| Message ID | b74ac90e869f71a98a04b834c4f3b5ab37bb38ea.1646255044.git.gascoar@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | staging: vc04_services: address W=1 warnings | expand |
On Wed, Mar 02, 2022 at 06:36:38PM -0300, Gaston Gonzalez wrote: > Fix "no previous prototype" W=1 warning by adding the prototype of the > function vchiq_platform_init(). > > Note: vchiq_platform_init() is only called once in vchiq_probe(), so > presumably should be static function. However, making the function > static breaks the build. > That's weird. I don't have an ARM cross compile set up. How does the build break? regards, dan carpenter
On Thu, Mar 03, 2022 at 03:25:47PM +0300, Dan Carpenter wrote: > On Wed, Mar 02, 2022 at 06:36:38PM -0300, Gaston Gonzalez wrote: > > Fix "no previous prototype" W=1 warning by adding the prototype of the > > function vchiq_platform_init(). > > > > Note: vchiq_platform_init() is only called once in vchiq_probe(), so > > presumably should be static function. However, making the function > > static breaks the build. > > > > That's weird. I don't have an ARM cross compile set up. How does the > build break? > > regards, > dan carpenter > Hi Dan, Test building the driver in x86 I get the error pasted below. However, now that you mention it, I made an ARM (64 bit) cross compilation: making the function static builds OK without the warning. I'll to do the same for a 32 bit setup. So I suppose that making the function static is the right approach ? FWIW, branch and cross-compiler: - Remote: https://github.com/raspberrypi/linux.git - Branch: rpi-5.17.y - gcc: aarch64-linux-gnu-gcc (Debian 10.2.1-6) 10.2.1 20210110 -> x86 build error: CC [M] drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.o In function ‘free_pagelist’, inlined from ‘vchiq_complete_bulk’ at drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:650:3: drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:434:4: error: argument 2 null where non-null expected [-Werror=nonnull] 434 | memcpy((char *)kmap(pages[0]) + | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 435 | pagelist->offset, | ~~~~~~~~~~~~~~~~~ 436 | fragments, | ~~~~~~~~~~ 437 | head_bytes); | ~~~~~~~~~~~ In file included from ./arch/x86/include/asm/string.h:5, from ./include/linux/string.h:20, from ./include/linux/bitmap.h:11, from ./include/linux/cpumask.h:12, from ./arch/x86/include/asm/cpumask.h:5, from ./arch/x86/include/asm/msr.h:11, from ./arch/x86/include/asm/processor.h:22, from ./arch/x86/include/asm/timex.h:5, from ./include/linux/timex.h:65, from ./include/linux/time32.h:13, from ./include/linux/time.h:60, from ./include/linux/stat.h:19, from ./include/linux/module.h:13, from drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:8: drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c: In function ‘vchiq_complete_bulk’: ./arch/x86/include/asm/string_64.h:14:14: note: in a call to function ‘memcpy’ declared here 14 | extern void *memcpy(void *to, const void *from, size_t len); | ^~~~~~ cc1: all warnings being treated as errors make[1]: *** [scripts/Makefile.build:288: drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.o] Error 1 make: *** [Makefile:1831: drivers/staging/vc04_services] Error 2 regards, Gaston
On Fri, Mar 04, 2022 at 04:30:15PM -0300, Gaston Gonzalez wrote: > On Thu, Mar 03, 2022 at 03:25:47PM +0300, Dan Carpenter wrote: > > On Wed, Mar 02, 2022 at 06:36:38PM -0300, Gaston Gonzalez wrote: > > > Fix "no previous prototype" W=1 warning by adding the prototype of the > > > function vchiq_platform_init(). > > > > > > Note: vchiq_platform_init() is only called once in vchiq_probe(), so > > > presumably should be static function. However, making the function > > > static breaks the build. > > > > > > > That's weird. I don't have an ARM cross compile set up. How does the > > build break? > > > > regards, > > dan carpenter > > > > Hi Dan, > > Test building the driver in x86 I get the error pasted below. > > However, now that you mention it, I made an ARM (64 bit) cross > compilation: making the function static builds OK without the warning. > I'll to do the same for a 32 bit setup. > > So I suppose that making the function static is the right approach ? > > FWIW, branch and cross-compiler: > > - Remote: