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
Following the recommendation in Documentation/memory-barriers.txt for
virtual machine guests.
Fixes: 8b6a877c060ed ("Drivers: hv: vmbus: Replace the per-CPU channel lists with a global array of channels")
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Link: https://lore.kernel.org/r/20220328154457.100872-1-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
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>
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>
When reading a packet from a host-to-guest ring buffer, there is no memory barrier between reading the write index (to see if there is a packet to read) and reading the contents of the packet. The Hyper-V host uses store-release when updating the write index to ensure that writes of the packet data are completed first. On the guest side, the processor can reorder and read the packet data before the write index, and sometimes get stale packet data. Getting such stale packet data has been observed in a reproducible case in a VM on ARM64. Fix this by using virt_load_acquire() to read the write index, ensuring that reads of the packet data cannot be reordered before it. Preventing such reordering is logically correct, and with this change, getting stale data can no longer be reproduced. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/1648394710-33480-1-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
VMbus synthetic devices are not represented in the ACPI DSDT -- only the top level VMbus device is represented. As a result, on ARM64 coherence information in the _CCA method is not specified for synthetic devices, so they default to not hardware coherent. Drivers for some of these synthetic devices have been recently updated to use the standard DMA APIs, and they are incurring extra overhead of unneeded software coherence management. Fix this by propagating coherence information from the VMbus node in ACPI to the individual synthetic devices. There's no effect on x86/x64 where devices are always hardware coherent. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/1648138492-2191-2-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
The vmbus driver relies on the panic notifier infrastructure to perform
some operations when a panic event is detected. Since vmbus can be built
as module, it is required that the driver handles both registering and
unregistering such panic notifier callback.
After commit 74347a99e73a ("x86/Hyper-V: Unload vmbus channel in hv panic callback")
though, the panic notifier registration is done unconditionally in the module
initialization routine whereas the unregistering procedure is conditionally
guarded and executes only if HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE capability
is set.
This patch fixes that by unconditionally unregistering the panic notifier
in the module's exit routine as well.
Fixes: 74347a99e73a ("x86/Hyper-V: Unload vmbus channel in hv panic callback")
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20220315203535.682306-1-gpiccoli@igalia.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Initialize the device's dma_{mask,parms} pointers and the device's
dma_mask value before invoking device_register(). Address the
following trace with 5.17-rc7:
[ 49.646839] WARNING: CPU: 0 PID: 189 at include/linux/dma-mapping.h:543
netvsc_probe+0x37a/0x3a0 [hv_netvsc]
[ 49.646928] Call Trace:
[ 49.646930] <TASK>
[ 49.646935] vmbus_probe+0x40/0x60 [hv_vmbus]
[ 49.646942] really_probe+0x1ce/0x3b0
[ 49.646948] __driver_probe_device+0x109/0x180
[ 49.646952] driver_probe_device+0x23/0xa0
[ 49.646955] __device_attach_driver+0x76/0xe0
[ 49.646958] ? driver_allows_async_probing+0x50/0x50
[ 49.646961] bus_for_each_drv+0x84/0xd0
[ 49.646964] __device_attach+0xed/0x170
[ 49.646967] device_initial_probe+0x13/0x20
[ 49.646970] bus_probe_device+0x8f/0xa0
[ 49.646973] device_add+0x41a/0x8e0
[ 49.646975] ? hrtimer_init+0x28/0x80
[ 49.646981] device_register+0x1b/0x20
[ 49.646983] vmbus_device_register+0x5e/0xf0 [hv_vmbus]
[ 49.646991] vmbus_add_channel_work+0x12d/0x190 [hv_vmbus]
[ 49.646999] process_one_work+0x21d/0x3f0
[ 49.647002] worker_thread+0x4a/0x3b0
[ 49.647005] ? process_one_work+0x3f0/0x3f0
[ 49.647007] kthread+0xff/0x130
[ 49.647011] ? kthread_complete_and_exit+0x20/0x20
[ 49.647015] ret_from_fork+0x22/0x30
[ 49.647020] </TASK>
[ 49.647021] ---[ end trace 0000000000000000 ]---
Fixes: 743b237c3a7b0 ("scsi: storvsc: Add Isolation VM support for storvsc driver")
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20220315141053.3223-1-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
hv_panic_page might contain guest-sensitive information, do not dump it
over to Hyper-V by default in isolated guests.
While at it, update some comments in hyperv_{panic,die}_event().
Reported-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Link: https://lore.kernel.org/r/20220301141135.2232-1-parri.andrea@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Pull hyperv updates from Wei Liu: "Minor patches from various people" * tag 'hyperv-next-signed-20220322' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: Output host build info as normal Windows version number hv_balloon: rate-limit "Unhandled message" warning drivers: hv: log when enabling crash_kexec_post_notifiers hv_utils: Add comment about max VMbus packet size in VSS driver Drivers: hv: Compare cpumasks and not their weights in init_vp_index() Drivers: hv: Rename 'alloced' to 'allocated' Drivers: hv: vmbus: Use struct_size() helper in kmalloc()