aboutsummaryrefslogtreecommitdiff
path: root/include/xen
AgeCommit message (Collapse)Author
2023-12-08xen: simplify evtchn_do_upcall() call mazeJuergen Gross
[ Upstream commit 37510dd566bdbff31a769cde2fa6654bccdb8b24 ] There are several functions involved for performing the functionality of evtchn_do_upcall(): - __xen_evtchn_do_upcall() doing the real work - xen_hvm_evtchn_do_upcall() just being a wrapper for __xen_evtchn_do_upcall(), exposed for external callers - xen_evtchn_do_upcall() calling __xen_evtchn_do_upcall(), too, but without any user Simplify this maze by: - removing the unused xen_evtchn_do_upcall() - removing xen_hvm_evtchn_do_upcall() as the only left caller of __xen_evtchn_do_upcall(), while renaming __xen_evtchn_do_upcall() to xen_evtchn_do_upcall() Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Juergen Gross <jgross@suse.com> Stable-dep-of: db2832309a82 ("x86/xen: fix percpu vcpu_info allocation") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08xen: Allow platform PCI interrupt to be sharedDavid Woodhouse
[ Upstream commit 3e8cd711c3da6c3d724076048038cd666bdbb2b5 ] When we don't use the per-CPU vector callback, we ask Xen to deliver event channel interrupts as INTx on the PCI platform device. As such, it can be shared with INTx on other PCI devices. Set IRQF_SHARED, and make it return IRQ_HANDLED or IRQ_NONE according to whether the evtchn_upcall_pending flag was actually set. Now I can share the interrupt: 11: 82 0 IO-APIC 11-fasteoi xen-platform-pci, ens4 Drop the IRQF_TRIGGER_RISING. It has no effect when the IRQ is shared, and besides, the only effect it was having even beforehand was to trigger a debug message in both I/OAPIC and legacy PIC cases: [ 0.915441] genirq: No set_type function for IRQ 11 (IO-APIC) [ 0.951939] genirq: No set_type function for IRQ 11 (XT-PIC) Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/f9a29a68d05668a3636dd09acd94d970269eaec6.camel@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com> Stable-dep-of: db2832309a82 ("x86/xen: fix percpu vcpu_info allocation") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11ACPI: processor: Fix evaluating _PDC method when running as Xen dom0Roger Pau Monne
[ Upstream commit 073828e954459b883f23e53999d31e4c55ab9654 ] In ACPI systems, the OS can direct power management, as opposed to the firmware. This OS-directed Power Management is called OSPM. Part of telling the firmware that the OS going to direct power management is making ACPI "_PDC" (Processor Driver Capabilities) calls. These _PDC methods must be evaluated for every processor object. If these _PDC calls are not completed for every processor it can lead to inconsistency and later failures in things like the CPU frequency driver. In a Xen system, the dom0 kernel is responsible for system-wide power management. The dom0 kernel is in charge of OSPM. However, the number of CPUs available to dom0 can be different than the number of CPUs physically present on the system. This leads to a problem: the dom0 kernel needs to evaluate _PDC for all the processors, but it can't always see them. In dom0 kernels, ignore the existing ACPI method for determining if a processor is physically present because it might not be accurate. Instead, ask the hypervisor for this information. Fix this by introducing a custom function to use when running as Xen dom0 in order to check whether a processor object matches a CPU that's online. Such checking is done using the existing information fetched by the Xen pCPU subsystem, extending it to also store the ACPI ID. This ensures that _PDC method gets evaluated for all physically online CPUs, regardless of the number of CPUs made available to dom0. Fixes: 5d554a7bb064 ("ACPI: processor: add internal processor_physically_present()") Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-06x86/PVH: obtain VGA console info in Dom0Jan Beulich
[ Upstream commit 934ef33ee75c3846f605f18b65048acd147e3918 ] A new platform-op was added to Xen to allow obtaining the same VGA console information PV Dom0 is handed. Invoke the new function and have the output data processed by xen_init_vga(). Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/8f315e92-7bda-c124-71cc-478ab9c5e610@suse.com Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-10xen/virtio: enable grant based virtio on x86Juergen Gross
Use an x86-specific virtio_check_mem_acc_cb() for Xen in order to setup the correct DMA ops. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # common code Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2022-08-12x86/xen: Add support for HVMOP_set_evtchn_upcall_vectorJane Malalane
