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Date: Mon, 27 Jan 2025 13:20:23 +0200
From: "Dmitry V. Levin" <ldv@strace.io>
To: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Alexey Gladkov <legion@kernel.org>, Oleg Nesterov <oleg@redhat.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
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	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/7] powerpc: properly negate error in
 syscall_set_return_value()
Message-ID: <20250127112023.GB29522@strace.io>
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In-Reply-To: <86079b5c-e124-489b-8136-05ae5700cb61@csgroup.eu>

On Thu, Jan 23, 2025 at 11:07:21PM +0100, Christophe Leroy wrote:
[...]
> To add a bit more to the confusion,

Looks like there is no end to it:

static inline long regs_return_value(struct pt_regs *regs)
{
        if (trap_is_scv(regs))
                return regs->gpr[3];

        if (is_syscall_success(regs))
                return regs->gpr[3];
        else
                return -regs->gpr[3];
}

static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
{
        regs->gpr[3] = rc;
}

This doesn't look consistent, does it?


-- 
ldv