https://github.com/raspberrypi/linux.git > - Branch: rpi-5.17.y > - gcc: aarch64-linux-gnu-gcc (Debian 10.2.1-6) 10.2.1 20210110 > > > -> x86 build error: > > CC [M] drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.o > In function ‘free_pagelist’, > inlined from ‘vchiq_complete_bulk’ at drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:650:3: > drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:434:4: error: argument 2 null where non-null expected [-Werror=nonnull] > 434 | memcpy((char *)kmap(pages[0]) + > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 435 | pagelist->offset, > | ~~~~~~~~~~~~~~~~~ > 436 | fragments, > | ~~~~~~~~~~ > 437 | head_bytes); > | ~~~~~~~~~~~ > In file included from ./arch/x86/include/asm/string.h:5, > from ./include/linux/string.h:20, > from ./include/linux/bitmap.h:11, > from ./include/linux/cpumask.h:12, > from ./arch/x86/include/asm/cpumask.h:5, > from ./arch/x86/include/asm/msr.h:11, > from ./arch/x86/include/asm/processor.h:22, > from ./arch/x86/include/asm/timex.h:5, > from ./include/linux/timex.h:65, > from ./include/linux/time32.h:13, > from ./include/linux/time.h:60, > from ./include/linux/stat.h:19, > from ./include/linux/module.h:13, > from drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:8: > drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c: In function ‘vchiq_complete_bulk’: > ./arch/x86/include/asm/string_64.h:14:14: note: in a call to function ‘memcpy’ declared here > 14 | extern void *memcpy(void *to, const void *from, size_t len); > | ^~~~~~ > cc1: all warnings being treated as errors > make[1]: *** [scripts/Makefile.build:288: drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.o] Error 1 > make: *** [Makefile:1831: drivers/staging/vc04_services] Error 2 That's so weird. 1) The GCC warning is a false positive, but -Werror means we have to deal with it. 2) I can't explain the false positive. 3) My guess is that making the function static affects how it is inlined so it gives the compiler more visibility into how free_pagelist()? is called so that's why it gets triggered because of the patch? 4) This is an x86 config and it's an ARM driver, but nothing in the Kconfig file says that vchiq_arm needs ARM or raspberry pi. Should there be? And a COMPILE_TEST option? Anyway, we don't paper over warnings like this so the patch is not the correct thing. Especially we don't paper over it without a giant comment explaining how we filed a bug with GCC or whatever and a link to bugzilla and all that other stuff. regards, dan carpenter
On Wed, Mar 02, 2022 at 06:36:38PM -0300, Gaston Gonzalez wrote: > Fix "no previous prototype" W=1 warning by adding the prototype of the > function vchiq_platform_init(). > > Note: vchiq_platform_init() is only called once in vchiq_probe(), so > presumably should be static function. However, making the function > static breaks the build. > > Signed-off-by: Gaston Gonzalez <gascoar@gmail.com> > --- > drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h > index 2aa46b119a46..d72edaf7e5e9 100644 > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h > @@ -122,6 +122,8 @@ vchiq_instance_get_trace(struct vchiq_instance *instance); > extern void > vchiq_instance_set_trace(struct vchiq_instance *instance, int trace); > > +int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state *state); > + It is a static function, so don't add a prototype here to say it is not :( thanks, greg k-h
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h index 2aa46b119a46..d72edaf7e5e9 100644 --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h @@ -122,6 +122,8 @@ vchiq_instance_get_trace(struct vchiq_instance *instance); extern void vchiq_instance_set_trace(struct vchiq_instance *instance, int trace); +int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state *state); + #if IS_ENABLED(CONFIG_VCHIQ_CDEV) extern void
Fix "no previous prototype" W=1 warning by adding the prototype of the function vchiq_platform_init(). Note: vchiq_platform_init() is only called once in vchiq_probe(), so presumably should be static function. However, making the function static breaks the build. Signed-off-by: Gaston Gonzalez <gascoar@gmail.com> --- drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h | 2 ++ 1 file changed, 2 insertions(+)