From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E21DD2361DD for ; Tue, 14 Jan 2025 13:00:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736859623; cv=none; b=k4/pm1+AjymUrgyCk6Vxkhyn/XMDtBR5N/NqDTAA84PzXuaVd8DDjRDTCcqHRWcaQ1S3rou7B1NMqU/+CSUUILJduSzvT8SsEj3GtSIOHsHTfW7MJ6pE6T+UvFcq6yfCGncP9Um9sqhu04pjnet3csTWn6ttKVbAQnt8k+T875U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736859623; c=relaxed/simple; bh=+UlpBfqj09Ly2utYLljGHX1TZBMJZ1VPjWkhmJ5SGCM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DzXB7hgbW7CSoGKYVssE5I8S7sHBd430lGJxoYlaEhDnzXZzLMgHKD9ejsRkUgxMfuFGDZOVRIlr2RWsHMuMorVyjhyzuaWEA5owA0hGT1laLlLU7vfXZTsoiEFPL0WrQEu2pToC1gWFLco7IAkvFllcGyDGz8stFaMysnmrkwc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hUQMUivY; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hUQMUivY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 840EEC4CEE1; Tue, 14 Jan 2025 13:00:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736859622; bh=+UlpBfqj09Ly2utYLljGHX1TZBMJZ1VPjWkhmJ5SGCM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hUQMUivYASPw9qQFM/e4VX79K2W9eewh7bfXl0dnO6oUVTGozhNaASX2u5UXt5HMp ihVWBeJTuq6afv//5nQddLokkTETSesMREcqXfUP3FpPn2MaAXCrm0w/AteokjQr4T u3fRLFA9sv+lgmjktrw+x3l4aQnjcqhy7cwuZuS+HPdtFeub36+k4QKzMppTD8xTvf zZIwU0LyNUvPngKAUnNDCk2t6bDr8bb62Cwu1tehiBj7bfw+x6f9jzZAGxbSPZMTmO uwXHp3MTBEl8RC5FJE88MM9DnZuAKiuamVJL5CJPOA/wlLNaPaTB+8eD6Q9dzm4Zvg F2xwMCmvwIbdw== Date: Tue, 14 Jan 2025 14:00:16 +0100 From: Alexey Gladkov To: "Dmitry V. Levin" Cc: Oleg Nesterov , Michael Ellerman , Eugene Syromyatnikov , Mike Frysinger , Renzo Davoli , Davide Berardi , strace-devel@lists.strace.io, Madhavan Srinivasan , Nicholas Piggin , Christophe Leroy , Naveen N Rao , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/7] powerpc: properly negate error in syscall_set_return_value() Message-ID: References: <20250113170925.GA392@strace.io> <20250113171054.GA589@strace.io> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250113171054.GA589@strace.io> On Mon, Jan 13, 2025 at 07:10:54PM +0200, Dmitry V. Levin wrote: > Bring syscall_set_return_value() in sync with syscall_get_error(), > and let upcoming ptrace/set_syscall_info selftest pass on powerpc. > > This reverts commit 1b1a3702a65c ("powerpc: Don't negate error in > syscall_set_return_value()"). > > Signed-off-by: Dmitry V. Levin > --- > arch/powerpc/include/asm/syscall.h | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/include/asm/syscall.h b/arch/powerpc/include/asm/syscall.h > index 3dd36c5e334a..422d7735ace6 100644 > --- a/arch/powerpc/include/asm/syscall.h > +++ b/arch/powerpc/include/asm/syscall.h > @@ -82,7 +82,11 @@ static inline void syscall_set_return_value(struct task_struct *task, > */ > if (error) { > regs->ccr |= 0x10000000L; > - regs->gpr[3] = error; > + /* > + * In case of an error regs->gpr[3] contains > + * a positive ERRORCODE. > + */ > + regs->gpr[3] = -error; After this change the syscall_get_error() will return positive value if the system call failed. Since syscall_get_error() still believes regs->gpr[3] is still positive in case !trap_is_scv(). Or am I missing something? It looks like the selftest you mentioned in the commit message doesn't check the !trap_is_scv() branch. > } else { > regs->ccr &= ~0x10000000L; > regs->gpr[3] = val; > -- > ldv -- Rgrds, legion