Re: [PATCH] linux-user/sh4: allow full 32-bit address space

On 7/27/26 14:48, Laurent Vivier wrote:
> On real SH4 hardware, the address space is split between user mode
> (U0, 0x00000000-0x7fffffff) and kernel mode (P1-P4, 0x80000000-0xffffffff),
> so TARGET_VIRT_ADDR_SPACE_BITS was set to 31 for CONFIG_USER_ONLY.
> 
> However, qemu-user does not emulate the MMU, so this limit is not needed.
> The only effect is to restrict reserved_va to 2 GB, causing OOM failures
> for memory-intensive builds (e.g. webkit2gtk on Debian sh4 buildds).
> 
> Set TARGET_VIRT_ADDR_SPACE_BITS to 32 unconditionally, like most other
> 32-bit targets. Also fix the TASK_UNMAPPED_BASE macro to use 1ull instead
> of 1u to avoid undefined behavior when shifting by 32.

Should I pick this one for the stable series too?  So it will find its
way to debian too, for example, so sh4 buildd(s) will feel a bit better? :)

Thanks,

/mjt