We want to rework how set_pXd() behaves for generic compile-time
folded page tables by disallowing its use and triggering a compile-time
error when it is used improperly, ensuring that the actual first-level
set_pXd() function is used instead.

Therefore, call the proper set_pXd() in case of generic compile-time
folded pgtable to handle vmalloc_fault() with pXd_present().

There should be no functional change.

Signed-off-by: Yeoreum Yun <[email protected]>
---
 arch/riscv/mm/fault.c | 52 +++++++++++++++++++++++++++----------------
 1 file changed, 33 insertions(+), 19 deletions(-)

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 04ed6f8acae4f..b2bcaf10d13f1 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -167,14 +167,16 @@ bad_area(struct pt_regs *regs, struct mm_struct *mm, int 
code,
 
 static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long 
addr)
 {
-       pgd_t *pgd, *pgd_k;
-       pud_t *pud_k;
-       p4d_t *p4d_k;
-       pmd_t *pmd_k;
-       pte_t *pte_k;
+       pgd_t *pgdp_k, *pgdp, pgd_k;
+       p4d_t *p4dp_k, *p4dp;
+       pud_t *pudp_k, *pudp, pud_k;
+       pmd_t *pmdp_k, *pmdp, pmd_k;
+       pte_t *ptep_k;
        int index;
        unsigned long pfn;
 
+       BUILD_BUG_ON(CONFIG_PGTABLE_LEVELS != 5 && CONFIG_PGTABLE_LEVELS != 2);
+
        /* User mode accesses just cause a SIGSEGV */
        if (user_mode(regs))
                return do_trap(regs, SIGSEGV, code, addr);
@@ -189,39 +191,51 @@ static inline void vmalloc_fault(struct pt_regs *regs, 
int code, unsigned long a
         */
        index = pgd_index(addr);
        pfn = csr_read(CSR_SATP) & SATP_PPN;
-       pgd = (pgd_t *)pfn_to_virt(pfn) + index;
-       pgd_k = init_mm.pgd + index;
 
-       if (!pgd_present(pgdp_get(pgd_k))) {
+       pgdp = (pgd_t *)pfn_to_virt(pfn) + index;
+       pgdp_k = init_mm.pgd + index;
+
+       pgd_k = pgdp_get(pgdp_k);
+       if (!pgd_present(pgd_k)) {
                no_context(regs, addr);
                return;
        }
-       set_pgd(pgd, pgdp_get(pgd_k));
+       if (CONFIG_PGTABLE_LEVELS == 5)
+               set_pgd(pgdp, pgd_k);
 
-       p4d_k = p4d_offset(pgd_k, addr);
-       if (!p4d_present(p4dp_get(p4d_k))) {
+       p4dp = p4d_offset(pgdp, addr);
+       p4dp_k = p4d_offset(pgdp_k, addr);
+       if (!p4d_present(p4dp_get(p4dp_k))) {
                no_context(regs, addr);
                return;
        }
 
-       pud_k = pud_offset(p4d_k, addr);
-       if (!pud_present(pudp_get(pud_k))) {
+       pudp = pud_offset(p4dp, addr);
+       pudp_k = pud_offset(p4dp_k, addr);
+
+       pud_k = pudp_get(pudp_k);
+       if (!pud_present(pud_k)) {
                no_context(regs, addr);
                return;
        }
-       if (pud_leaf(pudp_get(pud_k)))
+       if (pud_leaf(pud_k))
                goto flush_tlb;
 
        /*
         * Since the vmalloc area is global, it is unnecessary
         * to copy individual PTEs
         */
-       pmd_k = pmd_offset(pud_k, addr);
-       if (!pmd_present(pmdp_get(pmd_k))) {
+       pmdp = pmd_offset(pudp, addr);
+       pmdp_k = pmd_offset(pudp_k, addr);
+
+       pmd_k = pmdp_get(pmdp_k);
+       if (!pmd_present(pmd_k)) {
                no_context(regs, addr);
                return;
        }
-       if (pmd_leaf(pmdp_get(pmd_k)))
+       if (CONFIG_PGTABLE_LEVELS == 2)
+               set_pmd(pmdp, pmd_k);
+       if (pmd_leaf(pmd_k))
                goto flush_tlb;
 
        /*
@@ -230,8 +244,8 @@ static inline void vmalloc_fault(struct pt_regs *regs, int 
code, unsigned long a
         * addresses. If we don't do this, this will just
         * silently loop forever.
         */
-       pte_k = pte_offset_kernel(pmd_k, addr);
-       if (!pte_present(ptep_get(pte_k))) {
+       ptep_k = pte_offset_kernel(pmdp_k, addr);
+       if (!pte_present(ptep_get(ptep_k))) {
                no_context(regs, addr);
                return;
        }
-- 
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}


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