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From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To: Alexandre Ghiti <alexghiti@rivosinc.com>, Paul Walmsley
 <paul.walmsley@sifive.com>, Palmer Dabbelt <palmer@dabbelt.com>, Albert Ou
 <aou@eecs.berkeley.edu>, Anup Patel <anup@brainfault.org>, Steven Rostedt
 <rostedt@goodmis.org>, Masami Hiramatsu <mhiramat@kernel.org>, Mark
 Rutland <mark.rutland@arm.com>, linux-riscv@lists.infradead.org,
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Cc: Alexandre Ghiti <alexghiti@rivosinc.com>, =?utf-8?B?QmrDtnJuIFTDtnBl?=
 =?utf-8?B?bA==?= <bjorn@rivosinc.com>
Subject: Re: [PATCH] riscv: Fix text patching when icache flushes use IPIs
In-Reply-To: <20240206204607.527195-1-alexghiti@rivosinc.com>
References: <20240206204607.527195-1-alexghiti@rivosinc.com>
Date: Wed, 07 Feb 2024 08:30:58 +0100
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Alexandre Ghiti <alexghiti@rivosinc.com> writes:

> For now, we use stop_machine() to patch the text and when we use IPIs for
> remote icache flushes, the system hangs since the irqs are disabled on all
> cpus.
>
> So instead, make sure every cpu executes the stop_machine() patching
> function which emits a local icache flush and then avoids the use of
> IPIs.
>
> Co-developed-by: Bj=C3=B6rn T=C3=B6pel <bjorn@rivosinc.com>
> Signed-off-by: Bj=C3=B6rn T=C3=B6pel <bjorn@rivosinc.com>
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>

FWIW, the BPF selftests pass nicely with this (especially the
fentry/fexit tests ;-)). I don't know if it's worth much saying that
your own stuff was tested, but here goes:

Tested-by: Bj=C3=B6rn T=C3=B6pel <bjorn@rivosinc.com>