Re: [PATCH v3] powerpc/fsl-85xx: fix compile error

Re: [PATCH v3] powerpc/fsl-85xx: fix compile error

[Christophe Leroy]

Le 14/03/2020 à 06:10, WANG Wenhu a écrit :
> Include "linux/of_address.h" to fix the compile error for
> mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.
> 
>    CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
>    l2ctlr = of_iomap(dev->dev.of_node, 0);
>             ^~~~~~~~
>             pci_iomap
> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
>    l2ctlr = of_iomap(dev->dev.of_node, 0);
>           ^
> cc1: all warnings being treated as errors
> scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
> make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1
> 
> Fixes: commit 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
> Cc: stable <stable@vger.kernel.org>
> Signed-off-by: WANG Wenhu <wenhu.wang@vivo.com>

Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>

Re: [PATCH v3] powerpc/fsl-85xx: fix compile error

[Michael Ellerman]

WANG Wenhu <wenhu.wang@vivo.com> writes:
> Include "linux/of_address.h" to fix the compile error for
> mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.
>
>   CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>            ^~~~~~~~
>            pci_iomap
> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>          ^
> cc1: all warnings being treated as errors
> scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
> make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1
>
> Fixes: commit 6db92cc9d07d ("powerpc/85xx: add cache-sram support")

The syntax is:

Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")

> Cc: stable <stable@vger.kernel.org>

The commit above went into v2.6.37.

So no one has noticed this bug since then, how? Or did something else
change to expose the problem?

cheers

Re: [PATCH v3] powerpc/fsl-85xx: fix compile error

[王文虎]

From: Michael Ellerman <mpe@ellerman.id.au>
 Date: 2020-03-16 17:41:12
To:WANG Wenhu <wenhu.wang@vivo.com>,Benjamin Herrenschmidt <benh@kernel.crashing.org>,Paul Mackerras <paulus@samba.org>,WANG Wenhu <wenhu.wang@vivo.com>,Allison Randal <allison@lohutok.net>,Richard Fontana <rfontana@redhat.com>,Greg Kroah-Hartman <gregkh@linuxfoundation.org>,Thomas Gleixner <tglx@linutronix.de>,linuxppc-dev@lists.ozlabs.org,linux-kernel@vger.kernel.org
 cc: trivial@kernel.org,kernel@vivo.com,stable <stable@vger.kernel.org>
Subject: Re: [PATCH v3] powerpc/fsl-85xx: fix compile error>WANG Wenhu <wenhu.wang@vivo.com> writes:
>> Include "linux/of_address.h" to fix the compile error for
>> mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.
>>
>>   CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
>>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>>            ^~~~~~~~
>>            pci_iomap
>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
>>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>>          ^
>> cc1: all warnings being treated as errors
>> scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
>> make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1
>>
>> Fixes: commit 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
>
>The syntax is:
>
>Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
>
>> Cc: stable <stable@vger.kernel.org>
>
>The commit above went into v2.6.37.
>
>So no one has noticed this bug since then, how? Or did something else
>change to expose the problem?

Actually a hard question to answer cause it also left me scratching for long.
However, I can not find right or definite answer.

A convincing explanation is the driver has not been in use since v2.6.37,
but somehow, we are to use it recently.
Anyway, it's better for me as well as no harm to anyone to fix it even though.

Thanks, Wenhu
>
>cheers

Re: [PATCH v3] powerpc/fsl-85xx: fix compile error

[Michael Ellerman]

王文虎 <wenhu.wang@vivo.com> writes:
> From: Michael Ellerman <mpe@ellerman.id.au>
>  Date: 2020-03-16 17:41:12
> To:WANG Wenhu <wenhu.wang@vivo.com>,Benjamin Herrenschmidt <benh@kernel.crashing.org>,Paul Mackerras <paulus@samba.org>,WANG Wenhu <wenhu.wang@vivo.com>,Allison Randal <allison@lohutok.net>,Richard Fontana <rfontana@redhat.com>,Greg Kroah-Hartman <gregkh@linuxfoundation.org>,Thomas Gleixner <tglx@linutronix.de>,linuxppc-dev@lists.ozlabs.org,linux-kernel@vger.kernel.org
>  cc: trivial@kernel.org,kernel@vivo.com,stable <stable@vger.kernel.org>
> Subject: Re: [PATCH v3] powerpc/fsl-85xx: fix compile error>WANG Wenhu <wenhu.wang@vivo.com> writes:
>>> Include "linux/of_address.h" to fix the compile error for
>>> mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.
>>>
>>>   CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
>>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
>>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
>>>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>>>            ^~~~~~~~
>>>            pci_iomap
>>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
>>>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>>>          ^
>>> cc1: all warnings being treated as errors
>>> scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
>>> make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1
>>>
>>> Fixes: commit 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
>>
>>The syntax is:
>>
>>Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
>>
>>> Cc: stable <stable@vger.kernel.org>
>>
>>The commit above went into v2.6.37.
>>
>>So no one has noticed this bug since then, how? Or did something else
>>change to expose the problem?
>
> Actually a hard question to answer cause it also left me scratching for long.
> However, I can not find right or definite answer.

