Commit Graph

3 Commits

Author SHA1 Message Date
Len Baker 746f1b0ac5 virt: acrn: Prefer array_size and struct_size over open coded arithmetic
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 <fei1.li@intel.com>
Signed-off-by: Len Baker <len.baker@gmx.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2022-04-26 10:20:10 -05:00
Yonghua Huang 8a6e85f75a virt: acrn: obtain pa from VMA with PFNMAP flag
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: 88f537d5e8 ("virt: acrn: Introduce EPT mapping management")
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Signed-off-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20220228022212.419406-1-yonghua.huang@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 13:49:56 +01:00
Shuo Liu 88f537d5e8 virt: acrn: Introduce EPT mapping management
The HSM provides hypervisor services to the ACRN userspace. While
launching a User VM, ACRN userspace needs to allocate memory and request
the ACRN Hypervisor to set up the EPT mapping for the VM.

A mapping cache is introduced for accelerating the translation between
the Service VM kernel virtual address and User VM physical address.

>From the perspective of the hypervisor, the types of GPA of User VM can be
listed as following:
   1) RAM region, which is used by User VM as system ram.
   2) MMIO region, which is recognized by User VM as MMIO. MMIO region is
      used to be utilized for devices emulation.

Generally, User VM RAM regions mapping is set up before VM started and
is released in the User VM destruction. MMIO regions mapping may be set
and unset dynamically during User VM running.

To achieve this, ioctls ACRN_IOCTL_SET_MEMSEG and ACRN_IOCTL_UNSET_MEMSEG
are introduced in HSM.

Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-9-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-09 10:58:19 +01:00