Unaligned access exception can be triggered in irq-enabled context such as user mode, in this case do_ale() may call get_user() which may cause sleep. Then we will get:
BUG: sleeping function called from invalid context at arch/loongarch/kernel/access-helper.h:7 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 129, name: modprobe preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 CPU: 0 UID: 0 PID: 129 Comm: modprobe Tainted: G W 6.12.0-rc1+ #1723 Tainted: [W]=WARN Stack : 9000000105e0bd48 0000000000000000 9000000003803944 9000000105e08000 9000000105e0bc70 9000000105e0bc78 0000000000000000 0000000000000000 9000000105e0bc78 0000000000000001 9000000185e0ba07 9000000105e0b890 ffffffffffffffff 9000000105e0bc78 73924b81763be05b 9000000100194500 000000000000020c 000000000000000a 0000000000000000 0000000000000003 00000000000023f0 00000000000e1401 00000000072f8000 0000007ffbb0e260 0000000000000000 0000000000000000 9000000005437650 90000000055d5000 0000000000000000 0000000000000003 0000007ffbb0e1f0 0000000000000000 0000005567b00490 0000000000000000 9000000003803964 0000007ffbb0dfec 00000000000000b0 0000000000000007 0000000000000003 0000000000071c1d ... Call Trace: [<9000000003803964>] show_stack+0x64/0x1a0 [<9000000004c57464>] dump_stack_lvl+0x74/0xb0 [<9000000003861ab4>] __might_resched+0x154/0x1a0 [<900000000380c96c>] emulate_load_store_insn+0x6c/0xf60 [<9000000004c58118>] do_ale+0x78/0x180 [<9000000003801bc8>] handle_ale+0x128/0x1e0
So enable IRQ if unaligned access exception is triggered in irq-enabled context to fix it.
Cc: stable@vger.kernel.org Reported-by: Binbin Zhou zhoubinbin@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn --- arch/loongarch/kernel/traps.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/arch/loongarch/kernel/traps.c b/arch/loongarch/kernel/traps.c index f9f4eb00c92e..c57b4134f3e8 100644 --- a/arch/loongarch/kernel/traps.c +++ b/arch/loongarch/kernel/traps.c @@ -555,6 +555,9 @@ asmlinkage void noinstr do_ale(struct pt_regs *regs) #else unsigned int *pc;
+ if (regs->csr_prmd & CSR_PRMD_PIE) + local_irq_enable(); + perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, regs->csr_badvaddr);
/* @@ -579,6 +582,8 @@ asmlinkage void noinstr do_ale(struct pt_regs *regs) die_if_kernel("Kernel ale access", regs); force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)regs->csr_badvaddr); out: + if (regs->csr_prmd & CSR_PRMD_PIE) + local_irq_disable(); #endif irqentry_exit(regs, state); }