This is a note to let you know that I've just added the patch titled
s390/mem_detect: fix detect_memory() error handling
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
s390-mem_detect-fix-detect_memory-error-handling.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9be8eb14960641f60356e58b656a94f5e0b8da8b
Author: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Date: Fri Jan 27 14:03:07 2023 +0100
s390/mem_detect: fix detect_memory() error handling
[ Upstream commit 3400c35a4090704e6c465449616ab7e67a9209e7 ]
Currently if for some reason sclp_early_read_info() fails,
sclp_early_get_memsize() will not set max_physmem_end and it
will stay uninitialized. Any garbage value other than 0 will lead
to detect_memory() taking wrong path or returning a garbage value
as max_physmem_end. To avoid that simply initialize max_physmem_end.
Fixes: 73045a08cf55 ("s390: unify identity mapping limits handling")
Reported-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Reviewed-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/s390/boot/mem_detect.c b/arch/s390/boot/mem_detect.c
index 2f949cd9076b8..17a32707d17e0 100644
--- a/arch/s390/boot/mem_detect.c
+++ b/arch/s390/boot/mem_detect.c
@@ -165,7 +165,7 @@ static void search_mem_end(void)
unsigned long detect_memory(void)
{
- unsigned long max_physmem_end;
+ unsigned long max_physmem_end = 0;
sclp_early_get_memsize(&max_physmem_end);
