s390/boot: fix mem_detect extended area allocation

Allocation of mem_detect extended area was not considered neither
in commit 9641b8cc733f ("s390/ipl: read IPL report at early boot")
nor in commit b2d24b97b2a9 ("s390/kernel: add support for kernel address
space layout randomization (KASLR)"). As a result mem_detect extended
theoretically may overlap with ipl report or randomized kernel image
position. But as mem_detect code will allocate extended area only
upon exceeding 255 online regions (which should alternate with offline
memory regions) it is not seen in practice.

To make sure mem_detect extended area does not overlap with ipl report
or randomized kernel position extend usage of "safe_addr". Make initrd
handling and mem_detect extended area allocation code move it further
right and make KASLR takes in into consideration as well.

Fixes: 9641b8cc733f ("s390/ipl: read IPL report at early boot")
Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index 830cfabaa6a0..939d27da8fbd 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -33,10 +33,10 @@ struct vmlinux_info {
 };
 
 void startup_kernel(void);
-unsigned long detect_memory(void);
+unsigned long detect_memory(unsigned long *safe_addr);
 bool is_ipl_block_dump(void);
 void store_ipl_parmblock(void);
-unsigned long read_ipl_report(unsigned long safe_offset);
+unsigned long read_ipl_report(unsigned long safe_addr);
 void setup_boot_command_line(void);
 void parse_boot_command_line(void);
 void verify_facilities(void);