Fix(extra mem): Fix additonal memory allocation for MPU-based systems #196
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miguelafsilva5
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Code looks alright, but commit message is confusing.
Here's my proposal:
For MMU systems we manage the location counter to relocate VM images virtual address space.
This allows us to maintain a contiguous virtual address for each cpu between the hypervisor image and it’s private memory. However, for non-mmu systems this operation results in extra memory being erroneously allocated for the vms, as this space is already allocated between vm_image_start and vm_image_end.
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Shouldn't this also address calculations in |
For MMU systems we manage the location counter to relocate VM images virtual address space. This allows us to maintain a contiguous virtual address for each cpu between the hypervisor image and it’s private memory. However, for non-mmu systems this operation results in extra memory being erroneously allocated for the vms, as this space is already allocated between vm_image_start and vm_image_end. Signed-off-by: Miguel Silva <[email protected]>
In mmu-based systems, the vm_image_size is already encompassed in the image_size. This lead to miscalculations in the base address of the bitmap and cpu. Signed-off-by: Miguel Silva <[email protected]>
Having this symbol right before the bss section (firs noload section) allows easier calculations in the c code. Signed-off-by: Miguel Silva <[email protected]>
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PR description
This PR fixes a problem identified for systems based on MPUs, where additional memory was being allocated for VMs in the linkerscript. This is only required for MMU-based ones.
Additionally, this PR also fixes a small mistake where the root pool bitmap base was being allocated in a wrong place for systems with MPU.