From 8b04825ed205da38754f86f4c07ea8600d8c2a65 Mon Sep 17 00:00:00 2001 From: Vincent Chen Date: Mon, 23 Sep 2019 08:45:14 +0800 Subject: riscv: avoid kernel hangs when trapped in BUG() When the CONFIG_GENERIC_BUG is disabled by disabling CONFIG_BUG, if a kernel thread is trapped by BUG(), the whole system will be in the loop that infinitely handles the ebreak exception instead of entering the die function. To fix this problem, the do_trap_break() will always call the die() to deal with the break exception as the type of break is BUG_TRAP_TYPE_BUG. Signed-off-by: Vincent Chen Reviewed-by: Christoph Hellwig Signed-off-by: Paul Walmsley --- arch/riscv/kernel/traps.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/riscv/kernel') diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 424eb72d56b1..055a937aca70 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -124,23 +124,23 @@ static inline unsigned long get_break_insn_length(unsigned long pc) asmlinkage void do_trap_break(struct pt_regs *regs) { -#ifdef CONFIG_GENERIC_BUG if (!user_mode(regs)) { enum bug_trap_type type; type = report_bug(regs->sepc, regs); switch (type) { +#ifdef CONFIG_GENERIC_BUG case BUG_TRAP_TYPE_NONE: break; case BUG_TRAP_TYPE_WARN: regs->sepc += get_break_insn_length(regs->sepc); break; case BUG_TRAP_TYPE_BUG: +#endif /* CONFIG_GENERIC_BUG */ + default: die(regs, "Kernel BUG"); } } -#endif /* CONFIG_GENERIC_BUG */ - force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)(regs->sepc)); } -- cgit v1.2.3