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References: <20170921110625.9500-1-alex.bennee@linaro.org>
From: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <824254ac-23a1-30d5-e64e-e4e3147db6c4@linaro.org>
Date: Mon, 25 Sep 2017 11:22:09 -0700
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Subject: Re: [Qemu-devel] [PATCH] accel/tcg/cputlb: avoid recursive BQL
 (fixes #1706296)
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To: =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>, qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, Paolo Bonzini <bonzini@gnu.org>, Peter Crosthwaite <crosthwaite.peter@gmail.com>, Richard Jones <rjones@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <rth@twiddle.net>

On 09/21/2017 04:06 AM, Alex Bennée wrote:
> The mmio path (see exec.c:prepare_mmio_access) already protects itself
> against recursive locking and it makes sense to do the same for
> io_readx/writex. Otherwise any helper running in the BQL context will
> assert when it attempts to write to device memory as in the case of
> the bug report.
> 
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> CC: Richard Jones <rjones@redhat.com>
> CC: Paolo Bonzini <bonzini@gnu.org>
> ---
>  accel/tcg/cputlb.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

I guess I'll queue this through tcg-next?


r~