Implement support for the HVMOP_set_evtchn_upcall_vector hypercall in order to set the per-vCPU event channel vector callback on Linux and use it in preference of HVM_PARAM_CALLBACK_IRQ. If the per-VCPU vector setup is successful on BSP, use this method for the APs. If not, fallback to the global vector-type callback. Also register callback_irq at per-vCPU event channel setup to trick toolstack to think the domain is enlightened. Suggested-by: "Roger Pau Monné" <roger.pau@citrix.com> Signed-off-by: Jane Malalane <jane.malalane@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220729070416.23306-1-jane.malalane@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-08-01xen: don't require virtio with grants for non-PV guestsJuergen Gross
Commit fa1f57421e0b ("xen/virtio: Enable restricted memory access using Xen grant mappings") introduced a new requirement for using virtio devices: the backend now needs to support the VIRTIO_F_ACCESS_PLATFORM feature. This is an undue requirement for non-PV guests, as those can be operated with existing backends without any problem, as long as those backends are running in dom0. Per default allow virtio devices without grant support for non-PV guests. On Arm require VIRTIO_F_ACCESS_PLATFORM for devices having been listed in the device tree to use grants. Add a new config item to always force use of grants for virtio. Fixes: fa1f57421e0b ("xen/virtio: Enable restricted memory access using Xen grant mappings") Reported-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 guest using Xen Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220622063838.8854-4-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-08-01virtio: replace restricted mem access flag with callbackJuergen Gross
Instead of having a global flag to require restricted memory access for all virtio devices, introduce a callback which can select that requirement on a per-device basis. For convenience add a common function returning always true, which can be used for use cases like SEV. Per default use a callback always returning false. As the callback needs to be set in early init code already, add a virtio anchor which is builtin in case virtio is enabled. Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 guest using Xen Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220622063838.8854-2-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06arm/xen: Assign xen-grant DMA ops for xen-grant DMA devicesOleksandr Tyshchenko
By assigning xen-grant DMA ops we will restrict memory access for passed device using Xen grant mappings. This is needed for using any virtualized device (e.g. virtio) in Xen guests in a safe manner. Please note, for the virtio devices the XEN_VIRTIO config should be enabled (it forces ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS). Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/1654197833-25362-9-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06xen/grant-dma-ops: Retrieve the ID of backend's domain for DT devicesOleksandr Tyshchenko
Use the presence of "iommus" property pointed to the IOMMU node with recently introduced "xen,grant-dma" compatible as a clear indicator of enabling Xen grant mappings scheme for that device and read the ID of Xen domain where the corresponding backend is running. The domid (domain ID) is used as an argument to the Xen grant mapping APIs. To avoid the deferred probe timeout which takes place after reusing generic IOMMU device tree bindings (because the IOMMU device never becomes available) enable recently introduced stub IOMMU driver by selecting XEN_GRANT_DMA_IOMMU. Also introduce xen_is_grant_dma_device() to check whether xen-grant DMA ops need to be set for a passed device. Remove the hardcoded domid 0 in xen_grant_setup_dma_ops(). Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/1654197833-25362-8-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06xen/virtio: Enable restricted memory access using Xen grant mappingsJuergen Gross
In order to support virtio in Xen guests add a config option XEN_VIRTIO enabling the user to specify whether in all Xen guests virtio should be able to access memory via Xen grant mappings only on the host side. Also set PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS feature from the guest initialization code on Arm and x86 if CONFIG_XEN_VIRTIO is enabled. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/1654197833-25362-5-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06xen/grant-dma-ops: Add option to restrict memory access under XenJuergen Gross
Introduce Xen grant DMA-mapping layer which contains special DMA-mapping routines for providing grant references as DMA addresses to be used by frontends (e.g. virtio) in Xen guests. Add the needed functionality by providing a special set of DMA ops handling the needed grant operations for the I/O pages. The subsequent commit will introduce the use case for xen-grant DMA ops layer to enable using virtio devices in Xen guests in a safe manner. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/1654197833-25362-4-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06xen/grants: support allocating consecutive grantsJuergen Gross
