcount:1 mapping:0000000000000000 index:0x0 flags: 0xfffff80000000() raw: 000fffff80000000 dead000000000100 dead000000000200 0000000000000000 raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 page dumped because: nonzero mapcount ... Workqueue: events hot_add_req [hv_balloon] Call Trace: dump_stack+0x5c/0x80 bad_page.cold.112+0x7f/0xb2 free_pcppages_bulk+0x4b8/0x690 free_unref_page+0x54/0x70 hv_page_online_one+0x5c/0x80 [hv_balloon] hot_add_req.cold.24+0x182/0x835 [hv_balloon] ... Turns out that we now have deferred struct page initialization for memory hotplug so e.g. memory_block_action() in drivers/base/memory.c does pages_correctly_probed() check and in that check it avoids inspecting struct pages and checks sections instead. But in Hyper-V balloon driver we do PageReserved(pfn_to_page()) check and this is now wrong. Switch to checking online_section_nr() instead. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: stable@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-28mm: convert totalram_pages and totalhigh_pages variables to atomicArun KS
totalram_pages and totalhigh_pages are made static inline function. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes better to remove the lock and convert variables to atomic, with preventing poteintial store-to-read tearing as a bonus. [akpm@linux-foundation.org: coding style fixes] Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Suggested-by: Michal Hocko <mhocko@suse.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28mm: reference totalram_pages and managed_pages once per functionArun KS
Patch series "mm: convert totalram_pages, totalhigh_pages and managed pages to atomic", v5. This series converts totalram_pages, totalhigh_pages and zone->managed_pages to atomic variables. totalram_pages, zone->managed_pages and totalhigh_pages updates are protected by managed_page_count_lock, but readers never care about it. Convert these variables to atomic to avoid readers potentially seeing a store tear. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better to remove the lock and convert variables to atomic. With the change, preventing poteintial store-to-read tearing comes as a bonus. This patch (of 4): This is in preparation to a later patch which converts totalram_pages and zone->managed_pages to atomic variables. Please note that re-reading the value might lead to a different value and as such it could lead to unexpected behavior. There are no known bugs as a result of the current code but it is better to prevent from them in principle. Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-15hv_balloon: Replace spin_is_locked() with lockdepLance Roy
lockdep_assert_held() is better suited to checking locking requirements, since it won't get confused when someone else holds the lock. This is also a step towards possibly removing spin_is_locked(). Signed-off-by: Lance Roy <ldr709@gmail.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03use the new async probing feature for the hyperv driversArjan van de Ven
Recent kernels support asynchronous probing; most hyperv drivers can be probed async easily so set the required flag for this. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06hv_balloon: trace post_statusVitaly Kuznetsov
Hyper-V balloon driver makes non-trivial calculations to convert Linux's representation of free/used memory to what Hyper-V host expects to see. Add a tracepoint to see what's being sent and where the data comes from. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06hv_balloon: fix bugs in num_pages_onlined accountingVitaly Kuznetsov
Our num_pages_onlined accounting is buggy: 1) In case we're offlining a memory block which was present at boot (e.g. when there was no hotplug at all) we subtract 32k from 0 and as num_pages_onlined is unsigned get a very big positive number. 2) Commit 6df8d9aaf3af ("Drivers: hv: balloon: Correctly update onlined page count") made num_pages_onlined counter accurate on onlining but totally incorrect on offlining for partly populated regions: no matter how many pages were onlined and what was actually added to num_pages_onlined counter we always subtract the full region (32k) so again, num_pages_onlined can wrap around zero. By onlining/offlining the same partly populated region multiple times we can make the situation worse. Solve these issues by doing accurate accounting on offlining: walk HAS list, check for covered range and gaps. Fixes: 6df8d9aaf3af ("Drivers: hv: balloon: Correctly update onlined page count") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06hv_balloon: simplify hv_online_page()/hv_page_online_one()Vitaly Kuznetsov
Instead of doing pfn_to_page() and continuosly casting page to unsigned long just cache the pfn of the page with page_to_pfn(). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06hv_balloon: fix printk loglevelVitaly Kuznetsov
We have a mix of different ideas of which loglevel should be used. Unify on the following: - pr_info() for normal operation - pr_warn() for 'strange' host behavior - pr_err() for all errors. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16Drivers: hv: balloon: Initialize last_post_time on startupAlex Ng
When left uninitialized, this sometimes fails the following check in post_status(): if (!time_after(now, (last_post_time + HZ))) { return; } This causes unnecessary delays in reporting memory pressure to host after booting up. Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16Drivers: hv: balloon: Show the max dynamic memory assignedAlex Ng
Previously we were only showing max number of pages. We should make it more clear that this value is the max amount of dynamic memory that the Hyper-V host is willing to assign to this guest. Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16Drivers: hv: balloon: Correctly update onlined page countAlex Ng
Previously, num_pages_onlined was updated using value from memory online notifier. This is incorrect because they assume that all hot-added pages are online, even though we only online the amount that's backed by the host. We should update num_pages_onlined only when the balloon driver marks a page as online. Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17vmbus: remove useless return'sStephen Hemminger
No need for empty return at end of void function Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>