[PATCH AUTOSEL 5.15 032/153] um: Update min_low_pfn to match changes in uml_reserved

[Sasha Levin <sashal@kernel.org>]

From: Tiwei Bie <tiwei.btw@antgroup.com>

[ Upstream commit e82cf3051e6193f61e03898f8dba035199064d36 ]

When uml_reserved is updated, min_low_pfn must also be updated
accordingly. Otherwise, min_low_pfn will not accurately reflect
the lowest available PFN.

Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20250221041855.1156109-1-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/um/kernel/mem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 8e636ce029495..50be04f7b40f3 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -49,6 +49,7 @@ void __init mem_init(void)
 	map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
 	memblock_free(__pa(brk_end), uml_reserved - brk_end);
 	uml_reserved = brk_end;
+	min_low_pfn = PFN_UP(__pa(uml_reserved));
 
 	/* this will put all low memory onto the freelists */
 	memblock_free_all();
-- 
2.39.5