Oh, actually it's fairly straight forward, the code can't be built at
all in upstream because CONFIG_FSL_85XX_CACHE_SRAM is not selectable or
selected by anything.

You sent a patch previously to make it selectable, which Scott thought
was a bad idea.

So this whole file is dead code as far as I'm concerned, so patches for
it definitely do not need to go to stable.

If you want to add a user for it then please send a series doing that,
and this commit can be the first.

cheers

Re:Re: [PATCH v3] powerpc/fsl-85xx: fix compile error

[王文虎]

From: Michael Ellerman <mpe@ellerman.id.au>
 Date: 2020-03-17 19:22:13
To:"王文虎" <wenhu.wang@vivo.com>
 cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,Paul Mackerras <paulus@samba.org>,Allison Randal <allison@lohutok.net>,Richard Fontana <rfontana@redhat.com>,Greg Kroah-Hartman <gregkh@linuxfoundation.org>,Thomas Gleixner <tglx@linutronix.de>,linuxppc-dev@lists.ozlabs.org,linux-kernel@vger.kernel.org,trivial@kernel.org,kernel@vivo.com,stable <stable@vger.kernel.org>
Subject: Re: [PATCH v3] powerpc/fsl-85xx: fix compile error>王文虎 <wenhu.wang@vivo.com> writes:
>> From: Michael Ellerman <mpe@ellerman.id.au>
>>  Date: 2020-03-16 17:41:12
>> To:WANG Wenhu <wenhu.wang@vivo.com>,Benjamin Herrenschmidt <benh@kernel.crashing.org>,Paul Mackerras <paulus@samba.org>,WANG Wenhu <wenhu.wang@vivo.com>,Allison Randal <allison@lohutok.net>,Richard Fontana <rfontana@redhat.com>,Greg Kroah-Hartman <gregkh@linuxfoundation.org>,Thomas Gleixner <tglx@linutronix.de>,linuxppc-dev@lists.ozlabs.org,linux-kernel@vger.kernel.org
>>  cc: trivial@kernel.org,kernel@vivo.com,stable <stable@vger.kernel.org>
>> Subject: Re: [PATCH v3] powerpc/fsl-85xx: fix compile error>WANG Wenhu <wenhu.wang@vivo.com> writes:
>>>> Include "linux/of_address.h" to fix the compile error for
>>>> mpc85xx_l2ctlr_of_probe() when compiling fsl_85xx_cache_sram.c.
>>>>
>>>>   CC      arch/powerpc/sysdev/fsl_85xx_l2ctlr.o
>>>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c: In function ‘mpc85xx_l2ctlr_of_probe’:
>>>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:11: error: implicit declaration of function ‘of_iomap’; did you mean ‘pci_iomap’? [-Werror=implicit-function-declaration]
>>>>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>>>>            ^~~~~~~~
>>>>            pci_iomap
>>>> arch/powerpc/sysdev/fsl_85xx_l2ctlr.c:90:9: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
>>>>   l2ctlr = of_iomap(dev->dev.of_node, 0);
>>>>          ^
>>>> cc1: all warnings being treated as errors
>>>> scripts/Makefile.build:267: recipe for target 'arch/powerpc/sysdev/fsl_85xx_l2ctlr.o' failed
>>>> make[2]: *** [arch/powerpc/sysdev/fsl_85xx_l2ctlr.o] Error 1
>>>>
>>>> Fixes: commit 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
>>>
>>>The syntax is:
>>>
>>>Fixes: 6db92cc9d07d ("powerpc/85xx: add cache-sram support")
>>>
>>>> Cc: stable <stable@vger.kernel.org>
>>>
>>>The commit above went into v2.6.37.
>>>
>>>So no one has noticed this bug since then, how? Or did something else
>>>change to expose the problem?
>>
>> Actually a hard question to answer cause it also left me scratching for long.
>> However, I can not find right or definite answer.
>
>Oh, actually it's fairly straight forward, the code can't be built at
>all in upstream because CONFIG_FSL_85XX_CACHE_SRAM is not selectable or
>selected by anything.

Yeah, sure that is the reason, and I meant it was hard to figure out why
nobody had ever compiled the driver with FSL_85XX_CACHE_SRAM enabled
until me.
>
>You sent a patch previously to make it selectable, which Scott thought
>was a bad idea.
>
>So this whole file is dead code as far as I'm concerned, so patches for
>it definitely do not need to go to stable.
>
>If you want to add a user for it then please send a series doing that,
>and this commit can be the first.

For this, as you mentioned, it is dead and do not need to be applied to any stable.
And I recommand the patch as a unit itself cause our module which uses
it is still under developing, and the module itself would be taken as a
complete logical block. Also it would take some time.

Thanks, Wenhu
>
>cheers