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From: Richard Henderson <richard.henderson@linaro.org>
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Date: Wed, 15 Nov 2017 10:39:32 +0100
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Subject: Re: [Qemu-devel] [PATCH] tcg: Record code_gen_buffer address for
 user-only memory helpers
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To: =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>
Cc: qemu-devel@nongnu.org, peter.maydell@linaro.org

On 11/14/2017 05:09 PM, Alex Bennée wrote:
>> -    /* Now we have a real cpu fault.  Since this is the exact location of
>> -     * the exception, we must undo the adjustment done by cpu_restore_state
>> -     * for handling call return addresses.  */
>> -    cpu_restore_state(cpu, pc + GETPC_ADJ);
>> +    /* Now we have a real cpu fault.  */
>> +    cpu_restore_state(cpu, pc);
> 
> I can't help thinking when we get it wrong we should be doing something
> here, maybe a LOG_UNIMP? Otherwise we silently fail or at least the
> user-space falls off a cliff later.

Oh we silently get it wrong in so many ways.  E.g. zero callers of
cpu_restore_state_from_tb check its return status.  Anyway, I think this sort
of cleanup has to wait til next cycle.


r~