kernel/mm: Reduce stack footprint of page-table freeing #442
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Freax13
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Turns out that the way the iterators are implemented in RawPageTablePart::free_lvl*() the compiler makes copies of entire pages on the stack, which overflows the 32 KiB stack pretty quickly. Iterate over references only and significantly reduce stack usage of the page-table freeing code. Signed-off-by: Joerg Roedel <[email protected]>
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Turns out that the way the iterators are implemented in RawPageTablePart::free_lvl*() the compiler makes copies of entire pages on the stack, which overflows the 32 KiB stack pretty quickly.
Iterate over references only and significantly reduce stack usage of the page-table freeing code.