From: Jisheng Zhang <jszhang@xxxxxxxxxx>
[ Upstream commit b690e266dae2f85f4dfea21fa6a05e3500a51054 ]
lkp reports below sparse warning when building for RV32:
arch/riscv/mm/init.c:1204:48: sparse: warning: cast truncates bits from
constant value (100000000 becomes 0)
IMO, the reason we didn't see this truncates bug in real world is "0"
means MEMBLOCK_ALLOC_ACCESSIBLE in memblock and there's no RV32 HW
with more than 4GB memory.
Fix it anyway to make sparse happy.
Fixes: decf89f86ecd ("riscv: try to allocate crashkern region from 32bit addressible memory")
Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202306080034.SLiCiOMn-lkp@xxxxxxxxx/
Link: https://lore.kernel.org/r/20230709171036.1906-1-jszhang@xxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/riscv/mm/init.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index f8bfbe983517c..d7115acab3501 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -843,7 +843,7 @@ static void __init reserve_crashkernel(void)
*/
crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
search_start,
- min(search_end, (unsigned long) SZ_4G));
+ min(search_end, (unsigned long)(SZ_4G - 1)));
if (crash_base == 0) {
/* Try again without restricting region to 32bit addressible memory */
crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
--
2.39.2
