s390/dump: fix old lowcore virtual vs physical address confusion

stable inclusion
from stable-v5.10.137
commit ae921d176b6f4359ac7462406ea68293c8c1c84e
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ae921d176b6f4359ac7462406ea68293c8c1c84e



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[ Upstream commit dc306186 ]

Virtual addresses of vmcore_info and os_info members are
wrongly passed to copy_oldmem_kernel(), while the function
expects physical address of the source. Instead, __pa()
macro should have been applied.

Yet, use of __pa() macro could be somehow confusing, since
copy_oldmem_kernel() may treat the source as an offset, not
as a direct physical address (that depens from the oldmem
availability and location).

Fix the virtual vs physical address confusion and make the
way the old lowcore is read consistent across all sources.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>