From: Kees Cook <keescook@xxxxxxxxxxxx> [ Upstream commit 0dedcf6e3301836eb70cfa649052e7ce4fcd13ba ] Clang is especially sensitive about argument type matching when using __overloaded functions (like memcmp(), etc). Help it see that function pointers are just "void *". Avoids this error: arch/mips/bcm47xx/prom.c:89:8: error: no matching function for call to 'memcmp' if (!memcmp(prom_init, prom_init + mem, 32)) ^~~~~~ include/linux/string.h:156:12: note: candidate function not viable: no known conversion from 'void (void)' to 'const void *' for 1st argument extern int memcmp(const void *,const void *,__kernel_size_t); Cc: Hauke Mehrtens <hauke@xxxxxxxxxx> Cc: "Rafał Miłecki" <zajec5@xxxxxxxxx> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxxx Cc: Nathan Chancellor <nathan@xxxxxxxxxx> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Cc: llvm@xxxxxxxxxxxxxxx Reported-by: kernel test robot <lkp@xxxxxxxxx> Link: https://lore.kernel.org/lkml/202209080652.sz2d68e5-lkp@xxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/mips/bcm47xx/prom.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/mips/bcm47xx/prom.c b/arch/mips/bcm47xx/prom.c index 135a5407f015..d26d9a6f6ee7 100644 --- a/arch/mips/bcm47xx/prom.c +++ b/arch/mips/bcm47xx/prom.c @@ -85,7 +85,7 @@ static __init void prom_init_mem(void) pr_debug("Assume 128MB RAM\n"); break; } - if (!memcmp(prom_init, prom_init + mem, 32)) + if (!memcmp((void *)prom_init, (void *)prom_init + mem, 32)) break; } lowmem = mem; @@ -162,7 +162,7 @@ void __init bcm47xx_prom_highmem_init(void) off = EXTVBASE + __pa(off); for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) { - if (!memcmp(prom_init, (void *)(off + extmem), 16)) + if (!memcmp((void *)prom_init, (void *)(off + extmem), 16)) break; } extmem -= lowmem; -- 2.35.1