drivers/video/fbdev/aty/atyfb_base.c:2327:24: warning: variable 'fb_list' set but not used
From: kernel test robot
Date: Sun Mar 29 2026 - 21:39:30 EST
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 7aaa8047eafd0bd628065b15757d9b48c5f9c07d
commit: a0e2cb6a90634f3dc80f16e882a683ee5761b0b0 um: Add VFIO-based virtual PCI driver
date: 11 months ago
config: um-randconfig-002-20260330 (https://download.01.org/0day-ci/archive/20260330/202603300931.osMYxYZ7-lkp@xxxxxxxxx/config)
compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project 2cd67b8b69f78e3f95918204320c3075a74ba16c)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260330/202603300931.osMYxYZ7-lkp@xxxxxxxxx/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603300931.osMYxYZ7-lkp@xxxxxxxxx/
All warnings (new ones prefixed by >>):
In file included from drivers/video/fbdev/aty/atyfb_base.c:64:
In file included from include/linux/fb.h:5:
In file included from include/uapi/linux/fb.h:6:
In file included from include/linux/i2c.h:19:
In file included from include/linux/regulator/consumer.h:35:
In file included from include/linux/suspend.h:5:
In file included from include/linux/swap.h:9:
In file included from include/linux/memcontrol.h:13:
In file included from include/linux/cgroup.h:26:
In file included from include/linux/kernel_stat.h:8:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/um/include/asm/hardirq.h:5:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:12:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:549:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
549 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:567:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
567 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
| ^
In file included from drivers/video/fbdev/aty/atyfb_base.c:64:
In file included from include/linux/fb.h:5:
In file included from include/uapi/linux/fb.h:6:
In file included from include/linux/i2c.h:19:
In file included from include/linux/regulator/consumer.h:35:
In file included from include/linux/suspend.h:5:
In file included from include/linux/swap.h:9:
In file included from include/linux/memcontrol.h:13:
In file included from include/linux/cgroup.h:26:
In file included from include/linux/kernel_stat.h:8:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/um/include/asm/hardirq.h:5:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:12:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:585:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
585 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
| ^
In file included from drivers/video/fbdev/aty/atyfb_base.c:64:
In file included from include/linux/fb.h:5:
In file included from include/uapi/linux/fb.h:6:
In file included from include/linux/i2c.h:19:
In file included from include/linux/regulator/consumer.h:35:
In file included from include/linux/suspend.h:5:
In file included from include/linux/swap.h:9:
In file included from include/linux/memcontrol.h:13:
In file included from include/linux/cgroup.h:26:
In file included from include/linux/kernel_stat.h:8:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/um/include/asm/hardirq.h:5:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:12:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:601:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
601 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:616:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
616 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:631:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
631 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:724:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
724 | readsb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:737:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
737 | readsw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:750:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
750 | readsl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:764:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
764 | writesb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:778:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
778 | writesw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:792:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
792 | writesl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
>> drivers/video/fbdev/aty/atyfb_base.c:2327:24: warning: variable 'fb_list' set but not used [-Wunused-but-set-global]
2327 | static struct fb_info *fb_list = NULL;
| ^
13 warnings generated.
vim +/fb_list +2327 drivers/video/fbdev/aty/atyfb_base.c
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 2322
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 2323 /*
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 2324 * Initialisation
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 2325 */
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 2326
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 @2327 static struct fb_info *fb_list = NULL;
^1da177e4c3f415 drivers/video/aty/atyfb_base.c Linus Torvalds 2005-04-16 2328
:::::: The code at line 2327 was first introduced by commit
:::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2
:::::: TO: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx>
:::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx>
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