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Subject: Re: [Qemu-devel] Fwd: [PATCH v2.5] fixup! linux-user/sh4: Notice
 gUSA regions during signal delivery
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To: qemu-devel <qemu-devel@nongnu.org>

On 07/07/2017 07:57 AM, Richard Henderson wrote:
> +    /* ??? The SH4 kernel checks for and address above 0xC0000000.
> +       However, the page mappings in qemu linux-user aren't as restricted
> +       and we wind up with the normal stack mapped above 0xF0000000.
> +       That said, there is no reason why the kernel should be allowing
> +       a gUSA region that spans 1GB.  Use a tighter check here, for what
> +       can actually be enabled by the immediate move.  */

Additionally, I can (and should) fix the address space problem for SH4 in 
linux-user/main.c, where we have already done so for MIPS and Nios2.

See the initialization of reserved_va.


r~