For support of virtio via grant mappings in rare cases larger mappings using consecutive grants are needed. Support those by adding a bitmap of free grants. As consecutive grants will be needed only in very rare cases (e.g. when configuring a virtio device with a multi-page ring), optimize for the normal case of non-consecutive allocations. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/1654197833-25362-3-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06arm/xen: Introduce xen_setup_dma_ops()Oleksandr Tyshchenko
This patch introduces new helper and places it in new header. The helper's purpose is to assign any Xen specific DMA ops in a single place. For now, we deal with xen-swiotlb DMA ops only. The one of the subsequent commits in current series will add xen-grant DMA ops case. Also re-use the xen_swiotlb_detect() check on Arm32. Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> [For arm64] Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/1654197833-25362-2-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-04Merge tag 'for-linus-5.19-rc1b-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: "Two cleanup patches for Xen related code and (more important) an update of MAINTAINERS for Xen, as Boris Ostrovsky decided to step down" * tag 'for-linus-5.19-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: replace xen_remap() with memremap() MAINTAINERS: Update Xen maintainership xen: switch gnttab_end_foreign_access() to take a struct page pointer
2022-06-01xen: replace xen_remap() with memremap()Juergen Gross
xen_remap() is used to establish mappings for frames not under direct control of the kernel: for Xenstore and console ring pages, and for grant pages of non-PV guests. Today xen_remap() is defined to use ioremap() on x86 (doing uncached mappings), and ioremap_cache() on Arm (doing cached mappings). Uncached mappings for those use cases are bad for performance, so they should be avoided if possible. As all use cases of xen_remap() don't require uncached mappings (the mapped area is always physical RAM), a mapping using the standard WB cache mode is fine. As sparse is flagging some of the xen_remap() use cases to be not appropriate for iomem(), as the result is not annotated with the __iomem modifier, eliminate xen_remap() completely and replace all use cases with memremap() specifying the MEMREMAP_WB caching mode. xen_unmap() can be replaced with memunmap(). Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220530082634.6339-1-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-27xen: switch gnttab_end_foreign_access() to take a struct page pointerJuergen Gross
Instead of a virtual kernel address use a pointer of the associated struct page as second parameter of gnttab_end_foreign_access(). Most users have that pointer available already and are creating the virtual address from it, risking problems in case the memory is located in highmem. gnttab_end_foreign_access() itself won't need to get the struct page from the address again. Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-25Merge tag 'dma-mapping-5.19-2022-05-25' of ↵Linus Torvalds
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - don't over-decrypt memory (Robin Murphy) - takes min align mask into account for the swiotlb max mapping size (Tianyu Lan) - use GFP_ATOMIC in dma-debug (Mikulas Patocka) - fix DMA_ATTR_NO_KERNEL_MAPPING on xen/arm (me) - don't fail on highmem CMA pages in dma_direct_alloc_pages (me) - cleanup swiotlb initialization and share more code with swiotlb-xen (me, Stefano Stabellini) * tag 'dma-mapping-5.19-2022-05-25' of git://git.infradead.org/users/hch/dma-mapping: (23 commits) dma-direct: don't over-decrypt memory swiotlb: max mapping size takes min align mask into account swiotlb: use the right nslabs-derived sizes in swiotlb_init_late swiotlb: use the right nslabs value in swiotlb_init_remap swiotlb: don't panic when the swiotlb buffer can't be allocated dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMIC dma-direct: don't fail on highmem CMA pages in dma_direct_alloc_pages swiotlb-xen: fix DMA_ATTR_NO_KERNEL_MAPPING on arm x86: remove cruft from <asm/dma-mapping.h> swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl swiotlb: merge swiotlb-xen initialization into swiotlb swiotlb: provide swiotlb_init variants that remap the buffer swiotlb: pass a gfp_mask argument to swiotlb_init_late swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction swiotlb: make the swiotlb_init interface more useful x86: centralize setting SWIOTLB_FORCE when guest memory encryption is enabled x86: remove the IOMMU table infrastructure MIPS/octeon: use swiotlb_init instead of open coding it arm/xen: don't check for xen_initial_domain() in xen_create_contiguous_region swiotlb: rename swiotlb_late_init_with_default_size ...
