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s390/setup: avoid reserving memory above identity mapping

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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: 73045a08cf55 ("s390: unify identity mapping limits handling")
Reported-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This commit is contained in:
Vasily Gorbik 2021-10-14 13:33:45 +02:00 committed by Heiko Carstens
parent fa55b7dcdc
commit 420f48f636
1 changed files with 1 additions and 9 deletions
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10
arch/s390/kernel/setup.c
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@ -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 */