Commit 420f48f6 authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Heiko Carstens
Browse files

s390/setup: avoid reserving memory above identity mapping 



Such reserved memory region, if not cleaned up later causes problems when
memblock_free_all() is called to release free pages to the buddy allocator
and those reserved regions are carried over to reserve_bootmem_region()
which marks the pages as PageReserved.

Instead use memblock_set_current_limit() to make sure memblock allocations
do not go over identity mapping (which could happen when "mem=" option
is used or during kdump).

Cc: stable@vger.kernel.org
Fixes: 73045a08 ("s390: unify identity mapping limits handling")
Reported-by: default avatarGerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent fa55b7dc

arch/s390/kernel/setup.c

+1 −9
Original line number Diff line number Diff line
@@ -637,14 +637,6 @@ static struct notifier_block kdump_mem_nb = { 


#endif



/*

 * Make sure that the area above identity mapping is protected

 */

static void __init reserve_above_ident_map(void)

{

	memblock_reserve(ident_map_size, ULONG_MAX);

}



/*

 * Reserve memory for kdump kernel to be loaded with kexec

 */
@@ -999,11 +991,11 @@ void __init setup_arch(char **cmdline_p) 
	setup_control_program_code();



	/* Do some memory reservations *before* memory is added to memblock */

	reserve_above_ident_map();

	reserve_kernel();

	reserve_initrd();

	reserve_certificate_list();

	reserve_mem_detect_info();

	memblock_set_current_limit(ident_map_size);

	memblock_allow_resize();



	/* Get information about *all* installed memory */