2022-05-19xen: sync xs_wire.h header with upstream xenStefano Stabellini
Sync the xs_wire.h header file in Linux with the one in Xen. Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220513211938.719341-1-sstabellini@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-19xen/xenbus: eliminate xenbus_grant_ring()Juergen Gross
There is no external user of xenbus_grant_ring() left, so merge it into the only caller xenbus_setup_ring(). Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-19xen/xenbus: add xenbus_setup_ring() service functionJuergen Gross
Most PV device frontends share very similar code for setting up shared ring buffers: - allocate page(s) - init the ring admin data - give the backend access to the ring via grants Tearing down the ring requires similar actions in all frontends again: - remove grants - free the page(s) Provide service functions xenbus_setup_ring() and xenbus_teardown_ring() for that purpose. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-19xen: update ring.hJuergen Gross
Update include/xen/interface/io/ring.h to its newest version. Switch the two improper use cases of RING_HAS_UNCONSUMED_RESPONSES() to XEN_RING_NR_UNCONSUMED_RESPONSES() in order to avoid the nasty XEN_RING_HAS_UNCONSUMED_IS_BOOL #define. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-19xen: update grant_table.hJuergen Gross
Update include/xen/interface/grant_table.h to its newest version. This allows to drop some private definitions in grant-table.c and include/xen/grant_table.h. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-19xen: update vscsiif.hJuergen Gross
Update include/xen/interface/io/vscsiif.h to its newest version. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220428075323.12853-2-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-11swiotlb-xen: fix DMA_ATTR_NO_KERNEL_MAPPING on armChristoph Hellwig
swiotlb-xen uses very different ways to allocate coherent memory on x86 vs arm. On the former it allocates memory from the page allocator, while on the later it reuses the dma-direct allocator the handles the complexities of non-coherent DMA on arm platforms. Unfortunately the complexities of trying to deal with the two cases in the swiotlb-xen.c code lead to a bug in the handling of DMA_ATTR_NO_KERNEL_MAPPING on arm. With the DMA_ATTR_NO_KERNEL_MAPPING flag the coherent memory allocator does not actually allocate coherent memory, but just a DMA handle for some memory that is DMA addressable by the device, but which does not have to have a kernel mapping. Thus dereferencing the return value will lead to kernel crashed and memory corruption. Fix this by using the dma-direct allocator directly for arm, which works perfectly fine because on arm swiotlb-xen is only used when the domain is 1:1 mapped, and then simplifying the remaining code to only cater for the x86 case with DMA coherent device. Reported-by: Rahul Singh <Rahul.Singh@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Rahul Singh <rahul.singh@arm.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Tested-by: Rahul Singh <rahul.singh@arm.com>
2022-04-18swiotlb: merge swiotlb-xen initialization into swiotlbChristoph Hellwig
Reuse the generic swiotlb initialization for xen-swiotlb. For ARM/ARM64 this works trivially, while for x86 xen_swiotlb_fixup needs to be passed as the remap argument to swiotlb_init_remap/swiotlb_init_late. Note that the lower bound of the swiotlb size is changed to the smaller IO_TLB_MIN_SLABS based value with this patch, but that is fine as the 2MB value used in Xen before was just an optimization and is not the hard lower bound. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-03-15xen/grant-table: remove readonly parameter from functionsJuergen Gross
The gnttab_end_foreign_access() family of functions is taking a "readonly" parameter, which isn't used. Remove it from the function parameters. Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20220311103429.12845-3-jgross@suse.com Reviewed-by: Jan Beulich <jbeulich@suse.com> Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-03-15xen/grant-table: remove gnttab_*transfer*() functionsJuergen Gross
All grant table operations related to the "transfer" functionality are unused currently. There have been users in the old days of the "Xen-o-Linux" kernel, but those didn't make it upstream. So remove the "transfer" related functions. Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20220311103429.12845-2-jgross@suse.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-03-07xen/gnttab: fix gnttab_end_foreign_access() without page specifiedJuergen Gross
