kernel/linux.git/drivers/virt/acrn, branch v6.1.124

drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map()

2024-06-12T09:03:30+00:00

[ Upstream commit 3d6586008f7b638f91f3332602592caa8b00b559 ] Patch series "mm: follow_pte() improvements and acrn follow_pte() fixes". Patch #1 fixes a bunch of issues I spotted in the acrn driver. It compiles, that's all I know. I'll appreciate some review and testing from acrn folks. Patch #2+#3 improve follow_pte(), passing a VMA instead of the MM, adding more sanity checks, and improving the documentation. Gave it a quick test on x86-64 using VM_PAT that ends up using follow_pte(). This patch (of 3): We currently miss handling various cases, resulting in a dangerous follow_pte() (previously follow_pfn()) usage. (1) We're not checking PTE write permissions. Maybe we should simply always require pte_write() like we do for pin_user_pages_fast(FOLL_WRITE)? Hard to tell, so let's check for ACRN_MEM_ACCESS_WRITE for now. (2) We're not rejecting refcounted pages. As we are not using MMU notifiers, messing with refcounted pages is dangerous and can result in use-after-free. Let's make sure to reject them. (3) We are only looking at the first PTE of a bigger range. We only lookup a single PTE, but memmap->len may span a larger area. Let's loop over all involved PTEs and make sure the PFN range is actually contiguous. Reject everything else: it couldn't have worked either way, and rather made use access PFNs we shouldn't be accessing. Link: https://lkml.kernel.org/r/20240410155527.474777-1-david@redhat.com Link: https://lkml.kernel.org/r/20240410155527.474777-2-david@redhat.com Fixes: 8a6e85f75a83 ("virt: acrn: obtain pa from VMA with PFNMAP flag") Signed-off-by: David Hildenbrand Cc: Alex Williamson Cc: Christoph Hellwig Cc: Fei Li Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Ingo Molnar Cc: Paolo Bonzini Cc: Yonghua Huang Cc: Sean Christopherson Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

virt: acrn: stop using follow_pfn

2024-06-12T09:03:30+00:00

[ Upstream commit 1b265da7ea1e1ae997fa119c2846bb389eb39c6b ] Patch series "remove follow_pfn". This series open codes follow_pfn in the only remaining caller, although the code there remains questionable. It then also moves follow_phys into the only user and simplifies it a bit. This patch (of 3): Switch from follow_pfn to follow_pte so that we can get rid of follow_pfn. Note that this doesn't fix any of the pre-existing raciness and lack of permission checking in the code. Link: https://lkml.kernel.org/r/20240324234542.2038726-1-hch@lst.de Link: https://lkml.kernel.org/r/20240324234542.2038726-2-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: David Hildenbrand Cc: Andy Lutomirski Cc: Dave Hansen Cc: Fei Li Cc: Peter Zijlstra Cc: Ingo Molnar Signed-off-by: Andrew Morton Stable-dep-of: 3d6586008f7b ("drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map()") Signed-off-by: Sasha Levin

virt: acrn: using for_each_set_bit to simplify the code

2022-07-08T13:42:10+00:00

It's more cleanly to use for_each_set_bit() instead of opencoding it. Signed-off-by: Yang Yingliang Signed-off-by: Fei Li Link: https://lore.kernel.org/r/20220704125044.2192381-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman

virt: acrn: Prefer array_size and struct_size over open coded arithmetic

2022-04-26T15:20:10+00:00

As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, use the array_size() helper to do the arithmetic instead of the argument "count * size" in the vzalloc() function. Also, take the opportunity to add a flexible array member of struct vm_memory_region_op to the vm_memory_region_batch structure. And then, change the code accordingly and use the struct_size() helper to do the arithmetic instead of the argument "size + size * count" in the kzalloc function. This code was detected with the help of Coccinelle and audited and fixed manually. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Acked-by: Fei Li Signed-off-by: Len Baker Signed-off-by: Gustavo A. R. Silva

virt: acrn: fix a memory leak in acrn_dev_ioctl()

