[PATCH AUTOSEL 5.3 53/89] riscv: avoid sending a SIGTRAP to a user thread trapped in WARN()

[Sasha Levin]

From: Vincent Chen <vincent.chen@xxxxxxxxxx>

[ Upstream commit e0c0fc18f10d5080cddde0e81505fd3e952c20c4 ]

On RISC-V, when the kernel runs code on behalf of a user thread, and the
kernel executes a WARN() or WARN_ON(), the user thread will be sent
a bogus SIGTRAP.  Fix the RISC-V kernel code to not send a SIGTRAP when
a WARN()/WARN_ON() is executed.

Signed-off-by: Vincent Chen <vincent.chen@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
[paul.walmsley@xxxxxxxxxx: fixed subject]
Signed-off-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/riscv/kernel/traps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 055a937aca70a..82f42a55451eb 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -134,7 +134,7 @@ asmlinkage void do_trap_break(struct pt_regs *regs)
 			break;
 		case BUG_TRAP_TYPE_WARN:
 			regs->sepc += get_break_insn_length(regs->sepc);
-			break;
+			return;
 		case BUG_TRAP_TYPE_BUG:
 #endif /* CONFIG_GENERIC_BUG */
 		default:
-- 
2.20.1