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From:   Andreas Schwab <schwab@suse.de>
To:     Celeste Liu <coelacanthushex@gmail.com>
Cc:     Palmer Dabbelt <palmer@rivosinc.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Albert Ou <aou@eecs.berkeley.edu>, Guo Ren <guoren@kernel.org>,
        =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@rivosinc.com>,
        Conor Dooley <conor.dooley@microchip.com>,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        Felix Yan <felixonmars@archlinux.org>,
        Ruizhe Pan <c141028@gmail.com>,
        Shiqi Zhang <shiqi@isrc.iscas.ac.cn>
Subject: Re: [PATCH v3] riscv: entry: set a0 = -ENOSYS only when syscall != -1
In-Reply-To: <20230718210037.250665-1-CoelacanthusHex@gmail.com> (Celeste
        Liu's message of "Wed, 19 Jul 2023 04:57:30 +0800")
References: <20230718210037.250665-1-CoelacanthusHex@gmail.com>
Date:   Wed, 19 Jul 2023 09:21:43 +0200
Message-ID: <mvmo7k8cqns.fsf@suse.de>
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On Jul 19 2023, Celeste Liu wrote:

> @@ -308,7 +312,7 @@ asmlinkage __visible __trap_section void do_trap_ecall_u(struct pt_regs *regs)
>  
>  		if (syscall < NR_syscalls)
>  			syscall_handler(regs, syscall);
> -		else
> +		else if ((long)syscall != -1L)

You can also use syscall != -1UL or even syscall != -1.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."