2022-03-18T12:49:59+00:00

The vm_param and cpu_regs need to be freed via kfree() before return -EINVAL error. Fixes: 9c5137aedd11 ("virt: acrn: Introduce VM management interfaces") Fixes: 2ad2aaee1bc9 ("virt: acrn: Introduce an ioctl to set vCPU registers state") Signed-off-by: Xiaolong Huang Signed-off-by: Fei Li Link: https://lore.kernel.org/r/20220308092047.1008409-1-butterflyhuangxx@gmail.com Signed-off-by: Greg Kroah-Hartman

virt: acrn: obtain pa from VMA with PFNMAP flag

2022-03-18T12:49:56+00:00

acrn_vm_ram_map can't pin the user pages with VM_PFNMAP flag by calling get_user_pages_fast(), the PA(physical pages) may be mapped by kernel driver and set PFNMAP flag. This patch fixes logic to setup EPT mapping for PFN mapped RAM region by checking the memory attribute before adding EPT mapping for them. Fixes: 88f537d5e8dd ("virt: acrn: Introduce EPT mapping management") Signed-off-by: Yonghua Huang Signed-off-by: Fei Li Link: https://lore.kernel.org/r/20220228022212.419406-1-yonghua.huang@intel.com Signed-off-by: Greg Kroah-Hartman

virt: acrn: Remove unsued acrn_irqfds_mutex.

2022-03-18T12:49:49+00:00

acrn_irqfds_mutex is not used, never was. Remove acrn_irqfds_mutex. Fixes: aa3b483ff1d71 ("virt: acrn: Introduce irqfd") Cc: Fei Li Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/YidLo57Kw/u/cpA5@linutronix.de Signed-off-by: Greg Kroah-Hartman

all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate

2022-01-15T16:47:31+00:00

find_first{,_zero}_bit is a more effective analogue of 'next' version if start == 0. This patch replaces 'next' with 'first' where things look trivial. Signed-off-by: Yury Norov Tested-by: Wolfram Sang

virt: acrn: Introduce interfaces for virtual device creating/destroying

2021-10-05T14:14:10+00:00

The ACRN hypervisor can emulate a virtual device within hypervisor for a Guest VM. The emulated virtual device can work without the ACRN userspace after creation. The hypervisor do the emulation of that device. To support the virtual device creating/destroying, HSM provides the following ioctls: - ACRN_IOCTL_CREATE_VDEV Pass data struct acrn_vdev from userspace to the hypervisor, and inform the hypervisor to create a virtual device for a User VM. - ACRN_IOCTL_DESTROY_VDEV Pass data struct acrn_vdev from userspace to the hypervisor, and inform the hypervisor to destroy a virtual device of a User VM. These new APIs will be used by user space code vm_add_hv_vdev and vm_remove_hv_vdev in https://github.com/projectacrn/acrn-hypervisor/blob/master/devicemodel/core/vmmapi.c Signed-off-by: Shuo Liu Signed-off-by: Fei Li Link: https://lore.kernel.org/r/20210923084128.18902-3-fei1.li@intel.com Signed-off-by: Greg Kroah-Hartman

virt: acrn: Introduce interfaces for MMIO device passthrough

2021-10-05T14:14:10+00:00

MMIO device passthrough enables an OS in a virtual machine to directly access a MMIO device in the host. It promises almost the native performance, which is required in performance-critical scenarios of ACRN. HSM provides the following ioctls: - Assign - ACRN_IOCTL_ASSIGN_MMIODEV Pass data struct acrn_mmiodev from userspace to the hypervisor, and inform the hypervisor to assign a MMIO device to a User VM. - De-assign - ACRN_IOCTL_DEASSIGN_PCIDEV Pass data struct acrn_mmiodev from userspace to the hypervisor, and inform the hypervisor to de-assign a MMIO device from a User VM. These new APIs will be used by user space code vm_assign_mmiodev and vm_deassign_mmiodev in https://github.com/projectacrn/acrn-hypervisor/blob/master/devicemodel/core/vmmapi.c Signed-off-by: Shuo Liu Signed-off-by: Fei Li Link: https://lore.kernel.org/r/20210923084128.18902-2-fei1.li@intel.com Signed-off-by: Greg Kroah-Hartman