Re: [kbuild-all] Re: drivers/video/fbdev/pxafb.c:916:24: sparse: sparse: incorrect type in assignment (different address spaces)

From: Rong Chen
Date: Sun Aug 09 2020 - 22:51:03 EST

On 8/7/20 7:53 PM, Luc Van Oostenryck wrote:
On Fri, Aug 07, 2020 at 06:37:36PM +0800, kernel test robot wrote:
tree: master
head: 86cfccb66937dd6cbf26ed619958b9e587e6a115
commit: 670d0a4b10704667765f7d18f7592993d02783aa sparse: use identifiers to define address spaces
date: 7 weeks ago
config: arm-randconfig-s031-20200807 (attached as .config)
compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0
wget -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.2-118-ge1578773-dirty
git checkout 670d0a4b10704667765f7d18f7592993d02783aa
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

sparse warnings: (new ones prefixed by >>)

drivers/video/fbdev/pxafb.c:916:24: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected void [noderef] __iomem *video_mem @@ got void * @@
drivers/video/fbdev/pxafb.c:916:24: sparse: expected void [noderef] __iomem *video_mem

since late June I receive several mails per day about this commit but
they are all false-positive.
Commit 670d0a4b10704667765f7d18f7592993d02783aa can't introduce *new*
warnings, it only change how address-spaces are displayed in sparse's
warnings (for example, the address space for __user pointers were
displayd as '<asn:1>', now it's nicely displayed as '__user', same
for '__iomem', '__percpu' and '__rcu').

Isn't it possible to ignore some commits like this one?

Hi Luc,

Sorry for the inconvenience, we'll ignore this commit firstly.

Or, even better, should it be possible to only report when a new
warning is effectively added, not when its content is simply modified?
If not it would be nice to be able to see the difference in a diff-like
Thanks for your advice, we'll seriously consider it.

Best Regards,
Rong Chen