On Thu, 21 Aug 2025 at 16:26, Naresh Kamboju naresh.kamboju@linaro.org wrote:

The following build warnings / errors noticed with mips defconfig with clang-20 and gcc-12 toolchains.

Regression Analysis:

• New regression? yes
• Reproducibility? yes

Build regression: next-20250821 cacheflush.h:61:3: error: incompatible pointer types passing 'memdesc_flags_t *' to parameter of type 'volatile unsigned long *' [-Werror,-Wincompatible-pointer-types]

Anders bisected and found this,

# first bad commit: [30f45bf18d55a411f576afe48d50e78a2eef7e23] mm: introduce memdesc_flags_t

Reported-by: Linux Kernel Functional Testing lkft@linaro.org

• mips, build
  • clang-nightly-allnoconfig
  • clang-nightly-defconfig
  • clang-nightly-lkftconfig-hardening
  • clang-nightly-lkftconfig-lto-full
  • clang-nightly-lkftconfig-lto-thing
  • clang-nightly-tinyconfig
  • gcc-12-allnoconfig
  • gcc-12-ath79_defconfig
  • gcc-12-bcm47xx_defconfig
  • gcc-12-bcm63xx_defconfig
  • gcc-12-cavium_octeon_defconfig
  • gcc-12-defconfig
  • gcc-12-malta_defconfig
  • gcc-12-rt305x_defconfig
  • gcc-12-tinyconfig
  • gcc-13-lkftconfig-hardening
  • gcc-8-allnoconfig
  • gcc-8-ath79_defconfig
  • gcc-8-bcm47xx_defconfig
  • gcc-8-bcm63xx_defconfig
  • gcc-8-cavium_octeon_defconfig
  • gcc-8-defconfig
  • gcc-8-lkftconfig-hardening
  • gcc-8-malta_defconfig
  • gcc-8-rt305x_defconfig
  • gcc-8-tinyconfig

## Build error mips In file included from include/linux/cacheflush.h:5: arch/mips/include/asm/cacheflush.h:61:3: error: incompatible pointer types passing 'memdesc_flags_t *' to parameter of type 'volatile unsigned long *' [-Werror,-Wincompatible-pointer-types] 61 | folio_set_dcache_dirty(folio); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/mips/include/asm/cacheflush.h:42:27: note: expanded from macro 'folio_set_dcache_dirty' 42 | set_bit(PG_dcache_dirty, &(folio)->flags) | ^~~~~~~~~~~~~~~ arch/mips/include/asm/bitops.h:89:70: note: passing argument to parameter 'addr' here 89 | static inline void set_bit(unsigned long nr, volatile unsigned long *addr) | ^

In file included from include/linux/cacheflush.h:5: arch/mips/include/asm/cacheflush.h:70:3: error: incompatible pointer types passing 'memdesc_flags_t *' to parameter of type 'volatile unsigned long *' [-Werror,-Wincompatible-pointer-types] 70 | folio_set_dcache_dirty(page_folio(page)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/mips/include/asm/cacheflush.h:42:27: note: expanded from macro 'folio_set_dcache_dirty' 42 | set_bit(PG_dcache_dirty, &(folio)->flags) | ^~~~~~~~~~~~~~~ arch/mips/include/asm/bitops.h:89:70: note: passing argument to parameter 'addr' here 89 | static inline void set_bit(unsigned long nr, volatile unsigned long *addr) | ^ 2 errors generated.

## Source

• Kernel version: 6.17.0-rc2
• Git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git
• Git describe: next-20250821
• Git commit: 7fa4d8dc380fbd81a9d702a855c50690c9c6442c
• Architectures: mips
• Toolchains: clang-20 gcc-12
• Kconfigs: defconfig

## Build

• Build log: https://qa-reports.linaro.org/api/testruns/29616797/log_file/
• Build details mips:

https://regressions.linaro.org/lkft/linux-next-master/next-20250821/build/cl...

• Build plan: https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/builds/31aRYnoYJb...
• Build link: https://storage.tuxsuite.com/public/linaro/lkft/builds/31aRYnoYJbpEW0zZyTGvO...
• Kernel config:

https://storage.tuxsuite.com/public/linaro/lkft/builds/31aRYnoYJbpEW0zZyTGvO...

-- Linaro LKFT https://lkft.linaro.org

- Naresh