[PATCH 5.18 006/879] RISC-V: Mark IORESOURCE_EXCLUSIVE for reserved mem instead of IORESOURCE_BUSY

[Greg Kroah-Hartman]

From: Xianting Tian <xianting.tian@xxxxxxxxxxxxxxxxx>

commit e61bf5c071148c80d091f8e7220b3b9130780ae3 upstream.

Commit 00ab027a3b82 ("RISC-V: Add kernel image sections to the resource tree")
marked IORESOURCE_BUSY for reserved memory, which caused resource map
failed in subsequent operations of related driver, so remove the
IORESOURCE_BUSY flag. In order to prohibit userland mapping reserved
memory, mark IORESOURCE_EXCLUSIVE for it.

The code to reproduce the issue,
dts:
        mem0: memory@a0000000 {
                reg = <0x0 0xa0000000 0 0x1000000>;
                no-map;
        };

        &test {
                status = "okay";
                memory-region = <&mem0>;
        };

code:
        np = of_parse_phandle(pdev->dev.of_node, "memory-region", 0);
        ret = of_address_to_resource(np, 0, &r);
        base = devm_ioremap_resource(&pdev->dev, &r);
        // base = -EBUSY

Fixes: 00ab027a3b82 ("RISC-V: Add kernel image sections to the resource tree")
Reported-by: Huaming Jiang <jianghuaming.jhm@xxxxxxxxxxxxxxx>
Reviewed-by: Guo Ren <guoren@xxxxxxxxxx>
Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx>
Tested-by: Heiko Stuebner <heiko@xxxxxxxxx>
Co-developed-by: Nick Kossifidis <mick@xxxxxxxxxxxx>
Signed-off-by: Xianting Tian <xianting.tian@xxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220518013428.1338983-1-xianting.tian@xxxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/riscv/kernel/setup.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -189,7 +189,7 @@ static void __init init_resources(void)
 		res = &mem_res[res_idx--];
 
 		res->name = "Reserved";
-		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+		res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 		res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region));
 		res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1;
 
@@ -214,7 +214,7 @@ static void __init init_resources(void)
 
 		if (unlikely(memblock_is_nomap(region))) {
 			res->name = "Reserved";
-			res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+			res->flags = IORESOURCE_MEM | IORESOURCE_EXCLUSIVE;
 		} else {
 			res->name = "System RAM";
 			res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;