Re: [Qemu-arm] Panic when PCI trying to read secure mem area.

[Peter Maydell]

On Sun, 31 Mar 2019 at 05:22, ratna manoj <address@hidden> wrote:
> I am getting a kernel panic when PCI is trying to read at 0xe0880000 in 
> VIRT_SECURE_MEM area. ([VIRT_SECURE_MEM] = { 0x0e000000, 0x01000000 })

Hi. The address 0xe0880000 is not in the range starting at
                0x0e000000
-- I suspect you've miscounted your zeroes. So whatever is going
wrong, it's probably not the fault of the VIRT_SECURE_MEM block.

I see you've already figured out that the answer is to pass
-machine highmem=off. By default the virt board creates
PCI windows in areas of physical address space above the 4GB mark
and advertises them in the device tree. Some older kernel versions
are buggy when configured without LPAE support, and instead of
correctly identifying that they can't reach these PCI windows
and ignoring them, they truncate the addresses to 32 bits and
try to access PCI at bogus addresses. The other ways to fix this
are to build your guest kernel with LPAE support enabled, or to
use a new enough kernel that has the bug fixed.

PS: I recommend against using 'secure=on' unless you have a
specific strong reason to want to run in the Secure world.
The expected and more tested configuration for "I just want
to boot a Linux guest" is the default (secure=off).

thanks
-- PMM