| Message ID | 20220716115059.3509-2-jszhang@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | use static key to optimize pgtable_l4_enabled | expand |
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index f0f36a4a0e9b..f5762f7b982d 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -269,6 +269,7 @@ void __init setup_arch(char **cmdline_p) *cmdline_p = boot_command_line; early_ioremap_setup(); + sbi_init(); jump_label_init(); parse_early_param(); @@ -285,7 +286,6 @@ void __init setup_arch(char **cmdline_p) misc_mem_init(); init_resources(); - sbi_init(); #ifdef CONFIG_KASAN kasan_init();
We call jump_label_init() in setup_arch() is to use static key mechanism earlier, but riscv jump label relies on the sbi functions, If we enable static key before sbi_init(), the code path looks like: static_branch_enable() .. arch_jump_label_transform() patch_text_nosync() flush_icache_range() flush_icache_all() sbi_remote_fence_i() for CONFIG_RISCV_SBI case __sbi_rfence() Since sbi isn't initialized, so NULL deference! Here is a typical panic log: [ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 0.000000] Oops [#1] [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0-rc7+ #79 [ 0.000000] Hardware name: riscv-virtio,qemu (DT) [ 0.000000] epc : 0x0 [ 0.000000] ra : sbi_remote_fence_i+0x1e/0x26 [ 0.000000] epc : 0000000000000000 ra : ffffffff80005826 sp : ffffffff80c03d50 [ 0.000000] gp : ffffffff80ca6178 tp : ffffffff80c0ad80 t0 : 6200000000000000 [ 0.000000] t1 : 0000000000000000 t2 : 62203a6b746e6972 s0 : ffffffff80c03d60 [ 0.000000] s1 : ffffffff80001af6 a0 : 0000000000000000 a1 : 0000000000000000 [ 0.000000] a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000 [ 0.000000] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000080200 [ 0.000000] s2 : ffffffff808b3e48 s3 : ffffffff808bf698 s4 : ffffffff80cb2818 [ 0.000000] s5 : 0000000000000001 s6 : ffffffff80c9c345 s7 : ffffffff80895aa0 [ 0.000000] s8 : 0000000000000001 s9 : 000000000000007f s10: 0000000000000000 [ 0.000000] s11: 0000000000000000 t3 : ffffffff80824d08 t4 : 0000000000000022 [ 0.000000] t5 : 000000000000003d t6 : 0000000000000000 [ 0.000000] status: 0000000000000100 badaddr: 0000000000000000 cause: 000000000000000c [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Fix this issue by moving sbi_init() earlier before jump_label_init() Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> --- arch/riscv/kernel/setup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)