If a caller tries to unmap a single page which is already part of an unmapped block, set_one_region() will panic since there isn't a valid block or table to contain the page. Detect this case explicitly and return since no action needs to be taken.
Signed-off-by: Casey Connolly <[email protected]> --- Depends on my previous series which fixes unmapping regions https://lore.kernel.org/u-boot/[email protected]/ --- arch/arm/cpu/armv8/cache_v8.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c index 6c85022556ad..472887b5d99b 100644 --- a/arch/arm/cpu/armv8/cache_v8.c +++ b/arch/arm/cpu/armv8/cache_v8.c @@ -1003,8 +1003,13 @@ static u64 set_one_region(u64 start, u64 size, u64 attrs, bool flag, int level) int levelshift = level2shift(level); u64 levelsize = 1ULL << levelshift; u64 *pte = find_pte(start, level); + /* Trying to unmap a region which is part of an already unmapped block, nothing to do */ + if (pte_type(pte) == PTE_TYPE_FAULT && attrs == PTE_TYPE_FAULT && size < levelsize) { + return size; + } + /* Can we can just modify the current level block/page? */ if (is_aligned(start, size, levelsize)) { if (attrs == PTE_TYPE_FAULT) { if (pte_type(pte) == PTE_TYPE_TABLE && level < 3) -- 2.53.0
