Hi, The asm-generic/unistd.h file has wrong __NR_userfaultfd syscall number which doesn't even depend on the architecture. This has caused failure of a selftest which was fixed recently [1]. grep -rnIF "#define __NR_userfaultfd" tools/include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282 arch/x86/include/generated/uapi/asm/unistd_32.h:374:#define __NR_userfaultfd 374 arch/x86/include/generated/uapi/asm/unistd_64.h:327:#define __NR_userfaultfd 323 arch/x86/include/generated/uapi/asm/unistd_x32.h:282:#define __NR_userfaultfd (__X32_SYSCALL_BIT + 323) arch/arm/include/generated/uapi/asm/unistd-eabi.h:347:#define __NR_userfaultfd (__NR_SYSCALL_BASE + 388) arch/arm/include/generated/uapi/asm/unistd-oabi.h:359:#define __NR_userfaultfd (__NR_SYSCALL_BASE + 388) include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282 The number is dependent on the architecture. The above data shows that it is different for different arch: x86 374 x86_64 323 ARM 347/358 It seems include/uapi/asm-generic/unistd has wrong 282 value in it. Maybe I'm missing some context.. Please have a look at it. The __NR_userfaultfd was added to include/uapi/asm-generic/unistd.h in 09f7298100ea ("Subject: [PATCH] userfaultfd: register uapi generic syscall (aarch64)"). [1] https://lore.kernel.org/all/20240912103151.1520254-1-usama.anjum@xxxxxxxxxxxxx -- BR, /Muhammad Usama Anjum