diff options
Diffstat (limited to 'na/arch/riscv/trap/trap_vector.S')
| -rw-r--r-- | na/arch/riscv/trap/trap_vector.S | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/na/arch/riscv/trap/trap_vector.S b/na/arch/riscv/trap/trap_vector.S index 160b122..8e45cae 100644 --- a/na/arch/riscv/trap/trap_vector.S +++ b/na/arch/riscv/trap/trap_vector.S @@ -90,6 +90,15 @@ trap_vector: /* Step 6: flush TLB after page table switch */ sfence.vma zero, zero + /* Step 6.5: restore kernel gp (global pointer). + * The compiler uses gp-relative addressing for global variable access + * (e.g. ld reg, offset(gp)). User mode may have set gp to anything, + * so we MUST reload it before entering any C++ code. */ +.option push +.option norelax + la gp, __global_pointer$ +.option pop + /* Pass TrapFrame* to C++ handler (a0 = tf) */ mv a0, tp @@ -97,7 +106,6 @@ trap_vector: mv tp, t2 /* Step 7: jump to C++ trap_handler */ - /* Step 7: jump to C++ trap_handler */ jalr t3 |