gnttab_end_foreign_access() is used to free a grant reference and optionally to free the associated page. In case the grant is still in use by the other side processing is being deferred. This leads to a problem in case no page to be freed is specified by the caller: the caller doesn't know that the page is still mapped by the other side and thus should not be used for other purposes. The correct way to handle this situation is to take an additional reference to the granted page in case handling is being deferred and to drop that reference when the grant reference could be freed finally. This requires that there are no users of gnttab_end_foreign_access() left directly repurposing the granted page after the call, as this might result in clobbered data or information leaks via the not yet freed grant reference. This is part of CVE-2022-23041 / XSA-396. Reported-by: Simon Gaiser <simon@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> --- V4: - expand comment in header V5: - get page ref in case of kmalloc() failure, too
2022-03-07xen: remove gnttab_query_foreign_access()Juergen Gross
Remove gnttab_query_foreign_access(), as it is unused and unsafe to use. All previous use cases assumed a grant would not be in use after gnttab_query_foreign_access() returned 0. This information is useless in best case, as it only refers to a situation in the past, which could have changed already. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-07xen/grant-table: add gnttab_try_end_foreign_access()Juergen Gross
Add a new grant table function gnttab_try_end_foreign_access(), which will remove and free a grant if it is not in use. Its main use case is to either free a grant if it is no longer in use, or to take some other action if it is still in use. This other action can be an error exit, or (e.g. in the case of blkfront persistent grant feature) some special handling. This is CVE-2022-23036, CVE-2022-23038 / part of XSA-396. Reported-by: Demi Marie Obenour <demi@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> --- V2: - new patch V4: - add comments to header (Jan Beulich)
2022-02-03xen: xenbus_dev.h: delete incorrect file nameRandy Dunlap
It is better/preferred not to include file names in source files because (a) they are not needed and (b) they can be incorrect, so just delete this incorrect file name. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lore.kernel.org/r/20220130191705.24971-1-rdunlap@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com>
2022-01-12Merge tag 'for-linus-5.17-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - a fix for the Xen gntdev driver - a fix for running as Xen dom0 booted via EFI and the EFI framebuffer being located above 4GB - a series for support of mapping other guest's memory by using zone device when running as Xen guest on Arm * tag 'for-linus-5.17-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: dt-bindings: xen: Clarify "reg" purpose arm/xen: Read extended regions from DT and init Xen resource xen/unpopulated-alloc: Add mechanism to use Xen resource xen/balloon: Bring alloc(free)_xenballooned_pages helpers back arm/xen: Switch to use gnttab_setup_auto_xlat_frames() for DT xen/unpopulated-alloc: Drop check for virt_addr_valid() in fill_list() xen/x86: obtain upper 32 bits of video frame buffer address for Dom0 xen/gntdev: fix unmap notification order
2022-01-06xen/unpopulated-alloc: Add mechanism to use Xen resourceOleksandr Tyshchenko
The main reason of this change is that unpopulated-alloc code cannot be used in its current form on Arm, but there is a desire to reuse it to avoid wasting real RAM pages for the grant/foreign mappings. The problem is that system "iomem_resource" is used for the address space allocation, but the really unallocated space can't be figured out precisely by the domain on Arm without hypervisor involvement. For example, not all device I/O regions are known by the time domain starts creating grant/foreign mappings. And following the advise from "iomem_resource" we might end up reusing these regions by a mistake. So, the hypervisor which maintains the P2M for the domain is in the best position to provide unused regions of guest physical address space which could be safely used to create grant/foreign mappings. Introduce new helper arch_xen_unpopulated_init() which purpose is to create specific Xen resource based on the memory regions provided by the hypervisor to be used as unused space for Xen scratch pages. If arch doesn't define arch_xen_unpopulated_init() the default "iomem_resource" will be used. Update the arguments list of allocate_resource() in fill_list() to always allocate a region from the hotpluggable range (maximum possible addressable physical memory range for which the linear mapping could be created). If arch doesn't define arch_get_mappable_range() the default range (0,-1) will be used. The behaviour on x86 won't be changed by current patch as both arch_xen_unpopulated_init() and arch_get_mappable_range() are not implemented for it. Also fallback to allocate xenballooned pages (balloon out RAM pages) if we do not have any suitable resource to work with (target_resource is invalid) and as the result we won't be able to provide unpopulated pages on a request. Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/1639080336-26573-5-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-01-06xen/balloon: Bring alloc(free)_xenballooned_pages helpers backOleksandr Tyshchenko
This patch rolls back some of the changes introduced by commit 121f2faca2c0a "xen/balloon: rename alloc/free_xenballooned_pages" in order to make possible to still allocate xenballooned pages if CONFIG_XEN_UNPOPULATED_ALLOC is enabled. On Arm the unpopulated pages will be allocated on top of extended regions provided by Xen via device-tree (the subsequent patches will add required bits to support unpopulated-alloc feature on Arm). The problem is that extended regions feature has been introduced into Xen quite recently (during 4.16 release cycle). So this effectively means that Linux must only use unpopulated-alloc on Arm if it is running on "new Xen" which advertises these regions. But, it will only be known after parsing the "hypervisor" node at boot time, so before doing that we cannot assume anything. In order to keep working if CONFIG_XEN_UNPOPULATED_ALLOC is enabled and the extended regions are not advertised (Linux is running on "old Xen", etc) we need the fallback to alloc_xenballooned_pages(). This way we wouldn't reduce the amount of memory usable (wasting RAM pages) for any of the external mappings anymore (and eliminate XSA-300) with "new Xen", but would be still functional ballooning out RAM pages with "old Xen". Also rename alloc(free)_xenballooned_pages to xen_alloc(free)_ballooned_pages and make xen_alloc(free)_unpopulated_pages static inline in xen.h if CONFIG_XEN_UNPOPULATED_ALLOC is disabled. Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/1639080336-26573-4-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-01-06xen/x86: obtain upper 32 bits of video frame buffer address for Dom0Jan Beulich
The hypervisor has been supplying this information for a couple of major releases. Make use of it. The need to set a flag in the capabilities field also points out that the prior setting of that field from the hypervisor interface's gbl_caps one was wrong, so that code gets deleted (there's also no equivalent of this in native boot code). Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/a3df8bf3-d044-b7bb-3383-cd5239d6d4af@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-01-03Merge 5.16-rc8 into usb-nextGreg Kroah-Hartman
We need the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-16xen/console: harden hvc_xen against event channel stormsJuergen Gross
The Xen console driver is still vulnerable for an attack via excessive number of events sent by the backend. Fix that by using a lateeoi event channel. For the normal domU initial console this requires the introduction of bind_evtchn_to_irq_lateeoi() as there is no xenbus device available at the time the event channel is bound to the irq. As the decision whether an interrupt was spurious or not requires to test for bytes having been read from the backend, move sending the event into the if statement, as sending an event without having found any bytes to be read is making no sense at all. This is part of XSA-391 Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> --- V2: - slightly adapt spurious irq detection (Jan Beulich) V3: - fix spurious irq detection (Jan Beulich)
2021-12-13usb: Add Xen pvUSB protocol descriptionJuergen Gross
Add the definition of pvUSB protocol used between the pvUSB frontend in a Xen domU and the pvUSB backend in a Xen driver domain (usually Dom0). This header was originally provided by Fujitsu for Xen based on Linux 2.6.18. Changes are: - adapt to Linux kernel style guide - use Xen namespace - add lots of comments - don't use kernel internal defines Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211123132048.5335-2-jgross@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-23xen: add "not_essential" flag to struct xenbus_driverJuergen Gross
