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Date: Thu, 30 May 2024 17:18:43 +0200
From: Andrea Parri <parri.andrea@gmail.com>
To: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Leonardo Bras <leobras@redhat.com>, linux-riscv@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH -fixes v2] riscv: Fix fully ordered LR/SC xchg[8|16]()
 implementations
Message-ID: <ZliY0ytpksarswi6@andrea>
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On Thu, May 30, 2024 at 04:55:46PM +0200, Alexandre Ghiti wrote:
> The fully ordered versions of xchg[8|16]() using LR/SC lack the
> necessary memory barriers to guarantee the order.
> 
> Fix this by matching what is already implemented in the fully ordered
> versions of cmpxchg() using LR/SC.
> 
> Suggested-by: Andrea Parri <parri.andrea@gmail.com>
> Reported-by: Andrea Parri <parri.andrea@gmail.com>
> Closes: https://lore.kernel.org/linux-riscv/ZlYbupL5XgzgA0MX@andrea/T/#u
> Fixes: a8ed2b7a2c13 ("riscv/cmpxchg: Implement xchg for variables of size 1 and 2")
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>

Reviewed-by: Andrea Parri <parri.andrea@gmail.com>

Thanks!

  Andrea