riscv: correct pt_level name via pgtable_l5/4_enabled

commit e59e5e2754bf983fc58ad18f99b5eec01f1a0745 upstream.

The pt_level uses CONFIG_PGTABLE_LEVELS to display page table names.
But if page mode is downgraded from kernel cmdline or restricted by
the hardware in 64BIT, it will give a wrong name.

Like, using no4lvl for sv39, ptdump named the 1G-mapping as "PUD"
that should be "PGD":

0xffffffd840000000-0xffffffd900000000    0x00000000c0000000         3G PUD     D A G . . W R V

So select "P4D/PUD" or "PGD" via pgtable_l5/4_enabled to correct it.

Fixes: e8a62cc26ddf ("riscv: Implement sv48 support")
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Song Shuai <suagrfillet@gmail.com>
Link: https://lore.kernel.org/r/20230712115740.943324-1-suagrfillet@gmail.com
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230830044129.11481-3-palmer@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c
index 20a9f99..e9090b3 100644 (file)
--- a/arch/riscv/mm/ptdump.c
+++ b/arch/riscv/mm/ptdump.c
@@ -384,6 +384,9 @@ static int __init ptdump_init(void)
 
        kernel_ptd_info.base_addr = KERN_VIRT_START;
 
+       pg_level[1].name = pgtable_l5_enabled ? "P4D" : "PGD";
+       pg_level[2].name = pgtable_l4_enabled ? "PUD" : "PGD";
+
        for (i = 0; i < ARRAY_SIZE(pg_level); i++)
                for (j = 0; j < ARRAY_SIZE(pte_bits); j++)
                        pg_level[i].mask |= pte_bits[j].mask;