When booting the xenbus driver will wait for PV devices to have connected to their backends before continuing. The timeout is different between essential and non-essential devices. Non-essential devices are identified by their nodenames directly in the xenbus driver, which requires to update this list in case a new device type being non-essential is added (this was missed for several types in the past). In order to avoid this problem, add a "not_essential" flag to struct xenbus_driver which can be set to "true" by the respective frontend. Set this flag for the frontends currently regarded to be not essential (vkbs and vfb) and use it for testing in the xenbus driver. Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211022064800.14978-2-jgross@suse.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-04xen/balloon: rename alloc/free_xenballooned_pagesJuergen Gross
alloc_xenballooned_pages() and free_xenballooned_pages() are used as direct replacements of xen_alloc_unpopulated_pages() and xen_free_unpopulated_pages() in case CONFIG_XEN_UNPOPULATED_ALLOC isn't defined. Guard both functions with !CONFIG_XEN_UNPOPULATED_ALLOC and rename them to the xen_*() variants they are replacing. This allows to remove some ifdeffery from the xen.h header file. Adapt the prototype of the functions to match. Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211102092234.17852-1-jgross@suse.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02xen: allow pv-only hypercalls only with CONFIG_XEN_PVJuergen Gross
Put the definitions of the hypercalls usable only by pv guests inside CONFIG_XEN_PV sections. On Arm two dummy functions related to pv hypercalls can be removed. While at it remove the no longer supported tmem hypercall definition. Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211028081221.2475-3-jgross@suse.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02xen-pciback: allow compiling on other archs than x86Oleksandr Andrushchenko
Xen-pciback driver was designed to be built for x86 only. But it can also be used by other architectures, e.g. Arm. Currently PCI backend implements multiple functionalities at a time, such as: 1. It is used as a database for assignable PCI devices, e.g. xl pci-assignable-{add|remove|list} manipulates that list. So, whenever the toolstack needs to know which PCI devices can be passed through it reads that from the relevant sysfs entries of the pciback. 2. It is used to hold the unbound PCI devices list, e.g. when passing through a PCI device it needs to be unbound from the relevant device driver and bound to pciback (strictly speaking it is not required that the device is bound to pciback, but pciback is again used as a database of the passed through PCI devices, so we can re-bind the devices back to their original drivers when guest domain shuts down) 3. Device reset for the devices being passed through 4. Para-virtualised use-cases support The para-virtualised part of the driver is not always needed as some architectures, e.g. Arm or x86 PVH Dom0, are not using backend-frontend model for PCI device passthrough. For such use-cases make the very first step in splitting the xen-pciback driver into two parts: Xen PCI stub and PCI PV backend drivers. For that add new configuration options CONFIG_XEN_PCI_STUB and CONFIG_XEN_PCIDEV_STUB, so the driver can be limited in its functionality, e.g. no support for para-virtualised scenario. x86 platform will continue using CONFIG_XEN_PCIDEV_BACKEND for the fully featured backend driver. Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Signed-off-by: Anastasiia Lukianenko <anastasiia_lukianenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211028143620.144936-1-andr2000@gmail.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02xen: fix wrong SPDX headers of Xen related headersJuergen Gross
Commit b24413180f5600 ("License cleanup: add SPDX GPL-2.0 license identifier to files with no license") was meant to do a tree-wide cleanup for files without any license information by adding a SPDX GPL-2.0 line to them. Unfortunately this was applied even to several Xen-related headers which have been originally under the MIT license, but obviously have been copied to the Linux tree from the Xen project without keeping the license boiler plate as required. Correct that by changing the license of those files back to "MIT". Some files still contain the MIT license text. Replace that by the related SPDX line. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20211015143312.29900-1-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-10-05xen/privcmd: drop "pages" parameter from xen_remap_pfn()Jan Beulich
