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References: <1529944302-14186-1-git-send-email-cota@braap.org>
From: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <168807dc-6c5b-fc1f-6a70-72e0a518b178@linaro.org>
Date: Tue, 26 Jun 2018 19:28:19 -0700
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Subject: Re: [Qemu-devel] [PATCH] translate-all: fix locking of TBs whose
 two pages share the same physical page
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To: "Emilio G. Cota" <cota@braap.org>, qemu-devel@nongnu.org
Cc: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= <f4bug@amsat.org>, =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>, Fam Zheng <famz@redhat.com>, Max Filippov <jcmvbkbc@gmail.com>

On 06/25/2018 09:31 AM, Emilio G. Cota wrote:
> +    } else if (page1 == page2) {
> +        page_lock(p1);
> +        if (ret_p2) {
> +            *ret_p2 = p1;

I think you should set NULL here...

> @@ -1623,7 +1641,7 @@ tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc,
>          tb = existing_tb;
>      }
>  
> -    if (p2) {
> +    if (p2 && p2 != p) {
>          page_unlock(p2);

... so that you need no change here.
Otherwise it looks good.


r~