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Date:   Fri, 4 Mar 2022 07:34:44 -0800
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Subject: Re: [PATCH] mips: DEC: honor CONFIG_MIPS_FP_SUPPORT=n
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To:     "Maciej W. Rozycki" <macro@orcam.me.uk>
Cc:     linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        kernel test robot <lkp@intel.com>,
        Paul Burton <paulburton@kernel.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-mips@vger.kernel.org
References: <20220304011328.27459-1-rdunlap@infradead.org>
 <alpine.DEB.2.21.2203040857500.47558@angie.orcam.me.uk>
From:   Randy Dunlap <rdunlap@infradead.org>
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On 3/4/22 01:07, Maciej W. Rozycki wrote:
> On Thu, 3 Mar 2022, Randy Dunlap wrote:
> 
>> Include the DECstation interrupt handler in opting out of
>> FPU support.
>>
>> Fixes a linker error:
>>
>> mips-linux-ld: arch/mips/dec/int-handler.o: in function `fpu':
>> (.text+0x148): undefined reference to `handle_fpe_int'
>>
>> Fixes: 183b40f992c8 ("MIPS: Allow FP support to be disabled")
>> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
>> Reported-by: kernel test robot <lkp@intel.com>
>> Cc: Paul Burton <paulburton@kernel.org>
>> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
>> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
>> Cc: linux-mips@vger.kernel.org
>> ---
>> This builds OK. Is it enough for runtime interrupt handling?
> 
>  There's:
> 
> #ifdef CONFIG_32BIT
> 	lw	t2,cpu_fpu_mask
> #endif
> 
> earlier on that needs to go too, and code in arch/mips/dec/setup.c below:
> 
> 	/* Register board interrupts: FPU and cascade. */
> 
> (we don't want an unhandled interrupt unmasked).  Are you happy to do such 
> an update or shall I?
> 
>  I cannot verify that change at run time, because any program that does FP 
> will then crash.  Maybe init(8) and sulogin(8) won't.  I can check that.
> 
>  Thanks for doing this stuff!

I'll update the patch and send v2.

thanks.

-- 
~Randy