The function doesn't use it and all of its callers say in a comment that their respective arguments are to be non-NULL only in auto-translated mode. Since xen_remap_domain_mfn_array() isn't supposed to be used by non-PV, drop the parameter there as well. It was bogusly passed as non- NULL (PRIV_VMA_LOCKED) by its only caller anyway. For xen_remap_domain_gfn_range(), otoh, it's not clear at all why this wouldn't want / might not need to gain auto-translated support down the road, so the parameter is retained there despite now remaining unused (and the only caller passing NULL); correct a respective comment as well. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/036ad8a2-46f9-ac3d-6219-bdc93ab9e10b@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2021-09-20swiotlb-xen: this is PV-only on x86Jan Beulich
The code is unreachable for HVM or PVH, and it also makes little sense in auto-translated environments. On Arm, with xen_{create,destroy}_contiguous_region() both being stubs, I have a hard time seeing what good the Xen specific variant does - the generic one ought to be fine for all purposes there. Still Arm code explicitly references symbols here, so the code will continue to be included there. Instead of making PCI_XEN's "select" conditional, simply drop it - SWIOTLB_XEN will be available unconditionally in the PV case anyway, and is - as explained above - dead code in non-PV environments. This in turn allows dropping the stubs for xen_{create,destroy}_contiguous_region(), the former of which was broken anyway - it failed to set the DMA handle output. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/5947b8ae-fdc7-225c-4838-84712265fc1e@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2021-07-05xen: sync include/xen/interface/io/ring.h with Xen's newest versionJuergen Gross
Sync include/xen/interface/io/ring.h with Xen's newest version in order to get the RING_COPY_RESPONSE() and RING_RESPONSE_PROD_OVERFLOW() macros. Note that this will correct the wrong license info by adding the missing original copyright notice. Signed-off-by: Juergen Gross <jgross@suse.com>
2021-05-14xen/arm: move xen_swiotlb_detect to arm/swiotlb-xen.hStefano Stabellini
Move xen_swiotlb_detect to a static inline function to make it available to !CONFIG_XEN builds. CC: boris.ostrovsky@oracle.com CC: jgross@suse.com Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20210512201823.1963-1-sstabellini@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com>
2021-05-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge yet more updates from Andrew Morton: "This is everything else from -mm for this merge window. 90 patches. Subsystems affected by this patch series: mm (cleanups and slub), alpha, procfs, sysctl, misc, core-kernel, bitmap, lib, compat, checkpatch, epoll, isofs, nilfs2, hpfs, exit, fork, kexec, gcov, panic, delayacct, gdb, resource, selftests, async, initramfs, ipc, drivers/char, and spelling" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (90 commits) mm: fix typos in comments mm: fix typos in comments treewide: remove editor modelines and cruft ipc/sem.c: spelling fix fs: fat: fix spelling typo of values kernel/sys.c: fix typo kernel/up.c: fix typo kernel/user_namespace.c: fix typos kernel/umh.c: fix some spelling mistakes include/linux/pgtable.h: few spelling fixes mm/slab.c: fix spelling mistake "disired" -> "desired" scripts/spelling.txt: add "overflw" scripts/spelling.txt: Add "diabled" typo scripts/spelling.txt: add "overlfow" arm: print alloc free paths for address in registers mm/vmalloc: remove vwrite() mm: remove xlate_dev_kmem_ptr() drivers/char: remove /dev/kmem for good mm: fix some typos and code style problems ipc/sem.c: mundane typo fixes ...
2021-05-07treewide: remove editor modelines and cruftMasahiro Yamada
The section "19) Editor modelines and other cruft" in Documentation/process/coding-style.rst clearly says, "Do not include any of these in source files." I recently receive a patch to explicitly add a new one. Let's do treewide cleanups, otherwise some people follow the existing code and attempt to upstream their favoriate editor setups. It is even nicer if scripts/checkpatch.pl can check it. If we like to impose coding style in an editor-independent manner, I think editorconfig (patch [1]) is a saner solution. [1] https://lore.kernel.org/lkml/20200703073143.423557-1-danny@kdrag0n.dev/ Link: https://lkml.kernel.org/r/20210324054457.1477489-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> [auxdisplay] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>