s390/setup: don't reserve memory that occupied decompressor's head
authorAlexander Egorenkov <egorenar@linux.ibm.com>
Wed, 16 Jun 2021 12:10:03 +0000 (14:10 +0200)
committerHeiko Carstens <hca@linux.ibm.com>
Tue, 27 Jul 2021 07:39:17 +0000 (09:39 +0200)
There is no useful information within [STARTUP_NORMAL_OFFSET, HEAD_END] now.

But the memory region [0, STARTUP_NORMAL_OFFSET] is used by:
* lowcore
* kdump for swapping memory
* stand-alone zipl dumpers for code, data, stack and heap

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
arch/s390/kernel/setup.c

index 32d1324..c5bbf96 100644 (file)
@@ -797,7 +797,7 @@ static void __init reserve_kernel(void)
 {
        unsigned long start_pfn = PFN_UP(__pa(_end));
 
-       memblock_reserve(0, HEAD_END);
+       memblock_reserve(0, STARTUP_NORMAL_OFFSET);
        memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
                         - (unsigned long)_stext);
 }