From: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> commit 1ff5c8e8c835e8a81c0868e3050c76563dd56a2c upstream. This reverts commit 602946ec2f90d5bd965857753880db29d2d9a1e9. If CONFIG_HIGHMEM is enabled, no highmem will be added with max_mapnr set to max_low_pfn, see mem_init(): for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { ... free_highmem_page(); } Now that virt_addr_valid() has been fixed in the previous commit, we can revert the change to max_mapnr. Fixes: 602946ec2f90 ("powerpc: Set max_mapnr correctly") Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Reported-by: Erhard F. <erhard_f@xxxxxxxxxxx> [mpe: Update change log to reflect series reordering] Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220406145802.538416-2-mpe@xxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/mm/mem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -255,7 +255,7 @@ void __init mem_init(void) #endif high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); - set_max_mapnr(max_low_pfn); + set_max_mapnr(max_pfn); kasan_late_init(); Patches currently in stable-queue which might be from wangkefeng.wang@xxxxxxxxxx are queue-5.17/revert-powerpc-set-max_mapnr-correctly.patch